Adelaide Dental School, The University of Adelaide, Adelaide, South Australia, Australia.
Aust Dent J. 2020 Jun;65(2):150-157. doi: 10.1111/adj.12748. Epub 2020 Mar 9.
The purpose of this study was to assess marginal gaps of CAD/CAM lithium disilicate crowns constructed using two different intraoral scanners of different generations.
Twenty four Columbia model lower left molars were prepared for lithium disilicate crowns in a simulated environment by undergraduate students. The crown preparations were scanned by E4D and Trios 3 intraoral scanners and CAD/CAM lithium disilicate crowns designed and manufactured. The crowns were seated onto the original crown preparations and three vertical marginal gap measurements taken at four locations (mid-buccal, mid-lingual, mid-mesial and mid-distal) using a stereomicroscope. The mean marginal gap (MMG) was calculated for each crown and each individual tooth surface.
The MMG was not statistically significantly different for the Trios 3 and E4D scanners (P = 0.111). There was no statistically significant effect of measurement location on the tooth on the marginal gap (P = 0.1134).
There was no difference in the MMGs of CAD/CAM lithium disilicate crowns constructed using two different intraoral scanners of different generations. Within the limitations of this study, the advances in scanning technology have produced small and insignificant improvements in the accuracy of crown margins.
本研究的目的是评估使用两代不同的口内扫描仪构建 CAD/CAM 锂硅酸盐冠的边缘间隙。
由本科生在模拟环境下对 24 个哥伦比亚模型左下磨牙进行锂硅酸盐冠预备。通过 E4D 和 Trio 3 口内扫描仪对牙冠预备体进行扫描，并设计和制作 CAD/CAM 锂硅酸盐冠。将牙冠试戴到原始牙冠预备体上，使用立体显微镜在四个位置（颊中、舌中、近中、远中）测量三个垂直边缘间隙。计算每个牙冠和每个牙面的平均边缘间隙（MMG）。
Trios 3 和 E4D 扫描仪的 MMG 无统计学差异（P=0.111）。测量位置对牙冠边缘间隙无统计学影响（P=0.1134）。
两代不同的口内扫描仪构建 CAD/CAM 锂硅酸盐冠的 MMG 无差异。在本研究的限制范围内，扫描技术的进步使牙冠边缘的准确性有了微小但无意义的提高。
