Experiment On Tooth Movement In New Bone After Distraction Osteogenesis

Objective Moving the teeth into new bone after distraction osteogenesis, so patients could have been avoided extraction in the clinical, in order to maintain stability in the number of teeth. Distraction osteogenesis is different from the histological features of normal bone tissue , mastering suitable time and power values of the movement will greatly shorten the treatment cycle, as well as the smallest influence of periodontal,gum,alveolar bone and root.This can greatly shorten the time of moving teeth to meet the the patient's requirements in the shortest time.Mandibular distraction osteogenesis surgery is carried out in the right side of the 8 beagle dogs, and then from the second week and sixth week after fixed period of distraction osteogenesis, at the same strength value , move the teeth into the new bone area respectively. To compare the similarities and differences of tooth movement at different time points in new bone after distraction osteogenesis, as well as the effects of the periodontal tissue and dental tissue, explore the right time of tooth movement after distraction osteogenesis .Methods 8 healthy adult beagle dogs were carried out in experiment. The mandible is broken off between the third premolar and the fourth premolar for distraction osteogenesis, producing a toothless new bone area. Then uses a complete random way to classify eight beagle dogs into two groups. Starting tooth movement from the second week of fixed period after distraction osteogenesis is group I, and the sixth week of fixed period after distraction osteogenesis is group II. After 4 weeks, animals were killed directly. Application of physical measurements, X-ray, HE staining and general specimens is observed, physical measurement's data use repeated-measures analysis of variance, P<0.05 stand for the difference statistically significant. Root of mobile teeth, periodontal and alveolar bone were analyzed.Results All dogs survive to the expected time, gross observation of the specimens after the execution and new bone is formed well. At the second week and sixth week of fixed period after distraction osteogenesis, with the same force value, pulling teeth to the new bone area, the distance between the third premolar and fourth premolar decreases with time , the interclass has a statistically significant difference (P<0.05), the interblock was statistically significant(P<0.05).Conclusions (1) A new bone area without teeth what distraction osteogenesis produce , under the action of suitable force, moving tooth into the new bone area is feasible.(2) In the same 50g force values, the speed of tooth movement ,the second week of fixed period after distraction osteogenesis is faster than the sixth week.(3)Absorption of dental and periodontal tissue ,the second week is more serious than the sixth week .