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The International Journal of Oral & Maxillofacial Implants 1359
The global shift in the dental field toward mini-mally invasive approaches has enabled enhanced
patient care with decreased postoperative pain and healing duration. The current widespread use of short implants stems from this phenomenon. The definition of short implants has been variable throughout the
last decade, gradually evolving to decreased lengths. In 2013, Monje and coworkers defined a short implant as being ≤ 10 mm in length.1 Today, ≤ 6 mm is classi-fied as either a short2 or extra-short3,4 implant. When applied in cases of atrophic arches, complexities as-sociated with more invasive surgical procedures, such as maxillary sinus floor elevation (SFE), guided bone regeneration, onlay bone grafts, distraction osteogen-esis, and inferior alveolar nerve transpositioning are avoided.5 Consequently, the use of short implants has been positively correlated with a reduction in biologic complications, overall chair time, total cost,6 and posi-tive patient-reported outcomes.7
The clinical performance of short implants com-pared with bone augmentation and long implants in atrophic sites has been assessed through several ran-domized clinical trials. In the maxilla, Pohl and cowork-ers compared 6-mm implants vs long dental implants (11 to 15 mm) in combination with SFE in 101 patients. Following a 3-year observational period, the survival rate was 100% in both groups.8 In the mandible, Es-posito and coworkers evaluated whether or not 5-mm implants are a viable alternative to 10-mm implants
1Graduate Student, Graduate Periodontics, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, Michigan, USA.
2Graduate Student, Graduate Periodontics, School of Dentistry, University of Louisville, Louisville, Kentucky, USA.
3Professor and Director of Graduate Periodontics, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, Michigan, USA.
Correspondence to: Dr Hom-Lay Wang, Department of Periodontics and Oral Medicine, University of Michigan, School of Dentistry, 1011 North University Avenue, Ann Arbor, MI 48109-1078, USA. Fax: +734-936-0374. Email: [email protected]
Submitted November 25, 2018; accepted July 15, 2019.
Impact of Implant Length on Survival of Rough-Surface Implants in Nonaugmented Posterior Areas:
A Systematic Review and Meta-Regression AnalysisAndrea Ravidà, DDS, MS1/Jad Majzoub, BDS1/Madi Alassadi, BDS1/
Muhammad H. A. Saleh, BDS, MS2/Houssam Askar, BDS1/Hom-Lay Wang, DDS, MS, PhD3
Purpose: Short implants have been considered as an alternative to regular implants even where native
bone is potentially adequate. Hence, the aim of this study was to evaluate the impact of implant length on
its survival. Materials and Methods: A systematic literature search of randomized controlled trials and
prospective studies was performed using the PubMed (MEDLINE), EMBASE, and Cochrane databases. Meta-
regression analysis determined the effect of the length on the implant survival rate. Results: Sixty-six studies
comprising 4,525 implants were included in the meta-regression analysis. Overall, for each additional 1 mm
of length, the survival rate was increased by 0.42 percentage points (P = .056). In the maxilla, an additional
1 mm in length implied 0.68 percentage points more in the rate (P < .001), while in the mandible, statistical
significance was not reached. Eventually, the implant survival rate in the 3- to 5-year period was strongly
affected by the length of the implants in the maxilla, since it increased by 2% for each additional 1 mm of
length. Conclusion: In the presence of adequate native bone, placement of longer/regular-sized implants
should be chosen over placement of short implants in the maxilla. However, in a posterior mandible, short
implants offer a judicious alternative. Int J Oral MaxIllOfac IMplants 2019;34:1359–1369. doi: 10.11607/jomi.7509
Keywords: dental implants, implant survival, review, short implants, systematic
placed after bone augmentation with bovine bone, reporting comparable survival rates between test and control groups after 3 years.9 These promising results are currently leading clinicians toward placing shorter implants, even where native bone is a potentially ad-equate recipient of longer counterparts.10,11 The ra-tionale behind this is supported by two fundamental pillars. First, resorting to shorter implants is typically the more conservative and, in turn, safer option. Sec-ondly, in case peri-implant bone loss ensues beyond corrective treatment, a less complicated implant re-moval procedure is confronted when short implants are used.12 In such a manner, complexities of augmen-tation procedures will be avoided once again. Thus, the aim of this study was to investigate the impact of implant length on the survival rate of rough-surface implants placed in nonaugmented posterior areas of partially edentulous patients.
MATERIALS AND METHODS
Study RegistrationThe protocol of the present study was registered in PROSPERO under the identification number CRD42018104130.
Reporting FormatThe 27-item Systematic Reviews and Meta-Analyses (PRISMA) statement13 was employed in explanation of the search process results. The Assessment of Multiple Systematic Reviews guidelines (AMSTAR)14 was utilized to reach the predetermined standards of systematic reviews.
Patient, Intervention, Comparison, Outcome (PICO) QuestionThe PICO format introduced by Stone in 200215 was used to elaborate the focused research question as follows:
• Patients (P): Patients receiving one or more implants in the posterior area without a bone augmentation procedure
• Intervention (I): Placement of short dental implants in the posterior mandible and/or maxilla
• Comparison (C): Placement of long dental implants in the posterior mandible and/or maxilla
• Outcome (O): Relationship between implant length and survival rate
Focused QuestionDoes implant length, in systemically healthy, partially edentulous patients with a dental implant placed in
the posterior area without a bone augmentation pro-cedure impact short- and long-term survival rates?
Eligibility CriteriaArticles were included in the analysis if they met the following inclusion criteria: (1) controlled prospective cohort studies and randomized controlled trials (RCTs) of ≥ 10 human subjects receiving one or more im-plants; (2) studies specifying implant length; (3) studies that report failed implant information; (4) studies with implants placed in the posterior maxilla/mandible of partially edentulous patients; and (5) studies with im-plants placed in native bone (no bone augmentation prior to implant placement).
The exclusion criteria were: (1) preclinical animal studies, case series, case reports, retrospective cohort studies, systematic reviews; (2) articles not report-ing implant length and/or survival rate; (3) studies with implants placed in augmented bone; (4) studies with edentulous patients rehabilitated with implant-supported full-arch prostheses; (5) studies with ma-chined implants; and (6) studies with implants placed in the anterior maxilla/mandible.
Information Sources and Search StrategyTwo reviewers (H.A., A.R.) conducted electronic litera-ture searches using three databases: (1) MEDLINE (until September 2018), (2) EMBASE (until September 2018), and (3) Cochrane with the following search terms:
• MEDLINE: (((“dental implants”[MeSH Terms] OR (“dental”[All Fields] AND “implants”[All Fields]) OR “dental implants”[All Fields] OR (“dental”[All Fields] AND “implant”[All Fields]) OR “dental implant”[All Fields]) AND (“clinical trial”[Publication Type] OR “clinical trials as topic”[MeSH Terms] OR “clinical trial”[All Fields])) NOT Overdenture[Title/Abstract]) NOT (Full[All Fields] AND (“Arch Otolaryngol”[Journal] OR “arch”[All Fields]))
• EMBASE: (‘dental implants’/exp OR ‘dental implants’ OR ((‘dental’/exp OR dental) AND (‘implants’/exp OR implants))) AND survival
• COCHRANE: “dental implant” in Trials
In addition, a manual search in dental implant–related journals was conducted to ensure a compre-hensive screening process. The article bibliographies of all full-text reviewed papers were also screened to check for further studies. All disagreements were resolved through discussion with a third reviewer (H.L.W.). Kappa value was used to calculate the agree-ment level between reviewers. Furthermore, previous systematic reviews evaluating short implants were also scanned for article identification.16–32
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Data Extraction and AnalysesDuring the first step, articles were excluded when their titles and abstracts failed to meet the eligibility criteria elaborated above. During the second step, two cali-brated reviewers (H.A., J.M.) screened the remaining articles by reading the full text using a predetermined data extraction form to evaluate the eligibility of the se-lected studies based on the aforementioned inclusion and exclusion criteria. During the process, all disagree-ments were discussed with a third reviewer (H.L.W.). Thereafter, patient characteristics and clinical out-comes were independently extracted by three review-ers and systematically recorded. When a study article presented a lack of necessary clinical data, the respec-tive authors were electronically contacted. All statisti-cal analyses were performed using the software R 3.0.2 (R Core Team [2018]. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.). To assess the influence of implant length on survival, a meta-regression with the length as the moderating variable was estimated under the random-effects approach (mixed effects). A series of meta-regressions were performed to evaluate the effects of other variables, including level of implant placement relative to peri-implant bone and time of loading, on the survival rate. The same type of analysis was replicated for the survival rate up to more defined time points (for example, a subanalysis for early fail-ures before loading). The level of significance used in the analyses was set up as 5% (α = .05).
Outcomes and VariablesIn each included study, clinical parameters such as (1) implant characteristics (length, diameter, internal/external connection, bone/soft tissue–level implants), (2) prosthetic parameters (immediate/early/delayed loading, cement/screw-retained prosthesis, splinted/nonsplinted restoration), and (3) surgical parameters (one- or two-stage implant placement) were obtained from the selected articles and analyzed. Survival rate was recorded during each follow-up interval (annual) and defined as the presence of the implant in the mouth with or without complications within the ob-servational period. On the other hand, failure was con-sidered as implant removal independent of the cause. Finally, early failure was defined as implant removal prior to loading.
Risk of Bias and Qualitative AssessmentThe quality assessment of the included articles was performed by two independent reviewers (A.R. and H.A.). To record the bias of all the nonrandomized clinical trials, the indications of the Newcastle-Ottawa Scale were followed.33 Furthermore, the Cochrane Risk of Bias Tool for RCTs was used to assess the bias of all
RCTs, categorizing them as low, moderate, or high risk of bias.34
RESULTS
Study SelectionAfter the initial selection, a total of 8,591 articles (2,795 PubMed [Medline]; 3,529 EMBASE; 1,927 Cochrane) were included in the search. Additionally, 340 addition-al articles were selected through other sources. Overall, 375 were included after title and abstract assessment. A total of 309 articles were excluded after full-text read-ing (Appendix Table 1; see online version of this article at quintpub.com), leaving 66 studies6,8,9,11,35–97 includ-ed in the analysis (Fig 1). The k value for interreviewer agreement for potentially relevant articles was 0.87 (titles and abstracts) and 0.95 (full-text articles).
Risk of BiasFor the 39 included RCTs, the results of the risk of bias assessment according to the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions98 are showed in Appendix Table 2. Overall, 7 studies displayed low risk of bias,52,53,62,70,
71,74,78 17 studies6,9,11,25,35,40–43,48,51,58,68,77,79,82,84 showed mo derate risk of bias, and 15 studies8,36,39,44,46,54,65,72,87,
88,90–92,95,97 were considered to have a high risk of bias. Furthermore, 2737,38,45,47,49,50,55–57,59,61,63,64,66,67,69,
73,75,76,80,81,85,86,89,93,94,96 non-RCTs were assessed ac-cording to the parameter described in the Newcastle-Ottawa Scale.33 The results of the assessments are illustrated in Appendix Table 3. The score obtained was 6.39 (SD: 1.7) showing a satisfactory (low-medium risk of bias) methodologic level of evidence.
Implant Location and CharacteristicsIn all the included articles, implants were placed in the posterior region, and in all of them, the presence of opposing functional dentition was required. In articles where some of the implants met the inclusion criteria and others did not, only that part of the implants was included in the analysis. All the included articles and implants are listed in Appendix Table 4. Furthermore, the numbers of included implants according to their length are shown in Table 1.
Overall, a total of 4,525 implants were placed; 1,006 were inserted in the maxilla, 2,048 in the man-dible, and in 1,471, the arch was not specified. Screw-retained implant restorations were used 839 times, cement-retained 2,450 times, and in 1,236 implants, the type of retention was not specified. In terms of implant-abutment connection, 718 implants had an external connection, 3,012 presented with an internal connection, and in 795, the type of connection was
Some authors worked in both arches and did not specify how many implants were located in each one. Max = maxilla; mand = mandible; N/A = not available.
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impossible to assess. Furthermore, in 1,722 implants, the abutment was placed in concomitance with their placement, while in 1,888, the two-stage approach was used, and in 915, the type of approach was not clarified. Finally, 1,337 implants were splinted, 1,399 were nonsplinted, and in 1,789, the type of restoration was impossible to evaluate.
Effect of the Length on Overall SurvivalA bias that needed to be ruled out since it could poten-tially condition the survival was the possible associa-tion in terms of time between longer implants (more or less follow-up) compared with the shorter implants. The results of the meta-regression failed to find a sig-nificant effect of the follow-up time (P = .619).
The length of the implant suggested a certain in-fluence on the survival rate (P = .056) since for each additional 1 mm of length, the rate raised by 0.42 percentage points. Hence, placing an implant with a length of 2.5 mm higher than another will increase sur-vival by 1.05 percentage points (Figs 2a and 2b).
Furthermore, for the same length of implant, the level (STL vs BL) (P = .973), the arch (maxilla or man-dible) (P = .667), early or delayed loading (P = .702), the diameter (P = .789), the type of connection (internal or external) (P = .574), the type of retention (screwed or cemented) (P = .241), the splinting (P = .090), and the stage (I or II) (P = .875) did not significantly influence the survival rate.
Effect of Length on the Survival Rate in the MandibleThe survival rates of 2,048 implants were studied in the mandible. The measure of the overall effect of the survival rate was 96.5% with 95% CI (93.9% to 99.1%). Figure 2c shows the influence of the length on the sur-vival. Although the value of the coefficient suggested a small increase in survival as the length of the implant
increases, statistical significance was not reached (P = .389).
None of the studied variables reached statistical sig-nificance, with only the splinting being almost signifi-cant (P = .082). For splinted implants, the survival rate was lower compared with nonsplinted implants.
Effect of Length on the Survival Rate in the MaxillaThe sample comprised 1,006 implants. The measure of the overall survival rate was 97.9% with 95% CI (96.6% to 99.2%). Therefore, the length of the im-plant itself was determining the overall survival rate (P < .001). It has been estimated that an additional 1 mm in length implied 0.68 percentage points more in the rate (Figs 3a and 3b).
Furthermore, some of these variables (retention, stage) have a significant influence on the survival. For the same length of implant, a screw-type retention reduces the survival compared with a cemented one (P = .019), with an impact on it of –2.64%. For the same length of implant, a two-stage approach increases the survival (P = .002) with respect to a one-stage surgical approach by 4.99 percentage points.
Effect of Length on the Overall Early FailureThe early survival rate was 98.7% with 95% CI (97.5% to 99.8%). Implant length was associated with early im-plant survival rate (P = .057). It has been estimated that an additional 1 mm in length implied 0.36 percentage points more in the survival rate (Fig 4). In addition, none of the studied variables were detected to affect the early survival rate.
In the mandible, the early survival rate was 98.1% with 95% CI (95.7% to 100%). The length did not affect short-term survival (P = .261), and none of the studied factors were shown to be statistically significant. In the maxilla, the early survival rate was 99.7% with 95% CI
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Fig 2 (a) Survival rate (in proportion) as a function of implant length in both arches. Regression line for predicted effects and 95% confidence intervals. (b) Survival rate (in proportion) as a function of implant length in both arches including studies with rate > 0.90 (zoom of Fig 2a). Regression line for predicted effects and 95% confidence intervals. (c) Survival rate (in proportion) as a function of implant length in the mandible. Regression line for predicted effects and 95% confidence intervals.
(99.4% to 99.9%). In this case, the length of the implant was important to explain the early implant survival rate (P = .014) since it increased by 0.12% for each ad-ditional 1 mm of length.
Effect of Length on the Survival in the Period Between 3 and 5 YearsA total of 1,306 implants presented a follow-up and information of the failure rate beyond 3 years. The sur-vival rate in the 3- to 5-year period was 96.6% with 95% CI (94.7% to 98.5%). The length showed a statistically significant influence on the survival rate (P = .009). In fact, for every 1 mm more in length, the average sur-vival rate rose by 0.79 percentage points (Fig 5).
In the mandible, 463 implants were entered in the analyses. The survival rate in the 3- to 5-year pe-riod was 97.3% with 95% CI (95.0% to 99.6%). In this case, the length had no special influence on the im-plant survival rate. In the maxilla, 363 implants were entered in the analyses. The survival rate in the 3- to 5-year period was 93.7% with 95% CI (88.5% to 99.0%). The implant length did significantly impact (P = .018) the implant survival rate with 1 additional mm being equivalent to 2 percentage points of increase in the survival rate.
DISCUSSION
Successful rehabilitation of an atrophied maxilla and/or mandible via surgical/prosthetic approaches is a de-manding experience not only for patients but also for clinicians.99,100 Seeking a minimally invasive approach without involving major surgical procedures has been the preferred choice for both parties.7,101
Based on the 66 clinical trials with a sample of 4,525 implants included in this review, the present results demonstrate that longer implants present a signifi-cantly greater overall survival rate than shorter im-plants. This effect is more obvious for implants placed in the maxilla, where each additional millimeter in im-plant length increased the survival rate by 0.68% dur-ing a 5-year follow-up period. Another notable effect was observed when analyzing the effect of implant length on the early (3 to 5 years) survival of implants placed in the maxilla. In this case, each additional mil-limeter in implant length increased implant survival by 2%. Another associated variable of statistical and clini-cal significance was the time of implant loading, where longer implants had better survival rates with late compared to early loading (P < .02). Other than that, for implants with similar lengths, the implant diameter,
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Fig 3 (a) Survival rate (in proportion) as a function of implant length in the maxilla. Regression line for predicted effects and 95% confidence intervals. (b) Survival rate (in proportion) as a function of implant length in the maxilla including studies with rate > 0.90 (zoom of Fig 3a). Regression line for predicted effects and 95% confi-dence intervals.
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Fig 4 (a) Survival rate (in proportion) for early failures as a function of implant length in both arches. Regression line for predicted effects and 95% confidence intervals. (b) Survival rate (in proportion) for early failures as a function of implant length in both arches including studies with rate > 0.90 (zoom of Fig 4a). Regression line for predicted effects and 95% confidence intervals.
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Fig 5 Survival rate (in proportion) for fail-ures between 3 and 5 years as a function of implant length in both arches including studies with rate > 0.90. Regression line for predicted effects and 95% confidence intervals.
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implant location (maxilla vs mandible), splinting adja-cent implants, or type of implant-abutment connection had no influence on implant survival. Unfortunately, it has not been possible to perform an analysis including implants with 5 years minimum of baseline due to the limited sample size.
The present study aimed to provide a true repre-sentation of the clinical performance of short implants. To limit bias against short implants, the present study excluded studies using machined surfaces, or implants placed in the anterior region, which have both proved to induce lower success rates for short implants.16,102 To the best of the authors’ knowledge, no previous system-atic review has attempted to investigate the effect of length on implant survival in nonaugmented sites only, which several clinical studies have explored.42,47,48,70 Though, there are a few systematic reviews that can be compared to the present study, all complementing the results of the present study in one way or another.
In a systematic review, Nisand and Renouard (2014) investigated the impact of implant length and diam-eter on implant survival,12 though they had compared rough- to machined-surface implants, and included both augmented and nonaugmented sites. The authors of that study concluded that survival of short implants might be as good as longer ones. While some of their included studies reported comparable results, many others concluded that longer implants had better sur-vival rates. The authors justified this by pointing to some studies having used short implants with a machined surface. Rough-surface implants have long been dem-onstrated to have superior bone-to-implant contact compared with their smooth-surface counterparts. This was proven in both animal103 and human studies.104 In turn, such histologic findings were portrayed clini-cally as significantly higher survival and success rates of rough- vs machined-surface short implants.16,102 Hence, the present study resorted to exclusion criteria that eliminated any study utilizing machined-surface implants. Generally, higher failure rates in low-density bone have been reported repeatedly in the literature. A recent systematic review found that the cumulative sur-vival rate of implants placed in type I bone was 97.6%, compared with 88.8% for type IV bone.105 When com-paring short to long implants, though, the odds of fail-ure for short implants were nearly twice those of long implants.102
What all the aforementioned studies illuminated is the mere impact of poor bone density as well as aug-mented sites on implant survival. Generally, implant length and surface structure seem to play a great role in increasing implant survival. The perception that there is no difference in survival rates has been mainly based on studies comparing short to long implants, where the latter are placed in augmented bone.3 In
the conclusion of a recent meta-analysis published by the present group of authors, it has been stated that extra-short implants (≤ 6 mm) presented as an equivalent option in the treatment of patients with an atrophic posterior arch up to 3 years follow-up. The word atrophic is important because in most of the in-cluded articles, the longer implants were placed after bone augmentation (sinus elevation or vertical guided bone regeneration). A careful reading shows that at 5 years follow-up, it was possible to include only two articles that placed long implants in native bone11,68 and a third article43 in which bone augmentation (si-nus elevation) was performed only when indicated. Although there was a small sample size, the results of the meta-analysis showed that short implants had a lower survival rate than the longer implants placed in native bone.
A reciprocal bias is noticed when implants placed in augmented sites also have a machined surface. In aug-mented sites, machined-surface implants have proven to have a significantly lower survival rate (86.3%) com-pared with rough surface (96.7%).106 In essence, these studies might have been comparing implant surface as well as implant length.
The present study does not generate unexpected perspectives on this topic. Although longer implants have been previously reported to generally have high-er survival rates,107,108 the present verdict is clearly not to place them unquestionably in any situation. The present authors are being inquisitive about the ben-efit of placing shorter implants when sufficient pris-tine bone is available for regular implants, especially after concluding the results of the present study. Based on the results of the present study, placing a 10-mm implant in the maxilla will immensely increase its 3- to 5-year survival rate by 8% compared with a 6-mm implant. Although higher failure rates should be ex-pected from short implants in low bone density condi-tions, failure of short implants should be compared to the morbidity and failure rates associated with com-plex augmentation procedures to be done in order to place a longer one. Both risks must be gauged before performing either procedure, with the patient actively involved in that decision.109
Another premise that should be evoked is the fate of shorter vs longer implants in the case of advanced peri-implant disease. A cross-sectional study by Derks and coworkers (2016) examined 427 implant patients to find a 45% prevalence of peri-implantitis, with 10% having > 3 mm bone loss.110 Consequently, it would be expected for 10% of patients with 6-mm implants to exhibit bone loss up to the equivalent of 50% of their implant length when peri-implantitis ensues, which puts these implants at a significantly higher risk of failure. On the other hand, if a short implant demands
removal following disease beyond correction, it can be removed fairly easily compared with a longer implant (where the removal may jeopardize adjacent teeth). This generally deems shorter implants as an appeal-ing alternative, irrespective of the risk of failure if ad-vanced peri-implantitis emerges.12
Data from the present study seem remarkable at first glance; however, it must be interpreted with cau-tion without generalizing to every clinical scenario. Therefore, the limitations of the present study need to be characterized and taken into consideration, in addition to the inherent biases of the included stud-ies (Appendix Tables 2 and 3). The present review only investigated what is currently found in the literature; thus, even prior to initiating the literature search, an el-ement of publication bias was present. This might have been inconveniently reflected in the present results and may account for an overestimation of the survival rates pertaining to the longer implants. More particu-lar to the present study is that one of the exclusion cri-teria was implants placed in augmented sites. Such an exclusion was explicitly essential from study inception. The main objective of the present study was to investi-gate the impact of length (as a continuous variable) on implant survival rate, and not a binary comparison of short vs long implants. After the present results were demonstrated, it would be sensible to investigate the impact of different implant lengths placed explicitly in augmented sites (eg, following sinus floor elevation).
CONCLUSIONS
Since choosing the ideal implant length is a daily deci-sion a clinician needs to make, a clear understanding of indications per each situation is fundamental. When abundant native bone exists, placement of longer/reg-ular-sized implants should be chosen over placement of short implants in the maxilla. However, in a posterior mandible, short implants offer a judicious alternative.
ACKNOWLEDGMENTS
The authors reported no conflicts of interest related to this study.
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18. Telleman G, Raghoebar GM, Vissink A, den Hartog L, Huddleston Slater JJ, Meijer HJ. A systematic review of the prognosis of short (<10 mm) dental implants placed in the partially edentulous patient. J Clin Periodontol 2011;38:667–676.
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23. Lee SA, Lee CT, Fu MM, Elmisalati W, Chuang SK. Systematic review and meta-analysis of randomized controlled trials for the man-agement of limited vertical height in the posterior region: Short implants (5 to 8 mm) vs longer implants (> 8 mm) in vertically augmented sites. Int J Oral Maxillofac Implants 2014;29:1085–1097.
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25. Al-Hashedi AA, Taiyeb Ali TB, Yunus N. Short dental implants: An emerging concept in implant treatment. Quintessence Int 2014;45:499–514.
26. Mezzomo LA, Miller R, Triches D, Alonso F, Shinkai RS. Meta-analy-sis of single crowns supported by short (<10 mm) implants in the posterior region. J Clin Periodontol 2014;41:191–213.
27. Lemos CA, Ferro-Alves ML, Okamoto R, Mendonça MR, Pellizzer EP. Short dental implants versus standard dental implants placed in the posterior jaws: A systematic review and meta-analysis. J Dent 2016;47:8–17.
28. Nisand D, Picard N, Rocchietta I. Short implants compared to implants in vertically augmented bone: A systematic review. Clin Oral Implants Res 2015;26(suppl 11):170–179.
29. Khouly I, Veitz-Keenan A. Insufficient evidence for sinus lifts over short implants for dental implant rehabilitation. Evid Based Dent 2015;16:21–22.
30. Alqutaibi AY, Altaib F. Short dental implant is considered as a reli-able treatment option for patients with atrophic posterior maxilla. J Evid Based Dent Pract 2016;16:173–175.
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36. Hadzik J, Krawiec M, Kubasiewicz-Ross P, Prylińska-Czyżewska A, Gedrange T, Dominiak M. Short implants and conventional implants in the residual maxillary alveolar ridge: A 36-month follow-up observation. Med Sci Monit 2018;24:5645–5652.
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55. Lee PK, Siu AS. A two-year evaluation of a sloped marginal contour implant system placed in healed sites. Int J Oral Maxillofac Im-plants 2016;31:1423–1428.
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65. Nedir R, Nurdin N, Khoury P, Bischof M. Short implants placed with or without grafting in atrophic sinuses: The 3-year results of a prospective randomized controlled study. Clin Implant Dent Relat Res 2016;18:10–18.
66. Slotte C, Grønningsaeter A, Halmøy AM, et al. Four-millimeter-long posterior-mandible implants: 5-year outcomes of a prospective multicenter study. Clin Implant Dent Relat Res 2015;17(suppl 2):e385–e395.
67. Rossi F, Lang NP, Ricci E, Ferraioli L, Marchetti C, Botticelli D. Early loading of 6-mm-short implants with a moderately rough surface supporting single crowns—a prospective 5-year cohort study. Clin Oral Implants Res 2015;26:471–477.
68. Romeo E, Storelli S, Casano G, Scanferla M, Botticelli D. Six-mm versus 10-mm long implants in the rehabilitation of posterior edentulous jaws: A 5-year follow-up of a randomised controlled trial. Eur J Oral Implantol 2014;7:371–381.
69. Bratu E, Chan HL, Mihali S, et al. Implant survival rate and marginal bone loss of 6-mm short implants: A 2-year clinical report. Int J Oral Maxillofac Implants 2014;29:1425–1428.
70. Canullo L, Peñarrocha D, Peñarrocha M, Rocio AG, Peñarrocha-Diago M. Piezoelectric vs. conventional drilling in implant site preparation: Pilot controlled randomized clinical trial with cross-over design. Clin Oral Implants Res 2014;25:1336–1343.
71. Pozzi A, Tallarico M, Moy PK. Three-year post-loading results of a randomised, controlled, split-mouth trial comparing implants with different prosthetic interfaces and design in partially posterior edentulous mandibles. Eur J Oral Implantol 2014;7:47–61.
72. Kim YK, Lee JH, Lee JY, Yi YJ. A randomized controlled clinical trial of two types of tapered implants on immediate loading in the posterior maxilla and mandible. Int J Oral Maxillofac Implants 2013;28:1602–1611.
73. Mangano FG, Shibli JA, Sammons RL, Iaculli F, Piattelli A, Mangano C. Short (8-mm) locking-taper implants supporting single crowns in posterior region: A prospective clinical study with 1-to 10-years of follow-up. Clin Oral Implants Res 2014;25:933–940.
74. Telleman G, Meijer HJ, Vissink A, Raghoebar GM. Short implants with a nanometer-sized CaP surface provided with either a platform-switched or platform-matched abutment connection in the posterior region: A randomized clinical trial. Clin Oral Implants Res 2013;24:1316–1324.
75. Kennedy KS, Jones EM, Kim DG, McGlumphy EA, Clelland NL. A prospective clinical study to evaluate early success of short implants. Int J Oral Maxillofac Implants 2013;28:170–177.
76. Pieri F, Aldini NN, Fini M, Marchetti C, Corinaldesi G. Preliminary 2-year report on treatment outcomes for 6-mm-long implants in posterior atrophic mandibles. Int J Prosthodont 2012;25:279–289.
77. Canullo L, Iannello G, Peñarrocha M, Garcia B. Impact of implant diameter on bone level changes around platform switched implants: Preliminary results of 18 months follow-up a prospective randomized match-paired controlled trial. Clin Oral Implants Res 2012;23:1142–1146.
78. Meloni SM, De Riu G, Pisano M, De Riu N, Tullio A. Immediate versus delayed loading of single mandibular molars. One-year results from a randomised controlled trial. Eur J Oral Implantol 2012;5:345–353.
79. Barewal RM, Stanford C, Weesner TC. A randomized controlled clinical trial comparing the effects of three loading proto-cols on dental implant stability. Int J Oral Maxillofac Implants 2012;27:945–956.
80. Enkling N, Jöhren P, Klimberg V, Bayer S, Mericske-Stern R, Jepsen S. Effect of platform switching on peri-implant bone levels: A randomized clinical trial. Clin Oral Implants Res 2011;22:1185–1192.
81. Alghamdi H, Anand PS, Anil S. Undersized implant site preparation to enhance primary implant stability in poor bone density: A pro-spective clinical study. J Oral Maxillofac Surg 2011;69:e506–e512.
82. Felice P, Pellegrino G, Checchi L, Pistilli R, Esposito M. Vertical augmentation with interpositional blocks of anorganic bovine bone vs. 7-mm-long implants in posterior mandibles: 1-year results of a randomized clinical trial. Clin Oral Implants Res 2010;21:1394–1403.
83. Payer M, Heschl A, Wimmer G, Wegscheider W, Kirmeier R, Loren-zoni M. Immediate provisional restoration of screw-type implants in the posterior mandible: Results after 5 years of clinical function. Clin Oral Implants Res 2010;21:815–821.
84. Park JC, Ha SR, Kim SM, Kim MJ, Lee JB, Lee JH. A randomized clinical 1-year trial comparing two types of non-submerged dental implants. Clin Oral Implants Res 2010;21:228–236.
85. MacDonald K, Pharoah M, Todescan R, Deporter D. Use of sintered porous-surfaced dental implants to restore single teeth in the maxilla: A 7- to 9-year follow-up. Int J Periodontics Restorative Dent 2009;29:191–199.
86. Vigolo P, Givani A. Platform-switched restorations on wide-diam-eter implants: A 5-year clinical prospective study. Int J Oral Maxillo-fac Implants 2009;24:103–109.
87. Roccuzzo M, Aglietta M, Bunino M, Bonino L. Early loading of sandblasted and acid-etched implants: A randomized-controlled double-blind split-mouth study. Five-year results. Clin Oral Im-plants Res 2008;19:148–152.
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89. Achilli A, Tura F, Euwe E. Immediate/early function with tapered implants supporting maxillary and mandibular posterior fixed partial dentures: Preliminary results of a prospective multicenter study. J Prosthet Dent 2007;97(suppl 6):s52–s58.
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Early loading of implants in the atrophic posterior maxilla: lateral sinus lift with autogenous bone and Bio-Ossversus crestal mini sinus lift and 8-mm hydroxyapatite-coated implants. A randomised controlled clinical trial
More recent publication (Cannizzaro et al 2015)
Sahrmann et al (2016)
Success of 6-mm Implants with Single-Tooth Restorations: A 3-year Randomized Controlled Clinical Trial
More recent publication (Naenni et al2018)
Pistilli et al (2013)
Posterior atrophic jaws rehabilitated with prostheses supported by 6 mm long 4 mm wide implants or by longer implants in augmented bone. One-year post-loading results from a pilot randomised controlled trial
More recent publication (Felice 2018)
Gulje et al (2013) Implants of 6 mm vs. 11 mm lengths in the posterior maxilla and mandible: a 1-year multicenter randomized controlled trial
More recent publication (Zadeh 2018)
Felice et al (2015)
Short implants as an alternative to crestal sinus lift: A 1-year multicentre randomised controlled trial More recent publication (Gastaldi 2017)
Pistilli et al (2013)
Posterior atrophic jaws rehabilitated with prostheses supported by 5 x 5 mm implants with a novel nanostructured calcium-incorporated titanium surface or by longer implants in augmented bone. One-year results from a randomised controlled trial
More recent publication (Gastaldi 2018)
Han et al (2016) A prospective, multicenter study assessing the DENTSPLY Implants, OsseoSpeed() TX, length 6 mm in the posterior maxilla and mandible: a 1-year follow-up study.
More recent publication (Han et al 2018)
Lindh et al (2001) Implant versus tooth-implant supported prostheses in the posterior maxilla: a 2-year report Implants splinted with teeth
Wagner et al (2018)
Fiber-Reinforced Resin Fixed Prostheses on 4 Short Implants in Severely Atrophic Maxillas: 1-Year Results of a Prospective Cohort Study.
Specific length was not reported
Willer et al (2003)
Survival rate of IMZ implants: A prospective 10-year analysis. Specific length was not reported
Deporter et al (1999)
Five- to six-year results of a prospective clinical trial using the ENDOPORE dental implant and a mandibular overdenture
Specific length was not reported
Romeo et al (2002)
Long-term clinical effectiveness of oral implants in the treatment of partial edentulism Specific length was not reported
Cesaretti et al (2016)
Radiographic evaluation of immediately loaded implants supporting 2-3 units fixed bridges in the posterior maxilla: a 3-year follow-up prospective randomized controlled multicenter clinical study
Specific length was not reported
Chidagam et al (2017)
Immediate versus delayed loading of implant for replacement of missing mandibular first molar: A randomized prospective six years clinical study
Specific length was not reported
Moberg et al (2001)
Brånemark System and ITI Dental Implant System for treatment of mandibular edentulism. A comparative randomized study: 3-year follow-up
Specific length was not reported
McGlumphy et al (2003)
Prospective study of 429 hydroxyapatite-coated cylindric omniloc implants placed in 121 patients Specific length was not reported
Lekholm et al (1999)
Survival of the Brånemark implant in partially edentulous jaws Specific length was not reported
Cecchinato et al (2004)
Submerged or non-submerged healing of endosseous implants to be used in the rehabilitation of partially dentate patients
Specific length was not reported
Jeong et al (2011)
A 1-year prospective clinical study of soft tissue conditions and marginal bone changes around dental implants after flapless implant surgery
Specific length was not reported
Lang et al (2007) Immediate implant placement with transmucosal healing in areas of aesthetic priority. A multicentre randomized-controlled clinical trial I. Surgical outcomes
Specific length was not reported
Larsson et al (2016)
Ten-Year Follow-Up of Implant-Supported All-Ceramic Fixed Dental Prostheses: A Randomized, Prospective Clinical Trial
Specific length was not reported
Lee et al (2009) Effects of flapless implant surgery on soft tissue profiles: a prospective clinical study Specific length was not reported
Lee et al (2007) Effect of microthread on the maintenance of marginal bone level: a 3-year prospective study Specific length was not reported
Borg et al (2014) Titanium- and zirconia-based implant-supported fixed dental prostheses. A randomized, prospective clinical pilot study
Specific length was not reported
Brandenberg et al (2017)
Randomized controlled clinical pilot study of all-ceramic single-tooth implant reconstructions: clinical and microbiological outcomes at one year of loading
Specific length was not reported
Karoussis et al (2004)
Effect of implant design on survival and success rates of titanium oral implants: a 10-year prospective cohort study of the ITI Dental Implant System
Specific length was not reported
Kemppainen et al (1997)
A comparative prospective clinical study of two single-tooth implants: a preliminary report of 102 implants
Specific length was not reported
Kim et al (2015) Prospective, 1-year observational study of double-threaded tapered body dental implants with immediate loading
Specific length was not reported
Jokstad et al (2014)
Immediate function on the day of surgery compared with a delayed implant loading process in the mandible: a randomized clinical trial over 5 years
The International Journal of Oral & Maxillofacial Implants 1369b
Appendix Table 1 List of Excluded Articles
Author TitleReason for exclusion
Jones et al (1999)
A 5-year comparison of hydroxyapatite-coated titanium plasma–sprayed and titanium plasma–sprayed cylinder dental implants
Specific length was not reported
Kesteren et al (2010)
A prospective randomized clinical study of changes in soft tissue position following immediate and delayed implant placement
Specific length was not reported
Blanco et al (2018)
Effect of abutment height on interproximal implant bone level in the early healing: A randomized clinical trial
Specific length was not reported
Kyriazis et al (2012)
Crestal bone resorption after the application of two periodontal surgical techniques: a randomized, controlled clinical trial
Specific length was not reported
Karabuda et al (2011)
Stability, marginal bone loss and survival of standard and modified sand-blasted, acid-etched implants in bilateral edentulous spaces: a prospective 15-month evaluation
Specific length was not reported
Khang et al (2001)
A multi-center study comparing dual acid-etched and machined-surfaced implants in various bone qualities
Specific length was not reported
Ma et al (2010) Marginal bone loss with mandibular two-implant overdentures using different loading protocols and attachment systems: 10-year outcomes
Specific length was not reported
MacDonald et al (2001)
Physicochemical study of plasma-sprayed hydroxypatite-coated implants in humans Specific length was not reported
Maiorana et al (2015)
A Four-Year Survival Rate Multicenter Prospective Clinical Study on 377 Implants: Correlations Between Implant Insertion Torque, Diameter, and Bone Quality
Specific length was not reported
Mangano et al (2008)
Single-tooth Morse taper connection implants after 1 year of functional loading: a multicentre study on 302 patients
Specific length was not reported
Mangano et al (2018)
Full in-Office Guided Surgery with Open Selective Tooth-Supported Templates: A Prospective Clinical Study on 20 Patients
Specific length was not reported
Lee et al (2016) A Long-Term Prospective Evaluation of Marginal Bone Level Change Around Different Implant Systems Specific length was not reported
Levin et al (2006) Long-term success of implants replacing a single molar Specific length was not reported
Liddelow et al (2010)
The immediately loaded single implant-retained mandibular overdenture: a 36-month prospective study Does not mention failure timing
Lindeboom et al (2010)
A comparison of two implant techniques on patient-based outcome measures: a report of flapless vs. conventional flapped implant placement
Specific length was not reported
Linkevicius et al (2015)
Crestal Bone Stability around Implants with Horizontally Matching Connection after Soft Tissue Thickening: A Prospective Clinical Trial
Specific length was not reported
Nimwegen et al (2015)
Treatment Outcome of Two Adjacent Implant-Supported Restorations with Different Implant Platform Designs in the Esthetic Region: a Five-Year Randomized Clinical Trial
Specific length was not reported
Nicu et al (2012) RCT comparing implants with turned and anodically oxidized surfaces: a pilot study, a 3-year follow-up Specific length was not reported
Naert et al (1997)
A randomised clinical trial on the influence of splinted and unsplinted oral implants in mandibular overdenture therapy. A 3-year report
Specific length was not reported
Murphy et al (2002)
A prospective 5-year study of two cast framework alloys for fixed implant-supported mandibular prostheses
Specific length was not reported
Moberg et al (2001)
Brånemark System and ITI Dental Implant System for treatment of mandibular edentulism. A comparative randomized study: 3-year follow-up
Specific length was not reported
Francesco et al (2017)
Clinical and radiographic evaluation of single tantalum dental implants: a prospective pilot clinical study
Specific length was not reported
Mitsias et al (2018)
Immediate, early (6 weeks) and delayed loading (3 months) of single, partial and full fixed implant supported prostheses: 1-year post-loading data from a multicentre randomised controlled trial
Specific length was not reported
Mohanty et al (2018)
Risk Assessment in Long-term Survival Rates of Dental Implants: A Prospective Clinical Study Specific length was not reported
Moheng et al (2005)
Clinical and biologic factors related to oral implant failure: a 2-year follow-up study Specific length was not reported
Morris et al (2001)
A 48-month multicentric clinical investigation: implant design and survival Specific length was not reported
Morris et al (1997)
Success of multiple endosseous dental implant designs to second-stage surgery across study sites Specific length was not reported
Nicolau et al (2013)
Immediate and early loading of chemically modified implants in posterior jaws: 3-year results from a prospective randomized multicenter study
Specific length was not reported
Nicu et al (2012) RCT comparing implants with turned and anodically oxidized surfaces: a pilot study, a 3-year follow-up Specific length was not reported
Mau et al (2002) Randomized multicenter comparison of two coatings of intramobile cylinder implants in 313 partially edentulous mandibles followed up for 5 years
Guided implant surgery after free-flap reconstruction: Four-year results from a prospective clinical trial Specific length was not reported
Merli et al (2012) Immediate versus early non-occlusal loading of dental implants placed flapless in partially edentulous patients: a 3-year randomized clinical trial
Specific length was not reported
Negri et al (2014) The effect of age, gender, and insertion site on marginal bone loss around endosseous implants: results from a 3-year trial with premium implant system
Specific length was not reported
Ferrigno et al (2006)
Dental implants placement in conjunction with osteotome sinus floor elevation: A 12-year life-table analysis from a prospective study on 588 ITI implants
Specific length was not reported
Mumcu et al (2012)
The influence of healing type on marginal bone levels of implants supporting mandibular overdentures: a randomized clinical study
Specific length was not reported
Cannata et al (2017)
A comparison of two implants with conical vs internal hex connections: 1-year post-loading results from a multicentre, randomised controlled trial
Specific length was not reported
Nagarajan et al (2015)
Evaluation of Crestal Bone Loss Around Implants Placed at Equicrestal and Subcrestal Levels Before Loading: A Prospective Clinical Study
Specific length was not reported
Andersson et al (2003)
Ceramic implant abutments for short-span fpds: a prospective 5-year multicenter study. Specific length was not reported
Andersson et al (2001)
Alumina ceramic implant abutments used for single-tooth replacement: a prospective 1- to 3-year multicenter study.
Specific length was not reported
Gallucci et al (2011)
Esthetic outcomes with porcelain-fused-to-ceramic and all-ceramic single-implant crowns: a randomized clinica trial
Implant heights were not reported
Assche et al (2012)
RCT comparing minimally with moderately rough implants. Part 1: clinical observations Implant heights were not reported
Assche et al (2011)
Microbiological outcome of two screw-shaped titanium implant systems placed following a split-mouth randomised protocol, at the 12th year of follow-up after loading
Specific length was not reported
Astrand et al (2003)
Tapered implants in jaws with soft bone quality: a clinical and radiographic 1-year study of the Brånemark System Mark IV fixture
Specific length was not reported
Bornstein et al (2005)
Early loading of non-submerged titanium implants with a sandblasted and acid-etched surface. 5-year results of a prospective study in partially edentulous patients
Specific length was not reported
Abduo et al (2017)
A comparative study of encode protocol versus conventional protocol for restoring single implants: One-year prospective randomized controlled clinical trial
Specific length was not reported
Cappiello et al (2008)
Evaluation of peri-implant bone loss around platform-switched implants. Specific length was not reported
Hürzeler et al (2007)
Peri-implant bone level around implants with platform-switched abutments: Preliminary data from a prospective study.
Specific length was not reported
Trammell et al (2009)
A prospective, randomized, controlled comparison of platform-switched and matched-abutment implants in short-span partial denture situations
Specific length was not reported
Vigolo et al (2009)
Platform-switched restorations on wide-diameter implants: A 5-year clinical prospective study Specific length was not reported
Roccuzzo et al (2012)
Ten-year results of a three arms prospective cohort study on implants in periodontally compromised patients. Part 2: clinical results.
Specific length was not reported
Nikzad et al (2010)
Custom-made radiographic template, computed tomography, and computer-assisted flapless surgery for treatment planning in partial edentulous patients: a prospective 12-month study
Specific length was not reported
Nimwegen et al (2015)
Treatment Outcome of Two Adjacent Implant-Supported Restorations with Different Implant Platform Designs in the Esthetic Region: a Five-Year Randomized Clinical Trial
Specific length was not reported
Nkenke et al (2007)
Patient-centred outcomes comparing transmucosal implant placement with an open approach in the maxilla: a prospective, non-randomized pilot study
Specific length was not reported
Prati et al (2016) A 3-Year Prospective Cohort Study on 132 Calcium Phosphate-Blasted Implants: Flap vs Flapless Technique
Specific length was not reported
Thoma et al (2016)
Randomized Controlled Clinical Trial of All-Ceramic Single Tooth Implant Reconstructions Using Modified Zirconia Abutments: radiographic and Prosthetic Results at 1 Year of Loading
Specific length was not reported
Thoma et al (2014)
Prospective randomized controlled clinical study comparing two dental implant systems: demographic and radiographic results at one year of loading
Specific length was not reported
Trammell et al (2009)
A prospective, randomized, controlled comparison of platform-switched and matched-abutment implants in short-span partial denture situations
Specific length was not reported
Ozkan et al (2007)
Three-year treatment outcomes with three brands of implants placed in the posterior maxilla and mandible of partially edentulous patients
Specific length was not reported
Zembic et al (2013)
Five-year results of a randomized controlled clinical trial comparing zirconia and titanium abutments supporting single-implant crowns in canine and posterior regions
Specific length was not reported
Zetterqvist et al (2010)
A prospective, multicenter, randomized-controlled 5-year study of hybrid and fully etched implants for the incidence of peri-implantitis
The International Journal of Oral & Maxillofacial Implants 1369d
Appendix Table 1 List of Excluded Articles
Author TitleReason for exclusion
Willer et al (2003)
Survival rate of IMZ implants: a prospective 10-year analysis Specific length was not reported
Wittneben et al (2017)
Esthetic and Clinical Performance of Implant-Supported All-Ceramic Crowns Made with Prefabricated or CAD/CAM Zirconia Abutments: a Randomized, Multicenter Clinical Trial
Specific length was not reported
Yi et al (2001) Implant-supported fixed prostheses for the rehabilitation of periodontally compromised dentitions: a 3-year prospective clinical study
Specific length was not reported
Tsoukaki et al (2013)
Clinical, radiographic, microbiological, and immunological outcomes of flapped vs. flapless dental implants: a prospective randomized controlled clinical trial
Specific length was not reported
Tunchel et al (2016)
3D Printing/Additive Manufacturing Single Titanium Dental Implants: A Prospective Multicenter Study with 3 Years of Follow-Up
Specific length was not reported
Wannfors et al (1999)
A prospective clinical evaluation of different single-tooth restoration designs on osseointegrated implants. A 3-year follow-up of Brånemark implants
Specific length was not reported
Rocha et al (2016)
Effect of platform switching on crestal bone levels around implants in the posterior mandible: 3 years results from a multicentre randomized clinical trial
Specific length was not reported
Sanchez-Siles et al (2016)
Crestal bone loss around submerged and non-submerged implants during the osseointegration phase with different healing abutment designs: a randomized prospective clinical study
Specific length was not reported
Schätzle et al (2009)
Stability change of chemically modified sandblasted/acid-etched titanium palatal implants. A randomized-controlled clinical trial
Specific length was not reported
Piek et al (2013) One-year survival rate outcomes of innovative dental implants: a prospective clinical study Specific length was not reported
Schliephake et al (2012)
Early loading of surface modified implants in the posterior mandible - 5 year results of an open prospective non-controlled study
Specific length was not reported
Olsson et al (1995)
MkII- -a modified self-tapping Brånemark implant: 3-year results of a controlled prospective pilot study Specific length was not reported
Sunitha et al (2013)
Flapless implant surgery: a 2-year follow-up study of 40 implants Specific length was not reported
Tallarico et al (2011)
Clinical and radiological outcomes of 1- versus 2-stage implant placement: 1-year results of a randomised clinical trial
Specific length was not reported
Tallarico et al (2011)
A prospective case-control clinical trial comparing 1- and 2-stage Nobel Biocare TiUnite implants: resonance frequency analysis assessed by Osstell Mentor during integration
Specific length was not reported
Rodriguez et al (2000)
Survival of various implant-supported prosthesis designs following 36 months of clinical function Specific length was not reported
Van Nimwegen et al (2015)
Treatment Outcome of Two Adjacent Implant-Supported Restorations with Different Implant Platform Designs in the Esthetic Region: A Five-Year Randomized Clinical Trial
Specific length was not reported
Nordin et al (2004)
A 3-arm study of early loading of rough-surfaced implants in the completely edentulous maxilla and in the edentulous posterior maxilla and mandible: Results after 1 year of loading
Specific length was not reported
Schropp et al (2014)
Early, delayed, or late single implant placement: 10-year results from a randomized controlled clinical trial
Specific length was not reported
Strietzel et al (2007)
Oral rehabilitation using Camlog screw-cylinder implants with a particle-blasted and acid-etched microstructured surface. Results from a prospective study with special consideration of short implants
Specific length was not reported
Tymstra et al (2011)
Dental implant treatment for two adjacent missing teeth in the maxillary aesthetic zone: a comparative pilot study and test of principle
Specific length was not reported
Tealdo et al (2011)
Immediate versus delayed loading of dental implants in edentulous maxillae: a 36-month prospective study
Specific length was not reported
van Steenberghe et al (2000)
A prospective split-mouth comparative study of two screw-shaped self-tapping pure titanium implant systems
Specific length was not reported
O’Brien (2004) A 6-year prospective study of 620 stress-diversion surface (SDS) dental implants Specific length was not reported
Calvo-Guirado et al (2016)
Evaluation of extra short 4-mm implants in mandibular edentulous patients with reduced bone height in comparison with standard implants: a 12-month results
Specific length was not reported
Haas et al (1995) Brånemark single tooth implants: a preliminary report of 76 implants. Specific length was not reported
Henry et al (1997)
Osseointegrated implants for single-tooth replacement: A prospective 5- year multicenter study Specific length was not reported
Jemt et al (1998) Customized titanium single-implant abutments: 2-year follow-up pilot study. Specific length was not reported
Degidi et al (2015)
10-year prospective cohort follow-up of immediately restored XiVE implants. Specific length was not reported
Degidi et al (2009)
A comparison between immediate loading and immediate restoration in cases of partial posterior mandibular edentulism: a 3-year randomized clinical trial
Oxidized titanium implants (Nobel Biocare® TiUnite™) compared with turned titanium implants (Nobel Biocare® mark III™) with respect to implant failure in a group of consecutive patients treated with early functional loading and two‐stage protocol
Specific length was not reported
Karabuda et al (2011)
Stability, marginal bone loss and survival of standard and modified sand‐blasted, acid‐etched implants in bilateral edentulous spaces: a prospective 15‐month evaluation
Specific length was not reported
Danny et al (2011)
Clinical and radiographic evaluation of NobelActiveTM dental implants Specific length was not reported
Thilander et al (1999)
Single implants in the upper incisor region and their relationship to the adjacent teeth. An 8-year follow-up study
Specific length was not reported
Pollizi et al (1999)
Clinical application of narrow Brånemark System implants for single-tooth restorations
Specific length was not reported
Scheller et al (1998)
A 5-year multicenter study on implant-supported single crown restorations Specific length was not reported
Lemmerman et al (2005)
Osseointegrated Dental Implants in Private Practice: A Long-Term Case Series Study Specific length was not reported
Wyatt et al (1998)
Treatment Outcomes of Patients With Implant-Supported Fixed Partial Prostheses Specific length was not reported
Buser et al (1997)
Clinical trials on implants in regenerated bone Specific length was not reported
Mangano et al (2009)
Prospective clinical evaluation of 1920 Morse taper connection implants:results after 4 years of functional loading
Specific length was not reported
Gibbard et al (2004)
5-year prospective study of implant-supported single-tooth replacements. Specific length was not reported
Gotfredsen et al (2012)
A 10‐Year Prospective Study of Single Tooth Implants Placed in the Anterior Maxilla Specific length was not reported
Arnhart et al (2012)
Comparison of variable-thread tapered implant designs to a standard tapered implant design after immediate loading. A 3-year multicentre randomised controlled trial
Specific length was not reported
Nikzad et al (2010)
Custom-made radiographic template, computed tomography, and computer-assisted flapless surgery for treatment planning in partial edentulous patients: a prospective 12-month study
Specific length was not reported
Quirynen et al (1992)
Fixture design and overload influence marginal bone loss and fixture success in the Brånemark system.
Specific length was not reported
Vigolo et al (2015)
Clinical evaluation of marginal bone level change around multiple adjacent implants restored with splinted and nonsplinted restorations: a 10-year randomized controlled trial
Specific length was not reported
Cannizzaro et al (2015)
Immediate loading of fixed cross-arch prostheses supported by flapless-placed supershort or long implants: 1-year results from a randomised controlled trial
Specific length was not reported
Taschieri et al (2018)
Short dental implants as compared to maxillary sinus augmentation procedure for the rehabilitation of edentulous posterior maxilla: Three-year results of a randomized clinical study.
Specific length was not reported
Becker et al (2016)
Dental implants in an aged population: evaluation of periodontal health, bone loss, implant survival, and quality of life.
Specific length was not reported
Gotfredsen et al (2012)
A 10-Year Prospective Study of Single Tooth Implants Placed in the Anterior Maxilla Specific length was not reported
Jemt et al (2009) Cemented CeraOne and porcelain fused to TiAdapt abutment single-implant crown restorations: a 10-year comparative follow-up study
Specific length was not reported
Kreissl et al (2007)
Technical complications of implant-supported fixed partial dentures in partially edentulous cases after an average observation period of 5 years
Specific length was not reported
Guerra et al (2014)
Platform switch versus platform match in the posterior mandible – 1-year results of a multicentre randomized clinical trial
Specific length was not reported
Kim et al (2015) Resonance frequency analysis as a predictor of early implant failure in the partially edentulous posterior maxilla following immediate nonfunctional loading or delayed loading with single unit restorations.
Specific length was not reported
Henry et al (1996)
Osseointegrated implants for single-tooth replacement: a prospective 5-year multicenter study Specific length was not reported
Grandi et al (2013)
Immediate provisionalisation of single post-extractive implants versus implants placed in healed sites in the anterior maxilla: 1-year results from a multicentre controlled cohort study.
Specific length was not reported
Piek et al (2013) One-year survival rate outcomes of innovative dental implants: a prospective clinical study. Specific length was not reported
Ganeles et al (2008)
Immediate and early loading of Straumann implants with a chemically modified surface (SLActive) in the posterior mandible and maxilla: 1‐year results from a prospective multicenter study
Specific length was not reported
Schliephake et al (2012)
Early loading of surface modified implants in the posterior mandible - 5 year results of an open prospective non-controlled study.
The International Journal of Oral & Maxillofacial Implants 1369f
Appendix Table 1 List of Excluded Articles
Author TitleReason for exclusion
Nissan et al (2011)
Long-term outcome of cemented versus screw-retained implant-supported partial restorations. Specific length was not reported
Karaky et al (2011)
Antibiotic prophylaxis and early dental implant failure: a quasi-random controlled clinical trial Specific length was not reported
Mangano et al (2012)
Prospective clinical evaluation of 201 direct laser metal forming implants: results from a 1-year multicenter study.
Anterior implants
Mangano et al (2012)
Prospective clinical evaluation of 201 direct laser metal forming implants: results from a 1-year multicenter study
Anterior implants
Arduino et al (2015)
Single preoperative dose of prophylactic amoxicillin versus a 2-day postoperative course in dental implant surgery: A two-centre randomised controlled trial
Specific length was not reported
Ignacio Sanz Martin et al (2015)
Prospective randomized controlled clinical study comparing two dental implant types: volumetric soft tissue changes at 1 year of loading
Specific length was not reported
Nolan et al (2014)
The influence of prophylactic antibiotic administration on post-operative morbidity in dental implant surgery. A prospective double blind randomized controlled clinical trial
Specific length was not reported
Arnhart et al (2012)
Impact of implant surface topography: a clinical study with a mean functional loading time of 85 months
Specific length was not reported
Patel et al (2013) Radiographic and clinical outcomes of implants placed in ridge preserved sites: a 12-month post-loading follow-up.
Specific length was not reported
Sasse et al (2012)
Randomized clinical trial on single retainer all-ceramic resin-bonded fixed partial dentures: Influence of the bonding system after up to 55 months.
Specific length was not reported
Margossian et al (2012)
Immediate loading of mandibular dental implants in partially edentulous patients: a prospective randomized comparative study.
Specific length was not reported
Hosseini et al (2011)
A 1-year randomised controlled trial comparing zirconia versus metal-ceramic implant supported single-tooth restorations.
Specific length was not reported
Al-Nawas et al (2013)
Multicenter randomized clinical trial: early loading of implants in maxillary bone Specific length was not reported
Larsson et al (2010)
Five-year follow-up of implant-supported Y-TZP and ZTA fixed dental prostheses. A randomized, prospective clinical trial comparing two different material systems.
Specific length was not reported
Shibly et al (2012)
Immediate implants with immediate loading vs. conventional loading: 1-year randomized clinical trial Specific length was not reported
Capelli et al (2010)
A 5-year report from a multicentre randomised clinical trial: immediate non-occlusal versus early loading of dental implants in partially edentulous patients.
Specific length was not reported
Esposito et al (2010)
Effectiveness of prophylactic antibiotics at placement of dental implants: a pragmatic multicentre placebo-controlled randomised clinical trial
Specific length was not reported
Luongo et al (2005)
Early loading of sandblasted, acid-etched implants in the posterior maxilla and mandible: a 1-year follow-up report from a multicenter 3-year prospective study.
Specific length was not reported
Anitua E et al (2009)
A multicentre placebo-controlled randomised clinical trial of antibiotic prophylaxis for placement of single dental implants.
Specific length was not reported
Widmark et al (2001)
Rehabilitation of patients with severely resorbed maxillae by means of implants with or without bone grafts: a 3- to 5-year follow-up clinical report.
Specific length was not reported
Baer et al (2013) A 3-year multicenter study of marginal bone level and soft tissue health of a 1-piece implant. Specific length was not reported
Esquivel-Upshaw et al (2013)
Randomized clinical trial of implant-supported ceramic-ceramic and metal-ceramic fixed dental prostheses: preliminary results.
Specific length was not reported
Rocci et al (2013) Immediate loading of Brånemark system TiUnite and machined-surface implants in the posterior mandible, part II: a randomized open-ended 9-year follow-up clinical trial
Specific length was not reported
Cecchinato et al (2008)
Bone level alterations at implants placed in the posterior segments of the dentition: outcome of submerged/non-submerged healing. A 5-year multicenter, randomized, controlled clinical trial
Specific length was not reported
Albrektsson et al (2007)
Survival of NobelDirect implants: an analysis of 550 consecutively placed implants at 18 different clinical centers.
Specific length was not reported
Rocci et al (2003)
Immediate loading of Brånemark System TiUnite and machined-surface implants in the posterior mandible: a randomized open-ended clinical trial
Specific length was not reported
Piao et al (2009) Marginal bone around three different implant systems: radiographic evaluation after 1 year. Specific length was not reported
Cho et al (2004) Screw loosening for standard and wide diameter implants in partially edentulous cases: 3- to 7-year longitudinal data.
Specific length was not reported
Jeffcoat et al (2003)
A comparison of hydroxyapatite (HA) -coated threaded, HA-coated cylindric, and titanium threaded endosseous dental implants.
Radiographic and clinical evaluation of single-tooth Biolok implants: a 5-year study. Specific length was not reported
Astrand et al (2004)
Astra Tech and Brånemark system implants: a 5-year prospective study of marginal bone reactions. Specific length was not reported
Karoussis et al (2004)
Effect of implant design on survival and success rates of titanium oral implants: a 10-year prospective cohort study of the ITI Dental Implant System.
Specific length was not reported
Lambert et al (2000)
The influence of smoking on 3-year clinical success of osseointegrated dental implants. Specific length was not reported
Astrand et al (2002)
Nonsubmerged and submerged implants in the treatment of the partially edentulous maxilla. Specific length was not reported
Misch et al (2006)
Short dental implants in posterior partial edentulism: a multicenter retrospective 6-year case series study.
Retrospective study
Bach et al (2013) Assessment of Short Dental Implants Restored With Single-Unit Nonsplinted Restorations Retrospective study
de Molon et al (2017)
Evaluation of Short and Regular Implants after Prosthesis Placement in the Mandible: A Nonrandomized Controlled Clinical Trial
Retrospective study
Goenè et al (2005)
Performance of short implants in partial restorations: 3-year follow-up of Osseotite implants. Retrospective study
Ortorp et al (2008)
Laser-welded titanium frameworks supported by implants in the partially edentulous mandible: a 10-year comparative follow-up study.
Retrospective study
Jung et al (2008) Evaluation of mandibular posterior single implants with two different surfaces: a 5-year comparative study
Retrospective study
Bischof et al (2006)
A five-year life-table analysis on wideneck ITI implants with prosthetic evaluation and radiographic analysis:results from a private practice
Retrospective study
Khayat et al (2001)
An investigation of 131 consecutively placed wide screw-vent implants. Retrospective study
Widmark et al (2003)
Mk III: a third generation of the self-tapping Brånemark System implant, including the new Stargrip internal grip design. A 1-year prospective four-center study
Complete edentulism cases
Östman et al (2013)
Immediate occlusal loading of NanoTite™ tapered implants: a prospective 1-year clinical and radiographic study.
Complete edentulism cases
Henry et al (2003)
Prospective multicenter study on immediate rehabilitation of edentulous lower jaws according to the Brånemark Novum protocol.
Complete edentulism cases
Sethi et al (2000) The use of angulated abutments in implant dentistry: five-year clinical results of an ongoing prospective study.
Complete edentulism cases
Vroom et al (2009)
Effect of surface topography of screw-shaped titanium implants in humans on clinical and radiographic parameters: a 12-year prospective study.
Complete edentulism cases
Heydenrijk et al (2002)
Two-part implants inserted in a one-stage or a two-stage procedure. A prospective comparative study. Complete edentulism cases
Ferrigno et al (2018)
A long-term follow-up study of non-submerged ITI implants in the treatment of totally edentulous jaws. Part I: Ten-year life table analysis of a prospective multicenter study with 1286 implants.
Complete edentulism cases
Helldén et al (2003)
A prospective 5-year multicenter study of the Cresco implantology concept. Complete edentulism cases
Willer et al (2003)
Survival rate of IMZ implants: a prospective 10-year analysis. Complete edentulism cases
Jokstad A, et al (2014)
Immediate function on the day of surgery compared with a delayed implant loading process in the mandible: a randomized clinical trial over 5 years.
Complete edentulism cases
Makkonen et al (1997)
A 5-year prospective clinical study of Astra Tech dental implants supporting fixed bridges or overdentures in the edentulous mandible
Complete edentulism cases
Fischer et al (2012)
Prospective 10‐Year Cohort Study Based on a Randomized Controlled Trial (RCT) on Implant‐Supported Full‐Arch Maxillary Prostheses. Part 1: Sandblasted and Acid‐Etched Implants and Mucosal Tissue
Complete edentulism cases
Cannizzaro et al (2012)
Immediate versus early loading of 6.5 mm-long flapless-placed single implants: a 4-year after loading report of a split-mouth randomised controlled trial
Complete edentulism cases
Brocard et al (2000)
A multicenter report on 1,022 consecutively placed ITI implants: a 7-year longitudinal study Complete edentulism cases
Randow et al (1999)
Immediate functional loading of Brånemark dental implants. An 18-month clinical follow-up study Complete edentulism cases
Rasmusson et al (2005)
A 10-year follow-up study of titanium dioxide-blasted implants Complete edentulism cases
Romeo et al (2004)
Long-term Survival and Success of Oral Implants in the Treatment of Full and Partial Arches: A 7-year Prospective Study with the ITI Dental Implant System
The International Journal of Oral & Maxillofacial Implants 1369h
Appendix Table 1 List of Excluded Articles
Author TitleReason for exclusion
Ostman et al (2012)
Ten years later. Results from a prospective single-centre clinical study on 121 oxidized (TiUnite™) Brånemark implants in 46 patients
Complete edentulism cases
Tözüm et al (2007)
The effect of delayed versus early loading on nitric oxide metabolism around dental implants: an 18-month comparative follow-up study
Complete edentulism cases
Collaert (2011) A 2‐year prospective study on immediate loading with fluoride‐modified implants in the edentulous mandible
Complete edentulism cases
Froberg et al (2006)
Immediate loading of Brånemark System Implants: a comparison between TiUnite and turned implants placed in the anterior mandible.
Complete edentulism cases
Kielbassa et al (2009)
Randomized controlled trial comparing a variable-thread novel tapered and a standard tapered implant: interim one-year results.
Complete edentulism cases
Johansson et al (2008)
Digitally Planned, Immediately Loaded Dental Implants with Prefabricated Prostheses in the Reconstruction of Edentulous Maxillae: A 1-Year Prospective, Multicenter Study
Complete edentulism cases
Naert et al (1999)
A 5-year prospective randomized clinical trial on the influence of splinted and unsplinted oral implants retaining a mandibular overdenture: prosthetic aspects and patient satisfaction
Complete edentulism cases
Melo et al (2009) A prospective follow-up study of 44 mandibular immediately loaded implants using resonance frequency analysis: Preliminary 1-Year results
Complete edentulism cases
Cannizzaro et al (2015)
Immediate loading of fixed cross arch protesies supported by flapless placed super short or long implants : 1 year results from randomized control trial
Complete edentulism cases
Mau et al (2003) Randomized multicenter comparison of 2 IMZ and 4 TPS screw implants supporting bar-retained overdentures in 425 edentulous mandibles
Complete edentulism cases
Jokstad et al (2018)
Comparison of two early loading protocols in full arch reconstructions in the edentulous maxilla using the Cresco prosthetic system: a three-arm parallel group randomized-controlled trial
Complete edentulism cases
Heschl et al (2011)
Immediate rehabilitation of the edentulous mandible with screw type implants: results after up to 10 years of clinical function.
Complete edentulism cases
Becktor et al (2007)
A prospective multicenter study using two different surgical approaches in the mandible with turned Brånemark implants: conventional loading using fixed prostheses.
Complete edentulism cases
Bruggenkate et al (1998)
Short (6-mm) nonsubmerged dental implants: results of a Multicenter clinical trial of 1 to 7 years. Complete edentulism cases
Moheng (2016) Clinical and biologic factors related to oral implant failure: a 2-year follow-up study. Complete edentulism cases
Torroella-Saura et al (2015)
Effect of implant design in immediate loading. A randomized, controlled, split-mouth, prospective clinical trial
Complete edentulism cases
Vercruyssen et al (2014)
Implant- and patient-centred outcomes of guided surgery, a 1-year follow-up: an RCT comparing guided surgery with conventional implant placement
Complete edentulism cases
Morris et al (2000)
Survival and stability (PTVs) of six implant designs from placement to 36 months. Complete edentulism cases
Al-Nawas et al (2012)
A double-blind randomized controlled trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV small-diameter bone level implants in edentulous mandibles--results from a 1-year observation period
Complete edentulism cases
Stellingsma et al (2003)
Satisfaction and psychosocial aspects ofpatients with an extremely resorbedmandible treated with implant-retained overdenture
Complete edentulism cases
Pieri et al (2011) Influence of implant-abutment interface design on bone and soft tissue levels around immediately placed and restored single tooth implants: a randomized controlled clinical trial
Immediate placement
Maló et al (2003) Immediate and Early Function of Brånemark System Implants Placed in the Esthetic Zone: A 1‐Year Prospective Clinical Multicenter Study
Immediate placement
Lindeboom et al (2006)
Immediate loading versus immediate provisionalization of maxillary single-tooth replacements: a prospective randomized study with BioComp implants
Immediate placement
Kielbassa et al (2009)
Randomized controlled trial comparing a variable-thread novel tapered and a standard tapered implant:Interim one-year results.
Immediate placement
Meizi et al (2014) New-design dental implants: a 1-year prospective clinical study of 344 consecutively placed implants comparing immediate loading versus delayed loading and flapless versus full-thickness flap
Immediate placement
Crespi et al (2009)
Radiographic eval-uation of marginal bone levels around platform-switched and non-platform-switched implants used inan immediate loading protocol
Immediate placement
Testori et al (2003)
Immediate non-occlusal loading vs. early loading in partially edentulous patients Immediate placement
Becker et al (2013)
Prospective clinical trial evaluating a new implant system for implant survival, implant stability and radiographic bone changes.
Immediate placement
Bogaerde et al (2010)
Immediate/Early function of Neoss implants placed in maxillas and posterior mandibles: an 18-month prospective case series study.
Immediate placement
Siciliano Vi et al (2009)
Soft tissues healing at immediate transmucosal implants placed into molar extraction sites with buccal self-contained dehiscences. A 12-month controlled clinical trial
Immediate vs. early loading of dental implants: 3-year results of a randomized controlled clinical trial Immediate placement
Zuffetti et al (2016)
A 10-year report from a multicentre randomised controlled trial: immediate non-occlusal versus early loading of dental implants in partially edentulous patients
Immediate placement
Zuffetti et al (2013)
Socket grafting with or without buccal augmentation with anorganic bovine bone at immediate post-extractive implants: 6-month after loading results from a multicenter randomised controlled clinical trial
Immediate placement
Grandi et al (2013)
A 3-year report from a multicentre randomised controlled trial: immediately versus early loaded implants in partially edentulous patients.
Immediate placement
Ormianer et al (2006)
Long-term clinical evaluation of tapered multi-threaded implants: results and influences of potential risk factors.
Immediate placement
Canullo et al (2009)
Double-blind randomized controlled trial study on post-extraction immediately restored implants using the switching platform concept: soft tissue response. Preliminary report
Immediate placement
Testori et al (2001)
A Prospective Multicenter Clinical Study of the Osseotite Implant: Four-Year Interim Report
Immediate placement
Wagenberg et al (1999)
Prospective study of the Langer modification of the Brånemark 5.0-mm implant: 3-year results Immediate placement
Pozzi A et al (2015)
Immediate loading with a novel implant featured by variable-threaded geometry, internal conical connection and platform shifting: three-year results from a prospective cohort study.
Immediate placement
Grandi et al (2015)
Immediate, early (3 weeks) and conventional loading (4 months) of single implants: Preliminary data at 1 year after loading from a pragmatic multicenter randomised controlled triala
Immediate placement
Bogaerde et al (2010)
Immediate/Early function of Neoss implants placed in maxillas and posterior mandibles: an 18-month prospective case series study.
Bone augmentation
Jung et al (2015) Evaluation of a one-piece ceramic implant used for single-tooth replacement and three-unit fixed partial dentures: a prospective cohort clinical trial
Bone augmentation
Chen et al (2007) A prospective clinical study of non-submerged immediate implants: clinical outcomes and esthetic results
Bone augmentation
Buser et al (2002)
Longterm stability of osseointegrated implants in augmented bone: A 5-year prospective study in partially edentulous patients.
Bone augmentation
Orenstein et al (2000)
Variables affecting survival of single-tooth hydroxyapatite-coated implants in anterior maxillae at 3 years
Bone augmentation
Winkler et al (2000)
Implant survival to 36 months as related to length and diameter Bone augmentation
Ioannidis et al (2015)
Titanium-zirconium narrow-diameter versus titanium regular-diameter implants for anterior and premolar single crowns:3-year results of a randomized controlled clinical study
Bone augmentation
Hallman M et al (2001)
A prospective study of treatment of severely resorbed maxillae with narrow nonsubmerged implants: Results after 1 year of loading
Bone augmentation
Esposito et al (2013)
Safety and efficacy of a biomimetic monolayer of permanently bound multi-phosphonic acid molecules on dental implants: 1 year post-loading results from a pilot quadruple-blinded randomised controlled trial
Bone augmentation
Cannizzaro et al (2015)
Early implant loading in the atrophic posterior maxilla: 1-stage lateral versus crestal sinus lift and 8 mm hydroxyapatite-coated implants. A 5-year randomised controlled trial
Bone augmentation
Cannizzaro et al (2009)
Early loading of implants in the atrophic posterior maxilla: lateral sinus lift with autogenous bone and Bio-Oss versus crestal mini sinus lift and 8-mm hydroxyapatite-coated implants. A randomised controlled clinical trial
Bone augmentation
Brocard et al (2000)
A multicenter report on 1,022 consecutively placed ITI implants Bone augmentation
Thoma et al (2014)
Prospective randomized controlled clinical study comparing two dental implant systems: demographic and radiographic results at one year of loading.
Bone augmentation
Luongo et al (2015)
Do repeated changes of abutments have any influence on the stability of peri-implant tissues? Four-month post-loading preliminary results from a multicentre randomised controlled trial
Bone augmentation
Bornstein et al (2008)
Performance of dental implants after staged sinus floor elevation procedures: 5-year results of a prospective study in partially edentulous patients.
Bone augmentation
Canullo et al (2010)
Platform switching and marginal bone-level alterations: The results of a randomized-controlled trial Bone augmentation
Becker et al (2017)
Clinical performance of two‐piece zirconia implants in the posterior mandible and maxilla: a prospective cohort study over 2 years
Bone augmentation
Yu et al (2017) Outcomes of 6.5-mm Hydrophilic Implants and Long Implants Placed with Lateral Sinus Floor Elevation in the Atrophic Posterior Maxilla: A Prospective, Randomized Controlled Clinical Comparison
Bone augmentation
Corrente et al (2009)
Short porous implants in the posterior maxilla: a 3-year report of a prospective study. Bone augmentation
The International Journal of Oral & Maxillofacial Implants 1369j
Appendix Table 1 List of Excluded Articles
Author TitleReason for exclusion
Naert et al (2002)
Biologic outcome of implants supported restirstions in the treatment of partial edentualism Bone augmentation
Angelis et al (2014)
Platform switching versus conventional technique: a randomized controlled clinical trial Involved anterior implants
Cannizzaro et al (2008)
Immediate functional loading of implants placed with flapless surgery versus conventional implants in partially edentulous patients: a 3-year randomized controlled clinical trial
Involved anterior implants
Merli et al (2012) Immediate versus early non-occlusal loading of dental implants placed flapless in partially edentulous patients: a 3-year randomized clinical trial
Involved anterior implants
Ostman et al (2007)
Direct loading of Nobel Direct and Nobel Perfect one-piece implants: a 1-year prospective clinical and radiographic study
Involved anterior implants
Mayer et al (2002)
The single-tooth implant: A viable alternative for single-tooth replacement Involved anterior implants
Turkyilmaz I et al (2007)
A 4-year prospective clinical and radiological study of maxillary dental implants supporting single-tooth crowns using early and delayed loading protocols.
Involved anterior implants
Karlsson et al (1997)
Single-tooth replacement by osseointegrated Astra Tech dental implants: a 2-year report Involved anterior implants
Karlsson et al (1998)
A 2-year report on maxillary and mandibular fixed partial dentures supported by Astra Tech dental implants. A comparison of 2 implants with different surface textures
Involved anterior implants
Benic et al (2013)
Titanium-zirconium narrow-diameter versus titanium regular-diameter implants for anterior and premolar single crowns: 1-year results of a randomized controlled clinical study
Involved anterior implants
Khayat et al (2007)
Prospective clinical evaluation of 835 multithreaded tapered screw-vent implants: results after two years of functional loading.
Involved anterior implants
Mericske-Stern et al (2001)
Clinical evaluation and prosthetic complications of single tooth replacements by non-submerged implants
Involved anterior implants
Henry et al .2003 Prospective multicenter study on immediate rehabilitation of edentulous lower jaws according to the Brånemark Novum protocol.
Involved anterior implants
Heinemann et al (2016)
Immediate occluding definitive partial fixed prosthesis versus non-occluding provisional restorations- 4-month post-loading results from a pragmatic multicenter randomised controlled trial
Involved anterior implants
Irinakis T et al (2009)
Clinical evaluation of the NobelActive implant system: a case series of 107 consecutively placed implants and a review of the implant features.
Involved anterior implants
Testori et al (2007)
Immediate nonocclusal versus early loading of dental implants in partially edentulous patients: 1-year results from a multicenter, randomized controlled clinical trial
Involved anterior implants
Esposito et al, (2016)
Dental implants with internal versus external connections: 5-year post-loading results from a pragmatic multicenter randomised controllod trial
Involved anterior implants
Cooper et al (2007)
Three-year evaluation of single-tooth implants restored 3 weeks after 1-stage surgery. Involved anterior implants
Hahn et al (2011) Four-year treatment and radiographic outcomes of 1-piece implants used in immediate function: a prospective study in a single private practice.
Involved anterior implants
Eghbali et al (2012)
Single implant treatment in healing versus healed sites of the anterior maxilla: a clinical and radiographic evaluation.
Involved anterior implants
Schropp et al (2008)
Clinical outcome and patient satisfaction following full-flap elevation for early and delayed placement of single-tooth implants: a 5-year randomized study.
Involved anterior implants
De Rouck (2008) Immediate single-tooth implants in the anterior maxilla: a 1-year case cohort study on hard and soft tissue response.
Involved anterior implants
Winker et al (2000)
Implant survival to 36 months as related to length and diameter. anterior endentulous
Astrand et al (2004)
A three-year follow-up report of a comparative study of ITI Dental Implants and Brånemark System implants in the treatment of the partially edentulous maxilla.
Involved anterior implants
Zembic A et al (2009)
Randomized-controlled clinical trial of customized zirconia and titanium implant abutments for single-tooth implants in canine and posterior regions: 3-year results.
Prospective multicenter clinical trial of 3i machined-surface implants: results after 6 years of follow-up.
Involved anterior implants
Jones et al (1999)
A 5-year comparison of hydroxyapatite-coated titanium plasma-sprayed and titanium plasma-sprayed cylinder dental implants.
Involved anterior implants
Deporte et al (1998)
Use of the Endopore dental implant to restore single teeth in the maxilla: protocol and early results. Involved anterior implants
Cochran et al (2011)
A 5-year prospective multicenter study of early loaded titanium implants with a sandblasted and acid-etched surface.
Involved anterior implants
Barone et al (2012)
A randomized clinical trial to evaluate and compare implants placed in augmented versus non-augmented extraction sockets: 3-year results.
Involved anterior implants
Lindeboom et al (2006)
Immediate loading versus immediate provisionalization of maxillary single-tooth replacements: a prospective randomized study with BioComp implants.
Involved anterior implants
Felice et al (2014)
A comparison of two dental implant systems in partially edentolous patients: 1-year post loading results from a pragmatic multicentre randomised
Involved anterior implants
Dahlin et al (2013)
One-year results of a clinical and radiological prospective multicenter study on NEOSS® dental implants.
Involved anterior implants
Ana Carrillo de Albornoz et al (2014)
A randomized trial on the aesthetic outcomes of implant supported restorations with zirconia or titanium abutments
Involved anterior implants
Bogaerde et al (2004)
Early function of splinted implants in maxillas and posterior mandibles, using Brånemark System Tiunite implants: an 18-month prospective clinical multicenter study.
Machined implants
Polizzi et al (2000)
Immediate and delayed implant placement into extraction sockets: a 5-year report. Machined implants
Schincaglia et al (2007)
Immediate loading of dental implants supporting fixed partial dentures in the posterior mandible: a randomized controlled split-mouth study--machined versus titanium oxide implant surface.
Machined implants
Henry et al (1995)
Osseointegrated implants for single tooth replacement in general practice: a 1-year report from a multicentre prospective study.
The International Journal of Oral & Maxillofacial Implants 1369l
Appendix Table 2 Bias Risk Assessment for the Included RCTS Using the Cochrane Risk of Bias Tool for Randomized Controlled Trials (Higgins et al, 2011)
Study
Random sequence generation
Allocation concealment
Blinding of participants
and personnel
Blinding of outcome
assessment
Incomplete outcome
data addresses
Selective reporting
Other bias
Overall risk of bias
Bolle et al 2018 Low Low High Low Low Low Low Moderate
Hadzik et al 2018 High High High Unclear Low Low Unclear High
Ayna et al 2018 High High High Unclear Low Unclear Low High
Bernardi et al 2018 High High High High Low Unclear Low High
Guarnieri et al 2018 Low Low Low Unclear Low Low Low Moderate
Gastaldi et al 2018 Low Low Unclear Low Low Low Low Moderate
Naenni et al 2018 Low Low High Low Low Low Low Moderate
Felice et al 2018 Low Low High High Low Low Unclear High
Taschieri et al 2018 Low Low Low Unclear Low Low Unclear High
Zadeh et al 2018 Low Low Unclear Low Low Low Low Moderate
Waechter et al 2017 Low Low Low Low Low Low Low Moderate
Pohl et al 2017 Low Low High Unclear Low Low Low High
Bechara et al 2017 Low Low High Unclear Low Low Low Moderate
Gastaldi et al 2017 Low Low Unclear Low Low Low Low Moderate
Tallarico et al 2017 Low Low Low Low Low Low Low Low
Bömicke et al 2017 Low Low Low Low Low Low Low Low
Akoglan et al 2017 High High High Unclear Low Low Unclear High
Felice et al 2016 Low Low Low High Low Low Low Moderate
Rossi et al 2016 Low Low High Low Low Low Low Moderate
Al-Hashedi et al 2016
Low Unclear Low Low Low Low Low Moderate
Nedir et al 2016 Unclear Unclear Unclear Unclear Low Low Unclear High
Clelland et al 2016 Unclear Unclear Unclear Low Low Low Low High
Esposito et al 2014 Low Unclear Low Low Low Low Low Moderate
Romeo et al 2014 Low Low High Low Low Low Low Moderate
Cannullo et al 2014 Low Low Low Low Low Low Low Low
Pozzi et al 2014 Low Low Low Low Low Low Low Low
Kim et al 2013 Unclear Unclear Unclear Unclear Low Low Low High
Telleman et al 2013 Low Low Low Low Low Low Low Low
Telleman et al 2012 Low Low Low Low Low Low Low Low
Canullo et al 2012 Low Low Low Unclear Low Low Low Moderate
Meloni et al 2012 Low Low Low Low Low Low Low Low
Barewal et al 2012 Low Low Low Unclear Low Low Low Moderate
Appendix Table 3 Quality Assessment of the Included Cohort Studies Using Newcastle-Ottawa Scale
Study Selection Comparability Outcome/exposure
Hadzik et al (2018) ★★ ★ ★★★Shilpa et al (2018) ★★ ★ ★Malchiodi et al (2018) ★★ ★ ★★Han et al (2018) ★★★ ★★ ★★★Benlidayi et al (2018) ★★ ★ ★Adanez et al (2018) ★★ ★ ★★Rossi et al (2017) ★★ ★★ ★★★Villarinho et al (2017) ★★★ ★★ ★★★Lee et al (2016) ★★ ★ ★★★Ghariani et al (2016) ★ ★ ★Malmstrom et al (2016) ★★ ★ ★★★Mangano et al (2016) ★★ ★ ★★★★Moergel et al (2015) ★★ ★ ★★Markovic et al (2015) ★★ ★ ★Rossi et al (2015) ★★★ ★★ ★★★Bratu et al (2014) ★★ ★ ★★★Mangano et al (2013) ★★★ ★★ ★★★★Kennedy et al (2013) ★★★ ★ ★★★Pieri et al (2012) ★★ ★ ★★★Canullo et al (2012) ★★★★ ★ ★★★★Enkling et al (2011) ★★ ★ ★★★Alghamdi et al (2011) ★★ ★ ★★Payer et al (2010) ★★ ★★ ★★★MacDonald et al (2009) ★★★★ ★ ★★Vigolo et al (2009) ★★★★ ★★ ★★★Achilli et al (2007) ★★ ★ ★★Roccuzzo et al (2002) ★★★ ★★ ★★★★Palmer et al (2000) ★★★ ★★ ★★★
Appendix Table 4 Characteristics of Included Articles
Reference No. (#) First Author (year of publication) Type and Design
Population characteristics
1. No. of patients total2. Mean Age 3. Range of Age
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#2Adanez et al 2018Prospective Split Mouth
1. 102. N/A3. N/A
1. Y2. Y3. N4. Y
1. 402. Mand3. Dentium §‡Ø
45. 7mm (20) – 10mm (15) 12mm (5)6. 4 mm7. BL8. 2
1. Internal2. Screw3. Splinted4. Late
1. 122. 03. 0
#3Bolle et al (2018)RCT
1. 402. 59–603. 25–77
1. Y2. Y3. N4. Y
1. 802. Max/Mand3. Twinkon Universal SA2 ‡†4. Sand-blasted acid-etched5. 4 mm (80)6. 4 mm - 4.5 mm7. STL8. 2
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#8Guarnieri et al (2018)RCT
1. 282. 513. 21–82
1. N/R2. Y3. Y4. Y
1. 642. Max/Mand3. Tapered internal Laser-Lok ‡‡4. Laser micro-grooved ‡‡5. 6 mm (14) - 7.5 mm (14) - 9 mm (18) - 10.5 mm (10) - 12 mm (8)6. 4.6 mm7. BL8. 2
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#14Taschieri et al (2018)RCT
1. 272. 523. 31–77
1. Y2. Y3. N4. N/R
1. 422. Max3. Interna Universal /Universal plus Platform §††4. Sand blasted (+ Liquid P-PRP)5. 6.5 mm (14) - 7.5 mm (16) - 8.5 mm (12)6. 3.75 mm - 4 mm - 4.5 mm7. BL8. 2
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#20Villarinho et al (2017)Prospective cohort
1. 202. 523. 25–76
1. Y2. N/R3. Y4. Y
1. 462. Max/Man3. Straumann, Standard Plus ‡4. Sand blasted large grit and acid etched (SLActive).5. 6mm (46)6. 4.17. STL8. 1
1. External2. Screw/cemented3. Splinted/Non-splinted4. Late
1. 362. 03. 0
#22Tallarico et al (2017)RCT
1. 122. 56.23. 42–67
1. Y2. N3. N4. N/R
1. 122. Max/Mand3. Ultra-Wide §‡4. Alumina sand blasted, and acid etched5. 8.5 mm (1) - 10 mm (9) - 11.5 mm (2)6. 7 mm5. BL8. 2
1. Internal2. Screw3. Non-splinted4. Late
1. 122. 03. 0
#23Bömicke et al (2017)RCT
1. 352. 52.93. N/R
1. N/R2. N3. N4. Y
1. 352. Mand3. Nobel Biocare, NobelDirect Groovy and NobelReplace Tapered Groovy ‡Ø4. Anodically oxidized rough surface.5. 10 mm (35)6. 4.3mm - 5 mm7. BL8. 1 and 2
1. Internal2. Cemented3. Non-splinted4. Immediate or late
1. 362. 03. 1
#24Akoglan et al (2017)RCT
1. 392. 41.33. N/R
1. N/R2. Y3. Y4.N/R
1. 392. Max3. DentiumSuperline §‡Ø4. Sand blasted large grit and acid etched5. 10 mm (5) - 12 mm (24) - 14 mm (10)6. 3.8 mm - 4.3 mm - 4.8 mm7. BL8. N/R
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#26Ghariani et al (2016)Prospective cohort
1. 122. N/R3. N/R
1. N/R2. N/R3. N/R4. N/R
1. 122. Mand3. Integra-CP™ §†4. Hydroxylapatite treated5. 5 mm (1) - 6 mm (6) - 8 mm (5)6. 4.17. BL8. 2
1. Internal2. Cement3. Non-splinted4. Late
1. 62. 03. 0
#27Malmstrom et al (2016)Prospective cohort
1. 302. 53.6 (12.8)3. 22–80
1. Y2. N3. N/R4. Y
1. 802. Max/Mand3. Astra, OsseoSpeed †4. Fluoride-modified surface.5. 6 mm (25) - 8 mm (20) - 11 mm (35)6. 4 mm7. BL8. 1 and 2
1. Internal2. Cement3. Splinted, Non-splinted4. Early and Late
1. 242. 1 (6mm)3. 0
#28Felice et al (2016)RCT
1. 752. 533. 20–76
1. Y2. Y3. N4. Y
1. 1102. Max/Mand3. TwinKon ‡†4. Sand-blasted acid-etched5. 4 mm (110)6. 4 mm7. BL8. 1 or 2
1. External2. Screw3. Splinted/Non-splinted4. Late
1. 122. 23. 0
#29Rossi et al (2016)RCT
1. 452. 483. 30–74
1. Y2. Y3. N/R4. Y
1. 302. Max/Mand3.Staraumann, Standard Plus, SLA ‡4. Sand blasted large grit and acid etched (SLActive).5. 6 mm (30) - 10 mm (30)6. 4.1 mm7. STL8. 1
1. Internal2. N/R3. Non-splinted4. Early
1. 602. 1 (6 mm)3. 3 (6 mm) - 1 (10 mm)
#30Mangano et al (2016)Prospective
1. 512. 59.83. 40–75
1. Y2. Y3. Y4. Y
1. 682. Max/Mand3. Leone Ø4. Blasted (Al3O2) and Acid-etched (HNO3)5. 6.5 mm (68)6. 57. BL8. 2
1. Internal2. Cement3. Splinted/Non-Splinted4. Late
1. 602. 03. 2
#31Al-Hashedi et al (2016)RCT
1. 202. 47.13. 25-70
1. N/R2. N3. N4. Y
1. 402. Mand3. Bicon §† and Ankylos †§4. Integra-Ti surface and Friadent5. 6 mm (2) - 8mm (38)6. 3.5mm - 4.5 mm7. BL8. 2
1. Internal2.Cemented3. Non-splinted4. Late
1. 122. 03. 0
Max = maxilla; mand = mandible.‡Straumann AG (Basel, Switzerland); †Astra Tech (Dentsply, Sirona Implants); ††Zimmer Biomet; †††MegaGen Implant; ‡‡Biohorizons; ‡†Twinkon Global D; ‡††Equinox Medical Technologies B.V. de Stuwdam; †‡†Winsix, BioSAFin; ††‡ Hi-Tec Implant; §‡Osstem; §†Bicon Dental Implants; †§ Friadent; ‡§Implants; §††Signo Vinces Europa; §‡‡Centurion; ØNu- cleoss Implants; ‡Ø Nobel Biocare); ؆CAMLOG Biotechnologies; §‡Ø Dentium; §§§Sweden & Martina; §‡§MIS Implants; ‡§§Innova, Sybron Dental.
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#43Kim et al (2013)RCT
1. 502. 503. N/R
1. N/R2. N/R3. N4. N/R
1. 1002. Max/Mand3. Osstem TSIII §‡ or Zimmer TSV implants ††4. TSIII: Resorbable blasted media (RBM) treatment with hydroxyapatite (HA) particles in the upper part and HA coating in the midbody area.5. 10 mm (100)6. 4.5 mm - 4.7 mm - 5.0 mm7. BL TSV: Microtextured (RBA) + HA coating in the mid portion with a machined collar.8. 1
1. Internal2.N/R3. Splinted4. Immediate
1. 122. 03. 0
#44Mangano et al (2014)Prospective cohort
1. 1942. 493. 24–74
1. Y2. Y3. Y4. Y
1. 2152. Max/Mand3. Leone Ø4. Blasted (Al3O2) particles and acid- etched (HNO3)5. 8 mm (215)6. 3.3 mm - 4.1 mm - 4.8 mm7. BL8. 2
1. Internal2. Cemented3. Non-splinted4. Late
1. 1202. 23. 1
#45Telleman et al (2013)RCT
1. 912. 503. 18–70
1. N/R2. N3. N/R4. Y
1. 1492. Max/ Mand3. Certain, Prevail; ††4. Dual-acid surface and a discrete crystalline deposition of nanometer-sized CaP particles5. 8.5 mm (149)6. 4.1 mm - 5 mm7. BL8. 1
1. Internal2. Cemented3. N/R4. Late
1. 122. 63. 3
#46Kennedy et al (2013)Prospective cohort
1. 182. 62.43. 49–76
1. N/R2. N3. N/R4. Y
1. 822. Max/Mand3. Astra, Osseospeed †4. Fluoride-modified surface.5. 6mm (38) - 8 mm (10) - 9 mm (22) - 11 mm (12)6. 3.5 mm - 4 mm - 5 mm7. BL8. 2
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#48Canullo et al (2012)RCT
1. 122. 58.23. N/R
1. N/R2. Y3. N/R4. N/R
1. 82. Max3. Global Implants §§§4. Sand-blasted and acid-etched surface5. 13 mm (8)6. 4.3 mm - 4.8 mm7. BL8. 2
1. Internal2. Cemented3. Splinted4. Late
1. 182. 03. 0
#49Telleman et al (2012)RCT
1. 752. 55.353. 23–75
1. N/R2. N3. N/R4. Y
1. 1132. Max/Mand3. Certain, Prevail ††4. Dual-acid etched surface5. 8.5 mm (113)6. 4.1 mm - 5 mm7. BL8. 1
1. Internal2. Cemented3. Splinted/Non-splinted4. Late
1. 602. 63. 1
#50Meloni et al (2012)RCT
1. 202. 463. 28–70
1. Y2. Y3. N4. Y
1. 402. Mand3. Nobel Biocare, Nobel Replace Tapered Groovy ‡Ø4. Anodically oxidized rough surface.5. 8 mm (4) - 10 mm (36)6. 4.3 mm - 5.0 mm7. BL8. 1 and 2
1. Internal2. Cemented3. Non-splinted4. Immediate and late
1. 122. 03. 0
#51Barewal et al (2012)RCT
1. 252. N/R3. 20–82
1. Y2. N3. N4. Y
1. 262. Max/Mand3. Astra, Osseospeed †4. Fluoride-modified surface.5. 11 mm (13) - 13 mm (13)6. 4 mm7. BL8. 1
1. Internal2. Cement3. Non-splinted4. Immediate or early
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
1. External2. Screw3. Splinted/Non-splinted4. Late
1. 122. 13. 0
#55Payer et al (2010)Prospective cohort
1. 242. 45.83. 29–63
1. N/R2. N3. N4. Y
1. 402. Mand3. XiVE †4. Large grit-blasting, high temperature acid etching.5. 11 mm (7) - 13 mm (14) - 15 mm (19)6. 3.4 mm - 3.8 mm - 4.5 mm - 5.5 mm7. BL8. 1
1. 712. Mand3. Osstem SSII §‡ and Straumann Standard Plus SLA ‡4. Osstem: Resorbable media blast (RBM) Straumann: Sand blasted large grit and acid etched5. 10 mm (75)6. 4.1 mm7. STL8. 1
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#59Roccuzzo et al (2008)RCT
1. 322. N/R3. 26–59
1. N/R2. Y3. N4. Y
1. 1362. Max/Mand3. Straumann, Standard Plus SLA and TPS ‡4. Standard Plus: Sand blasted large grit and acid etched; TPS: Titanium plasma sprayed5. 8 mm (16) - 10 mm (80) - 12 mm (40)6. 4.1 mm - 4.8 mm7. STL8. 2
1. Internal2. Cemented3. Splinted/Non-splinted4. Early/ Late
1. 602. 03. 0
#60Schincaglia et al (2008)RCT
1. 302. 50.533. 35–68
1. Y2. Y3. N/R4. N/R
1. 302. Mand3. Nobel Biocare, TiUnite ‡Ø4. Anodically oxidized rough surface.5. 8.5 mm (8) - 10 mm (9) - 11.5 mm (13)6. 5 mm7. BL8. 1
1. Internal2. Screw/Cemented3. Non-splinted4. Immediate or late
1. 162. 03. 1 (10 mm)
#61Achilli et al (2007)Prospective cohort
1. 512. 52.53. 31–80
1. Y2. Y3. N4. Y
1. 1202. Max/Mand3. Replace Select Tapered ‡Ø4. Anodically oxidized rough surface, TiUite.5. 10 mm (71) - 13 mm (47) - 16 mm (2)6. 3.5 mm - 4.3 mm - 5 mm - 6 mm7. BL8. 1
1. Internal2. Cemented3. Splinted4. Immediate/ early
1. Total of included implants 2. Location (max;mand) 3. System 4. Surface treatment5. Length (n of implants) 6. Diameter 7. Bone or tissue level 8. Stages
Prosthetic characteristics
1. Abutment connection2. Type of retention 3. Splinted/non-splinted 4. Timing of restoration
Follow-up
1. Follow-up (mo) 2. Early failures 3. Delayed failures
#64Rocci et al (2003)RCT
1. 442. 513. 20–69
1. N/R2. Y3. N/R4. N/R
1. 1212. Mand3. Brånemark System® ‡Ø4. Anodically oxidized rough surface, TiUnite.5. 7mm (6) ; 8.5 mm (4) ; 10 mm (11) ; 11.5 mm (6); 15 mm (10) ; 18 mm (7)6. N/R7. BL8. 1
1. Internal2. Cemented3. Splinted4. Immediate
1. 122. 03. 1(10 mm) ; 2 (18 mm)
#65Roccuzzo et al (2002)
1. 192. N/R3. 35–65
1. N/R2. N3. N/R4. Y
1. 362. Max3. Straumann, Standard Plus ‡4. Sand- blasted, large and acid etched (SLA).5. 8 mm (9) - 10 mm (22) - 12 mm (5)6. 4.1 mm - 4.8 mm7. STL8. 1
1. Internal2. Cemented3. Splinted/Non-splinted4. Early