UNASSIGNED: The teeth were randomly assigned to either SLM or SLA group. Preoperative cone-beam computed tomography (CBCT) and a three-dimensional (3D) scanner were used to establish the 3D root canal system and the accurate occlusal models of the teeth. The virtual access to the canal access was designed using Mimics 19.0 and 3-Matic 11.0. The endodontic access was performed based on either SLM or SLA templates. The accuracy of endodontic preparation was measured in three-dimensions by calculating deviations from planned accesses. The template height and tooth substance loss rates in each group were measured.
UNASSIGNED: SLM-guided templates have a low average deviation at the entry point and apical portion of the bur of total posterior teeth (including premolars and molars) and individual molars (P < 0.05). Moreover, there was a significant difference in angular deviations and height of template in total posterior teeth and individual molars (P < 0.05). The mean substance loss rate of the SLA group was slightly greater than that of the SLM group, but the difference was not statistically (P > 0.05).
UNASSIGNED: SLM-guided endodontics provides a more predictable and precise location of root canal orifice for the treatment of posterior teeth.
■牙齿被随机分配到SLM或SLA组。术前使用锥形束计算机断层扫描(CBCT)和三维(3D)扫描仪建立了3D根管系统和牙齿的准确咬合模型。使用Mimics19.0和3-Matic11.0设计了运河通道的虚拟通道。基于SLM或SLA模板进行牙髓接入。通过计算与计划访问的偏差,在三维中测量了牙髓制备的准确性。测量各组的模板高度和牙齿物质损失率。
■SLM引导的模板在全后牙(包括前磨牙和磨牙)和个体磨牙的进入点和顶端部分的平均偏差较低(P<0.05)。此外,全后牙和单个磨牙的角度偏差和模板高度差异有统计学意义(P<0.05)。SLA组的平均物质损失率略大于SLM组,但差异无统计学意义(P>0.05)。
■SLM引导的牙髓疗法为治疗后牙提供了更可预测和精确的根管口位置。