【摘要】 目的探讨牙体预备中不同聚合度的沟固位形和洞固位形对增加修复体固位效果的影响。方法选取本院2012年1~8月的65例患者的75颗牙冠短小磨牙作为研究对象,分别进行15颗常规牙体预备修复、30颗增加沟固位形和30颗增加洞固位形全冠修复,其中沟固位形又分为两组,每组15颗,分别在近远中邻面中央制备外展度数为0°和6°的沟固位形;同样洞固位形也分为两组,每组15颗,分别在合面中央预备出外展度数为0°和6°的洞固位形,常规制作全冠,比较各组修复体的脱落情况。结果常规修复组脱落5颗,6°洞固位形组中脱落1颗,6°沟固位形组中脱落3颗,0°沟固位形组中脱落1颗。0°和6°洞固位形组、0°和6°沟固位形组的脱落率显著低于常规修复组,差异有统计学意义(P<0.05)。0°和6°洞固位形组的脱落率比较,差异无统计学意义(P>0.05)。0°和6°沟固位形组的脱落率比较,差异有统计学意义(P<0.05)。辅助固位形组的边缘密合度显著优于常规修复组,差异有统计学意义(P<0.05)。结论临床牙体预备中增加洞、沟辅助固位形,可以增加修复体的固位效果,减少修复失败率。更多还原

【Abstract】 Objective To explore the influence of different degree of polymerization of groove shape retention and hole shape retention on the increasing retention effect of restoration in the tooth preparation. Methods 75 dental crowns with short molars of 65 patients from January 2012 to August in our hospital were selected as the research group,15 teeth were given routine repair tooth preparation,30 teeth were given increasing the groove shape retention,30 teeth were given increasing the hole shape retention of complete coronal restoration.The groove shape retention group was divided into the two groups and 15 teeth in each group,which was respectively conducted the groove shape retention of outreach degree with 0 angle and 6 angle nearly the central of distal proximal surface.The retention hole shape was also divided into the two groups and 15 teeth in each group,which was respectively conducted the retention hole shape of outreach degree with 0 angle and 6 angle in the surface of the central.The complete crown were made in routine and loss situation of restoration was compared in the different groups. Results In the conventional repair group,there were 5teeth off,in the 6 angle retention hole shape group,1 tooth was fell off,in the 6 angle retention groove shape group,3teeth were fell off,in the 0 angle retention groove shape group,1 tooth was fell off.The rate of fall-off in 0 angle and 6angle retention hole shape group,0 angle and 6 angle groove shape retention group was lower than that in the routine repair tooth preparation group,with significant difference(P<0.05).There was no significant difference in the rate of falloff between 0 angle and 6 angle hole shape retention group(P>0.05).There was significant difference in the rate of falloff between 0 angle and 6 angle groove shape retention group(P<0.05).The marginal density of the assist shape retention group was better than that of the conventional repair group,with significant difference(P <0.05). Conclusion Increasing hole and groove assist shape retention in clinical tooth preparation can improve the retention effect of restoration and reduce repair failure rate.更多还原