Abstract
An attempt was made to investigate the effect of mechanical force on the collagenolytic activity of the periodontal membrane of rabbits during experimental tooth movement, by means of sterile incubation of the excised tissues on the reconstituted collagen gel plate in vitro. An orthodontic elastic band was applied between lower incisor and first molar so as to exert about 100 g reciprocal force upon the intermediate tissues for 1, 3, 5, 7 and 21 day periods respectively. It was demonstrated that the periodontal membrane of first molar subjected to compressive force had the ability of collagenolysis, and that the appearance of collagenolytic activity was dependent upon the duration of force application. The results suggest that the incidence of collagenolytic activity may be closely related to the deposition of fresh granulation tissue accompanied by vascularity and osteoclasts.
