Sagsoz N Polat, Yanıkoglu N
Department of Dental Prosthesis Technology, Health Services Vocational School, Ataturk University, Erzurum, Turkey.
Department of Prosthodontics, Faculty of Dentistry, University of Atatürk, Erzurum, Turkey.
Niger J Clin Pract. 2018 Apr;21(4):417-422. doi: 10.4103/njcp.njcp_137_17.
The purpose of this study was to evaluate the fracture resistance of monolithic computer-aided design/computer-aided manufacturing (CAD/CAM) crowns that are prepared with different cement thickness.
For this investigation, a human maxillary premolar tooth was selected. Master model preparation was performed with a demand bur under water spray. Master die was taken to fabricate 105 epoxy resin replicas. The crowns were milled using a CEREC 4 CAD/CAM system (Software Version, 4.2.0.57192). CAD/CAM crowns were made using resin nanoceramic, feldspathic glass ceramic, lithium disilicate, and leucite-reinforced ceramics. Each group was subdivided into three groups in accordance with three different cement thicknesses (30, 90, and 150 μm). Crowns milled out. Then RelyX U200 was used as a luting agent to bond the crowns to the prepared samples. After one hour cementations, the specimens were stored in water bath at 37°C for 1 week before testing. Seven unprepared and unrestored teeth were kept and tested as a control group. A universal test machine was used to assume the fracture resistance of all specimens. The compressive load (N) that caused fracture was recorded for each specimen. Fracture resistance data were statistically analyzed by one-way ANOVA and two-factor interaction modeling test (α = 0.001).
There are statistically significant differences between fracture resistances of CAD/CAM monolithic crown materials (P < 0.001). It is seen that cement thickness is not statistically significant for fracture resistance of CAD/CAM monolithic crowns (P > 0.001).
CAD/CAM monolithic crown materials affected fracture resistance. Cement thickness (30, 90, and 150 μm) was not effective on fracture resistance of CAD/CAM monolithic crowns.
本研究的目的是评估采用不同粘结剂厚度制备的整体式计算机辅助设计/计算机辅助制造(CAD/CAM)全冠的抗折强度。
本研究选取一颗人类上颌前磨牙。在喷水条件下使用按需车针进行主模型制备。制作主代型以制备105个环氧树脂复制品。使用CEREC 4 CAD/CAM系统(软件版本4.2.0.57192)研磨全冠。CAD/CAM全冠采用树脂纳米陶瓷、长石质玻璃陶瓷、二硅酸锂和白榴石增强陶瓷制作。根据三种不同的粘结剂厚度(30、90和150μm)将每组再细分为三组。全冠研磨完成后。然后使用RelyX U200作为粘结剂将全冠粘结至制备好的样本上。粘结一小时后,在测试前将标本在37℃水浴中保存1周。保留7颗未制备和未修复的牙齿作为对照组进行测试。使用万能试验机测定所有标本的抗折强度。记录每个标本导致断裂的压缩载荷(N)。抗折强度数据通过单因素方差分析和双因素交互建模测试进行统计学分析(α = 0.001)。
CAD/CAM整体式全冠材料的抗折强度之间存在统计学显著差异(P < 0.001)。可以看出,粘结剂厚度对CAD/CAM整体式全冠的抗折强度无统计学显著影响(P > 0.001)。
CAD/CAM整体式全冠材料影响抗折强度。粘结剂厚度(30、90和150μm)对CAD/CAM整体式全冠的抗折强度无影响。