Effect of cement gap and drill offset on the marginal and internal fit discrepancies of crowns designed with different tooth preparations

作者全名："Xu, Shu-Xi; Tong, Xue-Lu; Tan, Fa-Bing; Yu, Na; Ma, Chao-Yi"

作者地址："[Xu, Shu-Xi; Tong, Xue-Lu; Tan, Fa-Bing; Yu, Na; Ma, Chao-Yi] Chongqing Med Univ, Coll Stomatol, Chongqing, Peoples R China; [Tan, Fa-Bing] Chongqing Key Lab Oral Dis & Biomed Sci, Chongqing, Peoples R China; [Tan, Fa-Bing; Yu, Na; Ma, Chao-Yi] Chongqing Municipal Key Lab Oral Biomed Engn High, Chongqing, Peoples R China"

通信作者："Tan, FB (通讯作者)，Chongqing Med Univ, Coll Stomatol, Chongqing, Peoples R China.; Tan, FB (通讯作者)，Chongqing Key Lab Oral Dis & Biomed Sci, Chongqing, Peoples R China.; Tan, FB (通讯作者)，Chongqing Municipal Key Lab Oral Biomed Engn High, Chongqing, Peoples R China."

来源：INTERNATIONAL JOURNAL OF COMPUTERIZED DENTISTRY

ESI学科分类：CLINICAL MEDICINE

WOS号：WOS:001144011300002

JCR分区：Q2

影响因子：1.7

年份：2023

卷号：26

期号：4

开始页：319

结束页：330

文献类型：Article

关键词：computer-aided design; drill offset; cement gap; tooth preparation design; fixed crown; fit discrepancies

摘要："Aim: The aim of the present study was to evaluate the effect of cement gap and drill offset on the marginal and internal fit discrepancies of crowns designed with different tooth preparations. Materials and methods: Five tooth preparations were constructed, and crowns with different cement gaps and drill offsets were obtained. Then, best-fit alignment was performed on the crowns with the corresponding tooth preparations, and the fit discrepancies were expressed by color-coded difference images and root mean square (RMS) values. The RMS values of each group were analyzed by the rank-based Scheirer-Ray-Hare test (alpha = 0.05). Results: The color segments in the sharp line angles area of the Sharp line angles group changed significantly before and after the drill offset. The cement gap had a significant effect on the marginal, internal, or overall fit discrepancies of the five design groups (P < 0.001), while the drill offset had a significant effect on the marginal fit discrepancies of the Shoulder-lip group and the internal or overall fit discrepancies of the Sharp line angles group (P < 0.001). Additionally, the interaction effect between cement gap and drill offset was significant for the marginal fit discrepancies of the Shoulder-lip group and the internal or overall fit discrepancies of the Sharp line angles group (P < 0.01). Conclusions: The cement gap and drill offset had a significant adverse effect on the marginal or internal fit discrepancies of the crowns designed with the shoulder-lip and sharp line angles designs. Tooth preparation designs with intense curvature changes such as shoulder-lip and sharp line angles should be avoided clinically."

基金机构：Natural Science Foundation of Chongqing [cstc2020jscx-sbqwX0006]; Scientific and Technological Research Program of Chongqing Municipal Education [KJQN 202100439]

基金资助正文：The present work was supported by the Natural Science Foundation of Chongqing (No. cstc2020jscx-sbqwX0006); Scientific and Technological Research Program of Chongqing Municipal Education (No. KJQN 202100439).