充填方式对种植义齿固定螺丝孔粘接强度及密封性的影响研究

 目的　研究不同充填方式封闭种植义齿固定螺丝孔对粘接强度及密封性的影响。方法　制作上颌第一前磨牙种植螺丝固位氧化锆冠试件80件，按照粘接前是否喷砂预处理、充填树脂种类、充填深度随机均分为8组，分别置于墨水溶液7 d，万能材料实验机上对螺丝孔内树脂充填体进行推出测试，记录树脂充填体脱粘接时的瞬间载荷，并取出树脂充填体，显微镜下观察记录并比较充填体染色的范围。结果    是否喷砂及树脂种类对粘接强度的影响均具有统计学意义（P < 0.01）；充填体厚度会显著影响粘接断裂载荷大小（P < 0.01），但对粘接强度的影响无统计学意义（P = 0.09）。喷砂后使用3 mm流动树脂充填微渗漏最少，不喷砂使用2 mm膏状树脂微渗漏最严重，是否喷砂、树脂种类及充填体厚度均对微渗漏有显著影响（P < 0.05）。结论    固定螺丝孔表面喷砂处理可增加粘接强度，减少微渗漏。流动树脂封闭种植义齿固定螺丝孔可获得相似的密封性及高于普通膏状树脂的粘接强度。在一定范围内，增加充填体厚度有助于提高固定螺丝孔封闭树脂的咬合承受力并减少微渗漏。

The clinical study on fluoride thermoplastic resin for preventing dental caries in abutment teeth of removable partial dentures

The clinical study on fluoride thermoplastic resin for preventing dental caries in abutment teeth of removable partial dentures. YANG Jun，ZHU Hong-shui，GUO Jing. Nanchang University Affiliated Oral Hospital， Nanchang 330006， ChinaAbstract： Objective To study the effect of the removable topical-fluoride denture base to prevent dental caries in abutment teeth. Methods A total of 24 defect of dentition patients were selected and randomly divided into control group and experimental group. Subjects in the control group weared fluoride self-curing resin RPDs including CaF2， and subjects in the experimental group weared fluoride thermoplastic resin RPDs including CaF2. Fluoride ion-specific electrode was used to measure the fluoride concentration in dental plaque and saliva before， and one week，two weeks，three weeks，four weeks after subjects weared RPDs. Results The fluoride concentration in saliva was not raised significantly in each group. In the control group and experimental group， compared with the fluoride concentration in plaque which was collected from the teeth away from abutment teeth， fluoride concentration in plaque which was collected from the abutment teeth was higher （P＜0.05）. Compared with the control group， fluoride concentration in plaque did not change significantly in the experimental group（P＞0.05）. Conclusion The fluoride thermoplastic resin can release fluoride ion continually and prevent dental caries in abutment teeth of removable partial dentures.