LOWER 3RD MOLAR DEVELOPMENT SUBSEQUENT TO 2ND MOLAR EXTRACTION

Development and eruption of lower third molars was examined in 63 subj ects who were treated by extraction of second molars. Changes in mesio distal and buccolingual lower third molar angulation were measured on 60 degrees cephalograms taken before extraction and 3 or more years la ter. The final position of lower third molars was assessed on models a t the end of the observation period by using a scoring system. All low er third molars erupted in periods ranging from 3 to 10 years after ex traction. Ninety-nine percent of the third molars uprighted mesiodista lly, but few became as upright as the second molars they replaced. Mod el analysis showed that 96% of the lower third molars erupted in good or acceptable positions.