Comparative Analysis of Two Flap Designs for the Extraction of Impacted Mandibular Horizontal Third Molars: a Multicenter Randomized Control Trial

Abstract

Most patients experience postoperative complications caused by the extraction of impacted mandibular horizontal third molars. The aim of the present study was to compare the effects of two flap designs as a refinement on the reduction of postoperative complications. One hundred eighty-eight patients with impacted mandibular horizontal third molars were included in this single-blind, multicenter, randomized control trial. The allocation was determined using a modified envelope flap (mEF) and triangular flap (TF) at 1:1 by the data manager. Postoperative complications (pain, hemorrhage, nerve paralysis, dry socket, and infection) and operation time were assessed 7 ± 1 days after surgery. In all cases, postoperative pain was significantly lower in the mEF group (P<0.05). In the subgroup analysis, postoperative pain was significantly lower in patients with low difficulty (IA, IIA, IIA, IB), which were classified by G.B. Winter classification (P<0.05). Other factors were not significantly associated with the flap design. Our study suggests that mEF resulted in less postoperative pain with a low difficulty of impacted mandibular horizontal third molars. However, the evidence at present is not sufficient to suggest the use of either flap design.