These data suggest that the spread of root resorption is associated with inflammation. This study also suggests that the capacity for repair of root resorption is diminished with greater severity of periodontitis.

Our results indicate that the synthesis of matrix components becomes more important relative to proliferative activity. The traditionally defined histological layers (zones I, II, III, and IV) are not clearly distinguishable in rabbits of this age. In 6- and 7-week old animals only a "surface" (I/II) and a "deep" layer (III) can be distinguished. By 8 weeks, zones I and II are well defined but the mineralization front (marking the boundary between zones III and IV) is still absent.

The severity of periodontal disease increases the extension and the depth of the radicular resorption, and the presence of antagonist forces aggravates the resorption.