Ntovas Panagiotis, Tavelli Lorenzo, Barmak Basir A, Jung Ronald E, Galarraga-Vinueza Maria-Elisa
Department of Prosthodontics, School of Dental Medicine, Tufts University, Boston, Massachusetts, USA.
Department of Oral Medicine, Infection, and Immunity, Division of Periodontology, Harvard School of Dental Medicine, Boston, Massachusetts, USA.
J Periodontol. 2025 Apr 10. doi: 10.1002/JPER.24-0860.
The aim of this study was to evaluate the effect of surgical guide design and type of blade, in relation to soft tissue thickness, on the accuracy of computer-assisted crown lengthening.
A set of fully dentate anatomic maxilla models was implemented, using 2 types of soft-tissue masks with a mean thickness of 1.5 and 3.5 mm, respectively, to simulate a clinical scenario of altered passive eruption. In total, 5 different gingivectomy techniques were assessed, implementing 3 different types of guidance and 2 different blades. The osteotomy was performed using 2 surgical guide designs. After each operation, the models were scanned and superimposed with the initial virtual design, to evaluate the accuracy of each evaluated approach through a set of linear measurements.
For the gingivectomy as well as for the osteotomy, the mean discrepancy was increased in the presence of increased soft tissue thickness (p < 0.05). The integration of supporting planes led to a decrease in the discrepancy compared to the conventional double guide design for both of the investigated soft-tissue thicknesses (p < 0.05). For the models with the normal soft tissue thickness, a lower mean discrepancy was presented, when a mini blade was used instead of a conventional surgical blade, irrespective of the guide design (p < 0.05).
Computer-assisted crown lengthening can be considered a feasible treatment option. Soft tissue thickness has to be taken into consideration during the design of the surgical template, in order additional support to be provided when it is needed. Surgical templates with integrated supporting planes can increase the accuracy of computer-assisted crown lengthening.
Gingival architecture plays a crucial role in achieving smile harmony. For patients seeking an esthetic smile, periodontal plastic surgery can be a valuable option, as it can improve the harmony between the teeth and the gingiva. Excessive gingiva display can be managed using various treatment approaches, depending on the etiology. When periodontal surgery is a part of the treatment plan, the procedure can be digitally planned using a 3D diagnostic design and seamlessly transferred to the surgical field through a 3D printed surgical template. The present research aimed to evaluate the influence of surgical guide design, gingival thickness, and surgical blade type on the accuracy of the periodontal surgery. Two different designs of surgical templates, providing a different degree of guidance, as well as 2 types of surgical blades were used to simulate the surgical procedure. To evaluate the aforementioned parameters, models with 2 different gingival mask thickness were used. Based to the results of the present study, gingival thickness, surgical template design, and blade type can significantly affect the accuracy of the surgery procedure.
本研究的目的是评估手术导板设计和刀片类型与软组织厚度相关时，对计算机辅助牙冠延长术准确性的影响。
使用一组全口有牙的上颌骨解剖模型，分别采用两种平均厚度为1.5毫米和3.5毫米的软组织模型，以模拟被动萌出改变的临床情况。总共评估了5种不同的牙龈切除术技术，采用3种不同类型的导板和2种不同的刀片。使用两种手术导板设计进行截骨术。每次手术后，对模型进行扫描并与初始虚拟设计叠加，通过一系列线性测量来评估每种评估方法的准确性。
对于牙龈切除术和截骨术，软组织厚度增加时平均差异增大（p<0.05）。对于两种研究的软组织厚度，与传统双导板设计相比，支撑平面的整合导致差异减小（p<0.05）。对于软组织厚度正常的模型，无论导板设计如何，使用微型刀片代替传统手术刀片时平均差异较低（p<0.05）。
计算机辅助牙冠延长术可被视为一种可行的治疗选择。在设计手术模板时必须考虑软组织厚度，以便在需要时提供额外支撑。带有整合支撑平面的手术模板可提高计算机辅助牙冠延长术的准确性。
牙龈结构在实现微笑和谐方面起着关键作用。对于寻求美观笑容的患者，牙周整形手术可能是一个有价值的选择，因为它可以改善牙齿与牙龈之间的和谐。根据病因，可使用各种治疗方法来处理牙龈过度外露的问题。当牙周手术是治疗计划的一部分时，该手术可以通过3D诊断设计进行数字化规划，并通过3D打印的手术模板无缝转移到手术区域。本研究旨在评估手术导板设计、牙龈厚度和手术刀片类型对牙周手术准确性的影响。使用了两种提供不同程度引导的不同设计的手术模板以及两种类型的手术刀片来模拟手术过程。基于本研究的结果，牙龈厚度、手术模板设计和刀片类型可显著影响手术过程的准确性。
