UCL Eastman Dental Institute.
Eur J Prosthodont Restor Dent. 2021 Aug 31;29(3). doi: 10.1922/EJPRD_2108Sambrook07.
This study was designed to assess the fit of cobalt chromium copings fabricated using direct metal laser sintering and to compare with copings fabricated from nickel chromium (traditional casting) and zirconia (milled from partially sintered blanks). For both cobalt chromium and zirconia groups, impressions were generated using direct or indirect digitization. There were 5 experimental groups of 12 copings fabricated for a prepared maxillary right molar. The intimacy of fit (measured at the margin, axial wall and occlusal) was assessed using a replica method technique. The results showed that zirconia copings produced using direct digitization had significantly smaller marginal, axial and occlusal measurements compared to other groups (p⟨0.05). Nevertheless, all groups had a mean marginal gap within accepted clinical values. Though there was a decrease in the intimacy of fit from the margin to axial wall to the occlusal surface. It can be concluded that the fit of zirconia copings fabricated using direct digitization was significantly better than the other groups. However, it can be expected that further enhancement and refinement of additive technology such as direct metal laser sintering will offer clinicians a viable alternative to nickel chromium analogue production methods in the future.
本研究旨在评估使用直接金属激光烧结制作的钴铬金属冠的适合性，并与镍铬（传统铸造）和氧化锆（从部分烧结坯料铣削而成）制作的冠进行比较。对于钴铬和氧化锆两组，使用直接或间接数字化技术生成印模。为制备的右上颌磨牙制作了 5 个实验组，每组 12 个冠。使用复制技术评估适合性（在边缘、轴向壁和咬合面测量）。结果表明，与其他组相比，使用直接数字化制作的氧化锆冠在边缘、轴向和咬合面的测量值明显更小（p ⟨ 0.05）。然而，所有组的边缘间隙平均值都在可接受的临床范围内。尽管从边缘到轴向壁到咬合面的适合性都有所下降。可以得出结论，使用直接数字化制作的氧化锆冠的适合性明显优于其他组。然而，可以预期，直接金属激光烧结等添加剂技术的进一步增强和改进将为临床医生提供一种可行的替代镍铬类似物生产方法的选择。
