不同大块充填树脂对Ⅱ类洞龈壁密合性的影响

Influence of Types of Bulk-fill Resin-based Composite on Gingival Adaption in Class Ⅱ Restorations

目的:研究不同的大块充填树脂对Ⅱ类洞修复体龈壁密合性的影响。方法:体外收集28颗被拔出的人类第三磨牙。每颗离体牙分别制备出近中邻颌面洞和远中邻颌面洞2个标准的Ⅱ类洞(2 mm×3 mm×4 mm)。总共56个Ⅱ类洞随机分为7组(n=8),分别使用2种低黏型和3种高黏型大块充填树脂充填作为实验组,两种传统树脂充填作为对照组。固化的同时对修复体进行声发射(Acoustic emission,AE)的检测,记录从固化开始到1000s内间隙产生时的声学信号。采用光学相干断层扫描(Optical coherence tomography,OCT)对每个Ⅱ类洞修复体龈壁进行密合性的检测。将实验数据进行单因素方差分析。结果:低黏型大块充填树脂(B组;C组)的声发射事件数(15.7;17.6)和裂隙比(16.1;14.1)显著低于其他种类树脂(P<0.05),在Ⅱ类洞充填时,低黏型大块充填树脂拥有更好的龈壁边缘密合性。声发射和光学相干断层扫描之间的皮尔逊相关系数(Pearson correlation coefficient)为0.941。结论:使用低黏型大块充填树脂充填Ⅱ类洞时,龈壁会获得更好的密合性。声发射和光学相干断层扫描可以被协同用于对树脂修复体密合性的检测。

Objective：To investigate the effects of bulk-fill resin-based composite type on gingival adaption of classⅡcavities.Methods：Twenty-eight extracted human third molars were collected.Two classⅡcavites（2 x3 x4 mm）were prepared on mesial and distal surfaces of each tooth.Class Ⅱ cavities were randomly divided into 7 groups（n=8）,and the cavities were restored by 2 low viscosity,3 high viscosity bulk-fill resin-based composites or 2 conventional resin-based composites,respectively.Acoustic emission（AE）signals were recorded from the beginning of light-curing of resin composite and lasted for 1000 s.The percentage of microleakage formation（M%）were calculated using optical coherence tomography（OCT）.Data obtained from AE and OCT were statistically analyzed using one-way ANOVA.Results：Two low viscosity bulk-fill resin-based composites generated significantly less AE events（15.7;17.6）and lower M%（16.1;14.1）（P〈0.05）.Pearson correlation coefficient was 0.941 between AE test and OCT（P〈0.05）.Conclusion：The low-viscosity bulk-fill resin composites demonstrate better internal adaption in classⅡ resotorations.AE and OCT can be used to assess the marginal integrity of resin composites.