Huja Sarandeep S, Fernandez Soledad A, Hill Kara J, Li Yan
Section of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio 43210, USA.
Anat Rec A Discov Mol Cell Evol Biol. 2006 Dec;288(12):1243-9. doi: 10.1002/ar.a.20396.
Bone turnover rates can be altered by metabolic and mechanical demands. Due to the difference in the pattern of loading, we hypothesized that there are differences in bone remodeling rates between the maxillary and mandibular alveolar processes. Furthermore, in a canine model, the alveolar process of teeth that lack contact (e.g., second premolars) would have a different turnover rate than bone supporting teeth with functional contact (e.g., first molars). Six skeletally mature male dogs were given a pair of calcein labels. After sacrifice, specimens representing the anterior and posterior locations of both jaws were prepared for examination by histomorphometric methods to evaluate the bone volume/total volume (BV/TV; %), bone volume (mm2), mineral apposition rate (MAR; microm/day), and bone formation rate (BFR; %/year) in the alveolar process. There were no significant differences (P>0.05) in the BV/TV within the jaws. The bone volume within the alveolar process of the mandible was 2.8-fold greater than in the maxilla. The MAR was not significantly different between the jaws and anteroposterior locations. However, the BFR was significantly (P<0.0001) greater in the mandible than in the maxilla. The anterior location had higher (P=0.002) remodeling than the posterior location in the maxilla but not in the mandible. While there was a greater bone mass and increased remodeling in the mandible, no remodeling gradient in the coronal-apical direction was apparent in the alveolar process. Bone adaptation probably involves a complex interplay of bone turnover, mass, and architecture.
骨转换率可因代谢和机械需求而改变。由于负荷模式的差异，我们推测上颌和下颌牙槽突的骨重塑率存在差异。此外，在犬类模型中，缺乏接触的牙齿（如第二前磨牙）的牙槽突与具有功能性接触的牙齿（如第一磨牙）的牙槽突相比，其转换率会有所不同。对六只骨骼成熟的雄性犬给予一对钙黄绿素标记。处死后，制备代表上下颌前后位置的标本，通过组织形态计量学方法进行检查，以评估牙槽突的骨体积/总体积（BV/TV；%）、骨体积（mm²）、矿物质沉积率（MAR；微米/天）和骨形成率（BFR；%/年）。颌骨内的BV/TV无显著差异（P>0.05）。下颌牙槽突内的骨体积比上颌大2.8倍。颌骨之间以及前后位置之间的MAR无显著差异。然而，下颌的BFR显著高于上颌（P<0.0001）。上颌前部的重塑高于后部（P=0.002），而下颌则不然。虽然下颌的骨量更大且重塑增加，但在牙槽突中未观察到明显的冠-根方向的重塑梯度。骨适应性可能涉及骨转换、骨量和骨结构的复杂相互作用。
