Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia.
Aust Dent J. 2024 Sep;69(3):189-196. doi: 10.1111/adj.13014. Epub 2024 Mar 12.
This study compared the marginal gaps of CAD/CAM lithium disilicate (LDS) crowns constructed using a contemporary and older scanner/milling unit combination at three different cement spaces.
Twenty-four undergraduate students prepared a Columbia model lower left first molar for an LDS crown in a simulated environment. From each crown preparation, one LDS crown was constructed using an E4D scanner/E4D milling unit (E4DS/E4DM) and TRIOS 3 scanner/Sirona inLab MC X5 milling unit (TRIO/MCX5) at cement space settings of 50, 100 and 200 μm. Each LDS crown was positioned onto the original crown preparation, and then a stereomicroscope was used to make three vertical marginal gap measurements at four locations (mid-buccal, mid-lingual, mid-mesial and mid-distal). The mean marginal gap (MMG) was calculated for each crown and each individual tooth surface.
The MMGs of CAD/CAM LDS crowns constructed by TRIO/MCX5 were 72.31 at 50, 63.73 at 100 μm and 46.23 μm at 200 μm, which were smaller than E4DS/E4DM at each cement space.
Increasing the cement space decreased the MMG in both scanner/milling unit combinations. The smallest MMG was found using the newer scanner/milling unit at the 200 μm cement space. © 2024 Australian Dental Association.
本研究比较了在三种不同的粘结间隙下，使用现代和较老的扫描/铣削设备组合制作 CAD/CAM 锂硅玻璃陶瓷（LDS）冠的边缘间隙。
24 名本科生在模拟环境中为哥伦比亚模型左下第一磨牙制备 LDS 冠。从每个冠预备体中，使用 E4D 扫描仪/E4D 铣削单元（E4DS/E4DM）和 TRIOS 3 扫描仪/Sirona inLab MC X5 铣削单元（TRIO/MCX5），在粘结间隙设置为 50、100 和 200 μm 的情况下分别制作一个 LDS 冠。将每个 LDS 冠放置在原始冠预备体上，然后使用立体显微镜在四个位置（颊中、舌中、近中、远中）进行三个垂直边缘间隙测量。为每个冠和每个个体牙面计算平均边缘间隙（MMG）。
TRIO/MCX5 制作的 CAD/CAM LDS 冠的 MMG 在 50 μm 时为 72.31 μm，在 100 μm 时为 63.73 μm，在 200 μm 时为 46.23 μm，在每个粘结间隙处均小于 E4DS/E4DM。
增加粘结间隙会减小两种扫描/铣削设备组合的 MMG。在 200 μm 的粘结间隙下，使用较新的扫描/铣削单元可获得最小的 MMG。 © 2024 澳大利亚牙科协会。
