Al-Ali Amna Mohamed Ahmed Hassan, Khalifa Nadia, Hadj-Hamou Amir, Sheela Soumya, El-Damanhoury Hatem M
Department of Preventive and Restorative Dentistry, College of Dental Medicine, University of Sharjah, Sharjah, United Arab Emirates.
Dental Biomaterials Research Laboratory, Research Institute for Medical & Health Sciences, University of Sharjah, Sharjah, United Arab Emirates.
Eur J Dent. 2023 May;17(2):431-438. doi: 10.1055/s-0042-1745770. Epub 2022 Jun 21.
To evaluate the fatigue and fracture resistance of ultra-thin laminate veneers (UTLV) with two different thicknesses and two different bonding protocols.
A total of 64 flat enamel surfaces were assigned to either 0.2 or 0.4 mm UTLV. The UTLV were further subdivided and assigned to one of two bonding techniques: adhesive resin cement(RC( or preheated restorative resin composite (HC) ( = 16). Eight samples were fatigued with 750,000 mechanical cycles and 8,000 thermal cycles between 5 and 55°C in a chewing simulator, and the failure mode was evaluated using a stereomicroscope and SEM. The other eight samples from each group were loaded to failure in a universal testing machine to test the fracture resistance. Fisher's exact Probability test was used to analyze the fatigue test results, and two-way analysis of variance and Bonferroni's test were used to analyze the fracture resistance test results.
The difference in fatigue resistance between failure proportions in different groups was statistically different ( < 0.05). The 0.4-mm-thick UTLV had similar results regardless of the bonding technique, while 0.2-mm-thick UTLV only showed comparable results when cemented with preheated HC. No statistically significant difference was found in fracture resistance between the tested groups ( > 0.05).
The Bonding technique and the thickness of the UTLV had impacted fatigue resistance but had no significant effect on the fracture resistance. bonding of UTLV with preheated composite increases their fatigue resistance. Different testing approaches delivered different results.
评估两种不同厚度和两种不同粘结方案的超薄层压贴面（UTLV）的疲劳和抗折性能。
总共64个平坦的牙釉质表面被分配到0.2或0.4毫米的UTLV组。UTLV进一步细分并分配到两种粘结技术之一：粘结树脂水门汀（RC）或预热修复树脂复合材料（HC）（每组n = 16）。八个样本在咀嚼模拟器中进行750,000次机械循环和5至55°C之间8,000次热循环的疲劳测试，并使用立体显微镜和扫描电子显微镜评估失效模式。每组的另外八个样本在万能试验机上加载直至破坏，以测试抗折性能。采用Fisher精确概率检验分析疲劳测试结果，采用双向方差分析和Bonferroni检验分析抗折性能测试结果。
不同组失效比例之间的疲劳抗力差异具有统计学意义（P < 0.05）。无论粘结技术如何，0.4毫米厚的UTLV结果相似，而0.2毫米厚的UTLV仅在用预热的HC粘结时显示出可比的结果。测试组之间的抗折性能没有统计学显著差异（P > 0.05）。
粘结技术和UTLV的厚度影响疲劳抗力，但对抗折性能没有显著影响。用预热复合材料粘结UTLV可提高其疲劳抗力。不同的测试方法得出不同的结果。
