Investigation of structural stress distributions under chewing force by finite element analysis in prosthetic restorations on which apical lesion teeth are abutment

Objective: The aim of this study is to examine the structural stress distributions that occur in the teeth and surrounding tissues due to the chewing forces they are exposed to in cases where teeth with apical lesions are used as abutments, by using finite element analysis and to compare them with healthy teeth. Methods: Three different SEA models were generated, representing the tooth conditions underlying different prosthetic restorations: (a) healthy mandibular premolar tooth, (b) single-crown premolar with lesion-treated and fiber posted and (c) lesion-treated fiber posted premolar tooth which is abutment a three-membered bridge. The occlusal static load on each of the tooth models was applied at a value of 300 N at an angle of 45 degrees to the long axis of the tooth in the lingual inclination of the buccal apex of the tooth. The existing mandibular premolar tooth was formed with supporting tissues in accordance with the average anatomical dimensions of the alveolar bone and periodontal ligament, according to the data in the literature. Results: Equivalent stress values were calculated according to the Von Mises hypothesis, and the stress distributions in the models were evaluated. When a total of 3 different model scenarios are examined, including healthy, lesioned, single crown and bridge abutment tooth models; It was observed that the stresses formed after occlusal load applications were concentrated in similar regions (buccal marjin of the tooth, force applied cusp, cervical and middle third of the root) in all models. Conclusion: It has been defined that there is no significant difference between the stress distributions and values in teeth with periapical lesions, which have different abutments, and they are more unsuccessful than healthy teeth in terms of biomechanics. Keywords: Teeth with lesions, fiber post, metal-supported porcelain, bridge, finite element analysis.