by David S. Hornbrook, DDS · 2012. 1. 12. · Chairman, Department of Restorative Dentistry Indiana University School of Dentistry Indianapolis, Indiana Jeff J. Brucia, DDS Lee Culp,

In This Issue:

A Clinical Technique for Placement of an Indirect Microhybrid Composite Inlayby David S. Hornbrook, DDS

in Dentistry

February 2002Vol. 1, No. 1

Achieving Clinical andFunctional Success When Fabricating a

Microhybrid Composite Inlayby David Grin, CDT

©2002. Medical World Business Press, Inc./An MWC Publication

Sponsored by 3M ESPEA Supplement to Contemporary Esthetics and Restorative Practice®

SynergyThe alliance between the dentist and lab technician

Premiere Issue

Dear Reader:

3M ESPE and Dental Learning Systems are pleased to presentthe first issue of a new clinical series, Synergy in Dentistry, for thedental professional and laboratory technician. This publication willoffer 2 hours of continuing education in 3 issues—February, June,and September 2002. The goal of this series is to foster and strength-en the alliance between the dentist and the laboratory, enabling bet-ter communication and clinical results.

Resin materials have been used in indirect restorative dental pro-cedures for the last 50 years. Early formulations were used in conjunc-tion with metal substrates because of their inadequate physical andmechanical properties. Their clinical shortcomings included poor wearresistance, marginal discoloration, and bulk discolorations. After theintroduction of filled composite resin materials, additional attemptswere made in the late 1970s to mid 1980s with laboratory-fabricatedrestorations. Once again, inadequate physical and mechanical proper-ties resulted in premature failures such as composite fractures whenstressed and discolorations at marginal areas.1,2

Significant progress appears to have been made in recent yearswith newly formulated composite resins for indirect applications.Specifically, applications involving inlays and onlays have shown themost promising clinical behavior in posterior teeth.3 The introductionof SinfonyTM indirect lab composite (3M ESPE) is representative ofrecent technology that uses a category of composite resins referred toas the “microhybrid composites” for indirect restorative applications.The following articles by Dr. Hornbrook and Mr. Grin provide a com-prehensive review of the evolution of this innovation in an indirectmicrohybrid composite. Their specific clinical applications are focusedon examples in posterior inlay restorations. Both authors provide thor-ough details on how to achieve optimum results when using SinfonyTM

in the identified clinical applications. While the long-term behavior ofthis class of restorative is presently unknown, very favorable laborato-ry data and limited clinical results suggest that a promising technologymay have finally arrived for the clinician focused on achieving opti-mum esthetics in restorative procedures.

Sincerely,E. Steven Duke, DDS Chairman, Department of Restorative DentistryIndiana University School of DentistryIndianapolis, Indiana

Jeff J. Brucia, DDS E. Steven Duke, DDSLee Culp, CDT

February 2002ADVISORY BOARD

This clinical series is sponsored by

Dental Learning Systemsis an ADA CERP Recognized Provider

Academy of General DentistryApproved National Sponsor

FAGD/MAGD Credit7/18/1990 to 12/31/2002

Publisher and President, Daniel W. Perkins; Director of Publishing Operations, Ken Senerth; Vice President of Sales and Associate Publisher, Anthony Angelini; EditorialDirector, Allison W. Walker; Associate Projects Editor, Lisa M. Neuman; Projects Director, Eileen R. Henry; Copy Editors, Barbara Marino and Susan Costello; Design Director,Special Projects, Liz Arendt; Circulation Director, Jackie Hubler; Northeast Regional Sales Manager, Jeffery E. Gordon; West Coast Regional Sales Manager, Michael Gee;Executive and Advertising Offices, Dental Learning Systems, 241 Forsgate Drive, Jamesburg, NJ 08831-1676, Phone (732) 656-1143, Fax (732) 656-1148.

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Contemporary Esthetics and Restorative Practice® (ISSN 1523-2581, USPS 017-212) is published 12 times a year by Dental Learning Systems, 241 Forsgate Drive, Jamesburg,NJ 08831-0505. Copyright © 2002. Medical World Business Press, Inc./A division of Medical World Communications, Inc. Printed in the USA. All rights reserved. No part of thisissue may be reproduced in any form without written permission from the publisher.

Contemporary Esthetics and Restorative Practice® is a registered trademark of Medical World Business Press, Inc. Medical World Communications Corporate Officers:Chairman/CEO, John J. Hennessy; President, Curtis Pickelle; Chief Financial Officer, Steven J. Resnick; Vice President of Business Development, Robert Issler; Vice President ofManufacturing, Frank A. Lake.Printed in the U.S.A.D476

David Grin, CDT Edward A.McLaren, DDS

David S.Hornbrook, DDS

Moshe Mizrachi,CDT

Bruce Small, DDS

Matt Roberts

in Dentistry

SynergyThe alliance between the dentist and lab technician

1. Um CM, Ruyter IE: Staining of resin-based veneering materials with coffee and tea.Quintessence Int 22:377-386, 1991.

2. O’Neal SJ, Leinfelder KF, Barrett CE: Clinical evaluation of Dentacolor as a posteriorveneering agent. J Esthet Dent 1:29-33, 1989.

3. Shellard E, Duke ES: Indirect composite resin materials for posterior applications.Compend Contin Educ Dent 20:1166-1171, 1999.

www.3MESPE.com

WARNING: Reading an article in Synergy in Dentistry does not necessarily qualify you to integrate new techniques or procedures into your practice. Dental Learning Systems expects itsreaders to rely on their judgment regarding their clinical expertise and recommends further education when necessary before trying to implement any new procedure.The views and opinions expressed in the article appearing in this publication are those of the author(s) and do not necessarily reflect the views or opinions of the editors, the editorial board,or the publisher. As a matter of policy, the editors, the editorial board, the publisher, and the university affiliate do not endorse any products, medical techniques, or diagnoses, and publica-tion of any material in this journal should not be construed as such an endorsement.

Michael Morgan,DDS

3SYNERGY IN DENTISTRY VOL. 1, NO. 1, 2002

Learning ObjectivesAfter reading this article, the reader should be able to:• discuss the rationale for using an indirect resin restoration.• describe the basic preparation, impressioning, and shade

determination of the resin restoration.• explain the bonding procedures using a new, dual-cured,

resin cement with a single component adhesive.

Dentists have long sought an indirect material suitablefor a variety of restorative indications, including full-coverage crowns and bridges, veneers, and inlays/

onlays. Porcelains and ceramics have predictably served thedental profession for more than 200 years, but have also pre-sented a number of clinically undesirable characteristics,including harsh wear of opposing teeth.1 Manufacturers haveresponded with a variety of indirect composite resin materialssuitable for anterior and posterior restorations.

This class of restorative material has evolved greatly since3M ESPE introduced one of the first BIS-GMA composites in1964. Indirect laboratory composites may provide many attrac-tive attributes for restorative procedures, including kindness toopposing dentition, ease of use, esthetics, placement with adhe-sive techniques, conservative preparation requirements, andresilience.2 However, despite improvements in filler, couplingagents, and polymers, resistance to wear has been a concernthat has limited more widespread use of this material.3,4

Therefore, major efforts have been made to enhance themechanical and physical characteristics of indirect compositesto better mimic porcelain for specific clinical applications.1

These include the addition of new resins, fiber reinforcement,and photopolymerization techniques.1 As a result, today’s indi-rect composites (including Sinfony™,a indirect lab composite,belleGlass™ HPb, Targis Vectris™,c, and Artglass®,d) demonstratesuperior mechanical properties, wear, and clinical performance,

and enable dentists to provide patients with functional andesthetic restorations. While these innovations cannot addressevery restorative challenge, enhancements to indirect resinalternatives enable dentists to use conservative preparationdesigns and varying surface treatments to achieve functionaland esthetic results.

Material CharacteristicsThe indirect material used in this case is Sinfony™, an ultra-

fine particle microhybrid composite designed for laboratories tobuild and layer in a manner similar to porcelain. Indicated forinlays/onlays, veneers, and full-coverage crown restorations,this material demonstrates exceptional flexibility, impactstrength, and color stability, as well as lifelike esthetics andtranslucency. In addition to superior wear resistance, Sinfony™ iseasy to finish and polish, and is plaque and stain resistant.

The physical properties of Sinfony™ include enhancedstrength compared to earlier generations of indirect laboratorycomposites.5 Sinfony™ indirect laboratory composite measuredhigher in flexural strength—105 MPa—compared to threeother materials.6 Because Sinfony™ has a lower flexural mod-ulus, the material is less brittle, making it ideal for veneeringover flexible understructures, such as fiber bridge substrates ortelescope crowns.6 Further, in transverse impact tests conduct-ed internally by 3M ESPE, Sinfony™ demonstrated an impactstrength of 7.5 mJ/mm, surpassing other materials that are rel-atively brittle and unable to satisfy the demands of modernveneering materials.2 Additionally, the material’s compressivestrength of 275 MPa represents significant advantages over 2out of 3 alternate indirect composites.6

In solubility tests, which are associated with waterrepellency of the polymer matrix, Sinfony™ demonstrated asignificantly low solubility of 19 µg/mm (60 days).3,7 Inboth a mastication-simulator machine and a three-media-wear machine, Sinfony™ showed significantly less abrasionthan other materials at 175 µm,8 exhibiting low-wear characteristics.

The processing and layering technique used in fabricat-ing Sinfony™ restorations ensures the enhanced physicalproperties noted, in addition to a natural vitality and opales-

A Clinical Technique for Placement of an IndirectMicrohybrid Composite Inlay

ABSTRACTFor years, dentists have sought a durable indirect

restorative alternative to porcelains and ceramics thatwould demonstrate clinical and material characteristicssuitable for a variety of functional and esthetic indica-tions. With major enhancements to the mechanical andphysical characteristics of composite materials hascome the introduction of indirect alternatives that enabledentists to place conservative, durable, and estheticrestorations. This article discusses the historic short-comings of earlier generations of indirect composites,details the clinical benefits of a new-generation, indirectmicrohybrid composite (Sinfony™, 3M ESPE), and pre-sents a clinical technique for placing a mesio-occlusalinlay fabricated with this material.

David S. Hornbrook, DDSDirector, P.A.C.~LivePrivate Practice La Mesa, California

a 3M ESPE, St. Paul, MN 55144; (800) 634-2249; b KerrLab, Orange, CA 92867; (800)

322-6666; c Ivoclar Vivadent®, Amherst, NY 14228; (800) 533-6825; d J.F. Jelenko &Co, Armonk, NY 10504; (800) 431-1785

cent and fluorescent effects.9 The mate-rial is easily matched to surroundingteeth by building up Vita®,c shades in amanner similar to porcelain—flowingonto the surface without entrapping bub-bles. Sinfony™ restorations can be seatedusing enamel/dentin adhesive bondingor traditional cementation techniqueswhen placed with a metal substructure.

When used in combination withadhesive materials specifically designedfor use with indirect procedures, such as3M ESPE Single Bonda and 3M ESPERelyX™ ARCa, Sinfony™ produces ex-ceptional bond strengths.10,11 3M ESPERelyX™ ARC bonds indirect restorationssecurely, yet demonstrates easy handlingand cleanup characteristics without com-promising its adhesive or physical prop-erties.12 Further, 3M ESPE Single Bond

has been repeatedly shown to produceexceptional shear bond strengths whenapplied to enamel (>30 MPa) and dentin(>22 MPa).13

Case PresentationA 42-year-old man presented with

a failing mesio-occlusal compositerestoration on tooth No. 18 (Figure 1).To maintain the conservative andesthetic nature of his previous dentalwork, planned treatment involvedreplacing the defective restoration witha microhybrid, indirect, mesio-occlusalinlay using Sinfony™.

Clinical TechniquePreparation

The preexisting composite restora-tion was removed using a tapered, flat-

ended diamond (Axis 845KRe) (Figure2), maintaining as much healthy toothstructure as possible. All internal lineangles were rounded, a 5- to 7-degreetaper of preparation walls was es-tablished, and undercuts were removed.A butt-joint margin was placed at theproximal gingival margin. All marginswere smoothed using a 30-µm finishingdiamond to eliminate any roughness.

Impression MakingImpressions were made using a

polyvinyl siloxane (PVS) impressionmaterial in a full-arch tray. The tech-nique used a wash material placedaround the preparation and on the sur-rounding occlusal surface. The tray

4 VOL. 1, NO. 1, 2002 SYNERGY IN DENTISTRY

Figure 1—Preoperative mesio-occlusalcomposite restoration with recurrent decayon tooth No. 18.

Figure 2—Composite is removed, andpreparation is defined with an 845KR dia-mond. All internal line angles are rounded.

Figure 3—The provisional restoration isremoved and a rubber dam is placed.

Figure 4—The preparation is cleaned usingan antibacterial solution before etching.

Figure 5—The restoration is tried in toensure adequate marginal adaptation.

Figure 6—Enamel, followed by dentin, isetched with 35% phosphoric acid for 15seconds.

Figure 7—Dentin is etched with 35% phos-phoric acid for 15 seconds.

Figure 8—After rinsing, the preparation isblotted dry to achieve the most ideal surfacefor adhesive.

Figure 9—A single-component adhesiveagent is applied to the preparation for 20 seconds.

e Axis Dental Corporation, Irving, TX 75038; (800) 355-5063

5SYNERGY IN DENTISTRY VOL. 1, NO. 1, 2002

was loaded with a rigid heavy-bodymaterial at the same time the wash wasplaced around the preparation andinserted into the mouth. Accuratereproduction and detail is imperative toachieve a well-fitting restoration. Arigid PVS bite registration materialwas used to capture the bite relation-ship. An opposing impression wasmade using a medium-body PVSimpression material, and a facebow(Stratos 200®,f) was taken.

Shade SelectionThe shade was chosen by identify-

ing dentin and enamel shades separately.Using the Vita® shade guidec, a dentinshade was chosen by matching the gin-gival third of the buccal surface of theadjacent tooth. The enamel shade wastaken from the remaining occlusalenamel on the prepared tooth. Occlusalstain was noted and identified for theceramist by photographing a nonre-stored tooth on the opposing arch. It wasalso requested that the restoration bevery translucent at all margins to facili-tate blending into the surrounding toothstructure.

ProvisionalizationProvisionalization was achieved

using a BIS-Acryl provisional material(3M ESPE Protemp™ Garanta). A preop-erative impression was made using ahalf-arch triple tray loaded with a medi-um-body, fast-setting PVS impressionmaterial. After preparation and masterimpressions, the preoperative impressionwas loaded with the BIS-Acryl materialand seated back in the mouth for 2 min-utes. After 2 minutes, the impression was

removed and the BIS-Acryl provisionalwas teased out of the impression,trimmed, and placed back into the prepa-ration. After a total of 4 minutes, the pro-visional was removed, trimmed using analuminum oxide disc (3M ESPE Sof-Lex™ R Discsa) and 16-fluted carbideburse, and tried back in the mouth.Occlusal equilibration of the provisionalwas accomplished using a 16-fluted foot-ball-shaped carbide bure. The provisionalwas cemented using a resin-based, dual-cured provisional cement (Provilink®,c),and polished with composite finishingpoints and cups (Astropol®,c).

Placement of the FinalRestoration

The provisional restoration wasremoved using a sharp scaler placedunder the proximal height of contour.Because a resin-based provisionalcement was used, there was minimalcement to clean from the preparation. Arubber dam was placed to isolate thepreparation (Figure 3). The preparationwas cleaned using a chlorhexadine solu-tion in a syringe with a brush tipf (Figure4). The restoration was then seated intothe preparation to ensure complete seat-ing and marginal adaptation, and theproximal contact was checked (Figure5). The restoration was removed andcleaned with 35% phosphoric acid toremove any contaminants and to createan acidic surface, and then rinsed anddried.14 A silane coupling agent (3MESPE RelyX™ Ceramic Primera) wasapplied to the internal surface of theinlay and allowed to sit undisturbed for 1minute. This was then air-dried withmoisture-free air, and a single-compo-nent adhesive agent, 3M ESPE SingleBond, was thinly applied to this surface.

The inlay was then placed in a light pro-tective container (Vivapadc).

The enamel and dentin surfaceswere etched for 15 seconds with 35%phosphoric acid and rinsed for 5 seconds(Figures 6 and 7).15 A polyester-tuftedbrush was used to remove excess mois-ture from the tooth surface without des-iccation (Figure 8).16 3M ESPE SingleBond was applied to the enamel anddentin in multiple coats for 20 seconds(Figure 9). A source of moisture- and oil-free air was used to evaporate any excessalcohol solvent for 15 seconds. Theadhesive agent was then polymerizedwith a halogen light for 10 seconds.17 3MESPE RelyX™ ARC was mixed andplaced into the preparation (Figure 10).This cement was chosen because itestablishes a preliminary chemical poly-merization to a gel-like consistency thatfacilitates easy cleanup and removal ofexcess cement.10-12 A warm shade (A3)was chosen to help establish achameleonlike result.

The inlay was seated in the prepa-ration with moderate pressure for 3 min-utes to ensure complete seating (Figure11). Moderate pressure was appliedwith a blunt-tipped instrument through-out the 3 minutes. Then, an explorer wasused to carefully peel away the excesscement from the margins (Figure 12).Floss was used to remove excess inter-proximal cement.

An oxygen inhibitor (DeOx®,f) wasplaced on all margins to eliminate theformation of an oxygen inhibition layer(Figure 13). The restoration was thenpolymerized using a halogen light for90 seconds to ensure complete poly-merization of the resin cement. Theoxygen inhibition medium was rinsed,and any excess cement was removed

f Ultradent Products, Inc, South Jordan, UT 84095;(800) 552-5512

Figure 10—The dual-cure resin cement isapplied to the preparation.

Figure 11—The definitive restoration isseated into the preparation and held inplace for 3 minutes.

Figure 12—After 3 minutes, excess cementis easily removed from the cavosurfacemargins using a scaler or explorer.

using a scaler and scalpel blades (BardParker 12Bg) (Figure 14). Rough mar-gins were smoothed using a 15-µmfinishing diamond. The interproximalgingival margin was finished using athin aluminum oxide strip (3M ESPESof-Lex™ Stripa) (Figure 15). Theocclusal surface was adjusted usingfinishing diamondse, and the final pol-ish was established with a compositefinishing system (Astropol®) (Figures16 through 18).

ConclusionIndirect, metal-free composite

restorations such as Sinfony™ may pro-vide viable options for conservativerestorative procedures. Additionally,enhanced physical properties increasewear and stain resistance compared toearlier generations of indirect compos-ite restorative materials.

For clinicians seeking an indirectcomposite material for a variety ofindications, Sinfony™ offers highplaque resistance, superior esthetics,low water absorption, and a low modu-lus of elasticity. Further, the materialprovides excellent polishability and

long-term durability.Disclosure/Acknowledgment

Dr. Hornbrook is a consultant to 3MESPE. He would like to thank DavidGrin, CDT, at Lone Mountain DentalStudio, St. George, Utah.

References1. Shellard E, Duke ES: Indirect composite

resin materials for posterior applications.Compend Contin Educ Dent 20(12):1166-1171, 1999.

2. Chalifoux PR: Treatment considerationsfor posterior laboratory-fabricated com-posite resin restorations. Pract PeriodontAesthet Dent 10(8):969-980, 1998.

3. Burke FJ, Watts DC, Wilson NH, et al.Current status and rationale for compositeinlays and onlays. Br Dent J 170(7):269-273, 1991.

4. Leinfelder KF: Ask the expert. Will ceram-ic restorations be challenged in the future?J Am Dent Assoc 132(l):46-47, 2001.

5. Terry DA, Touati B: Clinical considera-tions for aesthetic laboratory-fabricatedinlay/onlay restorations: a review. PractProced Aesthet Dent 13(1):51-60, 2001.

6. Trajtenberg C, Eldiwany O, Li D, et al:Properties of advanced laboratory compos-ites [abstract]. J Dent Res 78 (specialissue):157, 1999. Abstract 413.

7. Riebeling A, Buhlman I, Schinker A, et al:Resin-metal bond: new resins and bondingsystems using silanization [abstract]. J DentRes 78 (special issue):222, 1999. Abstract929.

8. Hoffman E, Rosentritt M, Behr M, et al:Abrasion of indirect composite restora-

tions after artificial abrasion in the masti-cation simulation in a three-media-wearmachine [abstract]. Deutsche Gesellschaftfür zahnärztliche Prothetik undWerkstoffkunde. 2000. Abstract 11.

9. Grin D: Creating esthetic composite restora-tions. J Dent Technol 17(4):13-16, 2000.

10. Frauenholz T, Rosentritt M, Behr M, et al.Determination of shear bond strength ofcomposites on fiber-reinforced FPD mate-rial [abstract]. J Dent Res 77 (specialissue), 1998. Abstract 1486.

11. Alkumru HN, Ozcan M, Negriz I, et al:Effect of surface treatment on the bondstrength of luting cement to In-Ceram[abstract]. J Dent Res 77 (special issue),1998. Abstract 2238.

12. Ario PD: Immediate shear bond strengthsof a new 3M resin cement. J Dent Res 77(special issue), 1998. Abstract 2506.

13. Ario PD: Shear bond strengths of a new3M dental adhesive. J Dent Res 76 (specialissue), 1997. Abstract 1381.

14. van Dijken JW, Olofsson AL, Holm C: Fiveyear evaluation of class III composite resinrestorations in cavities pre-treated with anoxalic- or phosphoric acid conditioner. JOral Rehabil 26(5):364-371, 1999.

15. Pioch T, Staehle HJ, Duschner H, et al:Nanoleakage at the composite-dentin inter-face: a review. Am J Dent 14(4):252-258,2001.

16. DeGoes MF, Pachane GC, Garcia-GodoyF: Resin bond strength with differentmethods to remove excess water fromdentin. Am J Dent 10(6):298-301, 1997.

17. Tulunoglu O, Uctash M, Alacam A, et al: Microleakage of light-cured resin andresin-modified glass-ionomer dentin bond-ing agents applied with co-cure vs pre-cure

6 VOL. 1, NO. 1, 2002 SYNERGY IN DENTISTRY

Figure 13—After the excess cement isremoved, an oxygen-inhibition solution isplaced on all margins.

Figure 14—After polymerization, the restora-tion is rinsed, and any excess resin cement isremoved with a scaler or scalpel blade.

Figure 15—The interproximal gingivalmargin is finished using a thin aluminumoxide strip.

Figure 16—All margins are finished usingcomposite finishing diamonds, and occlu-sion is evaluated and adjusted.

Figure 17—The restoration is polishedusing composite finishing instruments.

Figure 18—The final restoration demon-strates excellent marginal integrity, surfacesmoothness, anatomical reproduction, andesthetics.

g Becton Dickinson and Company, Franklin Lakes, NJ07417; (888) 237-2762

7SYNERGY IN DENTISTRY VOL. 1, NO. 1, 2002

Learning ObjectivesAfter reading this article, the reader should be able to:• discuss how to properly color map a tooth.• describe how to properly evaluate tooth shade.• list the instruments needed and the steps involved in fab-

ricating microhybrid restorations.

Indirect composite resins have been used in dentistry formany years, and they continue to evolve and improve. Thisauthor has had the opportunity to work with most of them

over the past 12 years. Some of these materials have performedbetter than others. One material that appears to be heading forthe top rung of the evolutionary ladder is 3M ESPE Sinfony™,a

indirect lab composite. Its unique physical makeup and han-dling characteristics are intriguing. Other materials in this cate-gory include belleGlass™ HPb, Targis Vectris™,c, and Artglass®,d.

IndicationsSinfony™ is an indirect composite resin material used in

creating conservative inlays and onlays. While the materialcan be used for other applications, this article will be limitedto the inlay/onlay application.

Color MappingColor mapping is a technique used to accurately describe

tooth color and characteristics. Matching remaining toothstructure when designing and fabricating indirect compositeresin restorations is dependent on proper tooth preparation,shade evaluation, shade communication, and restoration fab-rication. These aspects need to be carefully coordinatedbetween the clinician and technician.1 Tooth preparation thatcoordinates function and form will be discussed later. Shadeevaluation is one of the most important, overlooked, andmisunderstood areas related to indirect composite resinrestorations. The evaluation procedure can be simplified andexpedited using the following procedure.

Shade EvaluationThe shade should be taken before the teeth have dehy-

drated or have been prepared.2 The shade of the buccal sur-faces of the teeth should be evaluated. Many clinicians, intheir haste to begin the preparation procedure, overlook thecritical nature of when to evaluate shade. First, the value ofthe remaining dentition should be determined. Value isdefined as the amount of reflection present; thus, a highlyreflective dentition would appear bright or high-value. A darkor dingy dentition is low-value. This evaluation should takeno more than a few seconds. If the clinician is unable todetermine the value, then it is described as medium. Manyevaluators confuse value with chroma, or amount of color.

The value should be determined before ever picking upa shade guide. Turn the operatory light off during this and thenext two steps. Now, the hue (color) is determined. Teethtend to fall into five basic hues: white, yellow, orange, gray,and brown. Again, before ever handling the shade guide, thehue should be chosen. Most teeth fall into the yellow colorfamily. After the hue has been selected, the amount ofcolor—chroma—can be determined. Note that the shadeguide can be used and the tabs compared only with that par-ticular color family to avoid confusion. The shade tab thatmost closely represents the chroma should be selected. If asituation arises where the question of color saturation is dif-ficult, err toward more chroma. A restoration with more chro-ma blends more naturally with remaining dentition. After thevalue, hue, and chroma have been determined, the operatorylight can be turned back on. The remaining steps refine theevaluation process. These areas should be evaluated byexamining the occlusal surfaces of the teeth.

The occlusal fossae of the dentition are examined next.A hue will often emanate through this area. This is the dentinpeeking through the thinner areas of enamel. Often, this areawill appear yellow–orange. If all of the remaining dentitionhas been restored, the clinician can approximate the occlusalfossae halo color by referring to the hue family discussedpreviously.

After examining the occlusal fossae of the dentition, theamount of pit-and-fissure characterization is determined. Lightwould be found in the pits only. Medium is described as stainbeing present in the pits as well as in the developmental anato-my. Dark would describe the pits, developmental anatomy, andsome—but not all—of the supplemental anatomy. This descrip-

Achieving Clinical and Functional Success WhenFabricating a Microhybrid Composite Inlay

ABSTRACTIndirect composite resins have been used in den-

tistry for many years, and they continue to evolve andimprove. When prescribed appropriately and fabricatedproperly, indirect composite resin restorations become asuccessful treatment option in modern dentistry. Thisarticle details the tasks involved in fabricating a micro-hybrid composite inlay with Sinfony™ (3M ESPE) andprovides recommendations to ensure clinical, functional,and esthetic success.

David Grin, CDTLone Mountain Dental StudioSt. George, Utah

a 3M ESPE, St. Paul, MN 55144; (800) 634-2249; b KerrLab, Orange, CA 92867;

(800) 322-666; c Ivoclar Vivadent®, Amherst, NY 14228; (800) 533-6825; d J.F.Jelenko & Co, Armonk, NY 10504; (800) 431-1785

8 VOL. 1, NO. 1, 2002 SYNERGY IN DENTISTRY

tion must be shared with the technicianto eliminate ambiguity. Finally, theamount of hypocalcified surface is deter-mined. Again, light, medium, and darkdesignations will suffice. A word of cau-tion: If the shades were evaluated whenthe teeth were dehydrated, the amount ofhypocalcification would appear falselyheavy. With a little practice, this entireprocedure can be performed in less than60 seconds.

Tooth PreparationTooth preparation for a Sinfony™

restoration is the same as with othercomposite or all-porcelain inlay/onlays. Overall, 1.5 mm to 2 mm ofreduction is required. A 1-mm to 1.5-mm width at the shoulder margin is

mandatory. All sharp line angles shouldbe eliminated to reduce stresses.3,4

Inlays should have 15 degrees ofdivergence, and gross undercuts shouldbe eliminated. An esthetic margin zonecan be created at the buccal surface ifthat cusp has been hooded by extend-ing a slight chamfer down off theshoulder. Whenever possible, the cer-vical margin should remain supragingi-val to facilitate bonding.

ImpressionA quality polyvinyl siloxane

impression is required for accurate fab-rication. The impression should beaccurate and free from voids and dis-tortion. Margins should be clear anddefinable. Tray adhesive must be used.

The laboratory technician will pour theimpression several times during thefabrication process.5

Model and DieModels should be poured using a

neutral-colored quality die stone follow-ing the manufacturer’s instructions.Colored die stones inhibit the techni-cian’s ability to properly formulateshades because the underlying hue ofthe stone combines with the dentin andalters the perception of color. Theremovable die should be sealed using asuperthin cyanoacrylate glue (Figure 1).Clear blockout material should be usedfor the die undercuts (Figures 2 and 3).Models are mounted, equilibrated, andready for restoration fabrication.

Figure 1—The removable is sealed usingsuperthin cyanoacrylate glue.

Figure 2—Clear blockout material is usedfor the die undercuts.

Figure 3—Clear blockout material is beingplaced on the undercuts of the die.

Figure 4—The separator is applied to themaster die to facilitate release and allowedto dry.

Figure 5—The appropriate dentin materialis applied to the floor and interproximalareas of the die using the PTC #4 instrument.

Figure 6—Orange modifier is applied tothe occlusal fossae area.

Figure 7—The translucent material (T1) isapplied to the axial walls up to the cavo-surface margins and kept 0.5 mm out ofocclusal contact.

Figure 8—The E3 enamel material isapplied and a fishmouth border is created.

Figure 9—The buildup is still 0.5 mm out ofocclusal contact.

9SYNERGY IN DENTISTRY VOL. 1, NO. 1, 2002

InstrumentationThe author prefers to limit instru-

mentation to as few instruments aspossible. The following instrumentsare recommended: (1) PTC #4 waxinginstrumente for adding compositematerial; (2) 0.008-inch endodonticfile (K-filef) for placing pit stain; and(3) a small brush for characterizing.Excessive instrumentation slows theprocess and is simply not necessary tocreate beautiful restorations.2

Creating the RestorationThe separator is applied to the

master die to facilitate release (Figure4) and allowed to dry. The prescription

from the dentist is carefully reviewed.The appropriate dentin material isapplied to the floor and interproximalareas of the die using the PTC #4instrument (Figure 5). This material isprecured for 10 seconds. Next, anorange modifier is applied to theocclusal fossae area (Figure 6). Thisapplication is precured for 10 seconds.When that layer is cured, the translu-cent material (Sinfony™ T1) is appliedto the axial walls up to the cavosurfacemargins. In addition, a thin bead line isrun across the marginal ridge areas,and the onlay cusp areas are augment-ed. This application should be kept 0.5mm out of occlusal contact (Figure 7)and precured for 10 seconds. Theenamel material (in this case Sinfony™

E3) is applied directly over the materi-

al previously applied and a fishmouthborder is created (Figure 8). Thebuildup should still be 0.5 mm out ofocclusal contact (Figure 9). Next, theocclusal convexities can be added andprecured incrementally and one at atime to maintain separation/delineation(Figures 10 and 11).

FinishingBefore final curing, the restoration

is rough-finished. The occlusal interfer-ences are checked first (Figure 12).Premature contacts are eliminated usinga high-speed 1D diamond burc and thenthe anatomy is defined using a high-speed mosquito burg (Figure 13). Theanatomy is softened and accentuatedusing the 1D diamond bur (Figure 14).The anatomy can be further detailed

Figure 10—The occlusal convexities areadded and precured incrementally to main-tain separation/delineation.

Figure 11—The occlusal convexities areadded and precured incrementally to main-tain separation/delineation.

Figure 12—Occlusal interferences arechecked.

Figure 13—The anatomy is defined using ahigh-speed mosquito bur.

Figure 14—The anatomy is further softenedand accentuated using a 1D diamond bur.

Figure 15—The anatomy is further detailedusing a low-speed, round-end, diamond bur.

Figure 16—A thin coat of Sinfony™ Activatorliquid is applied to reduce the surface tensionand facilitate characterization.

Figure 17—Brown modifier is applied to thefissures using the 0.008-inch endodontic file.

Figure 18—White modifiers are applied toaccentuate convexities.

e PTC/Blue Dolphin Products, Morgan Hill, CA 95037;

(800) 448-8855; fBrasseler USA, Savannah, GA 31419;(800) 841-4522

10 VOL. 1, NO. 1, 2002 SYNERGY IN DENTISTRY

using a low-speed, round-end, dia-mond burg (Figure 15). All remainingproximal and axial contours are adjust-ed with a silicone wheel. All surfacesare cleaned with a blast of compressedair, and a thin coat of Sinfony™

Activator liquida is applied (Note: donot precure). This will reduce the sur-face tension and facilitate characteriza-tion (Figure 16). Brown modifier isapplied to the fissures using the 0.008-inch endodontic file (Figure 17).Finally, white modifiers are applied toaccentuate convexities (Figure 18).The restoration is removed from thedie (Figure 19), and the margins areinspected for overextensions. Therestoration is placed in the curing unitand programmed according to the man-ufacturer’s instructions.

PolishingAfter the restoration has been

polymerized, it should be placed backon the die and rough-finished using a

Fuzzy Wheelh (Figure 20). Externalsurfaces are polished using DiashineFineh and a soft-bristle brush (Figure21). A shiny luster should appearalmost immediately. The restoration,as well as the die, should now besteam cleaned. The restoration isremoved using a piece of clear utilitywax. The restoration is steam cleanedagain, and the fit is checked again ona separate die to ensure accurate fitand marginal integrity (Figure 22).The restoration is then seated on asolid model to refine the path of inser-tion and proximal contact (Figure 23)and returned to the master die for finalverification. The internal aspects ofthe restoration are lightly air abradedusing Rocetec™,a.

ConclusionWhen prescribed appropriately

and fabricated properly, indirect com-posite resin restorations are a verysuccessful treatment option. By fol-

lowing sound protocol for color map-ping, preparation design, impressionmaking, and creation of models anddies, esthetic and functional indirectcomposite inlays can be successfullyand predictably fabricated.

DisclosureMr. Grin is a consultant to 3M

ESPE.

References1 . Derbabian K, Marzola R, Donovan TE, et

al: The science of communicating the art ofesthetic dentistry. Part III: precise shadecommunication. J Esthet Restor Dent13(3):154-162, 2001.

2. Grin D: Creating esthetic compositerestorations. J Dent Technol 17(4):13-16,2000.

3. Jackson RD: Indirect resin inlay and onlyrestorations: a comprehensive clinicaloverview. Pract Periodontics Aesthet Dent11(8):891-900, 1999.

4. Koczarski MJ: Utilization of ceromerinlays/onlays for replacement of amalgamrestorations. Pract Periodontics AesthetDent 10(4):405-412, 1998.

5. Craig RG, Johnson KT: Accuracy of mod-els for indirect posterior restorations. J Oral Rehabil 20(5):483-490, 1993.

Figure 19—The restoration is removedfrom the die.

Figure 20—The restoration is placed backon the die and rough-finished.

Figure 21—External surfaces are polished.A shiny luster appears almost immediately.

g Axis Dental Corp, Irving, TX 75038; (800) 355-5063

Figure 22—The fit of the restoration ischecked on a separate die to ensure accu-rate fit and marginal integrity.

Figure 23—The restoration is seated on asolid model to refine the path of insertionand proximal contact.

h VH Technologies, Bellevue, WA 98005; (888) 628-8300

11SYNERGY IN DENTISTRY VOL. 1, NO. 1, 2002

QuizThis supplement to Contemporary Esthetics and Restorative Practice® provides 2 hours of Continuing

Education credit from Dental Learning Systems. To receive credit, complete the enclosed answer sheet and mailit, along with a check for $20, to Dental Learning Systems, 405 Glenn Drive, Suite 4, Sterling, VA 20164-4432, for processing. You may also phone your answers in to (888) 596-4605, or fax them to (703) 404-1801.Participants with a score of at least 70% will receive a certificate documenting completion of the course. Formore information, call 800-926-7636, ext 180.

Program #: D476

This Supplement to Contemporary Esthetics and Restorative Practice® was made possible through an unrestricted educational grant from 3MESPE. To order additional copies, call 800-926-7636, x180. D476

1. In transverse impact tests,Sinfony™ demonstrated an impactstrength of:a. 0.75 mJ/mm.b. 7.5 mJ/mm.c. 75 mJ/mm.d. 750 mJ/mm.

2. In a three-media-wear machine,Sinfony™ showed significantly lessabrasion than other materials at:a. 1.75 µm.b. 17.5 µm.c. 175 µm.d. 1,750 µm.

3. How many degrees of taper wereestablished in the preparationwalls?a. 1 to 3b. 3 to 5c. 5 to 7d. 7 to 9

4. What type of margin was placed atthe proximal gingival margin?a. butt-jointb. chamferc. featherd. beveled

5. Provisionalization was achievedusing:a. a copper inlay.b. an aluminum inlay.c. a BIS-Acryl provisional material.d. a composite provisional material.

6. A silane coupling agent wasapplied to the internal surface ofthe inlay and allowed to sit undis-turbed for:a. 1 minute.b. 2 minutes.c. 5 minutes.d. 20 minutes.

7. Moisture- and oil-free air was usedto evaporate any excess:a. saliva.b. water.

c. alcohol solvent.d. BIS-GMA.

8. After how long was an explorerused to carefully peel away theexcess cement from the margins?a. 1 minuteb. 2 minutesc. 3 minutesd. 4 minutes

9. An oxygen inhibitor was placed onall margins to eliminate the forma-tion of:a. a bubble zone.b. an oxygen inhibition layer.c. cross-link polymerization.d. parallel polymerization.

10. Any rough margins were smoothedusing a:a. 15-µm finishing diamond.b. 30-µm finishing diamond.c. 15-µm finishing carbide.d. 30-µm finishing carbide.

11. Matching remaining tooth struc-ture when designing and fabricat-ing indirect composite restorationsis dependent on:a. proper tooth preparation.b. shade evaluation and communi-

cation.c. restoration fabrication.d. all of the above

12. What is defined as the amount ofreflection present?a. valueb. reflectivityc. hued. chroma

13. Teeth tend to fall into how manybasic hues?a. 4b. 5c. 6d. 7

14. Most teeth fall into which familyof color?a. whiteb. yellowc. oranged. gray

15. If a situation arises where thequestion of color saturation is dif-ficult, err toward more:a. hue.b. value.c. chroma.d. tint.

16. Dark would be used to describe:a. pits.b. developmental anatomy.c. some, but not all, of the

supplemental anatomy.d. all of the above

17. Colored die stones inhibit thetechnician’s ability to:a. use colored wax.b. use clear wax.c. properly formulate shades.d. see the margins.

18. For instrumentation, which of thefollowing instruments is recom-mended?a. a PTC #4 waxing instrumentb. an 0.008-inch endodontic filec. a small brushd. all of the above

19. What modifiers are applied toaccentuate convexities?a. whiteb. yellowc. oranged. gray

20. During polishing, the restorationis removed using a(an):a. explorer.b. piece of clear utility wax.c. spoon.d. floss.

CE 2 Mr. Grin

CE 1 Dr. Hornbrook