Rate and anchorage loss during en-masse retraction between friction and frictionless mechanics: A randomized clinical trial

Abstract

Objective: To compare rate and anchorage loss during en-masse retraction of anterior maxillary teeth between friction mechanics (FM) and frictionless mechanics (FLM). Setting and Sample Population: Thirty-eight patients requiring en-masse retraction of protruded anterior maxillary teeth were randomly allocated into FM and FLM groups. Methods: En-masse retraction with sliding mechanics (FM) using an elastomeric chain was compared with continuous mushroom loop archwire mechanics (FLM). Study models and lateral cephalograms were taken before (T1) and immediately after retraction (T2). The primary outcome was the rate of en-masse retraction. Anchorage loss was the secondary outcome. Intergroup comparison was performed using an independent t test (P