Kwansirikul Anawat, Sae-Lee Daraporn, Angwaravong Onauma, Angwarawong Thidarat
Faculty of Dentistry, Department of Prosthodontics, Khon Kaen University, Khon Kaen, Thailand.
Faculty of Dentistry, Division of Pediatric Dentistry, Department of Preventive Dentistry, Khon Kaen University, Khon Kaen, Thailand.
Eur J Oral Sci. 2020 Jun;128(3):263-273. doi: 10.1111/eos.12699. Epub 2020 May 12.
The objectives of this study were to evaluate the micro-tensile bond strength (μTBS) of composite bonded to human occlusal sclerotic dentin following different surface treatments to determine the sclerotic dentin morphology. Human molars without (normal dentin; group 1) or with occlusal wear (sclerotic dentin; groups 2-5) were divided and subjected to different surface treatments, including the normal protocol for the Contax self-etch bonding system (group 1 and 2); doubled etch-prime time (group 3); pre-conditioning with 37% phosphoric acid before normal protocol (group 4); or pre-conditioning with 37% phosphoric acid before doubling the self-etching time (group 5). All teeth were restored with composite (Luxacore Z dual), sectioned into stick specimens and stored for 24 h in water before specimens were subjected to the μTBS test (n = 50 per group). The μTBS of normal dentin was not statistically significantly different from that of the sclerotic dentin groups, except for the doubled etch-prime time group which showed lower μTBS. Sclerotic dentin pre-treated with phosphoric acid resulted in less sclerotic casts and wider dentinal tubules, while doubled etch-prime time did not alter the morphology, as shown by scanning electron microscopy. In conclusion, the use of 37% phosphoric acid before applying self-etch bonding resulted in more tubule openings and a significantly higher μTBS when compared with the doubled etch-prime time group.
本研究的目的是评估在不同表面处理后，复合树脂与人类咬合面硬化牙本质的微拉伸粘结强度（μTBS），以确定硬化牙本质的形态。将未发生咬合磨损的人类磨牙（正常牙本质；第1组）和发生咬合磨损的磨牙（硬化牙本质；第2 - 5组）进行分组，并进行不同的表面处理，包括Contax自酸蚀粘结系统的常规处理（第1组和第2组）；酸蚀 - 预处理时间加倍（第3组）；在常规处理前用37%磷酸预处理（第4组）；或在自酸蚀时间加倍前用37%磷酸预处理（第5组）。所有牙齿均用复合树脂（Luxacore Z dual）修复，切成棒状标本，在进行μTBS测试前在水中储存24小时（每组n = 50）。除酸蚀 - 预处理时间加倍组的μTBS较低外，正常牙本质的μTBS与硬化牙本质组相比无统计学显著差异。扫描电子显微镜显示，用磷酸预处理的硬化牙本质产生的硬化铸型较少，牙本质小管较宽，而酸蚀 - 预处理时间加倍并未改变形态。总之，与酸蚀 - 预处理时间加倍组相比，在应用自酸蚀粘结前使用37%磷酸可使更多小管开口，μTBS显著更高。
