Department of Adhesive Dentistry, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20 Fujimi, Chiyoda-ku, Tokyo, 102-8159, Japan.
Odontology. 2021 Jul;109(3):585-595. doi: 10.1007/s10266-020-00578-w. Epub 2021 Jan 2.
The development of dental CAD/CAM system has made metal-free ceramic restorations more available to patients. Silane coupling treatment is an essential clinical process to achieve reliable and good adhesion with silica-based indirect restoratives. However, long-term water-storage causes the hydrolysis of silane coupling agents and decreases the bond strength. The aim of this study was to examine the effect of additional treatments including photochemical treatments on silane coupling performance in ceramic restorations. The influence of water-storage periods (1d: one day, 1m: one month, and 3m: three months) for the silanized surface of CAD/CAM ceramic restorations was also investigated. In addition, bonding reliability was evaluated as a qualitative measure in order to characterize the bond strength of CAD/CAM restorations. The micro-tensile bond strength (μ-TBS) was measured to explore the benefits of additional photochemical treatments (UV: ultraviolet and VL: visible light irradiations) on silanized surfaces, compared to non-additional treated (CO) and dry heating (DR) conditions. In the CO specimens, μ-TBS decreased in the order of 1d > 1m > 3m. However, in DR, UV, and VL additional treatments, no significant differences could be observed in the 1d, 1m, and 3m groups. The Weibull modulus and 10% failure probability values of the UV and VL specimens were inclined to be significantly greater than those of CO specimens, regardless of the water-storage period. These findings reveal that additional photochemical treatments had a successful effect to improve the bond strength and bonding reliability of the CAD/CAM restorations, when compared to CO and DR conditions.
牙科 CAD/CAM 系统的发展使得无金属陶瓷修复体更能为患者所接受。硅烷偶联处理是实现与基于二氧化硅的间接修复体可靠和良好黏附的必要临床过程。然而，长期水储存会导致硅烷偶联剂水解，并降低结合强度。本研究旨在研究包括光化学处理在内的附加处理对陶瓷修复体中硅烷偶联性能的影响。还研究了水储存期（1d：一天，1m：一个月，3m：三个月）对 CAD/CAM 陶瓷修复体硅烷化表面的影响。此外，作为定性测量评估了结合可靠性，以表征 CAD/CAM 修复体的结合强度。测量了微拉伸结合强度（μ-TBS），以探讨附加光化学处理（UV：紫外线和 VL：可见光照射）对硅烷化表面的益处，与非附加处理（CO）和干热（DR）条件相比。在 CO 标本中，μ-TBS 按 1d>1m>3m 的顺序降低。然而，在 DR、UV 和 VL 附加处理中，在 1d、1m 和 3m 组中均未观察到显著差异。无论水储存期如何，UV 和 VL 标本的韦布尔模数和 10%失效概率值都倾向于显著大于 CO 标本。这些发现表明，与 CO 和 DR 条件相比，附加光化学处理对 CAD/CAM 修复体的结合强度和结合可靠性具有成功的效果。
