阵列光纤牙齿颜色测量系统研究

介绍了阵列光纤牙齿颜色测量系统的组成和工作原理,该系统由微型光谱仪、光纤探头、CCD探测器和计算机组成。它能够对牙齿不同部位的颜色进行快速、准确、方便的测量。为解决目前临床牙齿测配色不准确问题,提供了一种可行的新方法,为真假牙齿比色以及新的口腔材料的研制开发提供了依据和检测手段,在镶牙及活体牙颜色测量方面具有重要意义。该系统还可用于其他需要进行颜色测量的场合。     

Influence of abutment material on the stress of implant-supported all-ceramic single crown

In order to investigate the influence of abutment material on the stress of implant-supported all-ceramic single crown, a 3D finite element model of implant-supported mandibular first premolar was computed by COSMOS/M 2.85 software. Alumina, zirconia, and titanium were used as abutment materials respectively. Vertical 600 N and horizontal 225 N load was applied on the occlusal surface. The results show that the stress distribution of implant-supported single crown was similar for different abutment materials. Maximum stresses within the crown were higher when titanium abutment was used. Maximum stress of titanium abutment was lower than that of ceramic abutment. Within the screw and fixture, maximum stresses had no difference under vertical loading but higher as titanium abutment was used under horizontal loading. There was no difference of maximum stress within the bone when different abutment materials were used. The present findings indicate that the abutment material had no influence on the stress distribution of implant-supported all-ceramic single crown but maximum stress when the titanium abutment was lower than that of ceramic abutment.     

口腔黏膜微区反射光谱特性的分析

介绍了光纤探头式口腔黏膜反射光谱检测系统。该系统由微型光谱仪、光纤探头、CCD探测器和计算机组成。口腔黏膜反射光谱检测仪可用来对正常口腔黏膜和病变口腔黏膜进行快速对比测量，经过数据分析为医生对口腔黏膜病的诊断及治疗提供科学的依据。利用该测量系统，分析了病变口腔黏膜与正常口腔黏膜反射光谱，提出了实现客观诊断口腔黏膜病的方法。     

Influence of different luting agents on the stress distributions of implant-supported all-ceramic single crown

The purpose of this study was to investigate the influence of different luting agents on the stress distribution within the crown, abutment and peri-implant bone of implant-supported all-ceramic single crown. A three-dimensional finite element model of an implant-supported single crown for the first premolar of mandible was created by COSMOS 2.85. Resin-modified glass ionomer and two different resin adhesives were used to cement the crown and abutment. Vertical 600 N and horizontal 225 N loads were applied to stimulate the condition of chewing. The stress distributions within the all-ceramic crown, abutment and peri-implant bone were analyzed. The experimental results show that the stress distributions of all-ceramic crown, abutment, implant and peri-implant bone were similar when different luting agents were used. The result of present study indicated that luting agents had no influence on the stress distributions of implant-supported all-ceramic single crown.