摘要目的 评价牙冠延长术在牙体缺损达龈下的前牙修复中的临床美学效果.方法 对28例患者54颗牙体缺损达龈下1.5～4.0 mm的前牙行牙冠延长术,按术前断端位于龈下的最深距离分为A组(＜3 mm)和B组(3～4 mm),术后8周烤瓷桩冠修复,分别记录和比较患牙手术前后的菌斑指数(PLI)、出血指数(SBI)、缺损最深位点处的探诊深度(PD)和松动度(MD),观察牙周情况和牙齿保存修复效果.结果 两组患牙术后不同时期的PLI、SBI、PD均明显优于术前(P＜0.01).修复后1年A、B两组成功率分别为96.8%和69.6%,差异有统计学意义(P＜0.01).术前及修复后1年的松动度,A组病例各牙之间差异无统计学意义(P＞0.05);B组病例修复后1年MD较术前改善,各牙之间差异具有统计学意义(P＜0.01)及相关性.结论 牙冠延长术有利于牙体缺损达龈下患牙的保存,能获得较好的美学效果.成功与否受多种因素的影响,适应证的选择是一个重要方面.

abstractsObjective To observe the results of crown lengthening surgery on the teeth with subgingival defect.Methods Crown lengthening surgery was performed on 54 terior teeth,which were divided into two groups based on probing depth of pre-operation:group A (<3 mm) and group B (3-4 mm).All teeth were restored 8 weeks after operation and followed-up to 1 year.The parameters of plaque index (PLI),suleus bleeding index (SBI),maximal defect probing depth (PD) and mobility degree (MD) at different times were measured,respectively.Results PLI,BI and PD were significantly improved during the follow-up period (P<0.01).The success rates of both groups were 96.8% and 69.6%, respectively (P<0.01).No significant difference about MD in the group A one year after restoration (P>0.05),but a significant improvement in the group B (P<0.01).Conclusion Crown lengthening surgery is a good method on the teeth with subgingival defect,but one must select the right indication.