Produção Nacional
Revisado por pares
Biomechanical Evaluation of Platform Switching: Different Mismatch Sizes, Connection Types, and Implant Protocols
2014; Wiley; Volume: 85; Issue: 9 Linguagem: Inglês
10.1902/jop.2014.130633
ISSN1943-3670
AutoresRoberto Sales e Pessoa, Fábio Bezerra, Ravel Sousa, Jos Vander Sloten, Márcio Zaffalon Casati, Siegfried Jaecques,
Tópico(s)Tissue Engineering and Regenerative Medicine
ResumoBackground: It is not yet well understood to what extent different implant–abutment mismatch sizes and implant–abutment connection types may influence the peri‐implant biomechanical environment of implants in different clinical situations. Methods: Computed tomography–based finite element models comprising a maxillary central incisor socket and 4.5 × 13 mm outer‐diameter implants with external and internal hex connection types were constructed. The abutments were designed with diameters of 3.5 mm (platform switching [PS] with 1 mm of diametral mismatch [PS − 1]), 4.0 mm (PS with 0.5 mm of diametral mismatch [PS − 0.5]), and 4.5 mm (conventional matching implant–abutment design [CD]). Analysis of variance at the 95% confidence interval was used to evaluate peak equivalent strain (EQV strain) in the bone, bone volume affected by a strain >4,000 με (EQV strain >4,000 με), the peak von Mises stress (EQV stress) in abutment screw, and the bone–implant relative displacement. Results: Similar bone strain levels (EQV strain and EQV strain >4,000 με) were encountered in PS − 1, PS − 0.5, and CD models for immediately placed implants, independent of the connection type. For immediately loaded implants, slightly smaller peak EQV strain and EQV strain >4,000 με were found for PS − 1. However, for both connection types in osseointegrated models, the higher the mismatch size, the lesser the amount of strain found. Conclusions: The increase in mismatch size of PS configuration results in a significant decrease of strain levels in bone for osseointegrated implants, principally for external hex connections. No significant effect of PS could be noted in immediately placed implants.
Referência(s)