摘要
目的:分析不同固位型设计对粘结桥固位的影响。方法:将45个铸造金属基牙后牙粘结桥模型试件,按固位设计分为基本固位C型组(对照组)、轴沟组和针道组,每组15个。分别测量粘结桥试件用PanaviaF粘固24h后未疲劳和经过24万次、120万次模拟咀嚼疲劳后的最大向固位力。结果:未经疲劳时,对照组最大固位力值(566.82±71.59N)<轴沟组(656.07±137.29N)<针道组(791.40±141.22N)。疲劳24万次后,对照组最大固位力值(539.37±88.26N)<轴沟组(599.19±82.38N)<针道组(710.98±165.73N)。疲劳120万次后,轴沟组最大固位力值(307.93±46.09N)<对照组(365.79±61.78N)<针道组(505.04±125.53N)。3种固位型之间以及经过不同咀嚼疲劳次数的同一固位型粘接桥最大固位力之间差异均有统计学意义(P<0.001)。在控制疲劳次数因素后,针道组固位力均大于轴沟组和对照组(P<0.05),轴沟组和对照组之间差别无统计学意义(P>0.05)。经过120万次模拟咀嚼疲劳后不同固位型设计粘结桥的固位力均显著降低(P<0.001)。结论:与轴沟相比,针道辅助固位型可更有效地提高粘结桥的固位力。
Objective： To evaluate the influence of retention-form design of resin bonded fixed partial dentures（RBFPDs）. Methods： Forty-five metal replicas of posterior metal RBFPDs were divided into 3 groups（ n = 15 ） ：C shape（ control group） , C shape ± axial groove, C shape ± pin hole. All the replicas were luted with Panavia 17 cement and subgroup of 5 specimens were subject to 70 N compressive load cy- cling for 0 cycles, 240 000 cycles , and 1 200 000 cycles respectively. Half of the cycles was on the cen- tral fossa of the pontics and half on the buccal inclined surface of the lingual cusp. Forces for dislodgment of the specimens were applied along the long axis of the abutment at a crosshead speed of 1.0 mm/rain. The separation forces were recorded as maxium retention force at the time of dislodgement. Results： Se- paration forces of the C shape group （566.82 ±71.59 N） 〈 axial groove group（656.07 ± 137.29 N） 〈 C shape ± pin hole group （791.40 ± 141.22 N） without compress load cycling. After 240 000 cycles, C shape group （539.37 ± 88.26 N） 〈 axial groove group （599.19 ± 82.38 N） 〈 C shape ± pin hole group （710.98 ± 165.73 N）. After 1 200 000 cycles, axial groove group（307.93 ±46.09 N） 〈 C shape group （365.79 ±61.78 N） 〈 C shape ± pin hole group （505.04 ± 125.53 N）. The mean retention force was related to the design of the retention force and the fatigue cycles（P 〈0. 001 ）. When the fa- tigue cycles factor was controlled , separation force of the C shape ± pin hole was greater than C shape ± axial groove group and C shape group（P 〈0.05）. The difference of C shape ＋ axial groove group and C shape group was not significant （P 〉 0.05 ）. After 1 200 000 cycles, the retention force of the RBFPDs decreased significantly （P 〈0.001 ）. Conclusion： To compare with axial groove, the design of pinhole retention form was conduced to the improvement of the retention force and durability of RBFPDs.
出处
《北京大学学报（医学版）》
CAS
CSCD
北大核心
2008年第1期80-82,共3页
Journal of Peking University:Health Sciences
关键词
牙黏合
牙修复体固位
牙钉
Dental bonding
Dental prosthesis retention
Dental pins
