Bonilla E D, Hayashi M, Pameijer C H, Le N V, Morrow B R, Garcia-Godoy F
University of California, Los Angeles, School of Dentistry, Los Angeles, CA, USA.
Researcher and Vice Chair of the Section of Restorative, Dentistry, University of California, Los Angeles, CA, USA.
J Dent. 2020 Oct;101:103348. doi: 10.1016/j.jdent.2020.103348. Epub 2020 May 15.
The aim of this in vitro study was to compare the effect of two restorative placement techniques, centripetal incremental technique (CIT) and bulk-fill technique (BT) on the fracture resistance of Class II MOD restorations with various resin composites in molar teeth.
Fifty-six extracted, caries free third molars were prepared with MOD preparations and restored with resin composites. The specimens were divided into two groups by placement technique, centripetal incremental technique (CIT) and bulk-fill technique (BT). Each group was subdivided into four groups according to resin composite: hybrid (Aelite LS), nano-hybrid (Virtuoso Universal), bulk fill (Filtek One Bulk Fill) and the micro-hybrid (Herculite XRV) as the control.
Two-way analysis of variance test (ANOVA) followed by the multiple comparison procedure, Student-Newman-Keuls Method showed no a statistically significant difference between placement techniques and fracture resistance of Class II resin composite restorations (P > 0.05). Herculite XRV resisted a significantly higher load before fracture than the other three materials at a 0.05 level of significance, while Virtuoso Universal scored the lowest load.
There was no significant effect of the two placement techniques on the fracture resistance of Class II resin composite restorations CLINICAL SIGNIFICANCE: Resin composite restorations in Class II MODs using a simplified bulk fill placement technique showed no significant difference in fracture resistance with the centripetal technique in molar teeth.
本体外研究的目的是比较两种修复体放置技术，即向心递增技术（CIT）和一次性充填技术（BT）对磨牙中不同树脂复合材料的Ⅱ类MOD修复体抗折性的影响。
选取56颗拔除的、无龋的第三磨牙，制备MOD洞型，并用树脂复合材料进行修复。根据放置技术将标本分为两组，即向心递增技术（CIT）组和一次性充填技术（BT）组。每组根据树脂复合材料再细分为四组：混合型（Aelite LS）、纳米混合型（Virtuoso Universal）、一次性充填型（Filtek One Bulk Fill）和微混合型（Herculite XRV，作为对照）。
采用双因素方差分析（ANOVA），随后进行多重比较程序，即Student-Newman-Keuls法，结果显示Ⅱ类树脂复合材料修复体的放置技术与抗折性之间无统计学显著差异（P＞0.05）。在0.05的显著性水平下，Herculite XRV在断裂前抵抗的载荷明显高于其他三种材料，而Virtuoso Universal的载荷得分最低。
两种放置技术对Ⅱ类树脂复合材料修复体的抗折性无显著影响。临床意义：在Ⅱ类MOD中使用简化的一次性充填放置技术的树脂复合材料修复体，在磨牙中与向心技术相比，抗折性无显著差异。
