LATERAL PTERYGOID MUSCLE FUNCTION/CONDYLAR GROWTH

临床与科研相结合培训的研究计划 该计划分为两个阶段。第一阶段，描述了 本提案中的详细内容，将在开始时启动 并将在获奖的03年前完成。vbl.使用 作为培训方案第二阶段基础的第一阶段研究 将回答一个或多个关于髁状突的具体问题 头两年的生长和肌肉适应能力 这项研究项目。 将在第一阶段解决的具体研究问题 关注(一)翼外侧肌和浅翼肌的作用 咬肌在下颌骨生长和适应中的作用 以及(Ii)发生在外侧的适应。 翼状突触后肌和咬肌浅层的反应 功能性下颌骨突出。实验室的老鼠将会是 用作实验动物。具体的假设将会 应解决的问题是：(I)功能性下颌前突导致 翼外肌的紧张性活动增强 以及(Ii)咬肌浅层，程度较轻 这种肌肉活动与髁突的增加有关。 成长。这项实验的具体目的是：(I) 观察翼外区和翼浅区的适应 咬肌对改变下颌位置的应用 定量形态和生理技术(即， 纤维长度的组织学分析，纤维的组织化学分析 类型和面积、刺激咬合力和收缩特性 分析)和(2)在以下范围内审查这些调查结果 下颌骨髁突内的形态变异 与软骨细胞增殖和软骨内膜有关 骨化(即，髁突生长和骨化的放射自显影分析) 下颌骨生长和形态的头影测量分析)。

The research plan for the combined clinical-research training program is organized into two phases. Phase I, which is described in detail in this proposal, will be initiated at the start of the award and will be completed by year 03 of the award. Using phase I research as a foundation, phase II of the training program will address one or more of the specific questions about condylar growth and muscle adaptation that arise from the first two years of the research project. The specific research problems that will be addressed in phase I concern (i) the role of the lateral pterygoid and superficial masseter muscles in the growth and adaptation of the mandibular condyle and (ii) the adaptations that occur within the lateral pterygoid and superficial masseter muscles in response to functional protrusion of the mandible. Laboratory rats will be used as experimental animals. The specific hypotheses that will be addressed are: (i) functional mandibular protrusion results in an increase in the tonic activity of the lateral pterygoid muscle and, to a lesser extent, the superficial masseter muscle and (ii) this muscle activity is associated with an increase in condylar growth. The specific purposes of the experiment are: (i) to examine adaptations within the lateral pterygoid and superficial masseter muscles to altered mandibular position using quantitative morphologic and physiologic techniques (i.e., histologic analysis of fiber length, histochemical analysis of fiber types and area, stimulated bite force, and contractile properties analysis) and (ii) to examine these findings within the context of morphologic variations that occur within the mandibular condyle related to cartilage cell proliferation and endochondral ossification (i.e., autoradiographic analysis of condylar growth and cephalometric analysis of mandibular growth and form).