Tissue Augmentation 2012

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494 Posters – Tissue Augmentation andEngineering

The use of Platelets rich fibrin (PRF) inreconstructive dental implant treatment

Ahmed AyoubEgyptian Society of Oral Implantology, Alexandria, Egypt

Background: When minimal bone width is present, implant

placement becomes a challenge and often resulting in reces-

sion and dehiscence around the implant that leads to subse-

quent gingival recession. To correct such defect, soft tissue

autografting and allografting to correct a buccal dehiscence

around a malpositioned implant placed by a different surgeon

is used. Platelet-rich fibrin (PRF) belongs to a new generation

of platelet concentrates, with simplified processing and with-

out biochemical blood handling, it is a strictly autologous

fibrin matrix containing a large quantity of platelet and leuko-

cyte cytokines. The use of platelet gel to improve soft and

hard tissue regeneration is a recent technique in implantology.

So in this case the PRF is used to the dehiscence.

Aim: The aim is to cover the exposed implant threads using

PRF instead of using bone grafts and connective tissue grafts.

Methods: A healthy 24-year-old woman presented with chief

complaint of “my implant is showing through my gingival tis-

sue”. Patient was wondering if there is any periodontal treat-

ment available to mask the showing of implant threads

through the gingival tissue and prevent further recession.

With excellent oral hygiene, upon clinical examination, there

was minimal buccal gingival thickness around the implant inupper central incisor. Her recent dental history included

extraction of permanent tooth #24, and an immediate implant

was placed in site #24. Her previous dental treatment was ren-

dered by a different surgeon. The patient presented to Dental

smile center 4 months after implant placement. The implant

appeared to be osseointegrated with a buccal dehiscence and

10 – 20% of facial implant showing through gingival tissue due

to minimal bone width. Since the implant was osseointe-

grated, removal of implant was not considered fearing damage

to adjacent teeth when trephining the implant. Also, due to

loss of buccal bone cortex, The positioning of implant outside

the bony envelope and possible sloughing of fragile buccal

Gingival tissue-guided bone regeneration were not recom-

mended. Faced with the esthetic concerns and possible future

recession around that implant, soft tissue gingival grafting

was recommended to augment the keratinized gingiva and

improve esthetics.

Results: From a radiologic and histologic point of view at

4 months after surgery, the use of PRF as the sole filling or

covering material stabilized a high volume of natural regener-

ated bone and soft tissue over the exposed implant threads.

Choukroun’s PRF is a simple and inexpensive biomaterial,

and its systematic use during covering bony defect above

implant seems a relevant option.

Conclusions and clinical implications: The use of PRF mem-

brane could cover the exposed implant threads instead of

using traditional bone grafts and connective tissue grafts.


Implants in a patient with bilateral cleft lip andpalate

Davor Brajdic, Darko Macan, Domagoj Zabarovic,Josip BiocicSchool of Dental Medicine, Universitiy Hospital Dubrava,

Zagreb, Croatia

Background: Dentoalveolar rehabilitation in patients with cleft

lip and palate represents a clinical challange. Conventionaltreatment options including fixed prosthesis and/or assistant

orthodontic treatment are nowadays increasingly replaced by

endosseous implants. Besides the most frequently lacking

or malformed lateral incisors there is often not enough bone

volume after primary bone grafting.

Aim: Secondary bone grafting prior to dental implant place-

ment in a patient with a bilateral cleft lip and palate.

Methods: We present a case of a 28-year-old male patient with

a bilateral cleft lip and palate who rejected the conventional

rehabilitation with fixed partial prosthesis and insisted on

placement of two dental implants. The treatment was preceed-

ed by augmentation of alveolar bone. Prior to treatment CBCTwas performed and showed only narrow alveolar bone bridges

at the cleft positions. At the upper right lateral incisor posi-

tion bone bridge was more palatal, at the left position more

vestibular. Only one mandibular ramus block was harvested,

splitted and mixed with particulate xenograft (Bio-Oss®,

Geistlich, Germany) as an onlay vestibular graft at the right

position and as onlay palatal graft at the left. Resorbable mem-

brane (Bio-Gide ®, Geristlich, Germany) was used. Six months

later two dental implants (Ankylos ®, Dentsply Friadent,

Germany) were placed at augmented places that after three

more months were loaded with metal cheramic crowns. Bone

and soft tissue volume were satisfactory.

Results: After a 2-year follow-up a satisfactory esthetic and

functional result could be observed.

Conclusions and clinical implications: These patients require

secondary bone grafting not only to achieve sufficient osseous

support for functionally loaded implants, but also to achieve

an appropriate alveolar bone volume for a satisfactory esthetic

result. Moreover, functional stimulation of the implant limits

resorption of the grafted bone.

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Mineralized human allograft for the preservationof post-extraction socket

Marco Clementini,1 Gianluca Furlani,1 GiuliaDobrenji,1 Corrado Agrestini,1 Davide Zaffe,2

Alberto Barlattani1

1University Tor Vergata, Rome, Italy, 2University of Modena and

Reggio Emilia, Modena, Italy

Background: Reduction of alveolar height and width after

tooth extraction could be unfavourable for future implant

placement, especially in the anterior maxilla where bone vol-

ume is significant for biologic and esthetic reasons. During

the last years various biomaterials and surgical techniques

have been described to maintain dimensions of the residual

alveolar ridge, thus allowing a tridimensional correct implant

placement for a final esthetic implant supported restoration.

Aim: The objective of the present investigation was to evalu-

ate the efficacy of a surgical technique using mineralizedhuman allograft on counteracting dimensional changes of the

alveolar socket after tooth extraction.

Methods: In 10 patients, 10 single extraction sites in the ante-

rior area were grafted by means of mineralized human allo-

graft and was covered by a collagen membrane in all cases.

Intraoral radiographs and clinical measurement were taken at

baseline and after 4 months. At that time a reentry surgery

was performed and prior to implant placement a biopsy core

was obtained and preserved in formalin to calculate fractions

of bone mineral, connective tissue and residual graft material.

Results: After 4 months of healing the intraoral radiographs

showed a mean differcence of bone level heigth of 0.78(SD ± 0.79) mm., while clinical measurements showed a mean

reduction of 1.2 (SD ± 0.9) mm. in width, allowing to accept

normal diameter implants. The specimens harvested showed a

mean of 31.9% of mineralized bone, 54.2% of connective tis-

sue, and 13.93% of residual graft.

Conclusions and clinical implications: The results of this study

show that although some degree of bone modelling and

remodelling will occur after tooth extraction, a surgical tech-

nique using mineralized human allograft resulted in signifi-

cantly less vertical and horizontal contraction of the alveolar

bone crest, suggesting that it may be useful for alveolar ridge

preservation prior to dental implant placement, especially in

the esthetic region.


Titanium micromesh

Giulio ContiFondazione IRCCS Cà Granda Fondazione policlinico, Milano,

Italy

Background: Different techniques for atrophic alveolar bone

ridges reconstruction are described in literature, such as

resorbable and non-resorbable membranes and titanium

micromeshes. During the last years titanium meshes, in

association with autologous and heterologous bone, have been

used and tested in oral surgery for partial or total alveolar

ridges augmentation.

Aim: Aim of this work was to present cases describing the

use of titanium micromesh combined with autologous and

heterologous bone grafts in patients affected by alveolar bone

resorption.

Methods: Before surgery, a radiologic investigation based on

panoramic radiography and computed tomography (CT DEN-

TALSCAN) was performed. During surgery, after opening a

full thickness flap, a titanium mesh was prepared according to

the effective size of the bone defect (misured with a periodon-

tal probe). The mesh was fixed to the bone using titanium

mini-screws and/or pins. Before mesh positioning, heterolo-

gous (Geistlich Bio-Oss) and autologous bone chips were

applied under the grid to fill the bone defect. Before closing

the flap and suturing, a resorbable membrane (Geistlich Bio-

Gide) was used to cover the mesh. Approximately 5 months

after first surgery, the mesh was removed, and at the same

time dental implants (GLOBAL, Sweden and Martina, Italy)

were postioned in order to reduce postoperative discomfortand avoid a third surgery.

Results: In all the cases, a good increase of the alveolar bone

ridge to insert implant fixtures with good primary stability

and without necessity for further regeneration was obtained.

In one of the cases, an early exposure of the mesh was

observed after 2 weeks. However, this event didn’t compro-

mised the outcome of the procedure.

Conclusions and clinical implications: Titanium mesh is a reli-

able containment system used for reconstruction of the max-

illa and the mandible. This material tolerates exposure very

well and gives predictable results.

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A novel cellulose – hydroxyapatite scaffold forbone tissue regeneration

Povilas Daugela,1 Gintaras Juodzbalys,1

Jolanta Liesiene,2 Odeta Petrauskaite,2 Pedro Gomes,3

Elisabete Costa4

1Lithuanian University of Health Sciences, Kaunas, Lithuania,2Kaunas University of Technology, Kaunas, Lithuania,3University of Porto, Porto, Portugal, 4CICECO, University of

Aveiro, Aveiro, Portugal

Background: Nowadays much attention is focused on polymer-

ceramic three-dimensional scaffolds for bone tissue regenera-

tion in defect site. For a successful performance the ideal

scaffold should be a 3D interconnected porous structure able to

promote cell adhesion, proliferation and vascularisation, while

enabling a controlled supply of bioactive substances that might

influence the behaviour of incorporated or ingrown cells.

Aim: To investigate a novel cellulose-based porous compos-ites with hydroxyapatite for the bone scaffold.

Methods: The composites were fabricated by saponification of

diacetylcellulose adding hydroxyapatite. After the reaction the

obtained gel of regenerated cellulose was homogeneously

immobilized with hydroxyapatite. In order to create suitable

matrix the composites were freeze-dried.

Results: It was found out that the conditions of lyophilisation

highly influenced the morphology of the matrix. The porosity

of the scaffolds was up to 75% with pores of different sizes up

to 770 lm. The results of bioactivity test in vitro showed that

bone-like apatite appeared onto the surface after 7 days of

immersion in simulated body fluid. Furthermore, the behav-iour of MG-63 human osteoblastic-cells on investigated cellu-

lose matrix was examined. It was found that the scaffolds are

not cytotoxic and induce the growth of the cells.

Conclusions and clinical implications: From the obtained results

it could be concluded that prepared scaffolds have a great

potential for bone tissue ingrowth in vivo. Attained results

substantiate the suitable application of cellulose/hydroxyapa-

tite scaffolds in bone tissue engineering applications.


Homogenous bone block for the reconstructionof severely resorbed maxilla

Bruno Fusaro1,2

1Professor Coordinator of the Postgraduate Program in Implant

DentEstá cio de Sá University, Juiz De Fora, Brazil, 2Master’s

degree in Implantology by University of Sagrado Coração, Bauru,

Brazil

Background: Pre-implant augmentative surgery is a prerequi-

site in many cases in the severly resorbed maxilla to achieve a

stable, long-term esthetic final result. Homogenous grafts are

among of the most used techniques for bone reconstruction.

Aim: The aim of the present study was evaluate by CT scans

the bone improvement after grafting with freeze block bone

homogenous in severely resorbed maxilla, including horizontal

gain in the region of canine fossa and vertical gain in maxil-

lary sinus.

Methods: Six patients (3 male, 3 female) aged between 38 and

65 years-old underwent 18 bone homogenous blocks in 12sinus elevation and 12 canine fossa regions augmentation. The

elevation of the maxillary sinus floor was made by particulate

block. After 8 months CT mensurements were taken at the

canine fossa region, based on the distal surface of the nasal

cavity and on sinus region. Two examiners used specific soft-

ware on the images obtained by CT to measure the bone

improvement. Implants were placed 8 months after the first

surgery.

Results: Minor complications such as wound dehiscence and

bone blocks superficial necrosis were observed however the

results showed an average gain of 5.9 mm on fossa canine

regions and 8.4 mm on the maxillary sinus region.Conclusions and clinical implications: It was concluded that

there was a considerable bone gain and good implant primary

stability so homogenous bone block appear to hold promise

for grafting the atrophic maxilla.


Adsorbed Periostin protein on titanium surfacesaffects osteoblastic cell behavior

Carlo Galli, Simone Lumetti, Marilina Piemontese,

Giovanni Passeri, Guido MacalusoUniversity of Parma, Parma, Italy

Background: In tissue engineering, stimulating the cells to dif-

ferentiate into the right phenotype to regenerate the tissue

lost requires an environment providing the same factors that

govern cellular processes in vivo. A biomimetic approach to

tissue engineering requires to direct the assembly of normal

tissues using biologically mimicking the signals present in the

extracellular matrix (ECM). Periostin is a matricellular protein

highly expressed in periodontal ligament and periostium and

it is up-regulated during tissue remodeling and wound repair.

Periostin has been shown to be required for the stability,

maintenance and mechanotransduction in bone. We have

therefore hypothesized that Periostin can be used to coat

implant surfaces, to promote osteoblast differentiation and

therefore surface integration in the tissue.

Aim: The goal of the present study was to investigate whether

Periostin coating could improve the response of osteoblastic

cells to implant surfaces with different topography.

Methods: Polished or sand-blasted/acid-etched (SLA) commer-

cially pure titanium surfaces were incubated with a 20 mg/ml

solution of recombinant Periostin and the murine osteoblastic

cell line MC3T3 was cultured on coated or uncoated discs in

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complete DMEM with 10% Fetal Bovine Serum. Cell adhesion

was measured with a ATP-based bioluminescent assay (Cell-

Titer Glo; Promega) and the expression of osteoblastic func-

tion-related genes was quantified by Real Time PCR.

Results: Periostin increased cell adhesion on Polished surfaces

at 4 h and increased the expression of Alkaline Phosphatase,

Osteoprotegerin and Connective Tissue Growth Factor on

smooth surfaces, although it did not affect them on SLA sam-

ples. Levels of mRNA for Collagen1a1, the main structuralcomponent of extracellular matrix, and Osteocalcin, a late

marker of osteoblastic phenotype, were higher in cells growing

on coated Polished surfaces, but were respectively lower or

unchanged on SLA.

Conclusions and clinical implications: Taken together these

results show that adsorbed Periostin can improve cell

responses to titanium surfaces. However surface topography

can affect the cellular effects of this protein, most likely by

impairing its adsorption. Alternative methods for surface func-

tionalization must be therefore researched, to ameliorate

Periostin effects on rough titanium.


Initial density affects the resorption of boneblock allografts

Simone Lumetti,1 Claudio Marchetti,2 Ugo Consolo,3

Luigi Piersanti,2 Alessandra Multinu,3 GiuliaGhiacci,1 Carlo Galli,1 Guido Maria Macaluso1

1University of Parma, Parma, Italy, 2University of Bologna,

Bologna, Italy, 3University of Modena and Reggio Emilia, Modena

and Reggio Emilia, Italy

Background: Bone graft composition and microarchitecture

strongly affect their biological behavior. Density represents a

quantifiable parameter which may be related to the resorption

pattern, as denser cortical grafts may perform differently from

less dense trabecular grafts.

Aim: The aim of this study was to retrospectively evaluate

the correlation between initial density and 6 months resorp-

tion of autologous and fresh-frozen bone grafts used for hori-

zontal ridge augmentation.

Methods: Thirty-eight grafts were performed, 17 of autologous

bone and 21 of fresh-frozen bone. Autologous bone blocks

were harvested from intraoral sites, while homologous blocks

from tibial hemiplateau were provided by Banca del tessuto

muscolo-scheletrico (IOR, Bologna, Italy). Patients received

CT scans respectively 1 week and 6 months after surgery,

which were used for density and volume analysis. Student’s

t test was applied to evaluate differences in density change.

Linear regression analysis and Pearson correlation test were

used to investigate the correlation between parameters. The

level of significativity was set at P < 0.05.

Results: The mean initial density of homologous bone grafts

was (708 ± 335 HU) and it resulted to be significantly lower

(P = 0.0099) than the density of autologous bone grafts

(998 ± 232 HU). The mean density variation was 9% in the

control group and 8% in the test group. No significant differ-

ences were observed in density changes between the groups

(P = 0.57). The Pearson test revealed that no correlation

between inital density and degree of resorption existed for

autologous bone grafts, while such a correlation was signifi-

cant for fresh-frozen bone grafts. Less dense grafts tended to

lose more volume than denser grafts: average volume resorp-

tion for 800 HU (P = 0.001).

Conclusions and clinical implications: Fresh-frozen bone grafts

used in this study had a wide density range, depending on the

portion of tibia they come from: this fact made possible to

highlight a correlation between initial density and volume

change. On the other hand, autologous bone grafts had a lim-

ited density range and this may have hindered the possibility

to show such a correlation, which has been reported in previ-

ous studies. Basing on these data, we may conclude that bone

grafts with a density >800 HU are preferable to less dense

grafts, due to their lower degree of resorption. Further studies

which analyze the behavior of autologous bone grafts with awider density range are recommended.


Platelet rich fibrin (PRF) as a matrix for humanosteoblast cell cultivation

Volker Gassling,1 Nicolai Purcz,1 Jürgen Hedderich,2

Timothy Douglas,3 Yahya Acil,1 Jörg Wiltfang1

1Department of Oral and Maxillofacial Surgery, University

Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany,2Institute of Medical Informatics and Statistics, University

Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany,3Department of Organic Chemistry, University of Ghent, Ghent,

Belgium, Gent, Belgium

Background: An essential precondition for new bone formation

is an extracellular matrix in which osteoblastic cells can

migrate, differentiate and proliferate. Platelet rich fibrin (PRF),

a biopolymer has been shown to support the bone regeneration

in clinical applications.

Aim: The aim of this in-vitro study was to assess whether

membranes or clots of PRF promote the proliferation and dif-

ferentiation of osteoblast cells.

Methods: Human osteoblasts were cultivated on PRF clots,

PRF membranes or collagen membranes ( n = 10 per group).

The alkaline phosphatase activity (ALPA), a marker of osteo-

blast differentiation, was measured in the supernatant over a

period of 36 days. Osteoblast cultures with eluates of PRF

membranes ( n = 7) and collagen membranes ( n = 8) were used

to analyse cytotoxicity and proliferation promoting effects

with the lactate dehydrogenase (LDH) test and BrdU (5-bromo-

2-deoxyuridine) test, respectively. Proliferation of human

osteoblasts cultured on platelet rich fibrin membranes or

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collagen membranes was analysed by the water soluble tetra-

zolium (WST-1) test.

Results: The increase of ALPA as an indicator of osteoblastic

differentiation was higher in cultures on PRF clots and mem-

branes compared to collagen membranes. The BrdU test

showed a higher proliferation of human osteoblasts cultured

with eluates from PRF membranes than with eluates from col-

lagen membranes, respectively. This is in accordance with the

findings of the WST-1-proliferation test that showed highercell proliferation for the human osteoblasts cultured on PRF

membranes than on collagen membranes.

Conclusions and clinical implications: PRF clots and mem-

branes has been shown to be suitable as scaffold for human

osteoblast cell cultivation.


Keratinized tissue augmentation by means of anew matrix

Carlo Maiorana, Alessandra Gatto, Luca Pivetti,Mario BerettaDepartment of Dental Implants, Fondazione IRCCS Cà Granda,

University of Milan, Ospedale Maggiore Policlinico, Milan, Italy

Background: A good level of keratinazed tissue is not proven

to effect implant success rate, but is important for oral

hygiene procedures. Nowadays there are three different kind

of graft that can be used to achieve gingival augmentation:

autogenous, allogenic and xenogenic grafts. The last group is

generally of bovine or porcine origins. This kind of grafts are

deprived from cellular components, but preserve extracellular

matrix, collagen and elastic fibres, therefore presenting thesame regenerative capabilities.

Aim: The purpose of this investigation was to study the clini-

cal results utilizing a collagen matrix as a substitute for soft

tissue autografts in patients restored by conventional prosthe-

sis or implant-based prosthesis, where a vertical and horizon-

tal increase of keratinized soft tissue is necessary.

Methods: The surgery starts with a split thickness longitudi-

nal incision, followed by two lateral incisions. The coronal

edge of the mucosal flap is fixed to the periosteum in the

depth of the vestibule. The exposed area is covered with the

collagen matrix (Mucograft®, Geistilich Pharma AG, Wolhu-

sen, Switzerland), which is stitched with nylon sutures. Half

of the stitches will remain for 4/6 weeks to determine the out-

line of the incision, this is important to evaluate the re epithe-

lization. An acrylic splint is placed upon the surgical site and

remains on site for 10 days in order to avoid muscular inser-

tion migration in a coronal direction. Patients are controlled

at 3, 10 days, 2, 3, 4, 8 weeks and then at 6 months after the

surgery. During every visit the amount of keratinized tissue

gain as well as re epithelization and contracture of the graft

are measured and photographed.

Results: In the 10 patients treated re epithelialization was

complete at 4 weeks. The 20 measures collected after

6 months showed less than 20% contracture (considered as

excellent), while the other 12 were found inferior to 50%

(good). Clinically it has been observed a level of regenerated

keratinized tissue as the adjacent areas. The regenerated tissue

looks smooth, without any dyschromia, and a nice vascular

network can be appreciated. All subjects reported low discom-

fort, identified as a level 1 of Mankosky pain scale.

Conclusions and clinical implications: Matrix resorption is slow

enough to lead re epithelization and guarantee a deeper vesti-bule, therefore to reach healthy and aesthetical success. This

last aspect in particular is enhanced by a perfect tissue inte-

gration. In addiction, post-surgical morbidity is very little

compared to autogenous soft tissue grafting techniques


Effect of low level laser irradiation on bonemarrow mesenchymal stromal cells for bonetissue regeneration

Marco Giannelli,1 Alessandro Pini,2 Chiara Sassoli,3Flaminia Chellini,3 Roberta Squecco,4 BenedettaMazzanti,5 Daniele Bani,3 Lucia Formigli3

1Odontostomatologic Laser Therapy Center, Florence, Italy,2Preclinical and Clinical Pharmacology,, Florence, Italy,3 Anatomy, Histology and Forensic Medicine, Florence, Italy,4Physiological Sciences, Florence, Italy, 5Haematology, Placental

Blood Bank, Careggi Hospital, Florence, Italy

Background: Reconstruction and rehabilitation of acquired

defects or loss of teeth of the oral cavity is an important

dental service. Severe deformities of the bone due to trauma,

atrophy or periodontitis injuries may cause alveolar bone and

soft tissue reduction and interfere with implant-prosthetic

rehabilitations. Mesenchymal stromal cells (MSCs) have been

shown to be a promising source of adult stem cells for cell

transplantation and bone repair/regeneration. The use of these

cells in cell therapy requires their expansion in vitro in order

to obtain an adequate amount of cells to be implanted in the

injured tissue. Therefore, improvements of their proliferative

potentials during in vitro culture can significantly shorten cell

preparation time and avoid contamination, thus contributing

to the further development of cell-based tissue regeneration.

Low-level laser irradiation (LLLI) may represent a promising

approach to stimulate cell proliferation.

Aim: In the present study we investigated the effects of635 nm diode laser on mouse MSC proliferation and the

underlying cellular and molecular mechanisms.

Methods: Mouse bone marrow mesenchymal stromal cells

(MSCs) were isolated from femura and tibiae of male C2F1

mice. MSCs in growth medium were stimulated with a diode

laser 635 nm in continuous irradiation mode (power 89 mW;

energy density dose of 0.26 J/cm2; laser output was coupled to a

0.6-nm-diameter optical fiber) and assayed for cell viability and

proliferation by MTS assay, Time lapse videomicroscopy and

EdU incorporation. Expression of Notch-1 and its target gene

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Hes-1 were evaluated in MSCs cultured in the absence or

presence of 0.5 mM Ba2+, to inhibit KCa1.1 chennels, using RT-

PCR, Western Blot and confocal immunofluorescence Ionic cur-

rents were recorded with the whole-cell patch clamp technique.

Results: It was found that MSC proliferation was significantly

enhanced after laser irradiation and this phenomenon was

associated with the up-regulation and activation of Notch-1

pathway, and with increased membrane conductance through

voltage-gated K+, BK and Kir, channels and T-and L-type Ca2+

channels. We also showed that MSC proliferation was maily

dependent on Kir channel activity, on the basis that the cell

growth and Notch-1 up-regulation were severely decreased by

the pre-treatment with the channel inhibitor Ba2+ (0.5 mM).

Interestingly, the channel inhibition was also able to attenu-

ate the stimulatory effects of diode laser on MSCs, thus pro-

viding novel evidence to advance our knowledge on the

mechanisms of biostimulation after LLLI.

Conclusions and clinical implications: In conclusions, our find-

ings suggest that diode laser (630 nm) may be a valid and safe

approach for the preconditioning of MSCs in vitro prior cell

transplantation for bone repair and regeneration.


Thickening of peri-implant mucosa usingpunched gingival graft

Dušan Grošelj,1 Astrid Raz ˇ em,2 MatejaŽvokelj-igličar,3 Helena Grošelj1

1MEGFID d.o.o., Ljubljana, Slovenia, 2 ARDENS d.o.o., Koper,

Slovenia, 3PREMI-LINK d.o.o., Naklo, Slovenia

Background: Computer-guided flapless surgical approach is amethod by which one can precisely position implants using

laboratory-fabricated surgical templates acquired from CT

scans without reflecting a flap and merely through the oral

mucosa. The flapless minimally invasive implant surgery has

numerous advantages including better preservation of circula-

tion, soft tissue as well as bone volume at the site. As data

accumulate, dentists are learning that this method shortens

the time of surgery, increases patient’s comfort, accelerates

healing and allows oral hygiene immediately following sur-

gery. The clinicians are mostly of the opinion that long-term

health and stability of the peri-implant soft tissues is possible

with the presence of adequate soft tissue thickness or

recommended 2.5 – 3 mm of keratinized gingival tissue (KGT)

surrounding an implant restoration. A thin gingival biotype

may serve as locus minoris resistentiae for development of

soft tissue defects in the presence of biofilm-induced inflam-

mation or tooth brushing trauma.

Aim: To preserve a deepithelized punched gingival graft

excised during flapless surgery in computer-guided implant

placement and to assess augmentation of KGT and/or local-

ized defect of collapsed alveolar ridge.

Methods: In one female and five male patients, mean age

65.2 ± 9.9 years, eight small horizontal crestal incisions were

placed in the alveolar mucosa facial or lingual to the tightened

implant already. These pouch-like preparations were performed

where lack of keratinized gingiva or localized deficiency of bone

and soft tissue was found. At the start of flapless implant place-

ment a punched gingival tissue taken with trephine (4 mm in

diameter) was deepithelized and preserved in saline. Finally,

this connective graft was placed into the pouch in order to gain

the apico-coronal augmentation of soft tissue profiles.

Results: 6 – 36 months after mucogingival therapy, =16.0 ± 11.8 months, seven cases demonstrated increase in the

width of KGT in apico-coronal direction reaching =

2.8 ± 0.4 mm where previously the thickness was inadequate.

The probing pocked depths of controlled sites were

= 2.4 ± 0.9 mm. The last patient showed marked gain

and improvement of earlier deficient soft tissue profile

6 months after treatment.

Conclusions and clinical implications: Our preliminary data sug-

gest that preserved punched deepithelized gingival tissue grafts

integrate well and gingiva reaches adequate thickness and KGT

width few months after surgery. This contributes to improved

maintenance of stable peri-implant soft tissue environment.


Clinical and tomographic analysis of the increasein height and implant success after sinus lift: a2-year follow-up

Jéssica Gulinelli,1 Edilson Ferreira,2 Marcos Kuabara,2

Bruno Vieira,2 Renato Andrade,2 Natália Neiva,2

Ricardo Oliveira2

1Sagrado Coração University, Bauru, Brazil, 2Imppar

Odontologia, Londrina, Brazil

Background: Maxillary sinus lift procedures with autogenous

bone grafting or synthetic and implant placement have been

extensively documented and reviewed. The residual crestal

bone height as one of the most critical factors influencing

implant survival rate.

Aim: The aim of retrospective investigation was to evaluate

by means of computerized tomographic scans the increase in

height after sinus floor augmentation with different bone

grafting materials and implant clinical success after 2-year fol-

low-up.

Methods: Forty-five patients (24 female, 21 male) aged

between 29 and 84 years-old were undergone maxillary sinus

lift procedures. The cavitieswere filled with particulate bone

autogenous of retromolar area, anorganic bovine bone (Geistlich

Bio-Oss®), association of autogenous/anorganic bovine bone or

simultaneous implant placement with sinus lift and anorganic

bovine bone. After 6 – 8 months the implants were placed and

measured torque values. The implant survival was defined

when the prosthesis had been delivered and followed for

2 years without infection, pain, or more than 2-mm periim-

plant bone loss. The computed tomography scans taken before

and 6 – 8 months after elevation surgery. The height of bone

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formation was calculated using the Somaris Sienet Magic

View software. The data were analyzed with paired t-test and

non-parametric test (P = 0.05) using the Graph Pad Prism 4.0.

Results: The results showed a statically significant difference

in height after 6 – 8 months (P < 0.001), represented by a med-

ium increase of 7.07 mm. A total of 86 fixtures were followed

for more than 2 years after prosthesis delivery. Among the

biomaterials used in the completion of the cavities of patients,

51.2% were autogenous bone, 24.4% anorganic bovine bone-and 24.4% association among these two materials. In five

cases the maxillary sinus presented bone septa and in seven

patients simultaneous implant placement withsinus floor ele-

vation. All the implants presented connection of external

hexagon, the medium size of the implants was of 10 mm of

height and the torque medium of insert was of 25 Ncm. One

patient developed sinusitis and two implants were lost. The

2-year survival of fixture was 97.68%.

Conclusions and clinical implications: The height obtained with

the elevation was effective for the installation of the implants

in the maxillary. Both delayed and immediate placement of

implants can be used safely for sinus lifting. There were nostatistically significant differences between the various graft

materials.


Computertomography-based evaluation ofvolumetric changes after sinus flooraugmentation

Markus Hof, Bernhard Pommer, Michael Girardi,Patrick Heimel, Georg Watzek, Werner ZechnerDepartment of Oral Surgery, Bernhard Gottlieb University of

Dentistry, Vienna, Austria

Background: Maxillary sinus floor augmentation through a

lateral approach is the most frequently used method to

increase bone height in the posterior maxilla to allow for

implant placement. However, substantial resorption of autolo-

gous bone grafts occurs during healing. Addition of Bio-Oss®

granules may reduce graft resorption, thus improving graft

stability.

Aim: The aim of the present study is to assess volumetric

changes of different ratios of grafting material for maxillary

sinus floor augmentation using computed tomographies.

Methods: Postoperative computed tomographies were available

from 31 sinus floor augmentations (25 patients). Computed

tomographies of the maxillary sinuses were obtained postoper-

atively, after 14 days and 5 months, respectively. Different

ratios of Bio-Oss® to autologous bone were used for grafting

through a lateral approach. Volumetric changes of the grafts

were evaluated using the Definiens Developper XD software.

Results: Mean graft volume after 14 days and 5 months was

1.7 cm3 (± 0.8 cm3) and 1.5 cm3 (± 0.8 cm3), respectively.

Based on volumetric measurements of the grafts mean shrink-

age was 16%. The volumetric reduction was significantly

influenced by the ratio of Bio-Oss® and autologous bone

(rs = 0.52, P < 0.001). No influence of age, gender and Bio-

Oss® particel size was observed.

Conclusions and clinical implications: Within the limits of the

study, the results indicate a significant reduction of graft vol-

ume after 5 months of healing. Higher percentages of Bio-

Oss® resulted in reduced graft shrinkage. However, further

studies are needed to assess the optimized ratio of Bio-Oss®

and autogenous bone to achieve long-term graft as well asimplant stability.


Semilunar miniblock technique for facial socketwall preservation

Andriy Huk“Perfect Dent” Clinic, Lviv, Ukraine

Background: Prevention of facial bone wall resorption in

postextraction sockets is one of the most challenging taskswhen performing immediate implant placement. Due to some

known biological reasons, socket walls remodel (Araujo 2005)

and this results in loss of alveolar ridge dimensions (Van der

Weiden 2009). This, in turn, leads to flattening of the convex

facial ridge profile even when “socket preservation” is per-

formed (Fickl et al. 2009, Ten Heggeler 2010) which can cause

aesthetic problems.

Aim: Objective of this study was to evaluate efficiency of pre-

serving facial bone wall after immediate submerged implant

placement into extraction socket utilizing small size semilu-

nar cortical bone blocks.

Methods: The study comprised 10 patients treated with dentalimplants placed into fresh postextraction sockets simulta-

neous with small intraoral block bonegrafts. Implant bed prep-

aration was performed according to common 3D positioning

rules. The cortical bone grafts were harvested with a trephine

bur 3.8, 5 or 6 mm in diameter, which was used to make two

trephine holes in overlapping manner to the depth of 2 – 4 mm.

Donor sites were chosen as follows: palatal bone at region of

teeth 12 – 14, base of the alveolar process between teeth 11 – 13

at the facial side, external oblique line, retromolar area. Semi-

lunar cortical grafts were placed inside the socket from vestib-

ular side to the future implant position and facing the buccal

bone. Block stability was obtained by pushing it apically into

the socket using flat osteotome and bone mallet. Due to the

tapered contours of the socket, block became stuck in inti-

mate contact with bone walls. All remaining gaps between

implant and block were filled with autogenous bone chips

mixed with DBBM. A submerged protocol was chosen.

Peri-implant bone level was measured after a healing period of

2 – 4 months. Ridge volume at grafted sites was evaluated at

CT scans and itraoperatively during uncovery phase and

compared to preoperative values.

Results: The study involved 12 sockets at maxillary and man-

dibular premolar and molar sites. No complications were

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observed during healing period neither at donor nor at grafted

sights. The buccal bone contour became stable comparing to

initial situation. The mean overall horizontal bone loss after

healing was 0.6 mm. Vertical bone margin became stabilized

at the level of implant shoulder or within 1 mm above it.

Conclusions and clinical implications: Within the limits of this

study, proposed method of socket grafting shows the possibil-

ity to eliminate postextraction facial bone changes thus

improving natural view of implant-supported restorations.


Bio-Oss and stem cells from bone marrowobtained from the distal femur for sinus grafting

Juan Carlos Ibañez,1,2 Juaneda Maria Agustina,1,2

Maria Constanza Ibañez,1,2 Martin Ignacio Ibañez2

1Universidad Catolica de Cordoba, Cordoba, Argentina, 2Private

Practice, Có rdoba, Argentina

Background: Sinus grafting has become a common procedureto obtain adequate height for implant placement in the poster-

ior maxilla. High success or survival implant rate, reduction

of healing time and obtaining a high percentage of vital bone

may be primary objectives when this technique is applied.

Aim: This investigation was design to test if the combination

of grafting material Bio-Oss and bone marrow obtained from

the distal femur with high concentration of stem cells is

capable to be used for sinus grafting obtaining high success/

survival rate and high percentage of vital bone.

Methods: Fifteen sinus grafting procedures were performed in

nine patients. Residual bone width and height was measure.

All the procedures were performed using a lateral approachwith piezo surgery. Ten to 15 cc. of bone marrow with stem

cells was obtained from the distal femur using an appropriate

trocar and aspirate with a syringe without any anti-coagulants.

After eliminate the excess of plasma the bone marrow was

mixed with Bio-Oss (spongiouse large particles) and used to

full fill the space obtained by the elevation of the sinus

mucosae. The lateral window was covered with resorbables

membranes. After 6 – 9 months of healing, 31 double acid-

etched surface implants were placed. RFA analysis was used

to measure initial stability. Six implant sites were created

with 3.5 mm. trephines in order to obtain vertical biopsies for

histological and histomorphometric analyses. After 4 –

6 months implants were loaded.

Results: All the sinus procedures had an uneventful heal.

Twenty-nine implants were successful and a mean of 38% of

vital bone was obtained at the time of implant placement.

The mean ISQ obtained at implants placement was 62.3 and

60.8 at implant loading

Conclusions and clinical implications: Due the results of this

preliminary report, the use of a mixture of Bio-Oss with

bone marrow obtained from the distal femur seems to be an

efficient combination to obtain an adequate percentage of

vital bone when sinus lifting is performed and for obtaining

good results when implants with microtextured surface are

used.


Evaluation of augmented bone over exposedimplants threads, three years follow-up

Atef IsmailPrivate Practice, Cairo, Egypt

Background: In implant placement post extraction in most of

the cases diameter of the implant is not coincide with the

existing socket, yielding a space or a gab and most of the cases

need augmentation. Different materials and techniques can be

used to treat such dehiscence or even fenestration. The quality

and the volume of the augmented bone over the exposed

implants threads is a challenge for maintaining soft tissue

support for long time

Aim: Clinical and radiographic evaluation of augmented bone

over exposed implants threads in the treatment of dehiscenceand fenestration.

Methods: Eighteen patient (ten Female, eight Male) indicated

for extraction, indicated for implant therapy. All patients

receive single implant post extraction, yielding horizontal

defect more than two millimeters. All patients received same

type of implants. All exposed threads were counted from the

top of implant to the buccle margin of the bone. All the

exposed threads covered with DUO-TECK® membrane using

housing technique. Four months later secondary surgery was

performed including measurements of exposed threads num-

bers. All patients received X-ray radiographic evaluation at

4 months, 1 year, 2 years, 3 years.Results: In this study all the defects have horizontal bone

defects more than 2 mm exposed threads from 3 to 9. In this

study all implants were successfully osseointegrated with a

complete coverage of implants threads was seen from 17 to 18

sides. Two cases show bone growth over the covering screw.

One side show from 1 to 2 exposed threads of total eight

threads. Radiographic analysis of augmented bone over

exposed threads evaluated and the mean crestal bone level

change for 1 year was 0.55 ± 0.10 in the first year. Mean mar-

ginal bone crestal bone resorbtion of the augmented bone over

the exposed threads is 1.01 mm during the third year.

Conclusions and clinical implications: The results of this clini-

cal study show it is possible to gain bone coverage over the

exposed implants threads by using DUO-TECK membrane.

Augmented bone gain show crestal bone loss at 3 years post

restoration within the commonly accepted measurements.

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Usefulness of alveolar distraction osteogenesisfor dental implant of mandible

Masahiro Iwata, Minoru Murayama, ToshihiroNishioka, Yoshihiro Tanimoto, Hiromi Kasai,Yoko Asai, Akihito Matsuno, Yukihisa KokubaKishiwada tokushukai Hospital, Kishiwada, Japan

Background: Vertical alveolar distraction osteogenesis is an

efficient method for augmentation prior to inserting dental

implants. But a relapse of the transport segment and decrease

in bone height before implant placement is common.

Aim: In this study, we evaluated this alveolar distraction

osteogenesis before implant placement, investigated the

relapse in bone height.

Methods: The subjects were 34 patients, ranged in age from 21

to 65 years with the defect of the mandible (19 males and 15

females). In all cases we treated by vertical alveolar distraction

osteogenesis. Active distraction was started after a latency per-

iod of 3 days with a rate of 0.5 mm twice daily. After the end

of alveolar distraction osteogenesis, length of consolidation

was 3 months, and distractors were removed. Bone height was

measured on digital orthopantomographic radiographs, after

distraction and before implant placement.

Results: Mean alveolar distraction was 14.5 mm. The mean

relapse was 19% (13% to 27%) after the end of consolidation.

One month after distractor removal, 10 patients were per-

formed implant placement (Group A). The mean relapse was

5% (1 – 7%) at implant placement. On the other hand, 24

patients were performed distractor removal and implant place-

ment at the same time (Group B).Conclusions and clinical implications: The vertical alveolar dis-

traction osteogenesis before dental implant placement is very

useful but a considerable relapse must be confronted. This

study indicated that implant placement performed at the same

time of distractor removal if possible.


Osseointegration of the implants placed in thereconstructed bone

Shiho Kajihara,1 Kazuya Doi,1 Takayasu Kubo,2

Koji Morita,1 Kazuhiko Hayashi,1 Hiroshi Oue,1

Yasumasa Akagawa1

1Department of Advanced Prosthodontics, Hiroshima University

Graduate School of Biomedical Sciences, Hiroshima, Japan,2Clinic of Oral Implants, Hiroshima University Hospital,

Hiroshima, Japan

Background: When implant fixtures are lost or a large bone

defect locates at implant placement area, it is necessary to

apply autogenous bone and artificial bone such as hydroxyapa-

tite (HA) for bone reconstruction. However, the reports of

osseointegration at reconstructed area with HA are few.

Aim: This study evaluated the aspects of osseointegration of

the implants placed in the reconstructed bone by intercon-

nected porous calcium hydroxyapatite (IP-CHA).

Methods: This study design was approved by the Research

Facilities Committee for Laboratory Animal Science at Hiro-

shima University School of Medicine. Cylinder-type IP-CHAs(75% porosity, diameter: 4.3 mm, height: 10.0 mm, NEO-

BONEⓇ, Covalent Materials, Japan) as a bone graft material

was placed into eight bone sockets (diameter: 4.3 mm, depth:

10.0 mm) at both sides of the femur of four male HBD Dogs

(weight: 20 – 25 kg). IP-CHA at the left side was a 24-week sam-

ple. After 12 weeks of IP-CHA placement, titanium implant

(diameter: 3.3 mm, length: 10.0 mm, Br mark System MkIII

TiUniteⓇ, Nobel Biocare, Sweden) was placed into half side of

the IP-CHA at the right femur. (A half portion of the implant

was contacted to the reconstructed IP-CHA and a half of the

femur itself). IP-CHA was also placed into the another bone

socket as a 12-week sample. Implant placement was performedby Br mark SystemⓇ protocol. After 12 weeks of implant place-

ment, dogs were sacrificed and the bone tissues involved the

implant and or not were obtained. The block without implant

was decalcified and stained with HE. The block with implant

was prepared as undecalcified polishing specimens and stained

with toluidine blue. These samples were examined histologi-

cally with a light microscope. The ratio of bone formation at

cortical bone area of the femur was measured histomorphomet-

rically at 12- and 24-week decalcified samples and bone-

implant contact (BIC) ratio was measured histomorphometri-

cally at 12-week undecalcified samples.

Results: New bone formation was observed in both of the host

bone and IP-CHA sides. Implant and IP-CHA were integrated

with osseoconduction. Histomorphometrically, new bone for-

mation area was superior in the IP-CHA 24-week sample

rather than IP-CHA 12-week sample. From the BIC ratio,

osseointegration was achieved at the surface between implant

and IP-CHA. Osseointegration was obtained around the

implant in reconstructed bone by IP-CHA.

Conclusions and clinical implications: Based on the limited

results of this study, IP-CHA cylinder might be expected to be

a possible bone graft material to reconstruct bone for implant

placement.

513 Posters –

Tissue Augmentation andEngineering

Suitability of PEG-membrane combined withBCP in extensive SFEs

Philip L. Keeve,1 Adrian Lucaciu,1 Anton Friedmann1

1Department of Periodontology, Witten/Herdecke University,

Witten, Germany

Background: Most recent consensus considers non-resorbable

grafting materials suitable for SFE procedures either used

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alone or in combination with autologous bone (AB) particles.

The handling of lateral window for accessing sinus cavity is

under discussion. However, various membranes have been

suggested for covering the access window from lateral before

re-suturing the flap tissue.

Aim: The aim was to observe how the newly introduced in situ

forming polyethylene glycol (PEG-) membrane (MembraGel®,

Institut Straumann AG) performed for effectively secluding the

sinus cavity and laterally augmented areas; both grafted by BCP(Bone Ceramic®, Institut Straumann AG) used without AB.

Methods: Three calibrated periodontists from Department of

Periodontology (Witten/Herdecke University) contributed to a

total number of 15 sites in 13 patients. The surgical protocol

was standardized among all patients consisting of two stage

approach; sinus floor elevation combined with a lateral ridge

augmentation followed than by implant placement 6 – 9 months

later. SFEs were performed according to original technique by

Tatum (1986). BCP moistured with saline was used exclusively

in all sites being covered by layer of PEG material. After setting

of membrane material a combination of horizontal mattress

and single sutures stabilized the flap margins; tension free adap-tation of the flap was achieved by releasing periosteum. Radio-

graphic controls were performed before augmentation and after

healing period prior to implant positioning. Post-augmentation

regimen included pain medication and systemic antibiotics

(Amoxicillin, 1000 mg) and regular mouth rinses (CHX). All

patients were monitored on weekly basis during first month of

healing clinically and photographs taken. Core biopsies were

harvested at implant placement and proceeded histologically.

Results: Soft tissue healing was clinically uneventful without

execeptions. There were non dehiscences and/or membrane

perforations detected. Newly formed hard tissue volume

appeared optimized in vertical and lateral dimensions. Quan-

tity of new mineralized tissue was adequate for placing either

standard or wide body diameter implants (RN® or WNI®,

Institut Straumann AG). Length of implants used varied from

8 to 12 mm and bone quality was clinically classified as

D1-D2. All surgically created shafts demonstrated adequate

vascularization. In all implants primary stability was

achieved. All implants inserted were well integrated.

Conclusions and clinical implications: Elevating the sinus floor

in presence of 1 – 5 mm of residual bone using BCP alone in

combination with synthetic biodegradable membrane for the

lateral window was sufficient to form new bone and to

enhance the alveolar ridge volume for implant placement and

integration in the deficient posterior maxilla.


Clinical application of platelet-rich fibrin by theapplication of the Double J technique in alveolarbone defect areas

Su-gwan Kim,1 Jin-son Kim,2 Moon-hwan Jeong,3

Ji-su Oh1

1Chosun University, Gwangju, Korea, 2Misomore Dental Clinic,

Jeonju, Korea, 3Dallas Dental Clinic, Seoul, Korea

Background: Platelet-rich fibrin (PRF) belongs to a new genera-

tion of platelet concentrates, with simplified processing and

without biochemical blood handling. PRF releases growth fac-

tors andmatrix glycoproteins. The Double J technique, which

uses centrifuged venous blood that is sampled using two dif-

ferent types of DB vacutainers, is a procedure that covers the

PRF matrix obtained from one of the DB vacutainers on trans-

planted osseous coagulum, which is obtained using the plasma

layer and buffering layer from the second DB vacutainer.

Aim: In our study, the Double J technique that uses platelet-

rich fibrin (PRF) was used to utilize the implant placement in

the alveolar bone defect area.

Methods: The surgical procedure is as follows: (1) Although it

is different depending upon the size of defect areas, generally,

approximately 30 ml of blood is collected. (2) The collected

blood is added to two different types of DB vacutainers. Of the

30 ml of blood, 10 ml of blood is added to a polypropylene DB

vacutainer without silica coating, and 20 ml of blood is added

to two DB vacutainers coated with silica, 10 ml in each. (3)

To balance the center of gravity, another DB vacutainer is pre-

pared containing 10 ml of water. The 4 DB vacutainers are

inserted into a centrifuge (Gyrozen 406G, Republic of Korea).They are centrifuged at 400 G (or 1750 rpm) for 10 min. The

interval from blood to centrifugation is minimized. (4) After

centrifugation, the plasma layer and the buffy coat layer con-

tained in polypropylene tubes without silica coating is aspi-

rated with syringes and mixed with bone graft materials that

are prepared in advance. After approximately 5 min, coagu-

lants that are suitable to bone graft are formed. (5) The formed

bone graft coagulants are applied to the bone defect areas and

covered with the PRF matrix (Fig. 3), and a primary suture

without tension is placed.

Results: When the technique was utilized with the implant

placement in the alveolar bone defect area, good results were

obtained.

Conclusions and clinical implications: It is thought that PRF is

a very useful material for the restoration of alveolar bone

defects that are commonly detected at the time of the implant

placement in edentulous areas.

Acknowledgment: This study was supported by a grant of the

Korea Healthcare technology R&D Project, Ministry for

Health, Welfare & Family Affairs, Republic of Korea.

(A091220).

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BMP2-delivering heparinized-titanium implantwith enhanced antibacterial activity andosteointegration

Deok-won Lee, Tae-hee KimKangdong Gu, Seoul, Korea

Background: Insufficient bonding of implants to bone tissues

and bacterial infections lead to the failure of titanium (Ti)-

based orthopedic and dental implants.

Aim: The aim of this study is to develop novel Ti implants

that enhance osteoblast functions, while simultaneously

decreasing bacterial infections.

Methods: First, the surface of pristine Ti was functionalized

with heparin-dopamine by mimicking a mussel adhesion

mechanism. Gentamicin sulfate (GS) and/or bone morpho-

genic protein-2 (BMP-2) was then sequentially immobilized to

the heparinized-Ti (Hep-Ti) surface. The compositions of pris-

tine Ti and Hep-Ti with or without gentamicin and/or BMP-2

were characterized by X-ray photoelectron spectroscopy (XPS)

and the growth of Staphylococcus aureus on the substrates

was assayed. Osteoblast functions of all Ti substrates were

investigated by cell proliferation assays, alkaline phosphatase

(ALP) activity, and calcium deposition.

Results: The results showed that the growth of bacteria on

GS/Hep-Ti and GS/BMP-2/Hep-Ti was significantly lower

compared to that on the pristine Ti and BMP-2/Hep-Ti. In

addition, BMP-2/Hep-Ti and GS/BMP-2/Hep-Ti significantly

enhanced ALP activity and calcium mineral deposition of

osteoblast cells. Taken together, GS/BMP-2/Hep-Ti could

achieve the dual functions of excellent antibacterial activityand osteoblast function promotion.

Conclusions and clinical implications: Therefore, dual drug

(antibiotics and osteoinductive protein)-eluting Ti substrates

such as GS/BMP-2/Hep-Ti are a promising material for the

enhanced osteointegration and implant longevity in orthope-

dics and dentistry.


Morphologic analysis using Cone-Beam CT and

3D program in atrophic mandible for mandibularbody bone graft

Jae-yeol Lee,1 Jung-han Lee,1 Young-chae Noh,1

Yong-deok Kim,1 Jung-bo Huh2

1Department of OMFS, School of Dentistry, Pusan National

University, Yangsan, Korea, 2Department of Prothodontics,

Yangsan, Korea

Background: The donor sites mainly used as a source of autog-

enous bone graft include mandibular symphysis, ramus, man-

dibular body, etc. Among these donor materials, mandibular

body bone graft offer several advantages such as making intra-

oral approach possible for surgical access, facilitating the clini-

cian to operate in the same field as the recipient site, low

resorption rate and short healing period due to its cortical

characteristics, needless of horizontal osteotomy near the root

apex, less risk of nerve injury.

Aim: The aim of this study was to evaluate the morphology of

atrophic mandible using Cone-Beam Computed Tomography

(CBCT) for mandibular body bone (MBB) graft and to purpose theusefulness of MBB as a good donor site for autogenous bone graft.

Methods: The subjects consisted of 26 patients undergoing

mandibular body bone graft in atrophic mandible ( n = 26).

Using cross-sectional computed tomography (CT) images, the

distance of alveolar bone width, the distance from mandibular

canal to alveolar crest, the thickness of buccal cortical bone

and the distance from mandibular canal to buccal cortical

bone were measured at the premolar (PM), the first molar

(M1), the second molar (M2) and anterior border of ramus

(RM) of edentulous mandible.

Results: Average alveolar bone width were 6.25 mm (PM),

6.7 mm (M1), 7.51 mm (M2), 10.98 mm (RM). average alveolarbone height were 13.26 mm (PM), 12.67 mm (M1), 11.26 mm

(M2), 10.82 mm (RM). Cortical bone thickness were 1.96 mm

(PM), 2.29 mm (M1), 2.51 mm (M2), 2.59 mm (RM). Distance

from the mandibular canal to buccal cortical bone were

2.50 mm (PM), 4.31 mm (M1), 5.51 mm (M2), 6.28 mm (RM).

Conclusions and clinical implications: A 2.0 mm thickness and

from the first molar to the second molar about 20~ 25 mm

buccal cortical bone could be harvested at atrophic mandible.

Atrophic mandibular body bone graft is a safe technique and a

good donor site. Based on the results of the present study, sur-

geon can gain sufficient amount of cortical bone required for

bone graft, in spite of the patient’s atrophic stage of mandible.

In addition, by calculating the distance from the nerve canal

using pre-operative CBCT data and 3-D imaging program, the

safety of surgical procedure can be improved especially using

mandibular body bone graft or ramal graft.


Maxillary sinus floor augmentation procedure:Summers’ vs. a piezo-electric technique.

Robert Kirmeier,1 Michael Payer,1 Susanne Platzer,2

Nicola Bianco,1 Sebastian Kühl,1,3 Andreas Weiglein,4

Norbert Jakse11Department of Oral Surgery and Radiology, School of Dentistry,

Medical University Graz, Graz, Austria, 2Department of

Prosthodontics, School of Dentistry, Medical University Graz,

Graz, Austria, 3Clinic for Oral Surgery, Radiology, and Oral

Medicine, School of Dental Medicine University of Basel, Basel,

Switzerland, 4Institute of Anatomy, School of Dentistry, Medical

University Graz, Graz, Austria

Background: Sinus floor augmentation of the lateral maxilla is

a highly predictable and successful procedure. To increase

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bone volume prior to implant placement, different transcrestal

techniques can be used.

Aim: This cadaver-based study was designed to compare the

performance of hand instruments (Summers technique) vs.

piezoelectric devices (Sinus Physiolift® Mectron SpA, Carasco,

Italy).

Methods: Out of a number of 80 cadaver heads in Thiel’s fixa-

tion 16 undamaged and edentulous objects were selected for

computer tomographic scans. Schneiderian membrane eleva-tion was carried using either piezosurgery or conventional

hand instrumentation, which was assigned by lot. After simu-

lation of sinus augmentation by the use of a radiopaque

impression material (elite® implant medium, Zhermack, Italy),

a postoperative scan was carried out. All scans were processed

with computed tomography (Somatom plus 4, Siemens AG,

Bensheim, Germany). In three replicates a validated computer

software (Voxim, IVS Technology GmbH, Chemnitz, Germany)

was used to calculate augmentation volumes. Accuracy and

reliability of the volume measurements were assessed based

on the intra-class correlation coefficient. The non-parametric

Mann –

Whitney U -test was applied to calculate the differencesin augmented volume between the two methods. A P

value < 0.05 was considered to indicate statistical signifi-

cance.

Results: An intra-class correlation coefficient of 0.99 indicated

a close to perfect agreement of the volumetric quantification.

A mean graft volume of 0.29 ± 0.18 cm3 (0.07 – 0.60 cm3) was

measured for the Summers technique compared to 0.39 ± 0.32

cm3 (0.05 – 1.04 cm3) for the Sinus Physiolift® technique.

There is no significant difference in regards to trauma to the

Schneiderian membrane or augmented volume.

Conclusions and clinical implications: Both techniques generate

expedient augmentation volume in the posterior atrophic max-

illa. The piezoelectric technique can be recommended as an

alternative tool to graft the floor of human maxillary sinuses.


Autologous and fresh-frozen allogeneic blockbone grafts. A CBCT analysis

Tine Kjærgaard,1 Cæcilie Basse Eriksen,1

Rubens Spin-neto,1 Elcio Marcantonio Jr,3 AndreasStavropoulos,2,4 Ann Wenzel1

1Health, Department of Dentistry, Oral Radiology, Aarhus

University, Aarhus, Denmark, 2Health, Department of Dentistry,

Aarhus University, Aarhus, Denmark, 3UNESP – Univ. Estadual

Paulista, Araraquara, Brazil, 4CEPBR – Center for Experimental

and Preclinical Biomedical Research, Athens, Greece

Background: Cone Beam Computerized Tomography (CBCT)

may potentially be an efficient tool to evaluate the treatment

outcome after grafting procedures.

Aim: To estimate dimensional changes in autologous and

fresh-frozen allogeneic block bone grafts 6 months after alveo-

lar ridge augmentation by means of CBCT (i-CAT Classic),

and to evaluate the reproducibility of the measurement

method.

Methods: Twenty-six partially or totally edentulous patients

with insufficient alveolar ridge width, treated either with

fresh-frozen allogeneic bone (AL) or autologous bone (AT)

onlay block grafts prior to implant placement (13 patients

with 19 block grafts in each group), were included in this anal-

ysis. Two masked examiners measured (in duplicate – 2 weeks

apart) the alveolar ridge area on 2-D CBCT images of thegrafted regions, recorded prior to surgery and 14 days (14 d)

and 6 months (6 m) after grafting. Differences in alveolar ridge

area among the various observation times were evaluated

using repeated measures ANOVA followed by Tukey’s test,

and differences between tested graft materials using t-tests.

The inter- and intra-observer reproducibility was assessed

through Pearson correlation tests.

Results: Inter- and intra-observer reproducibility was high,

with no statistically significant differences between observers

or duplicate measurements. Significant increase in alveolar

ridge dimensions, allowing implant placement, was obtained

with both types of grafts 6 m after grafting; no significantdifferences in alveolar ridge area were observed between the

groups at the various observation times. However, graft

resorption in the AL group was significantly larger compared

to that in the AT group at 6 m (P = 0.04).

Conclusions and clinical implications: Although similar

amounts of alveolar ridge width were observed in the two

groups, significantly largerbone graft resorption was seen in

patients treated with fresh-frozen allogeneic bone than in

those treated with autologous bone 6 months following alveo-

lar ridge augmentation. Planimetric measurements of alveolar

ridge on CBCT images showed high reproducibility.


Transposition of tongue pedicle flap beforeimplantation at resected mandible due to tumour

Koc ˇ ar MihaDepartment of Maxillofacial and Oral Surgery, University

Clinical Center Ljubljana, Ljubljana, Slovenia

Background: Tongue pedicle flap (TPF) is known for recon-

struction after intraoral resection of squamous cell cancer and

underlying bone. A lot of times all teeth are removed during

primary resection due to location of primary tumour, caries

lesion of them or consequently radiotherapy. After curing pri-

mary disease for better rehabilitation good chewing function is

obligatory due to correct nutrition. TPF has not keratinized

mucosa what is unfavourable for tissue around implants

which supported prosthetics.

Aim: Aim of this pilot study is presentation of protocol for

preparing favourable soft tissue before implantation after pri-

mary operation and reconstruction with TPF in mandible.

Methods: Four consecutive patients (1 female/3 male), mean

age was 54 years (ranging 52 – 55) were reconstructed with TPF

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at the time of removing carcinoma. Two also got radiotherapy

due to protocol. Three had fully edentulous mandibles where

residual alveolar processes were covered with mobile mucosa,

lover vestibules were totally flat. Partial edentulous patient

had same clinical problems. Irradiated patients got hyperbaric-

oxygen therapy due to protocol before intervention. Vestibu-

loplasty in all mandibles were performed. Insertion of geniog-

lossus and geniohyoideus on mandible was detached and fixed

with trans-cutaneous suture over gauze tampon in submentalarea. Mucosa was dissected supra-periosteal, adjusted down

and sutured on periosteal. On stripped alveolar process prefab-

ricated acrylic plate was fixed with titanium screws. Wound

was healing by second intention under antibiotic therapy and

mouth hygiene was controlled with rinsing of iodine solution.

Sutures, acrylic plates were removed after 4 weeks. Two-stage

implants (2/2/4/4) were inserted 6 weeks after vestibuloplasty,

in one case temporization was done on four splinted implants.

Reopening was done at other three patients (2/2/4) after

4 months. Prosthetics removing/fixed (3/1) were delivered at

all patients by protocol after that period. Clinical control was

done every 3 months. X-rays were performed every year.

Results: In all cases favourable soft tissue conditions were

observed without disturbance of tongue movement. All

implants were integrated uneventfully in bone. Clinically

mucosa was less mobile, vestibules got better anatomical

appearance. Tissues around implants were stable with no

inflammation in 2-year period.

Conclusions and clinical implications: Combine of vestibulopl-

asty with prefabricated acrylic plate and transposition of geni-

oglossus and geniohyoideus insertion gave us better soft tissue

condition before implantation at patients who were surgically

treated due to oral carcinoma and reconstruction with TPF.

Due to small sample investigation should be prolonged and

further histological investigation should be done on new

formed mucosa.


Bone substitute plus enamel matrix derivative vs.autogenous bone in deep-wide intrabony defects:a pilot study

Stéphane Korngold,1,2 Stéphane Kerner,1,2

David Nisand,2 Philippe Bouchard1

1Rothschild Hospital, Paris, France, 2Private Practice, Paris,

France

Background: The use of autogenous bone graft results in a sig-

nificantly greater change in bone level and attachment level

than open flap debridement procedures. The use of enamel

matrix derivative may improve clinical attachment level

(CAL) gain and probing pocket depth (PPD) reduction. A sig-

nificant association between radiographic defect angle and

CAL gain has been shown. The use of bone grafting in the

treatment of deep-wide intrabony defects has been suggested

to avoid the collapse of the flap.

Aim: To compare the efficacy and safety of the combination of

a synthetic bone graft substitute (Straumann BoneCeramic®)

and an enamel matrix derivative gel (Straumann Emdogain®) vs.

autogenous bone graft alone (used as control) in the treatment

of deep-wide periodontal intrabony defects.

Methods: In this prospective, randomized, two-arm controlled

study, 18 consecutive patients with moderate to severe peri-

odontitis were enrolled. Experimental teeth were mandibular

molars, maxillary or mandibular premolars and canines exhib-iting a probing depth 5 mm with 1 or 2-wall morphology (at

least 2/3 of the defect). The depth of the intrabony defect was

at least 3 mm with an angle 25° as measured on radio-

graphs. The surgical technique was the same for both test and

control groups. In the control group the bone was harvested at

the ramus using the K-systemTM. Changein CAL measured at

six sites of the treated tooth between baseline and 12 months

was used to compare the two treatments. A difference of

1 mm between the treatment groups was regarded as non-

inferiority (CI95%). Secondary variables included PPD reduc-

tion and radiographic bone gain. Bone level was measured by

ImageJ.

Results: Ten patients (test) and eight patients (control) were

analyzed (mean age: 34.2 + /- 8.5 years, gender ratio M/F: 7/11).

The non-inferiority of the two treatments wasconfirmed by

the CI95% for CAL that ranged from 0.995 to 0.536 mm. The

mean gain in CAL observed 12 months postoperatively was

1.00 ± 0.81 mm for the test group and 0.77 ± 0.70 mm for the

control group, respectively. No significant differences were

found for PD and bone level gain.

Conclusions and clinical implications: The present data show

that a combination of a synthetic bone graft substitute and

enamel matrix derivative gel may improve the CAL gain as

well as autogenous bone graft in deep-wide periodontal intrab-

ony defects.


Osteocyte lacunar density and area in newlyformed bone of the augmented sinus

Ulrike Kuchler,1,2,3 Gerd Pfingstner,2 DieterBusenlechner,2,3 Toni Dobsak,2,3,4 Karoline Reich,2,3,4

Patrick Heimel,2,3,4 Reinhard Gruber1,2,3

1Department of Oral Surgery and Stomatology, School of Dental

Medicine, University of Bern, Bern, Switzerland, 2Department of

Oral Surgery, School of Dental Medicine, Medical University of Vienna, Vienna, Austria, 3 Austrian Cluster for Tissue

Regeneration, Vienna, Austria, 4Karl Donath Laboratory for Hard

Tissue and Biomaterial Research, Department of Oral Surgery,

Medical University of Vienna, Vienna, Austria

Background: Osteocytes, the most common cells of the bone

are buried in lacunae. Density and area of the osteocyte lacu-

nae changes with increasing maturation of the newly formed

bone. Evaluation of osteocyte lacunae can therefore provide

insights into the process of graft consolidation.

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Aim: The aim of this study was to evaluate the osteoinduc-

tive effect of rhBMP-2 coated BCP carrier system in rabbit

sinus model.

Methods: A total of 16 maxillary sinuses in eight male rabbits

was used to compare rhBMP coated BCP as the test group and

BCP alone as the control group. RhBMP-2 coated BCP was pre-

pared by adding rhBMP-2 solution (0.67 ml in 1.5 mg/ml buf-

fer) to 1 g of BCP granule and lyophilized in a freezer-drier.

The same amount of rhBMP coated BCP and BCP alone werebilaterally grafted at the maxillary sinuses, respectively. The

animals were sacrificed 2 and 8 weeks postoperatively. Radio-

graphic and histological analyses were performed.

Results: The augmented volume was statistically larger in the

test group than the control in 2 weeks. In histological finding

of 2 weeks, healing pattern of each group was different,

although there was histometrically no significant difference in

new bone. A seam of new bone was lining the reflected sinus

membrane, but most of grafted particles were encapsulated by

fibrous tissue in the test group. On the other hand, new bone

sprouted from the parent bone and bony window area in the

control. In 8 weeks, both groups showed similar bone forma-tion.

Conclusions and clinical implications: Within the limitation of

the study, it can be concluded that rhBMP-2 can stimulate the

osteoinductive potential of the sinus membrane at the early

stage of healing, although there was no significant superiority

in bone formation.


Biomaterials with various biodegradationpatterns in extraction socket: a histometric

in vivo study

Jung-seok Lee,1 Ji-youn Hong,2 Seong-ho Choi,1

Eun-kyoung Pang,2 Ui-won Jung,1 Chang-sung Kim,1

Kyoo-sung Cho,1 Chong-kwan Kim3

1Department of Periodontology, Research Institute for Periodontal

Regeneration, Yonsei University College of Dentistry, Seoul,

Korea, 2Department of Periodontology, Graduate School of

Medicine, Ewha Womans University, Seoul, Korea, 3Department

of Periodontology, Research Center of Orofacial Hard Tissue

Regeneration MRC, Yonsei University College of Dentistry, Seoul,

Korea

Background: Dimensional alterations of extraction socket is

well demonstrated, and some studies found that placement of

biomaterials in extraction socket modified marginal ridge

alteration of the socket. However, slowly resorbing biomateri-

als like bovine hydroxyapatite remained all over the defect

area even at 2 and 3 months after graft and seemed to alter

the healing process in coronal area of the socket. Whereas, fast

resorbing biomaterials like autogenous bone and tricalcium

phosphate had been mostly resorbed before the time that new

bone formation would occur at coronal area, and these resorp-

tion rates could affect the process of socket healing.

Aim: The objective of this study was to elucidate the healing

process involved in the incorporation of the biomaterials with

different biodegradation patterns following grafting of the fresh

extraction socket.

Methods: Third premolars in four quadrants of eight beagle

dogs were extracted and randomly treated with either one of

hydroxyapatite (HA), biphasic calcium phosphate (BCP),

b-tricalcium phosphate (b-TCP) or no graft (C). Histologic

observations and histomorphometric analysis at three zones(apical, middle and coronal) of the socket were done. Socket

area (S) and the proportions of newly formed bone (% NB),

residual biomaterials (% RB) and provisional matrix/marrow

space (% PCT) at 2, 4 and 8 weeks were measured. The num-

bers of osteoclast-like multinucleated cells (No.OC) were also

counted for three different zones.

Results: % NB was higher in control group compared to the

grafted groups for all healing periods.%NB of HA and BCP

increased with time periods, but the% RB showed different pat-

terns that decrease in BCP occurred while rare change in HA.%

NB of b-TCP showed smallest portion compared to other grafted

groups at 2 and 4 weeks, however increased in excess at8 weeks.% RB of b-TCP was less than HA and BCP for all heal-

ing periods. Numbers of multinucleated cells were higher in

BCP and b-TCP followed by HA and smallest in control group.

Conclusions and clinical implications: Within the limit of this

study, grafted biomaterials delayed bone formation of the

extraction socket, and different healing process was driven

according to the biodegradation patterns of biomaterials.

These histologic results can provide the evidence for the selec-

tion of biomaterials in socket preservation and immediate

implantation.


Socket grafting using b-tricalcium phosphate in ahydroxyl sulphate matrix

Minas Leventis,1 Orestis Vasiliadis,1 Nadia Theologie-lygidakis,1 Peter Fairbairn,2 Ioannis Iatrou1

1Department of Oral and Maxillofacial Surgery, Dental School,

University of Athens, Athens, Greece, 2Private Practice, London,

United Kingdom

Background: Studies in humans and animals have shown that

following tooth extraction, the alveolar bone becomes mark-

edly reduced as a result of resorption of the edentulous ridge.

This can negatively influence bone volume that is needed for

future implant placement. It is suggested that the ridge dimen-

sions can be preserved by socket grafting at the time of tooth

extraction with the use of various bone graft substitutes.

Aim: To evaluate the clinical efficacy of a biphasic synthetic

bone grafting material consisting of b-tricalcium phosphate in

a hydroxyl sulphate matrix for socket preservation and

implant integration at the post-extraction site.

Methods: In 4 of a series of 10 patients, requiring extraction of

a posterior tooth of the mandible or the maxilla, b-tricalcium

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phosphate in a hydroxyl sulphate matrix (Fortoss® VITAL, Bio-

composites®, Etruria, Stoke-on-Trent, England) was utilized as

a grafting material for socket preservation using the “Bio-Col”

technique. The horizontal ridge dimensions were measured

after tooth extraction and at implant placement after

3 months. Bone core biopsies were obtained prior to implant

placement for histologic, histomorphometric and microcom-

puted tomography analysis. Primary implant stability was

evaluated by resonance frequency analysis (Osstell ISQTM,Göteborg, Sweden).

Results: Analysis of the data showed that b-tricalcium phos-

phate in a hydroxyl sulphate matrix preserved adequately the

width of the alveolar ridge 3 months after tooth extraction.

Histologic, histomorphometric and microcomputed tomogra-

phy analysisrevealed pronounced bone regeneration and reso-

nance frequency analysis showed high ISQ levels at implant

placement.

Conclusions and clinical implications: The preliminary results

of this clinical study showed that b-tricalcium phosphate in a

hydroxyl sulphate matrix can be used successfully as a graft-

ing material for socket preservation prior to implant place-ment. The completion of all cases with detailed evaluation of

all results, the statistical analysis of the data and the compari-

son with other grafting materials will complete this prospec-

tive study in the near future.


Ridge preservation and augmentation using bonegraft substitutes: case series

Minas Leventis, Orestis Vasiliadis, Nadia Theologie-lygidakis, Ioannis IatrouDepartment of Oral and Maxillofacial Surgery, Dental School,

University of Athens, Athens, Greece

Background: Many studies have shown that preservation and

augmentation of the alveolar socket at the time of tooth

extraction is the most predictable way to preserve the dimen-

sions of the residual ridge. The materials and surgical tech-

niques in use today facilitate bone preservation and

augmentation prior to implant placement and enable clini-

cians to more predictably ensure the functional and esthetic

outcomes of the implants and subsequent restorations that are

delivered.

Aim: To evaluate clinically and radiologically the efficacy of

various bone graft substitutes in preserving and augmenting

post-extraction sites using minimally invasive surgical tech-

niques.

Methods: In adult patients requiring tooth extraction due to

trauma, periodontal disease or failed endodontic therapy

allografts (maxgraft®, botissdental GmbH, Berlin, Germany),

alloplasts (maxresorb® and maxresorb® inject, botissdental

GmbH, Berlin, Germany) or xenografts (cerabone®, botissden-

tal GmbH, Berlin, Germany) were used alone or in combina-

tion with wound dressing materials (Jason® collagen fleece,

botissdental GmbH, Berlin, Germany) or resorbable mem-

branes (Jason® m

Tissue Augmentation 2012

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