Mastication and late mandibular fracture after surgery of impacted third molars associated with no gross pathology.

Purpose: This study was undertaken with the null hypothesis that in patients, fully denate or with 1 or 2 teeth missing and older than 25 years, mastication does not affect late mandibular fracture after surgical removal of impacted third molars (M3s) associated with no gross pathology.

Materials And Methods: Five hundred sixty patients, fully dentate or with 1 or 2 teeth missing and older than 25 years who had no gross pathology associated with their impacted lower M3s, were recruited in this study. They were operated on under local anesthesia using a standard technique and randomly assigned into 2 groups for nonroutine (NR group) and routine (R group) postoperative instructions. In the NR group, patients were postoperatively educated in the possibility of mandibular fracture and were given an emphasis on the necessity of limiting mastication to a soft diet for 4 weeks. In the R group, patients were given no such education or emphasis. Patients were followed up for 2 months, and data concerning patients' age and gender; tooth position, angulation, and depth; date and site of surgery; and occurrence of late mandibular fracture were recorded and statistically analyzed. A value of P less than .05 was considered statistically significant.

Results: In no patient group was there a late mandibular fracture recorded. All patients completed the follow-up period, and most of the R group patients had normal eating habits 10 to 14 days after surgery. In no patient group was there a statistically significant difference in relation to gender (P = .735), site of surgery (P = .552), class horizontal space available (P = .427), class highest portion of the M3 crown (P = .424), angulations of the teeth (P = .925), and severity of impaction (P = .445).

Conclusions: In patients, fully dentate or with 1 or 2 teeth missing and older than 25 years who have no jawbone atrophy and no systemic problems that may impair bone strength, mastication seems not to affect late mandibular fracture after surgical removal of impacted M3s associated with no gross pathology. The remote possible risk of the late fracture shown in our patients indicates the need for no special precautions.