氧化锆和纯钛基底冠材料及饰瓷烧结对种植全冠适合性的影响

目的 研究氧化锆和纯钛基底冠材料及饰瓷烧结对种植全冠内部和边缘适合性的影响。方法 制作计算机辅助设计/计算机辅助制作（CAD/CAM）氧化锆烤瓷种植全冠（A组）和纯钛烤瓷种植全冠（B组）各8个（n=8）。分别用硅橡胶轻体复制饰瓷烧结前基底冠和饰瓷烧结后全冠的内部和边缘间隙，采用Micro-CT扫描硅橡胶，建立三维图像，测量冠边缘垂直间隙（MG）、冠边缘水平间隙（HMD）和冠内部轴面中点间隙（AW）。采用SPSS 17.0软件对测量结果进行统计学分析。结果 饰瓷烧结前，A组基底冠MG、HMD和AW均大于B组（P<0.05）。饰瓷烧结后，A组全冠MG小于B组（P<0.05），两组的HMD和AW均无统计学差异（P>0.05）。饰瓷烧结使A组MG减小（P<0.05），使B组MG、HMD和AW均增大（P<0.05），而A组HMD和AW烧结前和烧结后的差异无统计学意义（P>0.05）。结论 氧化锆烤瓷种植全冠边缘适合性优于纯钛烤瓷种植全冠；饰瓷烧结对氧化锆和纯钛烤瓷种植全冠适合性均会产生影响。

Influence of coping material selection and porcelain firing on marginal and internal fit of computer-aided design/computer-aided manufacturing of zirconia and titanium ceramic implant-supported crowns

Objective This study aimed to investigate the influence of coping material and porcelain firing on the marginal and internal fit of computer-aided design/computer-aided manufacturing (CAD/CAM) of zirconia ceramic implant- and titanium ceramic implant-supported crowns. Methods Zirconia ceramic implant (group A, n=8) and titanium metal ceramic implantsupported crowns (group B, n=8) were produced from copings using the CAD/CAM system. The marginal and internal gaps of the copings and crowns were measured by using a light-body silicone replica technique combined with micro-computed tomog-raphy scanning to obtain a three-dimensional image. Marginal gap (MG), horizontal marginal discrepancy (HMD), and axial wall (AW) were measured. Statistical analyses were performed using SPSS 17.0. Results Prior to porcelain firing, the measurements for MG, HMD, and AW of copings in group A were significantly larger than those in group B (P<0.05). After porcelain firing, the measurements for MG of crowns in group A were smaller than those in group B (P<0.05), whereas HMD and AW showed no significant difference between the two groups (P>0.05). Porcelain firing significantly reduced MG (P<0.05) in group A but significantly increased MG, HMD, and AW in group B (P<0.05). HMD and AW were not influenced by porcelain firing in group A (P>0.05). Conclusion The marginal fits of CAD/CAM zirconia ceramic implant-supported crowns were superior to those of CAD/CAM titanium ceramic-supported crowns. The fits of both the CAD/CAM zirconia ceramic implant- and titanium ceramic implant-supported crowns were obviously influenced by porcelain firing.