Objective: Using type X collagen as a marker, this research was designed to examine the alteration of condylar growth in response to mandibular condylar forward positioning. Methods: One hundred female Sprague-Dawley rats with 5 weeks of age were randomly divided into five experimental and five control groups. In the experimental groups, bite jumping appliances created forward positioning of the condyle. The experimental rats, together with the age-matched controls, were sacrificed on days 3, 7, 14, 21 and 30, respectively. Tissue sections were cut in the sagittal plane through the mandibular condyle and were processed for in situ hybridization and immunostaining of type X collagen and then for quantitative imaging analyses. Results: (1) Both type X collagen mRNA in situ hybridization signals and type X collagen immunostaining were localized within the hypertrophic zone of the condylar cartilage. (2) With condylar forward positioning, the level of type X collagen mRNA signals (8541±74 μm2 at peak) was 300% higher than that in the controls (2117±78 μm2 at peak); type X collagen immunostaining in condylar advancing groups (54864±134 μm2 at peak) was 254% more than that in the controls (15470±121 μm2 at peak). (3) The amount of type X collagen mRNA signals and immunostaining in experimental and control groups reached the highest levels at day 14 and day 21, respectively, indicating that an increase in endochondral ossification occurred 21 days after condylar forward deviation. Conclusion: Condylar forward repositioning provokes an enhanced maturation of condylar chondrocytes resulting in increased synthesis of type X collagen, a extracellular protein that attributes to endochondral ossification.

将羟基磷灰石（HA）涂层钛种植体延期植入狗颌骨，施以150g的正畸力，通过口内及X线照片测量，动态研究种植支抗在3个月内的稳定性。结果显示：判断种植支抗的移动应综合采用口内及通过X线照片测量两种方法；HA涂层钛种植支抗的骨内段无移位（P＞0.05），而基桩在受力后第2和第3个月倾斜移动。说明该类骨内种植体的体部承受正畸力时具有良好的稳定性，在将其颈部设计调整后作为种植支抗，可保证在短期正畸治疗时间内不移动。

目的探讨成都地区青少年牙弓后段可利用间隙的增龄性变化，为临床应用全牙弓间隙分析提供依据。方法将1999-2000年在原华西医科大学口腔医院正畸科就诊的11-20岁初诊患者，按纳人和排除标准筛选，共获得526例，其中男232例，女294例。按领骨的矢状向、垂直向异常分类，通过头影测量分析获得牙弓后段可利用间隙量。分析成都地区青少年牙弓后段可利用间隙增龄性变化规律，用多变量相关分析检测牙弓后段间隙量与年龄、性别、安氏错抬类型、垂直骨面型的相关性。结果（1）下领牙弓后段间隙量与年龄、安氏错抬类型相关。（2）男女性的下领牙弓后段可利用间隙增龄性变化曲线有一定差异。（3）骨性U1类患者的牙弓后段可利用间隙增龄性变化量明显大于安氏IIU类患者。结论成都地区青少年的数值同国外数值差异较大，提示在进行全牙弓间隙分析时，应考虑种族的差异及错抬类型。

目的：探讨用功能矫治器（FR-I）矫治安氏Ⅱ类1分类错、矫治前后舌的形态、位置和舌骨位置的变化。方法：通过X线头影测量，分析个体治疗前后的变化。结果：治疗后舌体形态有改变，随着口腔功能间隙增大，舌体在口腔内充盈度增大，舌位置有前移趋势，舌尖位置靠前。舌骨位置在水平向前移，垂直向下降。结论：进一步证实FR-l矫治器矫冶安氏Ⅱ类1分类错原理之一是引导下颌向前，同时使舌体及颈部软组织向前改建，改善矢状不调的颌骨关系；同时矫治使口腔功能间隙增大，舌的形态随之改变，达到矫治下颌发育不足的Ⅱ类错畸形的目的。