Singh Sougaijam Vijay, Gupta Saurabh, Sharma Deepak, Pandit Nymphea, Nangom Aruna, Satija Harsha
Department of Conservative Dentistry and Endodontics, DAV (c) Dental College and Hospital, Yamuna Nagar, Haryana, India.
Department of Conservative Dentistry and Endodontics, Jaipur Dental College and Hospital, Jaipur, Rajasthan, India.
J Conserv Dent. 2015 May-Jun;18(3):196-9. doi: 10.4103/0972-0707.157242.
Adequate bone support is an essential factor to avoid undue stress to the tooth. This is important when the tooth is endodontically treated and requires a post. The purpose of the present finite element (FE) analysis study was to evaluate the stress distribution of post on endodontically treated tooth with reduced alveolar bone height support and after bone augmentation. The null hypothesis was that there is no difference between the stress distribution of post on endodontically treated teeth with reduced alveolar bone height support and after alveolar bone height augmented using bone graft substitute.
The three-dimensional model was fabricated using ANSYS Workbench version 13.0 software to represent an endodontically treated mandibular second premolar restored with a full ceramic crown restoration and was analyzed using FE analysis. A load of 300N at an angle of 60° to the vertical was applied to the triangular ridge of the buccal cusp in a buccolingual plane. The stresses on the tooth with normal alveolar bone height, reduced alveolar bone height, and after bone augmentation because of reduced bone height were calculated using von misses stresses.
A maximum stress value of 136.04 MPa was observed in dentin with an alveolar bone height of 4 mm from the cemento-enamel junction (CEJ). However, after 2 mm of alveolar bone augmentation, the stress value was 104.32 MPa, which was comparable to the stress value of 105.56 observed with the normal bone height of 2 mm from the CEJ.
Similar values of stresses were observed in teeth with normal and augmented bone height. Increased stresses were observed with alveolar bone loss of 4 mm from the CEJ.
充足的骨支持是避免牙齿承受过度应力的关键因素。当牙齿接受根管治疗并需要桩时，这一点尤为重要。本有限元（FE）分析研究的目的是评估在牙槽骨高度支持降低和骨增量后，根管治疗牙齿上桩的应力分布。原假设是，在牙槽骨高度支持降低的根管治疗牙齿与使用骨替代物增加牙槽骨高度后的应力分布之间没有差异。
使用ANSYS Workbench 13.0软件构建三维模型，以代表用全瓷冠修复的根管治疗下颌第二前磨牙，并使用有限元分析进行分析。在颊舌平面上，以与垂直方向成60°角的300N载荷施加于颊尖的三角嵴上。使用冯米塞斯应力计算正常牙槽骨高度、牙槽骨高度降低以及因骨高度降低而进行骨增量后的牙齿应力。
在距牙骨质-釉质界（CEJ）4mm牙槽骨高度的牙本质中观察到最大应力值为136.04MPa。然而，在牙槽骨增加2mm后，应力值为104.32MPa，这与距CEJ 2mm正常骨高度时观察到的105.56应力值相当。
在骨高度正常和增加的牙齿中观察到相似的应力值。在距CEJ牙槽骨丧失4mm时观察到应力增加。
