Taokhampu Nutthawat, Lekatana Hathairat, Palasuk Jadesada
Laem Chabang Hospital, 188/36, Moo 6, Sukhumvit Road, Thung Sukhla, Si Racha District, Chon Buri, 20230, Thailand.
Department of Restorative Dentistry, Faculty of Dentistry, Naresuan University, Phitsanulok, 65000, Thailand.
BMC Oral Health. 2025 May 24;25(1):789. doi: 10.1186/s12903-025-06201-0.
The provisional 3D-printed methacrylate resin is progressively used due to its superior accuracy and durability compared to traditionally fabricated provisional restorations. However, chairside modifications remain necessary to enhance marginal adaptation, esthetics, and functionality. This study aimed to evaluate the effect of surface treatments and repair materials on shear bond strength (SBS) of aged provisional 3D-printed methacrylate resin.
A total of 120 specimens (20 mm in diameter and 15 mm in height) were designed, printed using a DLP resin-based 3D printer, and aged by thermocycling for 1,500 cycles. Specimens (n = 10) were divided into four groups based on surface treatments: no surface treatment (negative control, NC), airborne particle abrasion (AlO), universal adhesive application (Adh), and airborne particle abrasion followed by the application of universal adhesive (AlO/Adh). Then, specimens were bonded using one of three repair materials: polymethyl methacrylate (PMMA), bis-acryl composite, and flowable composite. After 24 h, SBS was tested using a universal testing machine at a crosshead speed of 0.5 mm/min. Failure modes were examined using a stereomicroscope (20× magnification). The data were analyzed using the Kruskal-Wallis test, followed by Dunn's test with a Bonferroni correction for multiple comparisons (p < 0.05).
Flowable composite exhibited the highest SBS when aged provisional 3D-printed methacrylate resin was treated with AlO/Adh, AlO, and Adh, respectively, with no significant difference among these groups (p > 0.05). The lowest SBS was observed in NC, regardless of repair materials. Failure mode analysis was predominantly adhesive failure in the NC group, whereas cohesive and mixed failures were more common in the groups treated with AlO, Adh, and AlO/Adh, which were associated with improved bond strength.
To achieve the optimal SBS between aged provisional 3D-printed methacrylate resin and repair/reline materials, surface preparation with Al₂O₃/Adh, Al₂O₃, or Adh followed by flowable composite is recommended.
In clinical settings where airborne particle abrasion is unavailable or impractical, applying universal adhesive followed by flowable composite provides reliable bond strength to aged 3D-printed methacrylate resin. However, omitting surface treatment entirely is not recommended due to the significantly reduced bond strength.
与传统制作的临时修复体相比，临时3D打印甲基丙烯酸酯树脂因其更高的精度和耐用性而被逐渐采用。然而，仍需要在椅旁进行修改以提高边缘适应性、美观性和功能性。本研究旨在评估表面处理和修复材料对老化的临时3D打印甲基丙烯酸酯树脂剪切粘结强度（SBS）的影响。
共设计120个样本（直径20毫米，高15毫米），使用基于数字光处理（DLP）树脂的3D打印机打印，并通过热循环老化1500次。样本（n = 10）根据表面处理分为四组：无表面处理（阴性对照，NC）、空气颗粒研磨（AlO）、涂抹通用粘结剂（Adh）以及空气颗粒研磨后涂抹通用粘结剂（AlO/Adh）。然后，使用三种修复材料之一进行粘结：聚甲基丙烯酸甲酯（PMMA）、双丙烯酸复合材料和流动复合材料。24小时后，使用万能试验机以0.5毫米/分钟的十字头速度测试SBS。使用体视显微镜（20倍放大）检查失败模式。数据采用Kruskal-Wallis检验进行分析，随后进行Dunn检验，并采用Bonferroni校正进行多重比较（p < 0.05）。
当老化的临时3D打印甲基丙烯酸酯树脂分别用AlO/Adh、AlO和Adh处理时，流动复合材料表现出最高的SBS，这些组之间无显著差异（p > 0.05）。无论使用何种修复材料，NC组的SBS最低。失败模式分析显示，NC组主要为粘结失败，而在AlO、Adh和AlO/Adh处理的组中，内聚和混合失败更为常见，这与粘结强度的提高有关。
为了在老化的临时3D打印甲基丙烯酸酯树脂与修复/重衬材料之间实现最佳的SBS，建议先用Al₂O₃/Adh、Al₂O₃或Adh进行表面处理，然后使用流动复合材料。
在无法进行或不适合进行空气颗粒研磨的临床环境中，先涂抹通用粘结剂再使用流动复合材料可为老化的3D打印甲基丙烯酸酯树脂提供可靠的粘结强度。然而，由于粘结强度显著降低，不建议完全省略表面处理。
