Microscopic evaluation of implant platform adaptation with UCLA-type abutments: in vitro study

Abstract

ResumoIntrodução: O ajuste entre a prótese e o implante é fundamental para determinar a longevidade do tratamento e manutenção do osso periimplantar. Objetivo: Avaliar o desajuste vertical entre diferentes infraestruturas metálicas e plataforma dos implantes, a fim de fornecer informação, para auxiliar na escolha do metal a ser utilizado. Material e método: O estudo utilizou componentes do tipo UCLA (N=40), com antirrotacional, foram divididos da seguinte forma: componentes usinados em titânio (n=10), componentes fundidos em titânio (n=10), níquel-cromo-titânio-molibdênio (n=10) e em níquel-cromo (n=10). Após o torque, as amostras foram analisados em estereomicroscópio. Para caracterização em MEV, foram utilizadas as amostras mais representativas, com maior e menor desajuste vertical. Resultado: Os dados foram analisados por média e desvio padrão e submetidos ao teste ANOVA ONE way, onde os grupos foram estatisticamente diferentes (p=<0,05), seguido do teste TUKEY. Conclusão: A escolha do infraestrutura influencia no valor do desajuste vertical, sendo que o grupo usinado em Ti apresentou o menor valor de desajuste, e o grupo fundido em Ni Cr o grupo com maior valor de desajuste vertical.Descritores: Prótese dentária; implante dentário. Abstract Introduction:The fit between abutment and implant is crucial to determine the longevity of implant-supported prostheses and the maintenance of peri-implant bones. Objective: To evaluate the vertical misfit between different abutments in order to provide information to assist abutment selection. Material and method: UCLA components (N=40) with anti-rotational system were divided as follows: components usinated in titanium (n=10) and plastic components cast proportionally in titanium (n=10), nickel-chromium-titanium-molybdenum (n=10) and nickel-chromium (n=10) alloys. All components were submitted to stereomicroscope analysis and were randomly selected for characterization by SEM. Result: Data were analyzed using mean and standard deviation and subjected to ANOVA-one way, where the groups proved to statistically different (p=<0.05), followed by Tukey's test. Conclusion: The selection of material influences the value of vertical misfit. The group machined in Ti showed the lowest value while the group cast in Ni Cr showed the highest value of vertical misfit.

The Influence of Custom-Milled Framework Design for an Implant-Supported Full-Arch Fixed Dental Prosthesis: 3D-FEA Study

“…As reported in the literature, the use of a milled framework may be considered as a promising solution due to the smaller vertical mismatch, ensuring reduced misfit [5,24]. Several studies have used the finite element analysis (FEA) as a tool for the biomechanical evaluation of a full-arch implant prostheses [25][26][27].…”

“…The experimental design can also be milled in zirconia [39]. The literature reports that the use of zirconia or metal for full-arch framework would achieve similar mechanical results for implants and peri-implant tissues, in addition to similar vertical fitting [5,22]. However, as a disadvantage, the constant friction of the zirconia framework with the abutments can increase the metal wear [40].…”

“…This framework design includes the occlusal and lingual cusps of the posterior teeth as part of the structure [1]. Such an approach, together with a CAD/CAM (computer aided design/computer aided manufacturing) facility, enables the development of a better adapted infrastructure with a lower vertical misfit than the prosthetic abutment [4,5]. To investigate the bone-implant system by means of a three-dimensional (3D) analysis, the Finite Element Analysis (FEA) method is commonly used [6].…”