The Effect of Locally Applied Heat on Mandible Growth

¹ Fairleigh Dickinson University, Teaneck, New Jersey

Local heating of the rabbit mandible was achieved by a method in which the amount of heat applied to one side was maintained at a fixed level by means of a thermocouple implanted with the heat source. Best results were obtained when the mandibles received 54-60 hours of heating at a fixed increase of 4° or 5° F.

In half the mandibles the heated sides showed an increase in the postero-inferior border of the ramus over those of the unheated sides and of the unoperated controls. In some of the animals marked ridges of bone had formed about the periphery of the heated capsule. Measurements of thickness in the mandibles of some of the animals supported this observation, but most of the measurements were variable. This and the consistently greater size of both sides of the experimental mandibles over those of the unoperated controls, suggest that factors other than heat may be contributing to the changes noted in the bone. The elimination of these factors are now being continued in our laboratory.