[Influence of the alveolar bone height on stress distribution of post and core restored maxillary premolar].

ABSTRACT

OBJECTIVE: To investigate the stress distribution of post and core restored maxillary premolar with reduced alveolar bone support. METHODS: Cone-beam CT based 3D finite element models of post and core restored maxillary premolar were established, with 3 different alveolar bone support. Group I (control) simulated a clinical situation without horizontal bone loss. In group II, a horizontal bone loss of 25% and in group III of 50% were simulated. Both cast-metal post and prefabricated-fiber post were used. The influence of the alveolar bone height was investigated through three-dimensional elastic finite element static analyses by comparison of the resulting stress field, under vertical and oblique load. Local stress measures were introduced to allow for the assessment of tooth fracture. RESULTS: The von Mises stress value (vertical/oblique) on dentin were measured as follows group I-gold=22.570/66.354, group I-fiber=16.480/58.103; group II-gold=27.690/95.192, group II-fiber=18.260/68.452; group III-gold=37.363/135.010, group III-fiber=24.291/110.170. CONCLUSION: For post and core restored teeth with horizontal bone loss, the alveolar bone support may affect the stress distribution under vertical and oblique load. Reduction of the alveolar bone support may lead to severely increased stress concentration in the root dentin.