Supra-alveolar periodontal healing of auto- and allotransplanted teeth in monkeys.

Although intra-alveolar healing of allotransplanted teeth often shows pathological changes due to rejection of the tooth graft, previous clinical findings seem to indicate that the supra-alveolar part of the allografts heals differently, which is of significant prognostic value. The aim of the present study was to determine the healing of the cervical part of the periodontium of auto- and allotransplanted mature teeth in monkeys. In 4 adult, immunologically unmatched, green vervet monkeys 16 mature permanent maxillary and mandibular incisors were extracted, endodontically treated and either auto- or allotransplanted; 8 untreated neighbouring incisors served as controls. Block biopsies including part of the tooth and the adjacent vestibular tissues were obtained after a healing period of 8 weeks. The biopsies were decalcified in EDTA and embedded in Epon. In semi-thin section (1.5 microns) the morphology of the supra-alveolar periodontal tissues was analysed in the light microscope. The orientation of the connective tissue fibres close to the root surface was found to be more parallel to the root surface of allotransplants compared with autografts, while in the control teeth the fibres were generally oriented perpendicular to the root surface. Resorption of the root was seldom found in the supra-alveolar portions of any of the transplanted teeth. The junctional epithelium had migrated slightly apically onto the root surfaces of allotransplanted teeth. The gingival connective tissue adjacent to allotransplanted teeth showed a significantly increased number of lymphocytes compared with autografts and controls.(ABSTRACT TRUNCATED AT 250 WORDS)