不同椅旁可切削修复材料序列抛光时间及表面粗糙度与光泽度的比较

目的: 比较不同种类计算机辅助设计/辅助制作(computer aided design/manufacturing, CAD/CAM)修复材料抛光后表面粗糙度值(Ra值)与光泽度值的差异, 测定适宜的抛光时间, 为操作者抛光椅旁可切削修复体提供参考。方法: 选择5种不同种类CAD/CAM修复材料长石瓷(vita mark Ⅱ, VM)、弹性瓷(vita enamic, VE)、优韧瓷(lava ulimate, LU)、复合树脂A(shofu block HC, SB)和复合树脂B(brilliant crios, BC), 每种材料制备6个试样, 共30个试样。将试样固定于自制抛光装置, 使用Sof-Lex抛光碟系统中的中碟(medium disk, M碟, 磨粒粒径10~40 μm)、细碟(fine disk, F碟, 磨粒粒径3~9 μm)和超细碟(superfine disk, SF碟, 磨粒粒径1~7 μm)依次对试样进行序列抛光。试样每抛光10 s测量一次Ra值及光泽度值, 数值不再变化时更换下一级抛光碟, 每个抛光碟仅使用一次。更换下一级抛光碟的同时记录试样的Ra值、光泽度值以及抛光时间, 实验完成后用SPSS 24.0软件进行统计学分析。结果: 序列抛光后所有材料Ra值较抛光前显著降低(P < 0.05), 光泽度值显著升高(P < 0.05)。不同材料间的Ra值差异无统计学意义(P＞0.05), 而LU的光泽度值[(68.1±4.5) GU]与SB的光泽度值[(68.2±5.8) GU]显著高于VE[(48.1±8.1) GU]与BC[(53.2±5.8) GU], P < 0.05。达到最佳Ra值和光泽度值, VM [40(30, 55) s]所需总抛光时间最短, VE [140(135, 145) s]、LU [130(120, 140) s]、SB [140(130, 150) s]与BC [130(120, 140) s]的抛光时间差异无统计学意义。结论: 所有CAD/CAM修复材料经Sof-Lex抛光碟系统序列抛光后均能显著降低表面粗糙度值和提高光泽度值; 不同材料达到最佳表面粗糙度和光泽度所需的抛光时间不同; 推荐使用Sof-Lex系统抛光时, 对于长石瓷, 仅用M碟抛光40 s即可。对于弹性瓷、优韧瓷、复合树脂A与复合树脂B, 要序列使用M碟、F碟和SF碟抛光, 总体抛光时间约130~140 s。

Surface roughness,gloss and sequential polishing times of various chairside computer aided design/manufacturing restorative materials

Objective: To investigate the effect of polishing on surface roughness, gloss and optimum polishing time of various computer aided design/computer aided manufacturing (CAD/CAM) restorative materials and to provide a proper polishing procedure for dental clinicians. Methods: Five CAD/CAM restorative materials including vita mark Ⅱ (VM), vita enamic (VE), lava ultimate (LU), shofu block HC (SB) and brilliant crios (BC) were selected. Six specimens were prepared for each material. The specimen was fixed on a custom-made polishing apparatus and sequentially polished with Sof-Lex poli-shing disk system including medium disk (with abrasive particle sizes of 10-40 μm), fine disk (with abrasive particle sizes of 3-9 μm) and superfine disk (with abrasive particle sizes of 1-7 μm). Surface roughness (Ra value) and gloss value were measured every 10 seconds until the numerical values were no longer changed. Then the surface roughness, gloss value and polishing time were recorded and the specimen was moved to the next sequence of polishing. Finally, statistical analysis was performed using SPSS 24.0. Results: For all the restorative materials, the Ra values were significantly reduced (P < 0.05) and the gloss values were significantly increased (P < 0.05) after sequentially polishing with Sof-Lex disks. No significant difference was detected among Ra values of all the tested materials (P>0.05) after sequential polishing. The gloss values of LU [(68.1±4.5) GU] and BC [(68.2±5.8) GU] were significantly higher than those of VE [(48.1±8.1) GU] and BC [(53.2±5.8) GU], P < 0.05. To obtain optimal surface smoothness, VM cost the shortest polishing time [40 (30, 55) s] among all the restorative materials (P < 0.05). No significant differences in the total polishing time were observed among VE [140 (135, 145) s], LU [130 (120, 140) s], SB [140 (130, 150) s] and BC [130 (120, 140) s], P>0.05. Conclusion: The surface roughness of all CAD/CAM restorative materials were decreased after sequentially polishing with Sof-Lex disk system. To obtain the smoothest surface, different types of restorative materials might need different polishing times using Sof-Lex polishing disk system. For ceramic restorative material VM, we recommend polishing only with medium disk for 40 s. For hybrid restorative material VE and composite restorative material LU, SB and BC, we recommend polishing with medium disk, fine disk and superfine disk in sequence for 130-140 s in total.