In vivo Investigation of Disintegration Mechanism of Ceramic Inlays.

由长方体瓷系统（G-Cera Cosmotech II，GC Co.，东京，日本）8年后进行体内评价。在25名患者中共放置了45个烧制陶瓷嵌体，并在放置时以及放置后6个月和1年，2年，4年，6年和8年时使用改良的U.S.P.H.S.标准对所有嵌体进行评价。用扫描电镜（SEM）观察修复体边缘区的降解和磨损情况。8年时，在82%的烧制陶瓷嵌体修复体中观察到了寿命（Kaplan-Meier方法）。边缘骨折11例（22%），包括大块骨折5例（11%）。边缘变色和复发性龋分别观察到14（31%）和3（7%）的prefications。扫描电镜观察显示，77%的修复体边缘微裂，36%的修复体磨损， ...更多信息 8年时74%的耳缘沿着有树脂粘固剂。磨牙和前磨牙之间这三个特征的发生率没有显著差异（Mann-Whitney检验，p<0.05）。8年的纵向临床观察表明，烧成陶瓷嵌体修复在临床上是可以接受的，但陶瓷嵌体的边缘崩解是一个亟待解决的问题，因为它将成为失败的一个重要原因。在体测定瓷嵌体边缘面积的定量变化。对12颗前磨牙进行全瓷嵌体修复，从嵌体植入时到修复后8年的全瓷嵌体复制体进行定量测量。采用高精度CCD激光扫描仪对正常牙合面进行形态学测量。用图像分析软件对横截面进行纵向叠加，计算边缘区的定量变化。在95%置信水平下，采用Mann-Whitney检验分析对定量变化有显著影响的因素。全瓷嵌体修复8年后，前磨牙功能区牙尖边缘的定量变化为465×10^2μm^2，非功能区牙尖边缘的定量变化为207×10^2μm^2。功能性和非功能性牙尖区的边缘崩解有显著差异。首次定量测量了陶瓷嵌体在体边缘的崩解。咬合力对瓷嵌体边缘崩解有重要影响。少

The quality of fired ceramic inlay restorations consisting of a feldspathic porcelain system (G-Cera Cosmotech II, GC Co., Tokyo, Japan) after 8 years was evaluated in vivo. A total of 45 fired ceramic inlays were placed in 25 patients, and all restorations were evaluated at the time of placement, and at 6 months and 1, 2, 4, 6 and 8 years after placement using modified U.S.P.H.S.criteria. Replicas made of the restorations were observed with a scanning electron microscope (SEM) to evaluate the degradation of the marginal area and wear loss of the restoration. Longevity was observed in 82% of the fired ceramic inlay restorations at 8 years (Kaplan-Meier method). Marginal fracture was detected in 11 restorations (22%) including bulk fracture in five (11%). Marginal discoloration and recurrent caries were observed in 14 (31%) and three (7%) restorations, respectively. The SEM evaluation disclosed marginal microfracture in 77% of the restorations, wear loss of the restoration in 36%, and w … More ear of resin cement along margin in 74% at 8 years. No significant difference was observed in the incidence of each of these three characteristics between molars and premolars ( Mann-Whitney test, p<0.05). This longitudinal 8-year clinical observation suggested that fired ceramic inlay restorations are clinically acceptable.Marginal disintegration of ceramic inlays is a problem which should be urgently addressed, because it will become a critical cause of failure as a bulk fracture. The quantitative change of the marginal area of ceramic inlays was determined in vivo. Replicas of 12 premolars restored with ceramic inlays were measured quantitatively from the time of placement to eight years after restoration. An accurate CCD optical laser scanner was employed for morphological measurement of occlusal surface of restorations. Quantitative changes at the marginal area were computed by longitudinal superimposition of the cross sections with a picture analyze software. Factors which had significant influence on the quantitative change were analyzed with the Mann-Whitney test at a 95% level of confidence. The quantitative marginal changes of premolars restored with ceramic inlays for eight years were 465×10^2μm^2 at functional cusp area and 207×10^2μm^2 at non-functional cusp area. There were significant differences in marginal disintegration between functional and non-functional cusp areas. In vivo marginal disintegration of ceramic inlays was first measured quantitatively. Occlusal force may have significant effect on the marginal disintegration of ceramic inlays. Less