Flap design and mandibular third molar surgery: a split mouth randomized clinical study

The aim of this study was to investigate the effects of two commonly used flap designs (envelope and triangular) used for the removal of mandibular third molars (M3) on postoperative morbidity. 19 patients with bilateral symmetrically impacted mandibular M3 were studied using a split mouth design. Swelling, pain and trismus measures were recorded on days 2, 7 and 14; periodontal indices were recorded on days 7 and 14, one final measure of probing depth on the distal aspect of the mandibular second molar (M2) was taken at the last follow up appointment. Data were analysed using the chi(2) test, the Mann Whitney U-test and Pearson's correlations. The mean age of the patients was 21.4 +/- 2.3 years (+/- SD). Facial swelling and the reduction in mouth opening were significantly greater in the early postoperative period (P < 0.05) with pyramidal flap designs. There was no significant difference in pain scores, plaque accumulation and bleeding on probing indices between the two flap designs (P > 0.05). Probing depth was significantly greater with envelope flaps in the early postoperative period (P < 0.005). In conclusion, flap design in mandibular M3 surgery has an effect on postoperative recovery.