658 THE JOURNAL OF PROSTHETIC DENTISTRY VOLUME 86 NUMBER 6

The demonstrated high survival rate of dentalimplants has made the requirement for retrievabilityless significant. Cement retention for implant restora-tions is an acceptable alternative to screw retention.1The advantages of cement-retained restorationsinclude enhanced ability to develop esthetics andocclusion because of the absence of screw access holes,enhanced ability to achieve passive fit for frameworks,and reduced complexity of clinical and laboratory pro-cedures.1-3

The ITI implant (Straumann USA, Cambridge,Mass.) is a single-stage implant with a shoulderrestorative finish line oriented at an angle relative tothe implant body. The ITI solid abutment is used forcement-retained restorations with components avail-able that facilitate the impression-making procedure(Fig. 1). The ITI impression cap provides excellent tis-sue retraction,2 and the ITI positioning cylinder allowsaccurate positioning of the abutment analog in theimpression (Fig. 2). However, the configuration of theimplant shoulder makes direct intraoral fabrication of aprovisional restoration with conventional techniquesdifficult, especially when the shoulder location is sub-gingival. With the use of cement-retained implantrestorations, adequate cement removal with subgingi-val implant margins may be difficult, andinstrumentation may produce scratches and gouges onthe restoration and abutment.4

Provisional implant restorations should developand maintain desired soft tissue contours. The accu-racy of fit and marginal integrity of provisional

restorations affects gingival health.5 This articledescribes several methods for the direct intraoralfabrication of provisional restorations for the ITIsolid abutment.

TECHNIQUES

Burn-out coping technique

This technique requires the use of the ITI plastic(burn-out) coping (Fig. 3).1. Place mechanical retention on the plastic coping

Options for the fabrication of provisional restorations for ITI solidabutments

Herman B. Dumbrigue, DDM,a Josephine F. Esquivel, DDM, MS,b and Dincer C. Gurun, DMDc

Baylor College of Dentistry, Texas A & M University System Health Science Center, Dallas, Texas, andCollege of Dentistry, University of Florida, Gainesville, Fla.

In this article, 4 techniques for fabricating provisional restorations for ITI solid abutments aredescribed. The use of a burn-out coping, acrylic resin coping, impression cap, and protective capare presented, and the advantages and disadvantages of each are discussed. (J Prosthet Dent2001;86:658-61.)

aAssistant Professor and Assistant Director, Advanced Education inGeneral Dentistry, Baylor College of Dentistry.

bAssistant Professor, Department of Prosthodontics, University ofFlorida College of Dentistry.

cClinical Assistant Professor, Department of Prosthodontics,University of Florida College of Dentistry.

Fig. 1. Solid abutments replacing right maxillary sextant.

Fig. 2. Two-piece impression transfer system for solid abutment.

by creating horizontal cuts with a separatingdisk.

2. Wet the surface of the coping with monomer, andapply acrylic resin (SNAP; Parkell, Farmingdale,N.Y.) with the use of the bead brush technique6

to ensure that the resin engages the mechanicalretention created.

3. Reduce the height of the plastic coping to thelevel of the solid abutments, and seat the plasticcopings intraorally (Fig. 4).

4. Use a vacuum-formed matrix intraorally to pro-vide appropriate contours for the provisionalrestoration with acrylic resin (Fig. 5). The marginconfiguration of the provisional restoration isalready established in the plastic coping.

Resin coping technique

This technique requires the laboratory fabricationof an acrylic resin coping on a brass ITI practice solidabutment connected to an ITI practice implant. Thisassembly serves as a die for fabrication of the resin cop-ing.7 (A laboratory analog may be substituted for thebrass implant and abutment.)

1. Attach a brass ITI practice solid abutment to anITI practice implant, and hand tighten.

2. Lubricate the die assembly with petroleum jelly.3. Fabricate an acrylic resin coping on the die assem-

bly with the use of the bead brush technique.Remove any excess material with an acrylic bur,and verify that the margin is well adapted.

4. Seat the resin coping intraorally, and reduce it tothe level of the solid abutment.

DUMBRIGUE, ESQUIVEL, AND GURUN THE JOURNAL OF PROSTHETIC DENTISTRY

DECEMBER 2001 659

5. Use a vacuum-formed matrix intraorally to pro-vide appropriate contours for the provisionalrestoration with the use of acrylic resin (Fig. 5).

Impression cap technique

This method requires the use of an ITI impressioncap for solid abutments.

1. Place an ITI impression cap over the solid abutment.The impression cap has a lip that engages the under-

Fig. 3. Plastic burn-out coping may be used for fabricationof provisional restoration with appropriate mechanicalretention.

Fig. 4. Plastic burn-out copings reduced to level of solidabutments selected.

Fig. 5. Matrix for intraoral fabrication of provisional restorations.

cuts just beneath the implant shoulder. The impres-sion cap should snap into place and be able to rotatearound the abutment when properly seated.

2. Inject provisional material (Integrity; CaulkDentsply, Milford, Del.) through the opening ontop of the impression cap (Fig. 6).

3. If adequate clearance exists between the top of theimpression cap and the opposing teeth, instructthe patient to bite down to establish the occlusalsurface of the provisional restoration (Fig. 7). Theopposing teeth should be lubricated with petrole-um jelly.

4. Remove the impression cap after 90 seconds, andallow setting outside the mouth for an additional4 minutes.

5. Remove excess provisional material, and roughenthe surface with an acrylic bur.

6. Moisten the provisional restoration with acrylicresin monomer, and add acrylic resin with the use

THE JOURNAL OF PROSTHETIC DENTISTRY DUMBRIGUE, ESQUIVEL, AND GURUN

660 VOLUME 86 NUMBER 6

of the bead brush technique to complete the con-tours of the provisional restoration (Fig. 8).

Protective cap technique

An ITI cementable protective cap is available for thesolid abutment and may be used if esthetics is not aconsideration. The protective cap is available in sizesthat correspond to the 3 solid abutment heights. Theprotective cap can be modified for use as a provisionalrestoration with a technique similar to the burn-outcoping technique.

1. Select the protective cap height that correspondsto the solid abutment.

2. Place mechanical retention on the protective capby creating horizontal cuts with a separating disk.

3. Wet the surface of the protective cap withmonomer, and apply acrylic resin with the use ofthe bead brush technique to ensure that the resinengages the mechanical retention created.

4. Use a vacuum-formed matrix intraorally to pro-vide appropriate contours for the provisionalrestoration with acrylic resin. The margin config-uration of the provisional restoration is alreadyestablished in the protective cap.

DISCUSSION

Intraoral fabrication of provisional restorationswith the use of the burn-out coping, protective cap,and resin coping techniques is similar to fabricationby conventional fixed prosthodontics techniques(Fig. 5). Most restorative dentists are familiar andcomfortable with these approaches. The burn-outcoping and protective cap techniques have the advan-tage of pre-established margin configuration for theprovisional restoration, but additional costs areincurred for the ITI plastic coping and protectivecap. Since these items will not chemically bond to

Fig. 6. Provisional material injected directly throughocclusal opening of impression cap.

Fig. 8. Provisional restoration fabricated with impressioncap.

Fig. 7. Occlusion established immediately after delivery ofprovisional material.

DUMBRIGUE, ESQUIVEL, AND GURUN THE JOURNAL OF PROSTHETIC DENTISTRY

DECEMBER 2001 661

acrylic resin, retention grooves have to be created ontheir surfaces. The protective cap may be used as aprovisional restoration with no modifications ifesthetics is not a consideration.

The advantage of the resin coping technique7 is thatsimilar materials are used for the coping and the bodyof the provisional restoration. Control of margin con-figuration and contour is facilitated because the resincoping can be fabricated extraorally in the laboratorybefore the clinical appointment. Although this tech-nique requires the additional cost of a brass ITIpractice solid abutment and practice implant to serveas a die assembly, the assembly can be reused.

The impression cap technique can be used for singleimplant provisional restorations and does not require avacuum-formed matrix. The outside dimensions of theimpression cap resemble a premolar tooth and can bemodified by adding acrylic resin with the bead brushtechnique (Fig. 8). Further contouring can be accom-plished with acrylic burs. The impression cap effectivelyretracts soft tissue around the implants and confines theimplant margin. This allows the injected provisionalmaterial to record the implant margin easily and pre-vents excess material from flowing out through themargin area. Because the impression cap snaps intoplace, this technique may make multiple splinted provi-sional restorations difficult to retrieve intraorally.

REFERENCES

1. Hebel KS, Gajjar RC. Cement-retained versus screw-retained implantrestorations: achieving optimal occlusion and esthetics in implant den-tistry. J Prosthet Dent 1997;77:28-35.

2. Jones JD, Kaiser DA. A new gingival retraction impression system for aone-stage root-form implant. J Prosthet Dent 1998;80:371-3.

3. Misch CE. Contemporary implant dentistry. St. Louis (MO): Mosby-YearBook Inc; 2nd ed. 1999. p.549-73.

4. Agar JR, Cameron SM, Hughbanks JC, Parker MH. Cement removal fromrestorations luted to titanium abutments with simulated subgingival mar-gins. J Prosthet Dent 1997;78:43-7.

5. Felton DA, Kanoy BE, Bayne SC, Wirthman GP. Effect of in vivo margindiscrepancies on periodontal health. J Prosthet Dent 1991;65:357-64.

6. Esquivel JF, Welsch BB. Simplifying the bead-brush technique. Gen Dent1999;47:607.

7. Boston DW, Boberick KG. An accurate chairside technique for fabricat-ing a temporary restoration for ITI single-tooth implant. Gen Dent1998;46:638-40.

Reprint requests to:DR HERMAN B. DUMBRIGUE

BAYLOR COLLEGE OF DENTISTRY

TEXAS A & M UNIVERSITY SYSTEM HEALTH SCIENCE CENTER

3302 GASTON AVE, ROOM 601DALLAS, TX 75246FAX: (214)828-8952E-MAIL: hdumbrigue@tambcd.edu

Copyright © 2001 by The Editorial Council of The Journal of ProstheticDentistry.

0022-3913/2001/$35.00 + 0. 10/1/119248

doi:10.1067/mpr.2001.119248

Bone and soft tissue integration to titanium implants withdifferent surface topography: an experimental study in thedogAbrahamsson I, Zitzmann NU, Berglundh T, Wennerberg A,Lindhe J. Int J Oral Maxillofac Implants 2001;16:323-32.

Purpose. In an effort to improve implant prognosis when bone quality or quantity is unfavorable,implant surface modifications have been considered. This study was designed to evaluate the hardand soft tissue formed adjacent to endosseous implants with 2 different surface configurations.Material and methods. Mandibular premolar teeth were removed from 5 beagle dogs. After 3months of healing 4 self-tapping standard implants (SI) and 4 Osseotite implants (OI) wereplaced. Abutments were connected 3 months after implant placement. Block biopsies wereobtained 6 months after abutment connection. Two implants of each type were prepared for his-tometric analysis from each animal. Ground sections were used to determine bone-to-implantcontact in different zones along the implants.Results. Peri-implant soft tissue and marginal bone level were similar for both implant types. Thepercentage of bone-to-implant contact was significantly greater for OI (72.0% to 76.7%) than forSI (56.1% to 58.1%) surfaces. Bone density values were similar for both implant surfaces.Conclusions. This study corroborates the findings of previous reports that showed higher levelsof bone-to-implant contact adjacent to the roughened surface of the Osseotite implant. 40References. —SE Eckert

Noteworthy Abstractsof theCurrent Literature