March 1, 2003
by Emma Yu, DDS
As practitioners of general dentistry, restoring denture abutment teeth is a necessity. With the aging of the general population this type of procedure will be more and more common in our daily treatment schedule. The challenge of restoring a denture abutment tooth is the fit of the existing denture afterwards. Most patients can readily tell if the denture is not fitting quite the same. With the wonderful dental materials that are presently at our disposal, we can very easily record the existing occlusal anatomy of the denture abutment to facilitate the proper seating of the existing denture.
MATERIALS AND METHODS
Establish the need to replace or restore the denture abutment tooth. The operator should carefully review the occlusal anatomy to determine if any further modification is necessary. For example, if there are any voids, missing fillings or tooth material it will need to be replaced with temporary space filler before the occlusal anatomy is recorded. Cavit does this nicely. If this area involves the denture clasp or rest, the denture would be seated at this point when the Cavit is still soft. A sectional impression of the tooth is taken with a clear impression material. Both Peppermint Snap Clear Bite Registration (Discus Dental Inc.) (Fig. 1) and RSVP Clear Matrix Impression Material (Cosmedent Inc.) (Fig. 2) work great. It is important to establish sufficient occlusal stop in this sectional impression to aid in the future seating of this matrix. This is achieved by including adjacent dentition or a significant amount of the residual ridge in the sectional impression. Rubber dam isolation is achieved after the patient is anesthetized. After the preparation of the tooth is completed, a matrix is placed before filling the cervical portion of the restoration with composite resin.
The matrix minimizes the amount of flash that would require trimming. At this point the matrix and the rubber dam is removed. If there is contamination of the preparation with saliva then the entire surface is etch, prime and bond again. The occlusal portion of the tooth is now filled with composite and the clear sectional impression matrix is placed onto the uncured resin. After the occlusal stop has been achieved the resin is cured through the clear impression matrix material ten seconds from all accessible surfaces. The matrix is removed at this point. The composite is further cured to completion. Any access is trimmed off. The denture is placed and any necessary adjustment should be minimal. The fit of the denture is confirmed with the patient.
The patient presents with a fractured amalgam in the second premolar (Fig. 3). The existing PUD is inserted to assess the fit of the denture (Fig. 4). A sectional impression is taken preoperatively with the clear impression material to record the occlusal anatomy (Fig. 5). Rubber dam isolation is achieved after local anaesthetic (Fig. 6). The existing amalgam restoration and recurrent decay have been removed (Fig. 7). Contact Molar Band is placed prior to the restoration of the gingival portion of the tooth (Fig. 8). The gingival portion of the restoration is placed and cured (Fig. 9). The occlusal portion of the restoration is placed and the sectional impression matrix is placed on the uncured composite to transfer the preoperative occlusal anatomy. The composite resin is cured through the clear impression material after the occlusal stop have been confirmed (Fig. 10). The final cure of the resin is done after the matrix have been removed and the restoration is polished (Fig. 11). The PUD is inserted and the proper seating of the denture is confirmed with the patient (Fig. 12).
The patient presents with a fracture and open margin with recurrent decay on the first molar (Fig. 13). The existing PUD is seated to assess the fit of the denture (Fig. 14). The sectional impression is taken preoperatively (Fig. 15). The rubber dam has been removed after the preparation is completed. In this case the Tofflemire matrix could not be placed with the rubber dam clamp on. Isolation is established with Dri-Angle and the cervical portion of the composite resin is placed and cured (Fig. 16). The occlusal portion of the restoration is filled with composite resin. The sectional matrix is placed over the uncured composite resin. Check for proper seating of the matrix before curing the composite through the matrix to establish the preexisting occlusal anatomy (Fig. 17). The composite restoration is completely cured after the removal of the matrix. Note: there is minimal flash present (Fig. 18). After the restoration is trimmed and polished the PUD is inserted and the patient confirms the fit of the denture (Fig. 19).
The patient presents with a fractured restoration on the first premolar (Fig. 20). The fit of the existing PUD is established (Fig. 21). Cavit is used to temporarily restore the fractured restoration (Fig. 22). At this time the PUD should be seated to ensure good adaptation to the temporary restoration. A sectional impression is taken of the restoration (Figs. 23 & 24). Rubber dam isolation is established (Fig. 25). The Contact Molar Band is placed after the preparation is completed (Fig. 26). The cervical portion of the restoration is placed and the composite resin is cured (Fig. 27). The rubber dam has been removed. The isolation of the tooth is re-established. The entire preparation and new composite is etched, primed and bonded. The occlusal portion of the restoration is placed but not cured (Fig. 28). The sectional matrix is placed on top of the uncured composite resin and the restoration is cured through the clear matrix (Fig. 29). The matrix is removed at this point and the restoration is cured completely (Fig. 30). The restoration has been trimmed and polished (Fig. 31). The proper seating of the PUD is confirmed with the patient (Fig. 32).
Restoring denture abutments does not require endless adjustments when we have the correct armamentarium. By using the method mentioned above, we find that it takes about the same amount of time to restore abutment teeth as “regular” teeth.
Dr. Yu graduated from University of Toronto. She is the Accreditation Chair with the Ontario Academy of General Dentistry and a member of the American Academy of Cosmetic Dentistry. Dr. Yu maintains a private practice in Burlington, ON.
Oral Health welcomes this original article.