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Atraumatic removal of porcelain veneer crowns after interim cementation
Atraumatic removal of porcelain veneer crowns aI!ter interim cementation G. J. Chiche, D.D.S.,* and M. G. Mikhail, Louisiana
State University,
School of Dentistry,
D.D.S., M.S.**
New Orleans,
T
interim cementation is advocated in extensive fixed prosthodontic procedures prior to remounting and final cementation. The consistency of the temporary cement should allow for a convenient removal of the cemented units, but the cement integrity should not be disrupted or premature loosening, marginal leakage, and pulpal trauma can occur. Situations arise in which the careful removal of porcelain veneer crowns is unsuccessful. Short clinical *Assistant Professor, Department of Fixed Prosthodontics **Associate Professor, Department of Fixed Prosthodontics.
La.
crowns with minimum height of contour and highIy polished surfaces offer an unfavorable prognosis for prompt removal (Fig. 1). The forceful use of hemostatic forceps and crown removers may cause porcelain crazing, root fracture, marginal damage, or undesirable etching of the glazed porcelain surfaces. This article describes a technique for atraumatic removal. of porcelain veneer crowns.
TECHNIQUE 1. Mix cold curing acrylic resin in a dappen dish. 2. When it reaches the doughy stage, moId the acrylic
Fig. 2. Short clinical crowns are difficult to remove following cementation. Fig. 2. Acrylic resin is formed around crowns and into interpoximal spaces. Fig. 3. Forceps are applied to acrylic resin surrounding crown. 164
FEBRUARY
1985
VOLUME
53
NUMBER
2
ATRAUMATIC
CROWN
REMOVAL
Fig. 4. Crown has been loosened from tooth.
Fig. 5. Acrylic resin is removed from teeth. resin around the cemented crowns and press it into the proximal dental spaces. Finger pressure is effective until initial setting takes place (Fig. 2). 3. Firmly grasp the acrylic resin-crown assembly with a curved hemostatic forceps. The compressive strength of porcelain and the cushion effect of the acrylic resin allow a firm grasp that will prevent slippage of the acrylic resin from the crown (Fig. 3). 4. A gentle buccolingual torquing is effected that is
sufficient to disrupt the cement integrity until atraumatic loosening occurs (Fig. 4). 5. Separate the acrylic resin from the crown. No burnout is necessary (Fig. 5). Refinnt requests to. DR. G. J. CHICHE LOUISIANASTATE UNIVERSITY SCHOOLOF DENTISTRY NEW ORI.EANS,LA 701 I9
Margin placement of esthetic veneer crowns. Part IV: Postoperative patient attitudes B. J. Crispin, D.D.S., M.S.,” J. F. Watson, D.D.S., M.S.,** and K. Shay, D.D.S.*** University of California, School of Dentistry,
Los Angeles, Calif
larts I through III of this study presented data which indicated that restorative dentists can place more esthetic veneer crown margins supragingivally without a compromise of esthetics, lb3In view of the potential benefits of supragingival crown margin placement for both the patient and the dentist such treatment should be done. Part III of the study3 pointed out a shortcoming of the study: many of the subjects surveyed did not require placement of an esthetic veneer crown. Thus the decision they made would not affect them personally. Fear of patient rejection must certainly influence the approach to restorative treatment. *Associate Professor, Section of Fixed Prosthodontics. **Associate Clinical Professor, Section of Operative Dentistry. ***Research Associate. THE JOURNAL
OF PROSTHETIC
DENTISTRY
The purpose of this part of the study was to assessthe attitudes of subjects who had existing esthetic veneer crowns with supragingivally positioned margins.
METHOD Subjects with at least one supragingival crown margin, which was defined as a veneer crown or retainer with all or part of the facial margin positioned coronal to the free gingival margin, were selected from the general patient population of the clinic. The tooth numbers were recorded, and the esthetic analysis described in Part I of the study’ was completed. Margins were scored as showing or not showing for both a normal and an exaggerated smile. If any portion of the margin was visible it was scored as showing (Figs. 1 and 2). 165
State University,
School of Dentistry,
D.D.S., M.S.**
New Orleans,
T
interim cementation is advocated in extensive fixed prosthodontic procedures prior to remounting and final cementation. The consistency of the temporary cement should allow for a convenient removal of the cemented units, but the cement integrity should not be disrupted or premature loosening, marginal leakage, and pulpal trauma can occur. Situations arise in which the careful removal of porcelain veneer crowns is unsuccessful. Short clinical *Assistant Professor, Department of Fixed Prosthodontics **Associate Professor, Department of Fixed Prosthodontics.
La.
crowns with minimum height of contour and highIy polished surfaces offer an unfavorable prognosis for prompt removal (Fig. 1). The forceful use of hemostatic forceps and crown removers may cause porcelain crazing, root fracture, marginal damage, or undesirable etching of the glazed porcelain surfaces. This article describes a technique for atraumatic removal. of porcelain veneer crowns.
TECHNIQUE 1. Mix cold curing acrylic resin in a dappen dish. 2. When it reaches the doughy stage, moId the acrylic
Fig. 2. Short clinical crowns are difficult to remove following cementation. Fig. 2. Acrylic resin is formed around crowns and into interpoximal spaces. Fig. 3. Forceps are applied to acrylic resin surrounding crown. 164
FEBRUARY
1985
VOLUME
53
NUMBER
2
ATRAUMATIC
CROWN
REMOVAL
Fig. 4. Crown has been loosened from tooth.
Fig. 5. Acrylic resin is removed from teeth. resin around the cemented crowns and press it into the proximal dental spaces. Finger pressure is effective until initial setting takes place (Fig. 2). 3. Firmly grasp the acrylic resin-crown assembly with a curved hemostatic forceps. The compressive strength of porcelain and the cushion effect of the acrylic resin allow a firm grasp that will prevent slippage of the acrylic resin from the crown (Fig. 3). 4. A gentle buccolingual torquing is effected that is
sufficient to disrupt the cement integrity until atraumatic loosening occurs (Fig. 4). 5. Separate the acrylic resin from the crown. No burnout is necessary (Fig. 5). Refinnt requests to. DR. G. J. CHICHE LOUISIANASTATE UNIVERSITY SCHOOLOF DENTISTRY NEW ORI.EANS,LA 701 I9
Margin placement of esthetic veneer crowns. Part IV: Postoperative patient attitudes B. J. Crispin, D.D.S., M.S.,” J. F. Watson, D.D.S., M.S.,** and K. Shay, D.D.S.*** University of California, School of Dentistry,
Los Angeles, Calif
larts I through III of this study presented data which indicated that restorative dentists can place more esthetic veneer crown margins supragingivally without a compromise of esthetics, lb3In view of the potential benefits of supragingival crown margin placement for both the patient and the dentist such treatment should be done. Part III of the study3 pointed out a shortcoming of the study: many of the subjects surveyed did not require placement of an esthetic veneer crown. Thus the decision they made would not affect them personally. Fear of patient rejection must certainly influence the approach to restorative treatment. *Associate Professor, Section of Fixed Prosthodontics. **Associate Clinical Professor, Section of Operative Dentistry. ***Research Associate. THE JOURNAL
OF PROSTHETIC
DENTISTRY
The purpose of this part of the study was to assessthe attitudes of subjects who had existing esthetic veneer crowns with supragingivally positioned margins.
METHOD Subjects with at least one supragingival crown margin, which was defined as a veneer crown or retainer with all or part of the facial margin positioned coronal to the free gingival margin, were selected from the general patient population of the clinic. The tooth numbers were recorded, and the esthetic analysis described in Part I of the study’ was completed. Margins were scored as showing or not showing for both a normal and an exaggerated smile. If any portion of the margin was visible it was scored as showing (Figs. 1 and 2). 165