不同材料全冠修复体边缘适合性的比较研究

Comparative study on marginal adaptation of full crowns made of different materials

目的研究4种材料全冠修复体的边缘适合性,为临床修复体材料的选择提供参考依据。方法本研究于2022年1—4月在内蒙古口腔颅颌面疾病研究重点实验室进行。将种植基台作为预备体,直接在基台表面采用失蜡铸造工艺制作钴铬合金和金合金全冠修复体各20个,分别记为铸造钴铬合金组和铸造金合金组;采用计算机辅助设计与制造(CAD/CAM)切削工艺制作二氧化锆和纯钛全冠修复体各20个,分别记为CAD/CAM二氧化锆组和CAD/CAM纯钛组。各组初步试戴并记录调磨全冠组织面达到完全就位的时间。使用体视显微镜和M2-cam软件观测各组全冠修复体的绝对边缘间隙。结果各组调磨就位时间总的比较,差异有统计学意义(F=91.519,P<0.001)。其中,铸造钴铬合金组调磨就位时间[(14.1±2.6)min]最长,CAD/CAM二氧化锆组用时[(5.0±1.6)min]最短,差异均有统计学意义(均P<0.05)。各组绝对边缘间隙由小至大依次为CAD/CAM二氧化锆组[(12.19±4.11)μm]、CAD/CAM纯钛组[(18.46±4.65)μm]、铸造金合金组[(28.93±4.24)μm]和铸造钴铬合金组[(42.71±6.94)μm],其差异均有统计学意义(均P<0.05)。结论4种全冠修复材料中二氧化锆通过CAD/CAM制作的全冠修复体精度更高,更易调磨达到完全就位,且边缘适合性更好。

Objective To study the marginal adaptation of full crowns made of four different materials and provide references for the selection of clinical prosthetic materials.Methods The study was finished in the Inner Mongolia Key Laboratory of Oral Craniofacial Diseases from January 2022 to April 2022.Using the implant abutment as the preparation,40cast full crowns made of cobalt chromium and gold alloy were fabricated directly on the abutment by lost-wax casting technique,which were divided into cast cobalt chromium alloy group and cast gold alloy group.Similarly,another 40 full crowns made of zirconia and pure titanium were fabricated by CAD/CAM technique,which were recorded as CAD/CAM zirconia group and CAD/CAM pure titanium group.All crowns were initially tried on the abutment,and the time of grinding the tissue surface of crown to achieve the complete seating was recorded.The absolute marginal discrepancy(AMD)values were measured using the stereomicroscope and macro-measurement software M2-cam.Results There was a significant difference(F=91.519,P<0.001)in the grinding time to achieve the complete seating among groups.Among them,the time of grinding was the longest in the cast cobalt chromium alloy group[(14.1±2.6)min]and the shortest in the CAD/CAM zirconia group[(5.0±1.6)min],with statistically significant differences(P<0.05);the AMD values of each group from small to large were CAD/CAM zirconia group[(12.19±4.11)μm],CAD/CAM pure titanium group[(18.46±4.65)μm],cast gold alloy group[(28.93±4.24)μm]and cast cobalt chromium alloy group[(42.71±6.94)μm].The differences were statistically significant(all P<0.05).Conclusion The zirconia crown fabricated by CAD/CAM among the four materials has higher manufacturing accuracy,is easier to grind to achieve complete seating,and has better marginal adaptation.