Esashika Mayumi, Kaneko Sawa, Yanagishita Masaki, Soma Kunimichi
Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
J Med Dent Sci. 2003 Jun;50(2):183-94.
During orthodontic treatment, it is often necessary to move the hypofunctional teeth. In this study, we revealed an influence of orthodontic forces in the hypofunctional periodontal ligament, and focused on the distribution of proteoglycans, major extracellular matrix molecules. Five-week-old rats were divided into normal group and hypofunctional group. To induce occlusal hypofunction, occluding teeth of the mandibular first molar were extracted. At 8-week-old, orthodontic force by 15 or 2 gf titanium-nickel alloy closed coil spring was applied to the mandibular first molar toward the mesial direction. Immunohistochemical analysis was performed using antibodies for chondroitin sulfate (CS) and heparan sulfate (HS). In normal group, CS was observed throughout the extracellular matrix, while HS was observed on the endothelial cells and the osteoclastic cells on compressive side. In hypofunctional group without orthodontic appliance, CS and HS were detected in less amounts. With 15 gf, CS was observed at the compressive area where no cells and fibers were present, and HS was observed at the periphery of this area. With 2 gf, however, the distribution of CS and HS was similar to the normal control. These findings indicate that CS and HS were affected by orthodontic forces, and suggest their distinct functions in tissue remodeling.
在正畸治疗过程中，通常需要移动功能低下的牙齿。在本研究中，我们揭示了正畸力对功能低下的牙周韧带的影响，并聚焦于蛋白聚糖（主要的细胞外基质分子）的分布。将5周龄的大鼠分为正常组和功能低下组。为诱导咬合功能低下，拔除下颌第一磨牙的对合牙。8周龄时，用15或2 gf的钛镍合金闭合螺旋弹簧向近中方向对下颌第一磨牙施加正畸力。使用硫酸软骨素（CS）和硫酸乙酰肝素（HS）抗体进行免疫组织化学分析。在正常组中，CS在整个细胞外基质中均有观察到，而HS在内皮细胞和受压侧的破骨细胞上有观察到。在未佩戴正畸矫治器的功能低下组中，CS和HS的检测量较少。施加15 gf力时，在无细胞和纤维的受压区域观察到CS，在该区域的周边观察到HS。然而，施加2 gf力时，CS和HS的分布与正常对照组相似。这些发现表明CS和HS受正畸力影响，并提示它们在组织重塑中具有不同的功能。
