Postnatal growth of the rabbit mandible

Abstract

Postnatal growth patterns in the rabbit mandible were studied as a sequel to previous reports dealing with mandibular growth and remodeling in the human and Rhesus monkey. Procedures and methods used in the present work follow those in past studies. The detailed distribution of depository and resorptive surfaces in all areas throughout the mandible was determined. Using this information, overall growth patterns in the entire bone were described and interpreted. Remodeling relationships between the different areas of the mandible were evaluated, and similarities and differences between modes of postnatal growth in the rabbit and human mandibles are discussed. Due to the general similarity of mandibular form in both species, the overall sequence of growth is parallel, including processes of condylar growth, progressive reduction of the condylar neck, and the posterior drift of the ramus. The lingual surface of the ramus in each species is predominantly depository, in contrast to the resorptive nature of the contralateral buccal side in both the human and rabbit. Growth of the mandibular body is also comparable in the two forms. Several major remodeling differences are present, however, and these are associated with certain gross anatomical dissimilarities, including differences in the coronoid process, lingual tuberosity and the mental region. The developmental basis for these differences is explained and discussed.