João Fernando Carrijo Queiroz, DDS, São Paulo State University (UNESP), School of Dentistry, Araraquara, São Paulo, Brazil.
Larissa Franco Amaro, graduate student, São Paulo State University (UNESP), School of Dentistry, Araraquara, São Paulo, Brazil.
Oper Dent. 2024 Sep 1;49(5):531-539. doi: 10.2341/23-030-L.
Although at-home bleaching can recover the optical properties of stained CAD-CAM monolithic materials, little is known about its impact on their surface and mechanical properties, especially when successive sessions are performed. This study evaluated the effect of successive at-home bleaching sessions on the microhardness, roughness, topography, biaxial flexural strength (BFS), and reliability of CAD-CAM monolithic materials. Disks from Lava Ultimate (LU), Vita Enamic (VE), and IPS Empress CAD (EMP) were fabricated and submitted to up to three bleaching sessions. At-home bleaching was performed with 10% carbamide peroxide, and each session consisted of one application for 10 hours/day for 14 days. The analyses of the aforementioned parameters were assessed before and after the first, second, and third bleaching sessions, except for BFS, which was evaluated at baseline and after the third session. The Weibull modulus was calculated from the BFS data. The microhardness of the three materials as well as the roughness of LU were not affected by the sessions, whereas the roughness of VE and EMP increased from the second session. All materials displayed topographic changes, which became more pronounced with the increase in the number of sessions. Although bleaching decreased the BFS of the materials, it did not adversely affect their reliability. Successive at-home bleaching sessions with the protocol used in the present study cannot be considered a safe procedure for the materials evaluated.
尽管家庭漂白可以恢复染色 CAD-CAM 整体材料的光学性能，但对于其表面和机械性能的影响却知之甚少，尤其是当进行连续的治疗时。本研究评估了连续家庭漂白治疗对 CAD-CAM 整体材料的显微硬度、粗糙度、形貌、双向弯曲强度（BFS）和可靠性的影响。从 Lava Ultimate（LU）、Vita Enamic（VE）和 IPS Empress CAD（EMP）中制备圆盘，并进行多达三次的漂白治疗。家庭漂白使用 10％过氧脲，每次治疗包括每天应用 10 小时，共 14 天。在第一次、第二次和第三次漂白治疗前后评估了上述参数的分析，BFS 除外，它在基线和第三次治疗后进行评估。从 BFS 数据计算威布尔模量。三种材料的显微硬度以及 LU 的粗糙度不受治疗的影响，而 VE 和 EMP 的粗糙度从第二次治疗开始增加。所有材料均显示出形貌变化，随着治疗次数的增加，变化更加明显。尽管漂白降低了材料的 BFS，但并未对其可靠性产生不利影响。在本研究中使用的方案中进行连续的家庭漂白治疗不能被认为是评估材料的安全程序。
