Kuijs R H, Fennis W M M, Kreulen C M, Roeters F J M, Verdonschot N, Creugers N H J
Department of Preventive and Curative Dentistry, Radboud University Medical Centre Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
J Dent. 2006 Jan;34(1):19-25. doi: 10.1016/j.jdent.2005.02.010. Epub 2005 Jun 2.
To investigate the fatigue resistance and failure behaviour of cusp-replacing restorations in premolars using different types of adhesive restorative materials.
A class 2 cavity was prepared and the buccal cusp was removed in an extracted sound human upper premolar. By using a copy-milling machine this preparation was copied to 60 human upper premolars. In groups of 20 premolars each, direct resin composite restorations, indirect resin composite restorations and ceramic restorations were made. All restorations were cusp replacements made in standardized shape and with adhesive techniques. Cyclic load (5 Hz) was applied starting with a load of 200 N (10,000 cycles) followed by stages of 400, 600, 800 and 1000 N at a maximum of 50,000 cycles each. Samples were loaded until fracture or to 2,10,000 cycles maximum. In case of fracture, the failure mode was recorded.
No differences were seen in fracture strength between the three groups (Wilcoxon P = 0.16). No differences were observed with regard to failure mode above or below the cemento enamel junctions (chi2 P = 0.63). The indirect resin composite and ceramic restorations showed significantly more combined cohesive and adhesive fractures than the direct resin composite restorations, which showed more adhesive fractures (chi2 P = 0.03 and 0.002).
The results of this study suggest that ceramic, indirect resin composite and direct resin composite restorations provide comparable fatigue resistance and exhibit comparable failure modes in case of fracture, although the indirect restorations tend to fracture more cohesively than the direct restorations.
使用不同类型的粘结性修复材料，研究前磨牙尖替代修复体的抗疲劳性和失效行为。
在一颗拔除的完好人类上颌前磨牙上制备Ⅱ类洞型并去除颊尖。使用复制铣床将该制备模型复制到60颗人类上颌前磨牙上。将前磨牙分成每组20颗，分别制作直接树脂复合材料修复体、间接树脂复合材料修复体和陶瓷修复体。所有修复体均采用标准化形状并使用粘结技术进行尖替代修复。以200N的载荷开始施加循环载荷（5Hz）（10000次循环），随后依次施加400、600、800和1000N的载荷，每组最多50000次循环。对样本加载直至断裂或最多加载210000次循环。若发生断裂，则记录失效模式。
三组之间的断裂强度无差异（Wilcoxon检验P = 0.16）。在牙骨质釉质界上方或下方的失效模式方面未观察到差异（卡方检验P = 0.63）。间接树脂复合材料和陶瓷修复体显示出比直接树脂复合材料修复体显著更多的粘结和粘结性混合断裂，而直接树脂复合材料修复体显示出更多的粘结性断裂（卡方检验P = 0.03和0.002）。
本研究结果表明，陶瓷、间接树脂复合材料和直接树脂复合材料修复体具有相当的抗疲劳性，并且在断裂时表现出相当的失效模式，尽管间接修复体比直接修复体更倾向于发生粘结性断裂。
