雌激素缺乏对大鼠牙槽骨吸收影响的实验研究

The experimental study of the impact of estrogen-deficient npon alveolar bone loss in rats

目的观察雌激素缺乏对大鼠牙槽骨吸收的影响。方法34只雌性SD大鼠随机分为4组。第1组假手术(n=8),第2组卵巢切除(n=9),第3组卵巢切除加牙周结扎(n=9),第4组卵巢切除、牙周结扎加雌激素治疗(n=8)。适应性喂养7天后行假手术或双侧卵巢切除术。第4组于术后第二天起皮下注射苯甲酸雌二醇．20μg／kg体重／次,三天一次。第3、4两组于卵巢切除术后28天,结扎丝结扎上颌第一磨牙诱导牙周炎。第63天处死全部大鼠。常规取材。观察牙用组织组织学改变。测量牙用骨丧失值(PBL)。比较牙用骨支持率(PBS)。检测血清碱性磷酸酶(ALP)。结果采用成组f检验,第1、2两组的PBL分别为0．398±O．147mm,0．663±0．132哪。PBS分别为O．588±O．058。0．440±0．197,组间差异均有统计学意义(P<0．05);第2、3两组的PBL、PBS组间差异均有统计学意义(P<0．05)。第3组的PBL为0．875±0．197mm,PBS为0．336±O．087;第3、4两组的PBL、PBS组间差别没有统计学意义(P>0．05),第4组的PBL为O．823±0．119mm,PBS为0．360±0．950。结论雌激素缺乏促进牙槽骨吸收,茵斑刺激加剧骨质疏松大鼠牙槽骨的吸收,雌激素替代治疗不能预防骨质疏松大鼠因茵斑刺激引发的牙槽骨吸收。

Objective To evaluate the impact of estrogen - deficient upon alveolar bone loss. Methods Thirty - four female SD rats were divided into four groups,group 1（n = 8） ： sham operated; group 2（n = 9） ： ovariectomized; group 3（n = 9） ： ovariectomized and ligated; group 4（n = 8） ： ovariectomized, ligated and estrogen administrated. All of the rats were fed 7 days to adapt the environment. Twenty - eight days after ovariectomy, the upper first molars of group 3 and group 4 were placed ligature to induce periodontitis. On the 63^th day, the animals were sacrificed and the specimens were routinely processed. The histological changes of periodontal tissues were observed, the periodontal bone loss and periodontal bone support were measured. In addition, serum levels of alkaline phosphatase were assessed. Results The PBL,PBS and ALP of group1 - group2, group2 - group3, group3 - group4 were analyzed by the t - test for two independent＇samples. The analysis revealed that an estrogen - deficient state significantly increased bone loss in rats, the ligature increased bone loss in osteoporotic rats, and such an effect could not be prevented by estrogen administration. Serum analysis demonstrated a higher bone turnover for the animals with estrogen deficiency, and estrogen therapy restored bone metabolism. Conclusion Estrogen deficiency may be one of the factors accelerating the progression of periodontitis in postmenopausal osteoporosis females and estrogen administration could not prevent the alveolar bone loss associated with a response to a plaque - related inflammatory process.