Composite indirect-direct method for fabricating multiple-unitprovisional restorations

Herman B. Dumbrigue, DDMa

Baylor College of Dentistry, Texas A & M University System Health Science Center, Dallas,Texas

This article describes a method for fabricating multiple-unit provisional restorations by use of the indi-rect-direct method without the need for abutment preparation on diagnostic casts. Composite is usedwith fiber reinforcement to create a provisional shell in a vinyl polysiloxane matrix. This method re-duces chair time, as well as laboratory time required to fabricate provisional restorations. Control ofrestoration contours and incisal edge position is also enhanced. (J Prosthet Dent 2003;89:86-8.)

Fabrication of provisional restorations is an impor-tant procedure in fixed prosthodontics. Provisional res-torations must satisfy the requirements of pulpal protec-tion, positional stability, occlusal function, ability to becleansed, margin accuracy, wear resistance, strength,and esthetics.1 Provisional restorations serve the criticalfunction of providing a template for the final restora-tions once they have been evaluated intraorally.

Provisional restorations may be made directly2,3 onprepared teeth with the use of a matrix or indirectly4,5 bymaking an impression of the prepared teeth. A combi-nation indirect-direct technique6 is also possible withfabrication of a preformed shell that is relined in-traorally. The direct technique is the most commonlyused method for fabrication of provisional restorations,in spite of the disadvantages associated with this tech-nique.7 Margins obtained from direct techniques are lessaccurate than those resulting from indirect methods,8and autopolymerizing acrylic resin may subject the pulpto chemical and thermal insult.9 The popularity of thistechnique lies in its relative convenience, since labora-tory procedures involved are minimal. The indirect tech-nique requires making an irreversible hydrocolloid im-pression of the prepared teeth and fabricating theprovisional restorations in the laboratory. Although thisprocedure may be partially delegated to auxiliary per-sonnel, material requirements, laboratory time, andchair time for the patient is increased. With the combi-nation indirect-direct technique, chair time can be re-duced since the provisional shell is fabricated before thepatient’s appointment. Enhanced control over restora-tion contours minimizes the time required for chairsideadjustments. In addition, a smaller amount of acrylicresin will polymerize in contact with the prepared abut-ment, resulting in decreased heat generation, chemicalexposure, and polymerization shrinkage compared tothe direct technique. The technique described for com-bination indirect-direct provisional restorations requires

abutment preparation on diagnostic casts to create spacefor restorative material.6 Abutments are typically pre-pared conservatively to produce a thin-walled provi-sional shell.

This article describes an alternative method for fabri-cating multiple-unit provisional shell restorations thatdoes not require abutment preparation on diagnosticcasts. This method reduces chair time, as well as labora-tory time required to fabricate provisional restorations.

TECHNIQUE1. Complete the diagnostic wax-up on articulated

casts. Ensure that gingival margins are well delin-eated in the wax-up (Fig. 1).

2. Make a vinyl polysiloxane (VPS) putty impression(Extrude XP; Kerr, Romulus, Mich.) of the wax-upin a stock tray to serve as a matrix for the provisionalshell.

3. If use of fiber reinforcement (Construct Reinforc-ing Fiber System; KerrLab, Orange, Calif.) is de-sired, place a thin layer of flowable composite (Con-struct Resin; KerrLab) on the lingual surface of theVPS matrix and adapt a strip of fiber reinforcementover the composite. Light polymerize for 40 sec-

aAssociate Professor and Assistant Program Director, Advanced Ed-ucation in General Dentistry.

Fig. 1. Diagnostic wax-up with gingival margins clearly de-lineated.

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onds (Triad 2000 light curing unit; Dentsply, York,Pa.). Use of fiber reinforcement has been shown toincrease the fracture resistance of provisional resto-rations.10

4. Place approximately 0.5 to 1.0 mm of hybrid com-posite (Point 4; Kerr) over the lingual surface. Thecomposite should be gently adapted to the VPSmatrix to minimize lifting. Place composite up tothe line corresponding to the gingival margin tominimize the need for adjustments to the provi-sional shell after polymerization. Light polymerizefor 40 seconds.

5. Place composite on the facial surface as described instep 4 (Fig. 2). For posterior provisional restora-tions, use flowable composite (Revolution; Kerr) onthe occlusal area because it may be difficult to adapthybrid composite without the material lifting off theVPS matrix (Fig. 3).

6. Retrieve the composite provisional shell from theVPS matrix (Fig. 4). The shell thickness may bedecreased by use of diamond burs.

7. After tooth preparation, reline the provisional shellwith bis-acryl composite (Integrity; Dentsply/Caulk, Milford, Del.) using the margin of the pro-visional shell as a guide for seating. The provisionalmargin should approximate the soft tissue marginsintraorally. Alternatively, the VPS matrix may betrimmed and used as an intraoral index for bettercontrol of incisal edge position (Fig. 5).

8. Trim excess material with diamond burs. Marginsmay be perfected intraorally with flowable compos-ite.

9. Finish, polish, and cement the provisional restora-tions after fit, esthetics, and occlusion have beenverified (Fig. 6).

SUMMARY

A variation of the indirect-direct method for fabricat-ing provisional restorations is described. This methoddoes not require abutment preparation on diagnosticcasts and thus reduces laboratory time. Composite isused with fiber reinforcement to create a provisional

Fig. 2. Composite adapted to facial and lingual surfaces ofvinyl polysiloxane matrix.

Fig. 3. Flowable composite applied to occlusal surface forfabrication of posterior provisional shell.

Fig. 4. A, Posterior composite provisional shell. B, Anterior composite provisional shell with lingual fiber reinforcement.

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JANUARY 2003 87

shell in a VPS matrix. Use of fiber reinforcement hasbeen shown to increase the fracture resistance of provi-sional restorations.10 Three kinds of composite are usedwith this technique: light-polymerized hybrid compos-ite for the shell, auto-polymerizing bis-acryl compositeas reline material, and flowable light-polymerized com-posite for improving marginal adaptation. Flowablecomposite is also used to adapt fiber reinforcement onthe lingual aspect of the VPS matrix, as well as to formthe occlusal shell for posterior provisional restorations.Enhanced control over restoration contours and incisaledge position reduces chair time required to fabricateprovisional restorations.

REFERENCES1. Shillingburg HT Jr, Hobo S, Whitsett LD. Fundamentals of fixed prosth-

odontics. 3rd ed. Chicago: Quintessence Publishing Co;1997. p. 225-7.2. Miller SD. The anterior fixed provisional restoration: a direct method. J

Prosthet Dent 1983;50:516-9.3. Fehling AW, Neitzke C. A direct provisional restoration for decreased

occlusal wear and improved marginal integrity: a hybrid technique. JProsthodont 1994;3:256-60.

4. Boberick KG, Bachstein TK. 1998 Judson C. Hickey Scientific WritingAward. Use of a flexible cast for the indirect fabrication of provisionalrestorations. J Prosthet Dent 1999;82:90-3.

5. Small BW. Indirect provisional restorations. Gen Dent 1999;47:140-2.6. Bennani V. Fabrication of an indirect-direct provisional fixed partial den-

ture. J Prosthet Dent 2000;84:364-5.7. Campagni WV. Fabricate provisionals to function and appear as if they

were permanent restorations. Cosmetic Dent 1991;4:1-4.8. Crispin BJ, Watson JF, Caputo AA. The marginal accuracy of treatment

restorations: a comparative analysis. J Prosthet Dent 1980;44:283-90.9. Grossman LI. Pulp reaction to the insertion of self-curing acrylic resin

filling materials. J Am Dent Assoc 1953;46:265-9.10. Vallittu PK. The effect of glass fiber reinforcement on the fracture resis-

tance of a provisional fixed partial denture. J Prosthet Dent 1998;79:125-30.

Reprint requests to:DR HERMAN B DUMBRIGUE

BAYLOR COLLEGE OF DENTISTRY

TEXAS A & M UNIVERSITY SYSTEM HEALTH SCIENCE CENTER

3302 GASTON AVENUE, ROOM 601DALLAS, TX 75246TEL: (214) 828-8137FAX: (214) 828-8952E-MAIL: hdumbrigue@tambcd.edu

Copyright © 2003 by The Editorial Council of The Journal of ProstheticDentistry.

0022-3913/2003/$30.00 � 0

doi:10.1067/mpr.2003.8

Fig. 5. A, Modified vinyl polysiloxane matrix may be used toseat anterior provisional restorations during relining proce-dure. B, Control of incisal edge position enhanced with vinylpolysiloxane matrix.

Fig. 6. Completed full-mouth composite provisional restora-tions.

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