雌激素替代疗法对骨质疏松实验性牙周炎大鼠牙槽骨吸收的影响

The impact of estrogen replacement therapy upon alveolar bone absorption in osteoporosis rats with experimental periodontitis

目的:通过建立大鼠骨质疏松模型,研究雌激素替代治疗对实验性牙周炎大鼠牙槽骨高度的影响。方法:26只雌性SD大鼠随机分为3组,Sham组(n=9):假手术;OVX组(n=9):卵巢切除;OVX+E2组(n=8):卵巢切除加雌激素治疗。大鼠适应性喂养7 d后行假手术或双侧卵巢切除术,OVX+E2组于术后第2天起皮下注射苯甲酸雌二醇,剂量为每次20μg/kg体重,3 d 1次。卵巢切除术或假手术后28 d结扎丝结扎上颌第一磨牙牙颈部诱导牙周炎,第63天处死动物,常规取材,测量上颌第一磨牙PBL,摄上颌骨X线片,测量上颌第一磨牙PBS。结果:Sham组、OVX组和OVX+E2组的PBL值分别为0.276±0.011,0.472±0.014和0.286±0.010;PBS值分别为44.040±1.966,38.009±7.062和45.626±2.231。采用完全随机设计单因素方差分析,上颌第一磨牙OVX组PBL高于Sham组和OVX+E2组,OVX组PBS低于Sham组和OVX+E2组,均P<0.05。Sham组和OVX+E2组的PBL、PBS间差异无统计学意义,P>0.05。结论:雌激素缺乏促进实验性牙周炎大鼠牙槽骨吸收,雌激素替代治疗可有效预防因此产生的牙槽骨高度降低,降低失牙风险。

Objective： To evaluate the effects of estrogen replacement therapy upon alveolar bone height in rats with experimental periodontitis via establishing osteoporosis rats model. Methods： Twenty - six female SD rats were randomly divided into three groups, group Sham （n=9）： Sham operated; group OVX （n=9）： ovariectomized; group OVX＋EE（n=8）： ovariectomized and estrogen administrated. All of the rats were fed 7 days to adapt the environment before ovariectomy or Sham operation. In group OVX ＋E2 20μg/kg benzyl estradiol were injected subcutaneously every three days, the dose was depending on weight. Twenty-eight days later, the upper first molars were placed ligature to induce periodontitis. On the 63th day, the animals were sacrificed and the specimens were routinely processed. The periodontal bone loss and periodontal bone support were measured on digit photos of the maxillar and X-ray respectively. Results： The PBL of group Sham, group OVX and group OVX＋E2 were 0.276±0.011,0.472±0.014 and 0.286±0.010 respectively, the PBS were 44.040±1.966,38.009±7.062 and 45.626±2.231 respectively. The PBL and PBS were analyzed by the one-way analysis of variance. The analysis revealed that the PBL of group OVX was higher than that of the other groups, and the PBS was lower. Comparing PBL and PBS, there were no difference between group Sham and group OVX ＋E2. Conclusion： Estrogen-deficient state significantlyincreased alveolar bone absorption in rats with experimental periodontitis, and such an effect can beprevented by estrogen administration.