CALCIFICATION MECHANISM OF THE OSTEOID IN THE PERIODONTAL LIGAMENT ON THE TENSION SIDE DURING TOOTH MOVEMENT.

采用不固定和不脱钙冰冻切片，对大鼠牙齿移动过程中牙周韧带类骨质(张力侧)进行元素分析(EPMA)和游离钙离子检测。采用放射自显影技术，观察大鼠上第一磨牙向类骨质中的摄取情况。制备未固定和未脱钙的磨牙牙周膜冰冻切片，进行组织学和组织化学(碱性磷酸酶活性：偶氮染料法)观察和EPMA检测。在测定游离钙时，大鼠在液氮冷冻固定前60s从心脏注射荧光游离钙指示剂Fluo-3；在放射自显影方面，在戊二醛灌流固定前60min腹内注射放射性核素。然后对上颌进行放射自显影。颊牙周…中的骨面更多的外侧韧带(张力侧)呈波浪形，形成大量类骨质。类骨质层和成骨细胞层有较强的碱性磷酸酶活性。骨样上的EPMA显示P和Ca的峰值非常高，随着分析部位远离骨骼边缘，P和Ca的峰值先急剧下降，然后逐渐下降。S和K在整个分析点上都保持了稳定的峰值。直线分析显示P和Ca的变化具有恒定的同步性。绿色荧光显示游离的Ca~(2+)和Ca~(2+)从整个牙周间隙和牙髓腔发出。类骨质的荧光强度大于牙周韧带的荧光强度。EPMA数据显示类骨质中钙的峰值高于牙周韧带中的峰值。注射后60min，类骨质中钙离子在颊牙周韧带(张力侧)深层沉积。结果表明，类骨质中磷和钙的浓度在钙化过程中升高，并且它们的浓度被精确地调节，钙由毛细血管供应，部分钙以离子的形式存在于类骨质中。较少

Elemental analysis (EPMA) and detection of free Ca^<2+> were performed in the osteoid of the periodontal ligament (tension side) during the tooth movement in rats, using unfixed and undecalcified frozen sections. The uptake of Ca^<45> into the osteoid was examined by autoradiography.Upper first molars of mature male rats were moved seven days, and the upper jaws were fixed in liquid nitrogen. The unfixed and undecalcified frozen sections of the molar periodontal ligament were prepared for histological and histochemical (alkaline phosphatase activity : azo-dye method) observation and also for EPMA.In the detection of free-Ca, fluo-3, a fluorescent free Ca indicator, was injected from the hearts of the rats 60 sec.before freeze fixation by liquid nitrogen.In regard to the Autoradiography, Ca^<45> radioisotope was also injected intraperitoneally 60 min.before perfusion fixation of glutaraldehyde. Then the upper jaws were processed for Autoradiography.A bone surface in the buccal periodont … More al ligament (tension side) showed a wavy configuration, and a considerable amount of osteoid was formed. Intense ALP ase activity was noticed in the osteoid and osteoblastic layr. EPMA on the osteoid revealed extremely high peaks of P and Ca, that dropped a bruptly at first and then declined gradually, as the analyzed site moved away from the edge of the bone. S and K maintained steady peaks throughout the whole analyzed sites. Line analyzes demonstrated constant synchronization for the changes of P and Ca.Green fluorescence, showing the presence free Ca^<2+>, was emitted from the whole periodontal space and pulp cavity. The fluorescence from the osteoid was more intense than that from the periodontal ligament. EPMA data showed higher peak of Ca in the osteoid than in the periodontal ligament.Ca^<45> was deposited deeply in the osteoid of the buccal periodontal ligament (tension side) in 60 min.after the peritoneal injection.These results indicate that the osteoid concentration of P and Ca is elevated in the calcification and their concentration regulated precisely, and also that the Ca was supplied from the capillary, some of which is present in the form of ion in the osteoid. Less