Differential Growth and Healing of Bones and Teeth

Abstract

A series of experiments was performed in turtles, rodents, lagomorphs, dogs, and monkeys to determine and correlate differential growth and healing of bones and teeth. Vital stains, radiopaque implants in conjunction with serial radiography, autoradiography, histology, and other methods were employed. Histologic differences and rate of endochondral (tibia, rib, base of skull, and mandibular condyle) and nasal cartilaginous septal growth were noted. Similarly, differences were observed in growth between five facial sutures and also for the same suture at different times. The nasal bone side of the frontonasal suture grew about twice as fast as the frontal bone side. In the turtle shell the midsagittal suture grew faster than a transverse suture. A variety of differences in rate of appositional (and resorptive) growth were noted at different sites of the mandible and nasal bone region. Generally, there was deposition of bone along the posterior border of the mandibular ramus and resorption of bone along the anterior border. Variations in the volume of the orbital contents influenced orbital growth. Bone was highly reactive, while enamel and dentin were nonreactive, to trauma.