A histological study of tooth allografts transplanted to untreated and immunologically prepared mice

Ten-day-old mouse teeth were grafted subcutaneously into adults of an unrelated strain which were either untreated or had rejected a skin graft from the same strain as the tooth donors. First set allografts degenerated rapidly after grafting and were only sparsely repopulated subsequently. No cell-mediated immune response was observed. In contrast, second set allografts were heavily infiltrated with mononuclear leukocytes which persisted throughout the study, although the coronal pulp was never involved. It was suggested that first set allografts did not suffer a cell-mediated response because rapid degeneration of the cellular components removed the immunogenic target tissue before the host response could be effected.