[Histologic observation of upper central incisors after surgical immediate torsion].

The purpose of this study is to verify the treatment results of rotated teeth by using surgical immediate torsion method. Seven upper central incisors in four monkeys were chosen in our experiment. The surgical treatment was accomplished by rotating the teeth in about 45 degree. The animals were sacrificed at 2, 3, 4 and 12 weeks after operation. The results showed that two of seven dental pulps were necrosis, three were injured and two were normal. Absorption of dental cementum and dentine occurred at the apex and the middle third of the root. There was no evidence of ankylosis between the tooth and bone tissues. According to our experiment, we think that the surgical immediate torsion method for treating rotated teeth is not available.