Efeito dos desenhos de pilares protéticos de conexão cônica na manutenção do torque sob carga cíclica: estudo in vitro
Carregando...
Arquivos
Data
2022-08-23
Autores
Arcas, Felipe Carlos Dias
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Este estudo teve o objetivo de avaliar o comportamento biomecânico de um novo pilar protético dividido em duas peças (P2P) comparado a um pilar padrão de uma peça (P1P), ambos com indicação para coroas unitárias parafusadas de um sistema de implante de conexão cônica, submetidos a ciclagem mecânica. Foram utilizados vinte implantes instalados em cilindros de resina poliacetal e divididos em dois grupos: P1P para restaurações ao nível da plataforma do implante, de conexão cônica anti-rotacional e parafuso passante e P2P para restaurações ao nível de tecidos, constituído de duas peças, uma base sólida (P2P-B), de conexão cônica rotacional e um pilar sobre a base (P2P-P), de conexão hexagonal interna anti-rotacional e parafuso passante. Os corpos de prova foram testados antes e após a ciclagem mecânica (200N a 4Hz por 1x106 ciclos) através da verificação da manutenção do torque em N.cm por um torquímetro digital e da análise das micro fendas em m na conexão implante-pilar por microscopia. O grupo P1P apresentou redução significativa no torque de remoção pós-ciclagem 10,57 (3,63) comparado ao torque pré-ciclagem 31,63 (0,80) e torque de remoção inicial 26,48 (1,60). O grupo P2P-B apresentou aumento significativo no torque de remoção pós-ciclagem 41,00 (8,64), comparado ao torque pré-ciclagem 31,10 (0,62) e torque de remoção inicial 30,12 (2,08), sua parte superior P2P-P apresentou redução significativa no torque de remoção pós-ciclagem 14,85 (2,06), comparado ao torque pré-ciclagem 21,06 (0,50), porém não apresentou diferença significativa com o torque de remoção inicial 15,51 (1,18). Na avaliação microscópica, a conexão implante-pilar nos dois grupos apresentaram micro fendas iniciais reduzidas, P1P 4,71 (2,12) e P2P-B 3,95 (2,02) as quais tiveram redução significativa após a ciclagem, P1P 0,006 (0,001) e P2P-B 0,005 (0,001). P2P apresentou comportamento biomecânico superior ao P1P nos valores de torque pós-ciclagem, nos vários momentos comparados, suportando seu uso para coroas unitárias. A interface de conexão de ambos os pilares exibiram micro fendas reduzidas sob microscopia, as quais foram praticamente eliminadas com o acoplamento produzido pela ciclagem mecânica.
This study aimed to evaluate the biomechanical behavior of a new two-piece split prosthetic abutment (P2P) compared to a standard one-piece abutment (P1P), both indicated for screw-retained single crowns of a conical connection implant system, subjected to mechanical cycling. Twenty implants installed in polyacetal resin cylinders were used and divided into two groups: P1P for implant platform-level restorations, with an anti-rotational conical connection and through screw, and P2P for tissue-level restorations, consisting of two pieces, a solid base (P2P-B), with a rotational conical connection, and an abutment on the base (P2P-P), with an internal hexagonal anti-rotational connection and through screw. The specimens were tested before and after mechanical cycling (200 N at 4 Hz for 1x106 cycles) by checking the torque maintenance in N.cm by a digital torque meter and analyzing the microgaps in µm in the implant-abutment connection by microscopy. The P1P group showed a significant reduction in post-cycling removal torque 10.57 (±3.63) compared to precycling torque 31.63 (±0.80) and initial removal torque 26.48 (±1.60). The P2P-B group showed significant increase in post-cycling removal torque 41.00 (±8.64), compared to pre-cycling torque 31.10 (±0.62) and initial removal torque 30.12 (±2.08), its top the P2P-P showed significant decrease in post-cycling removal torque 14.85 (±2.06), compared to pre-cycling torque 21.06 (±0.50), but showed no significant difference with the initial removal torque 15.51 (±1.18). In the microscopic evaluation, the implant-abutment connection in both groups showed reduced initial microgaps, P1P 4.71 (±2.12) and P2P-B 3.95 (±2.02), which had significant reduction after cycling, P1P 0.006 (±0.001) and P2P-B 0.005 (±0.001). The P2P showed superior biomechanical behavior than the P1P abutment in post-cycling torque values at the various comparative times, supporting its use for single crowns. The connection interface of both abutments exhibited reduced microgaps under microscopy, which were practically eliminated with the coupling produced by mechanical cycling.
This study aimed to evaluate the biomechanical behavior of a new two-piece split prosthetic abutment (P2P) compared to a standard one-piece abutment (P1P), both indicated for screw-retained single crowns of a conical connection implant system, subjected to mechanical cycling. Twenty implants installed in polyacetal resin cylinders were used and divided into two groups: P1P for implant platform-level restorations, with an anti-rotational conical connection and through screw, and P2P for tissue-level restorations, consisting of two pieces, a solid base (P2P-B), with a rotational conical connection, and an abutment on the base (P2P-P), with an internal hexagonal anti-rotational connection and through screw. The specimens were tested before and after mechanical cycling (200 N at 4 Hz for 1x106 cycles) by checking the torque maintenance in N.cm by a digital torque meter and analyzing the microgaps in µm in the implant-abutment connection by microscopy. The P1P group showed a significant reduction in post-cycling removal torque 10.57 (±3.63) compared to precycling torque 31.63 (±0.80) and initial removal torque 26.48 (±1.60). The P2P-B group showed significant increase in post-cycling removal torque 41.00 (±8.64), compared to pre-cycling torque 31.10 (±0.62) and initial removal torque 30.12 (±2.08), its top the P2P-P showed significant decrease in post-cycling removal torque 14.85 (±2.06), compared to pre-cycling torque 21.06 (±0.50), but showed no significant difference with the initial removal torque 15.51 (±1.18). In the microscopic evaluation, the implant-abutment connection in both groups showed reduced initial microgaps, P1P 4.71 (±2.12) and P2P-B 3.95 (±2.02), which had significant reduction after cycling, P1P 0.006 (±0.001) and P2P-B 0.005 (±0.001). The P2P showed superior biomechanical behavior than the P1P abutment in post-cycling torque values at the various comparative times, supporting its use for single crowns. The connection interface of both abutments exhibited reduced microgaps under microscopy, which were practically eliminated with the coupling produced by mechanical cycling.
Descrição
Palavras-chave
Implantes dentários, Projeto do implante dentário-pivô, Troca da plataforma do implante dentário, Torque, Falha de prótese, Dental implants, Dental implant-abutment design, Dental implant platformswitching, Torque, Prosthesis failure