A technique for the removal of provisionally placed cast restorations

A technique for the removal of provisionally cast restorations Gerald A. Heuer, D.D.S.,” Allyn

A. Smith, D.D.S.,**

placed

and Reed B. Reed***

Medical College of Georgia, School of Dentistry, Augusta, Ga.

C

ast restorations which have been tried in for margin evaluation or provisionally cemented are often difficult to remove. The problem is usually due to inability to apply effective leverage along the path of removal. Commonly used techniques to remove castings following the initial try-in or provisional cementation have included crown pullers,t straight chisels and mallets, hemostats, towel clamps, and excavators or scalers. However, these may result in scarring of the surface finish, deformation of margins, or chipping of porcelain. Although the surface may be refinished, it often results in undercontouring of the crown and usually takes valuable chairside time. Cotton gauze, rubber dam squares, and the operator’s fingers are limited by the force which can be delivered. A technique was recently reported of applying autopolymerizing resin to the facial and lingual surfaces and then using a crown puller to remove the casting.’ However, this takes about 5 minutes of chairside time. The Tofflemirex retainer and band technique as described has been successful in removing castings at the try-in stage and those which have been provisionally cemented without scarring or deformation of the casting. Full-coverage castings are most easily removed. since the technique relies on crown contour to retain the band. Partial coverage and threesurface castings have also been successfully dislodged. This technique does not work on castings where the contact areas have been wedged and the

*Assistant

Professor. Department of Restorative Dentistry, Director, Dental Auxiliary Utilization. **Associate Professor, Department of Restorative Dentistry, Coordinator. Dental Practice Dynamics. ***Senior Dental Student. ?3M Co., Costa Mesa, Calif. $Teledyne Dental Products. Elk Grove Village, Ill.

0022.3913/79/060669

+ 02$00.20/00

1979 The C. V. Mosby Co.

and

Fig. 1. The matrix retainer and band are tightened on the casting below the height of contour.

Fig. 2. The matrix retainer and band are piaccd following wedging. band cannot be passed through permanently cemented castings.

the contacts

or on

and

TECHNIQUE 1. Adapt the Tofflemire retainer and matrix band as for an amalgam procedure. The assembled retain-

THE JOURNAL

OF PROSTHETIC

I~ENTISTRY

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HEUER, SMITH,

Fig. 3. The thumb is placed below the fixed head of the retainer, pushing occlusally.

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REED

Fig. 5. The hemostat is attached to the lingual purtlon the matrix band.

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2. Place the thumb beneath the fixed head of’ the Tofflemire retainer next to the crown (Fig. 3). Using the retainer as a lever, force is applied occlusally along the path of removal. The casting should become dislodged and is retained in the matrix band (Fig. 4). When the crown is extremely difficult to remove, a hemostat may be attached to the lingual portion of the band and pulled occlusally as the thumb pushes on the fixed head of the retainer (Fig. 5).

SUMMARY A technique has been described to quickly and safely remove castings following the initial trial evaluation or provisional cementation, Fig. 4. The casting is dislodged from the preparation. er and band are placed over the crown until the gingival edge is below the height of contour. The retainer is then tightened securely (Fig. 1). Should the proximal contacts be tight, a wedge may be used to open the contact slightly, facilitating insertion of the matrix band (Fig. 2).

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REFERENCE 1. Garver, II. G., and Wisser, R. C.: .4 safe crown-removal technique. .J PROSTHET DENT 39:X, 1978. Reprint nqucsts to: GERALD A. HELTER MEDICAL COLLEGE OF GEORGIA SCHOOL OF DENTISTRY AUGUSTA, GA. 30901

DR.

JUNE 1979

VOLUME

41

NUMBER

6