Ramanujam Padmapriya, Karthikeyan Paul Kevin Abishek, Srinivasan Vignesh, Ulaganathan Selvakarthikeyan, Natanasabapathy Velmurugan, Suresh Nandini
Department of Conservative Dentistry and Endodontics, Sri Venkateswara Dental College and Hospital, Chennai, India.
Department of Conservative Dentistry and Endodontics, Meenakshi Ammal Dental College and Hospital, Meenakshi Academy of Higher Education and Research (Deemed to be a university), Chennai, India.
Restor Dent Endod. 2025 May;50(2):e21. doi: 10.5395/rde.2025.50.e21. Epub 2025 May 21.
This study analyzed the stress distribution in a maxillary central incisor with external cervical resorptive defect restored with different restorative materials under normal masticatory and traumatic loading conditions using finite element analysis.
Cone-beam computed tomography of an extracted intact incisor and created resorptive models (Patel's 3D classification-2Bd and 2Bp) in the maxillary central incisor was performed for finite element models. The 2Bd models were restored either with glass ionomer cement (GIC)/Biodentine (Septodont) or a combination of both with composite resin. 2Bp models were restored externally with a combination technique and internally with root canal treatment. The other model was external restoration with GIC and internal with fiber post. Two masticatory loads were applied at 45˚ to the palatal aspect, and two traumatic loads were applied at 90˚ to the buccal aspect. Maximum von Mises stresses were calculated, and stress distribution patterns were studied.
In 2Bd models, all restorative strategies decreased stress considerably, similar to the control model under all loads. In 2Bp models, the dentin component showed maximum stress at the deepest portion of the resorptive defect, which transfers into the adjacent pulp space. In 2Bp defects, a multilayered restoration externally and root canal treatment internally provides better stress distribution compared to the placement of a fiber post.
Increase in load, proportionally increased von Mises stress, despite the direction or angulation of the load. Multilayered restoration is preferred for 2Bd defects, and using an internal approach of root canal treatment is suggested to restore 2Bp defects.
本研究采用有限元分析方法，分析了在正常咀嚼和创伤载荷条件下，用不同修复材料修复的上颌中切牙伴外源性颈缘吸收缺损时的应力分布情况。
对拔除的完整切牙进行锥形束计算机断层扫描，并在上颌中切牙创建吸收模型（帕特尔3D分类-2Bd和2Bp）以建立有限元模型。2Bd模型用玻璃离子水门汀（GIC）/生物陶瓷（Septodont）或两者与复合树脂的组合进行修复。2Bp模型采用联合技术进行外部修复，并进行根管治疗。另一个模型是用GIC进行外部修复，并用纤维桩进行内部修复。在腭侧45˚施加两种咀嚼载荷，在颊侧90˚施加两种创伤载荷。计算最大冯·米塞斯应力，并研究应力分布模式。
在2Bd模型中，所有修复策略均显著降低了应力，与所有载荷下的对照模型相似。在2Bp模型中，牙本质成分在吸收缺损的最深部位显示出最大应力，并传递到相邻的牙髓腔。在2Bp缺损中，与放置纤维桩相比，外部多层修复和内部根管治疗可提供更好的应力分布。
尽管载荷方向或角度不同，但载荷增加时，冯·米塞斯应力成比例增加。2Bd缺损首选多层修复，建议采用根管治疗的内部方法修复2Bp缺损。
