The Effects of the Short Latent Period During Destraction osteogenesis : An Experimental Study in the Mandibles Rabbits

ABSTRACT

To evaluate the effect of shortening the latent period for distraction osteogenesis, the authors experimented with distraction osteogenesis for a 24-hour latent period in the mandibles of rabbits. This study was carried out on 32 New Zealand white rabbits, each weighting 2000 to 2500 gm. Twenty animals were used for the control group and 12 for the experimental group. A unilateral external fixation device was applied to the left mandible. The mandibles were lengthened at 1 mm per 24 hours for 10 days. Five rabbits from the control group and three from the experimental group by random selection were sacrificed on the first day, and at the second, fourth and eighth week of the consolidation period. After lengthening bone densities at the site of the left mandibular bony lengthening were measured by quantitative computer tomography (QCT) and dual energy x-ray absorptiometry (DXA). As a result, the DXA value showed no difference compared to the control group after two week's consolidation. The trabeculae were thicker and had begun to be surrounded by lamellar bone both in the control and experimental groups histologically. In conclusion, the results of this study indicate that the osteogenetic effect in the experimental group was nearly the same as in the control group. If stable fixation and minimal periosteal dissection were performed during the procedure, the latent period would not be an important factor in distraction osteogenesis of membranous bone.