曹程，李平，屈直

（锦州医科大学1. 研究生院； 2. 附属第二医院修复科，辽宁 锦州 121000）

粘接剂排溢沟对后牙氧化锆全冠适合性的影响

曹程1，李平1，屈直2

（锦州医科大学1. 研究生院； 2. 附属第二医院修复科，辽宁 锦州 121000）

目的研究粘接剂排溢沟对后牙全冠适合性的影响。方法三维建模一颗下颌第一磨牙，在Rhinoceros 5.0软件中设计4种预备体模型：A为常规全冠预备设计，B、C、D分别在A组的基础上设计1、2、4个粘接剂排溢沟，3D打印树脂预备体各5个。根据A预备体设计全冠，CAD/CAM制作氧化锆全冠20个，完全随机分为4组。三维扫描仪扫描试件，进行偏差分析及壁厚分析。硅橡胶法复制冠与预备体之间的间隙，金相显微镜下观察，并测量间隙大小。SPSS 17.0软件进行统计分析。结果全冠边缘和内部间隙从大到小依次为A组、B组、C组、D组，两两比较差异有统计学意义（P ＜ 0.05）。结论粘接剂排溢沟能显著提高全冠的适合性，且排溢沟数量越多，全冠适合性越好。

粘接剂排溢沟； 边缘适合性； 内部适合性

Abstract ObjectiveTo study the effect of adhesive overflow grooves on the marginal and internal adaptation of a molar zirconia full crown.MethodsA three-dimensional model of a mandibular first molar was established. Four crown preparations （A-D） were designed：a was a conventional full crown design，and B，C，and D included 1，2，and 4 adhesive overflow grooves，respectively，designed on the basis of A. Five resin preparations were created for each group using three-dimensional （3D） printing. According to the a design data，20 CAD/CAM zirconia crowns were prepared and randomly divided into four groups. The tooth，preparations，and crowns underwent 3D scanning for 3D deviation analysis and 3D wall thickness analysis. The gap between the crown and the preparation was replicated with silicone rubber，and then observed with a metallographic microscope and measured. Data were statistically analyzed with SPSS 17.0.ResultsAmong the groups，marginal and internal clearance was A＞B＞C＞D. The comparison between every two groups was statistically different （P ＜ 0.05）.ConclusionIncreases in the number of overflow grooves result in significant increases in the marginal adaptation and internal adaptation of a full crown.

Keywordsadhesive overflow groove； marginal adaptation； internal adaptation

全冠适合性是修复体与预备牙之间的间隙，包括边缘适合性和内部适合性［1］，其体现牙冠与牙体接触的密合程度，临床上用粘接剂厚度来表示［2］。提高全冠的适合性，不仅能提升美学效果、增加冠的固位、延长牙冠的使用寿命，还能在长期使用中减少粘接剂溶解和微渗漏［3-4］。因此提高全冠适合性具有重要的临床意义。

影响全冠适合性的因素很多，其中冠的粘接是造成冠适合性下降的重要因素之一。冠在粘接就位过程中，内压会不断升高，过高的内压会阻碍粘接剂的排溢，多余的粘接剂滞留在修复体和预备牙之间，增加了冠的浮出量，降低了冠的适合性［5-7］。……