Wu Bin-Zhang, Yang Wen, Liu Ming-Yue, Ma Fei-Fei, Jiao Hai, Sun Feng
First Clinical Division, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Beijing, China.
First Clinical Division, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Beijing, China.
J Dent. 2025 Sep;160:105876. doi: 10.1016/j.jdent.2025.105876. Epub 2025 Jun 3.
To propose a novel marker-free cusp-and-surface registration (CSR) technique for dynamic computer-assisted implant surgery (dCAIS) and to evaluate its accuracy in vitro.
Forty implants were inserted into twenty 3D-printed models designed to simulate maxillary anterior partial edentulism, using a dynamic navigation system that employed either the CSR or cusp registration (CR) technique. The CR group employed six reference points on six teeth adjacent to the edentulous ridge as reference structures. The CSR group required only four reference teeth, one reference point per tooth, and four to five reference surfaces. The evaluation included linear and angular deviations between the planned and actual implant locations. The registration times for CSR and CR were documented and analyzed. Group comparisons were conducted using the independent sample t-test or the Mann-Whitney U test.
The CSR group yielded average entry, apex, and axis deviations of 0.51 ± 0.23 mm, 0.59 (0.45-0.71) mm, and 2.22 ± 0.65°, while the corresponding deviations of the CR group were 0.55 ± 0.31 mm, 0.60 (0.46-0.82) mm, and 1.80 ± 0.79°, respectively (P > 0.05). No significant differences between the groups were observed in angular or linear deviations, except for the apex mesio-distal deviation. The CSR group showed a considerable reduction in apex mesio-distal deviation relative to the CR group [0.17 (0.10-0.23) vs. 0.31 (0.19-0.41) mm; P = 0.006]. Registration duration differed significantly between groups, with an average length of 3.48 ± 0.77 min for the CR group and 4.60 ± 0.65 min for the CSR group (P < 0.05).
The CSR method, using four reference teeth, provides in vitro accuracy comparable to that of the CR technique, which employs six reference teeth, thus decreasing the required number of remaining reference teeth for effective registration.
Considering the limitations of this in vitro study, the CSR strategy provides accuracy comparable to the more conventional marker-free registration approach while reducing the number of remaining reference teeth needed. The CSR method shows promise as an effective registration technique in dCAIS, potentially expanding the scope of marker-free registration.
提出一种用于动态计算机辅助种植手术（dCAIS）的新型无标记尖点与表面配准（CSR）技术，并在体外评估其准确性。
使用采用CSR或尖点配准（CR）技术的动态导航系统，将40枚种植体植入20个设计用于模拟上颌前部部分牙列缺失的3D打印模型中。CR组在与无牙嵴相邻的6颗牙齿上使用6个参考点作为参考结构。CSR组仅需要4颗参考牙，每颗牙一个参考点，以及4至5个参考表面。评估包括计划种植体位置与实际种植体位置之间的线性和角度偏差。记录并分析CSR和CR的配准时间。使用独立样本t检验或Mann-Whitney U检验进行组间比较。
CSR组的平均入口、根尖和轴线偏差分别为0.51±0.23 mm、0.59（0.45 - 0.71）mm和2.22±0.65°，而CR组的相应偏差分别为0.55±0.31 mm、0.60（0.46 - 0.82）mm和1.80±0.79°（P>0.05）。除根尖近远中偏差外，两组在角度或线性偏差方面未观察到显著差异。与CR组相比，CSR组的根尖近远中偏差显著减小[0.17（0.10 - 0.23）对0.31（0.19 - 0.41）mm；P = 0.006]。两组之间的配准持续时间存在显著差异，CR组的平均时长为3.48±0.77分钟，CSR组为4.60±0.65分钟（P<0.05）。
使用4颗参考牙的CSR方法在体外提供了与使用6颗参考牙的CR技术相当的准确性，从而减少了有效配准所需的剩余参考牙数量。
考虑到这项体外研究的局限性，CSR策略在减少所需剩余参考牙数量的同时，提供了与更传统的无标记配准方法相当的准确性。CSR方法有望成为dCAIS中一种有效的配准技术，可能扩大无标记配准的范围。
