MECHANICAL ENVIRONMENT IN MANDIBULAR DISTRACTION

下颌牵引的机械环境

• 批准号: 6620346
• 负责人: SUSAN W HERRING
• 金额: $ 22.74万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6620346
• 关键词: biomechanics; cardiovascular system; gene expression; immunocytochemistry; juvenile animal; mandible /maxilla; mandibular condyle; mastication; miniature swine; muscle function; muscle proteins; osteogenesis; osteogenesis imperfecta; periosteums; radiography; stainings; temporomandibular joint syndrome; tissue /cell culture; ultrasonography

DESCRIPTION (provided by applicant): Distraction osteogenesis (DO) is a means to elongate bone by placing tensile loads on a healing osteotomy. Although DO has been used on the mandible for only a decade, the technique is already supplanting more traditional orthognathic procedures, especially for children. Despite the fact that DO uses mechanics to accomplish its goals, the actual mechanical environment is unknown. Functions such as mastication must place intermittent compressive or shearing strains on the distraction site. These strains, as well as the tensile strains produced by the distraction appliance, are of critical biological significance for the osteogenic process, but have never been measured. Using a well-established model for mandibular DO, the pig, we propose (Aim 1) to clarify the mechanical environment of the distraction site at the time of osteotomy, during distraction, and during consolidation by making direct measurements of strain using strain gages, digital ultrasonics and differential variable reluctance transducers. These studies will investigate the influence of appliance size, stability, and placement as well as the action of specific muscles and occlusal loads. Further, we will address a major concern of treating growing children by mandibular DO, whether the procedure adversely affects growth at the mandibular condylar by overloading the TMJ. Thus, we propose (Aim 2) to ascertain the impact of DO on TMJ mechanics and growth by performing strain gage measurements on the condylar neck and relating the findings to growth, as measured by mineral apposition rate and periosteal deformation. The mechanical environment of DO, particularly the stability of the distraction site, may affect the course of healing and the final result by influencing which cells are recruited, the rapidity with which they proliferate, and their eventual fate. Therefore, we propose (Aim 3) to relate the mechanical history of DO to the repair process by assessing the contributions of the periosteum, muscle connective tissue, and vascular system to the regenerate. This will be accomplished by pulse labeling of replicating cells during distraction, combined with an investigation of protein expression at the time of sacrifice. The most important contributions of this proposal will be the characterization of strain at the DO site under natural conditions, and the application of that information to understanding of how DO works on a cellular level and how it affects mandibular growth.

描述（由申请人提供）：分散骨化（DO）是一种手段 通过在愈合截骨术上施加拉伸负荷来拉长骨头。虽然做 已在下颌骨上使用了十年，该技术已经是 取代更传统的矫形程序，尤其是对于儿童。 尽管确实使用力学来实现其目标，但实际 机械环境未知。必须放置诸如咀嚼之类的功能 干扰部位上的间歇性压缩或剪切应变。这些 菌株以及分散设备产生的拉伸菌株， 对于成骨过程具有至关重要的生物学意义，但具有 从未测量过。使用公认的下颌DO模型，猪， 我们建议（目标1）阐明分心的机械环境 截骨时，分散注意力和在整合期间的位置 使用应变计，数字超声处理直接测量应变 和差异可变不情愿传感器。这些研究会 还研究设备尺寸，稳定性和放置的影响 作为特定肌肉和咬合负荷的作用。此外，我们将解决 通过下颌骨治疗成长子女的主要关注点，是否 程序通过超负荷对下颌con的生长产生不利影响 TMJ。因此，我们建议（AIM 2）确定DO对TMJ的影响 力学和生长通过在do中进行应变计测量 颈部并将发现与生长有关 速率和骨膜变形。 DO的机械环境，特别是 分心站点的稳定性可能会影响康复的过程 通过影响哪些细胞招募的最终结果，其速度的速度 他们扩散，最终的命运。因此，我们建议（目标3） 通过评估修复过程的机械历史与维修过程相关联 骨膜，肌肉结缔组织和血管系统的贡献 再生。这将通过复制的脉冲标记来完成 分心期间细胞与蛋白质表达的研究结合 在牺牲时。该提案的最重要贡献 将是在自然条件下DO位点的菌株的表征， 以及将这些信息应用于理解如何工作的 细胞水平及其影响下颌生长。