Efficacy of bonded and nonbonded amalgam in the treatment of teeth with incomplete fractures.

BACKGROUND

This clinical study compared the efficacy of adhesive-retained vs. pin-retained complex amalgam restorations in the treatment of molars with incomplete fractures. Both relief of chewing pain and cold sensitivity were evaluated at two weeks, three months and one year.

METHODS

The authors treated 38 patients with a chief complaint of chewing sensitivity on vital molar teeth (40 teeth in the study). A random-number generator determined the treatment method for each tooth. Twenty teeth received bonded amalgam restorations. Twenty teeth received amalgapins or threaded pins to retain the amalgam. Teeth were evaluated for postoperative chewing sensitivity. A visual analog pain scale was used to evaluate cold response to a skin-refrigerant-soaked cotton pellet at each visit. After 12 months, all 40 teeth were available for evaluation.

RESULTS

Chewing pain was completely eliminated in all but one tooth. A Student's t-test found no significant difference (P > .05) in preoperative cold sensitivity between the bonded and nonbonded groups. A paired t-test comparison indicated that the teeth in the bonded group were significantly less sensitive to cold after three months and 12 months than they were at the time of the baseline measurements (P < .0001). A paired t-test indicated no significant difference between preoperative and postoperative cold sensitivity scores for teeth in the nonbonded group (P > .05).

CONCLUSIONS

Both adhesively bonded and mechanically retained complex amalgam restorations were successful in resolving chewing sensitivity in cracked molars. For 39 of 40 teeth, chewing sensitivity did not return during the one-year follow-up period. At three months and 12 months, cold sensitivity was reduced in the bonded restorations. At all three time periods, cold sensitivity remained similar to baseline levels for the mechanically retained restorations.

CLINICAL IMPLICATIONS

Incomplete tooth fracture in molars can be successfully treated by covering fractured cusps with amalgam restorations. This study excluded teeth with prolonged sensitivity to a cold stimulus or those with periodontal evidence of root fracture. With these exclusions, elimination of chewing sensitivity was predictable. Teeth restored with bonded restorations experienced a decrease in sensitivity to a cold stimulus at three months and at 12 months, but not at two weeks. The cold sensitivity of teeth restored with nonbonded restorations was similar at baseline, two weeks, three months and one year.