LONG-TERM SURVIVAL OF AUTOGRAFTED RABBIT'S TEETH IN TIBIA AND HISTOPATHOLOGICAL OBSERVATIONS.

Abstract

A total of 133 rabbits were used for an experiment on autotransplantation of the incisor into the bone marrow of the tibia. The experiments were divided into four groups according to the grafts : Group A : basal end of the incisor with germinative regions ; Group B ; germinative region only ; Group C ; basal end of incisor only, excluding dental pulp and germinative regions ; Group D ; dental pulp only. Growth of the grafted teeth was serially observed by X-ray, and histopathological investigations were performed under electron microscope, together with histochemical analysis by immunohistochemistry.
The transplanted teeth tissues in Groups A and B grew until the end of the 12-month observation period. In Group A, transplanted teeth grew like normal teeth in the bone marrow. In Groups A and B, specific histological features like fibro-osseous and odontoma-like conformations were observed. Fibro-osseous conformations were similar to human fibro-osseouss lesion containing cementoid and osseous tissues. Odontoma-like conformations were similar to human odontoma as well, with the appearance of irregular dentine and enamel epithelium.
These histological findings were confirmed by electron microscope and immunohistochemistry. Anti-BrdU antibody revealed activated proliferating cells in the progenitive region and fibro-osseous conformations. In Groups C and D, transplanted tissues disappeared during the observation period. The experiment revealed that autotransplantation of rabbit incisors in the tibia was a useful animal model for elucidating the histogenesis of human fibro-osseous lesions of the mandible and odontoma.