HA018 - Hatton
Área: 10 - Implantodontia - clínica protética

Stress distribution and micro-gap formation at the abutment-implant interface: a three-dimensional finite element analysis
Tonin BSH, He Y, Ye N, Chew HP, Fok A
Odontologia Restauradora - UNIVERSIDADE DE SÃO PAULO - RIBEIRÃO PRETO
Conflito de interesse: Não há conflito de interesse

This study aims to investigate the stress distribution in the prosthetic screw and the formation of micro-gaps at the implant-abutment interface of conical connections with titanium (Ti) and yttrium-stabilized zirconium (Y-TZP) abutments. Three-dimensional finite models of the above implant-abutment connections were created. The analyses were conducted using a screw torque of 20 N.cm and an oblique load at 30º from 10 to 100 N at intervals of 10 N, and from 120 to 280 N at intervals of 20 N. The stress distribution, the micro-gap formation process, and the critical load for bridging of the internal implant space, and the size of the micro-gaps were evaluated. The models showed similar patterns of von Mises stress which was mainly concentrated at the top and in the middle of the screw. For all the models, the implant-abutment contact area decreased with increasing load. Above 140 N, bridging of the internal implant space was found when over 70% of the interfacial area was opened. Under 280 N, more than 90% of the interface had a gap larger than 30 mm.
Overall, this study does not indicate any obvious advantage of Ti or Y-TZP abutments over each other. Although the simulated micro-gaps and bridging of the internal implant space can explain the presence of bacteria detected clinically inside implants, the relationship between bacterial invasion and micro-gaps needs further research.
(Apoio: CAPES  N° 88881-187982/2018-01)

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