聚乳酸-羟基乙酸-辛伐他汀对拔牙术后剩余牙槽嵴吸收影响的实验研究

目的探讨聚乳酸-羟基乙酸(PLGA)复合辛伐他汀对剩余牙槽嵴吸收的预防作用。方法选用60只Wistar雄性大鼠,随机分为实验组和对照组各30只,拔除右下中切牙后,实验组即刻植入PLGA-辛伐他汀支架材料,对照组植入PLGA支架材料。术后7、14、28、56、84d分别处死实验组和对照组大鼠各6只,用软X线、骨密度、测量组织学等方法进行药效评价。结果剩余牙槽嵴相对长度:术后14、28、56、84d对照组比实验组[(0·997±0·007)、(0·965±0·139)、(0·996±0·021)、(0·960±0·026)]明显降低,差异有统计学意义(P<0·05)。牙槽骨骨密度:术后28、56、84d实验组[(7·101±0·025)、(7·178±0·039)、(7·162±0·052)g/cm2]与对照组[(7·074±0·014)、(7·117±0·012)、(7·059±0·037)g/cm2]相比明显升高,差异有统计学意义(P<0·05)。组织学观察显示实验组成骨速度和质量优于对照组。结论以PLGA为载体局部应用辛伐他汀可诱导拔牙窝内骨形成,保存了剩余牙槽嵴的长度和骨量。

Effect of simvastatin on residual ridge resorption after tooth extraction

OBJECTIVE: To observe the effect of simvastatin carried by poly (lactide-co-glycolide) (PLGA) on residual ridge resorption following tooth extraction. METHODS: Sixty male Wistar rats were divided into experimental groups and control groups (30 rats/group). PLGA was immediately implanted with or without simvastatin into extraction sockets of the mandibular incisors. Soft X-ray photography, bone mineral density (BMD) and histopathologic study were conducted at 7, 14, 28, 56, and 84 days after implantation. RESULTS: The relative length values of residual alveolar ridge of the experimental groups were greater than those of the controls at 14, 28, 56, and 84 days after implantation, and there was a significant difference between the experimental and control groups (P < 0.05). The BMD of the specific region was higher in the experimental groups [(7.101 +/- 0.025), (7.178 +/- 0.039), and (7.162 +/- 0.052) g/cm(2)] than that in the control groups [(7.074 +/- 0.014), (7.117 +/- 0.012), and (7.059 +/- 0.037) g/cm(2)] (P < 0.05) after 28, 56, and 84 days. Light microscopy showed that bone formation rate and quality of the experimental group were better than those in the control group at the same time. CONCLUSIONS: Simvastatin carried by PLGA could induce bone formation of tooth socket. Local application of simvastatin would be potential to preserve the length and bone volume of alveolar ridge after tooth extraction.