Huang Yun, Wang Jingrong, Zhu Liqing, Liu Liren, Gao Shanshan
State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Heliyon. 2023 Dec 16;10(1):e23283. doi: 10.1016/j.heliyon.2023.e23283. eCollection 2024 Jan 15.
To investigate the effect of different designs of movable parts and prosthetic materials on the stress distribution of supporting tissues in mandibular free end dentition defects using three-dimensional finite element analysis of digital Roach attachments.
A 3D model of a patient with Kennedy class I mandibular edentulous conditions was generated, and twelve prosthesis models were applied, combining two designs of removable parts and six types of CAD/CAM restorative materials with different elastic modulus (conventional zirconia, ultra-translucent zirconia, Polyetheretherketone (PEEK), Lithium disilicate, Nanoceramic resin, and resin composite (Paradigm MZ100, 3 M ESPE)). The stress distribution of abutment periodontal ligament, edentulousmucosa, and junction of attachment were analyzed using finite element analysis.
The stress value of the buccal neck of the periodontal ligament and the maximum compressive stress of the distal periodontal ligament of the design with clasp arms were higher than those without clasp arms, while the stress on the junction of attachment and the displacement of the mucosa in the edentulous area were smaller. Restorative materials with high elastic modulus, such as conventional zirconia and ultra-translucent zirconia, are recommended to be used as the fixed part of Roach attachment.
CAD/CAM Roach attachments with clasp arms are recommended for the protection of mucosal soft tissue. Restorative materials with high elastic modulus, such as conventional zirconia and ultra-translucent zirconia, are recommended as the fixed part of Roach attachment for patients with free end defect of mandibular dentition.
This study provides references for the design with clasp arms and the selection of clinical fixed-movable prosthetic materials. Clinicians should consider the design of attachments and selection of appropriate manufacturing materials carefully to avoid negative impacts on patients' periodontal support tissues.
采用数字化Roach附着体的三维有限元分析，研究活动部件的不同设计和修复材料对下颌游离端牙列缺损支持组织应力分布的影响。
构建一名Kennedy I类下颌无牙患者的三维模型，并应用12个修复体模型，将两种可摘部件设计与六种具有不同弹性模量的CAD/CAM修复材料（传统氧化锆、超透明氧化锆、聚醚醚酮（PEEK）、二硅酸锂、纳米陶瓷树脂和树脂复合材料（Paradigm MZ100，3M ESPE））相结合。使用有限元分析对基牙牙周膜、无牙黏膜和附着体连接处的应力分布进行分析。
有卡环臂设计的牙周膜颊侧颈部应力值和远中牙周膜的最大压应力高于无卡环臂设计，而附着体连接处的应力和无牙区黏膜的位移较小。建议使用具有高弹性模量的修复材料，如传统氧化锆和超透明氧化锆，作为Roach附着体的固定部分。
建议使用带有卡环臂的CAD/CAM Roach附着体来保护黏膜软组织。对于下颌牙列游离端缺损患者，建议使用具有高弹性模量的修复材料，如传统氧化锆和超透明氧化锆，作为Roach附着体的固定部分。
本研究为带卡环臂的设计和临床固定-活动修复材料的选择提供了参考。临床医生应仔细考虑附着体的设计和合适制造材料的选择，以避免对患者牙周支持组织产生负面影响。
