Malformations of the temporo-mandibular joint in laboratory animals and inman

In 108 fetal mice and 67 rat fetuses the normal development of the temporom andibular joint was initially explored. Then malformations of the splanchno cranium were induced and studied histologically in 287 newborn rats and 67 mice. These animals had been delivered by caesarian section after treating the pregnant dams with one of 6 different teratogens. Finally, anomalous temporomandibular joints in 53 patients were analyzed ra diographically and compared to the findings made in the above mentioned lab oratory animals. Most malformations of the temporomandibular region detecte d were found to be embryopathies. They all fit into a new teratogenic order that was established by comparing the abnormal to the normal development o f the structures involved.