Abstract
To elucidate the process in which the muscle attachment migrates during growth, the attachment of the deep layer of the masseter muscle to the rat mandible was examined by light microscope autoradiography using 3H-proline.
Most of the silver grains were concentrated in the cytoplasm of fibrocartilage cells in the tendinous attachment and transitional zone, and also fibroblasts in the periosteal attachment at 30min after the 3H-proline injection. At 4h after the 3H-proline injection, silver grains in atteched fibers increased. These results suggest that collagen fiber was actively formed by fibrocartilage cells in the tendinous attachment and transitional zone, and by fibroblasts in the periosteal attachment.
It was concluded that, in rats, attachment of the deep layer of the masseter muscle to the mandible migrated to the mandible, maintaining its relative position by the active remodeling of the attached fiber which was embedded in the bone.
