J Adhes Dent. 2023 Oct 16;25:211-218. doi: 10.3290/j.jad.b4515527.
This case report presents a direct composite inverse injection technique using a bi-layer clear mini-index fabricated with a digital workflow to restore extensive posterior occlusal cavities in a 13-year-old patient.
After a root canal treatment in the right mandibular first molar and step-wise excavation of deep caries in the left mandibular first molar, the extensive occlusal restorations were digitally designed using CAD software, upon which digital wax-ups were 3D-printed. Bi-layer clear mini-indices consisting of a hard outer plastic layer and an elastic inner silicone layer were prepared from the 3D-printed cast. The bonding surfaces were deproteinized using a 6% sodium hypochlorite solution, and an antioxidant (Clearfil DC Activator; Kuraray Noritake) was utilized to improve the dentin bonding durability of a 2-step self-etch adhesive (Clearfil SE Bond 2; Kuraray Noritake). Subsequently, a highly filled universal-shade flowable resin composite (RC) was incrementally placed into the cavities. To create the final occlusal morphology, the same RC was inversely injected through the opening of the bi-layer indices.
The workflow was feasible, and the occlusal cavities were efficiently restored using the injection technique. Occlusal carving and adjustments of the morphology were not necessary, leading to less chair time. At the 1-year follow-up, the clinical outcome was excellent.
The injection technique with a bi-layer clear mini-index accurately translated the digital wax-ups into large, final restorations. Precise morphology and shortened chair time enhanced patient satisfaction, but at the expense of multiple visits.
本病例报告介绍了一种使用双层透明迷你印模（通过数字化工作流程制作）进行直接复合反注入技术，以修复 13 岁患者的广泛后牙咬合面窝洞。
在对右下颌第一磨牙进行根管治疗和逐步去除左下颌第一磨牙深龋后，使用 CAD 软件对广泛的咬合面修复体进行数字化设计，然后对数字化蜡型进行 3D 打印。双层透明迷你印模由硬外层塑料和弹性内层硅橡胶组成，由 3D 打印的铸件制备而成。使用 6%次氯酸钠溶液对粘结面进行去蛋白处理，并使用抗氧化剂（Clearfil DC Activator；Kuraray Noritake）提高两步自酸蚀粘结剂（Clearfil SE Bond 2；Kuraray Noritake）的牙本质粘结耐久性。随后，将高填充通用色调流动树脂复合材料（RC）逐步填入窝洞内。为了形成最终的咬合形态，通过双层印模的开口将相同的 RC 反向注入。
该工作流程是可行的，并且通过注射技术有效地修复了咬合面窝洞。不需要进行咬合雕刻和形态调整，从而减少了椅旁时间。在 1 年的随访中，临床效果极佳。
使用双层透明迷你印模的注射技术可以将数字化蜡型准确地转化为大型最终修复体。精确的形态和缩短的椅旁时间提高了患者的满意度，但需要多次就诊。
