Me. Richardson et A. Richardson, LOWER 3RD MOLAR DEVELOPMENT SUBSEQUENT TO 2ND MOLAR EXTRACTION, American journal of orthodontics and dentofacial orthopedics, 104(6), 1993, pp. 566-574
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.