Relationship between Biological Apatite Alignment and Hemi-occlusion in Rabbit Mandibular Cortical bone

Abstract

Biological apatite (BAp) crystallite c-axis alignment is known to one of the factor in mechanical function in bone. The purpose of this study was to investigate BAp crystallite alignment as a potential factor in the evaluation of bone strength in clinical practice by evaluating the relationship between BAp alignment and bone mineral density (BMD) using an experimental hemi-occlusion model in rabbit mandibular cortical bone.
A higher degree of BAp crystallite c-axis alignment was observed in the mesiodistal direction on the non-occlusion than on the occlusion side in the alveolar area, a tendency that was not seen in the base of the mandible. No significant differences were observed in BMD between the alveolar area and the base of the mandible or between the occlusion and non-occlusion sides. No correlation was observed between BAp crystallite alignment and BMD.
These results demonstrate that removal of occlusal force caused change in BAp crystallite alignment in the alveolar area in mandibular cortical bone. This indicates the importance of evaluating BAp crystallite alignment in addition to BMD in clinical practice. Moreover, clarification of BAp crystallite alignment in the jawbone would allow direction of occlusal load to be taken into account in orthodontic treatment involving tooth alignment.