A comparative evaluation of vertical marginal fit of provisional crowns fabricated by computer-aided design/computer-aided manufacturing technique and direct (intraoral technique) and flexural strength of the materials: An in vitro study

Objetivo: Revisar acerca do efeito da fumaça do cigarro, associada ou não à escovação, na rugosidade superficial e na microdureza de uma cerâmica vítrea de dissilicato de lítio “Computer-Aided Design/Computer-Aided Manufacturing” (CAD/CAM). Métodos: Pesquisaram-se os descritores cadastrados no MeSH “lithium disilicate”, “smoking”, “CAD CAM”, “brushing”, “rough”, “hardness”, combinados entre si pelo operador booleano “AND”, na base de dados PubMed nos últimos 5 anos. Resultados: De acordo com a pesquisa, foram encontrados 625 artigos e selecionados 12 estudos in vitro. 5 estudos concluíram que as restaurações cerâmicas CAD/CAM apresentaram estabilidade de cor e de rugosidade da superfície, após escovação simulada e termociclagem. 4 estudos observaram que a escovação simulada e algumas bebidas aumentaram significativamente a rugosidade superficial da cerâmica de dissilicato de lítio. 3 estudos inferiram que a rugosidade superficial e a microdureza podem ser influenciadas pelos tratamentos de superfícies. Considerações finais: As cerâmicas de dissilicato de lítio CAD/CAM possuem propriedades satisfatórias em relação a sua resistência e estética, após exposição à fumaça do cigarro, associada ou não com a escovação.

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Evaluation of the Adhesion of a Novel Design of Veneers to Dental Materials

Revista de Chimie ◽

10.37358/rc.17.9.5838 ◽

2017 ◽

Vol 68 (9) ◽

pp. 2125-2128

Author(s):

Alexandra Cristina Maroiu ◽

Cosmin Sinescu ◽

Radu Negru ◽

Liviu Marsavina ◽

Ioana Delia Bretean ◽

...

Keyword(s):

Computer Aided Design ◽

High Performance ◽

Dental Materials ◽

In Vitro Study ◽

The Novel ◽

Adhesive Properties ◽

Computer Aided ◽

Aided Design ◽

Novel Design

The aim of this in vitro study was to assess a new design that, to our knowledge, we have introduced (patent pending) for indirect dental veneers. Their effect on the retention and adhesive properties at their interfaces have been studied. Fourteen high performance polymeric (PEEK) dental veneers have been elaborated using a computer-aided-design (CAD) software and then milled using a computer-aided-machine (CAM). They were divided in two experimental groups: seven classical veneers with a liniar marginal contour and seven dental veneers with the novel proposed sinusoidal marginal design. All the samples have been bonded to polymeric blocks that had the vestibular face prepared in a specific way for each group. The values of the retention and adhesive forces were tested in vitro by applying bending forces on the incisal edge of the veneers, from the oral to the vestibular direction. A 50% increase of the values of these forces for the novel design with regard to the classical one has been demonstrated through the study.

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Misfit evaluation of dental implant-supported metal frameworks manufactured with different techniques: Photoelastic and strain gauge measurements

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411916676192 ◽

2016 ◽

Vol 230 (12) ◽

pp. 1106-1116 ◽

Cited By ~ 1

Author(s):

Roberto Montanini ◽

Michele Scafidi ◽

Giorgio Staiti ◽

Antonia Marcianò ◽

Leonardo D’Acquisto ◽

...

Keyword(s):

Computer Aided Design ◽

Cost Benefit ◽

Resin Cement ◽

Computer Aided Manufacturing ◽

Significant Difference ◽

Computer Aided ◽

Manufacturing Techniques ◽

Aided Design ◽

Supported Metal

This study aims to compare in-vitro the fitting accuracy of implant-supported metal frameworks used for full-arch orthodontic restoration. The hypotheses tested were as follows: (1) for a fixed implant morphology, strains developed within the framework depend on how the framework had been fabricated and (2) stresses transferred to the implant–bone interface are related to the amount of framework misfit. Metal frameworks were fabricated using four different manufacturing techniques: conventional lost-wax casting, resin cement luting, electrospark erosion, and computer-aided design/computer-aided manufacturing milling. Each framework was instrumented with three strain gauges to measure strains developed because of prosthetic misfit, while quantitative photoelastic analysis was used to assess the effect of misfit at the implant–resin interface. All the tested frameworks presented stress polarization around the fixtures. After screw tightening, significantly greater strains were observed in the lost-wax superstructure, while the lowest strains were observed in the luted framework, demonstrating consistent adaptation and passive fitting. No significant difference in stress distribution and marginal fit was found for bars fabricated by either computer-aided design/computer-aided manufacturing or spark erosion. This study suggested that, in spite of known limitations of in-vitro testing, direct luting of mesostructures and abutments should be the first clinical option for the treatment of complete edentulism, ensuring consistent passive fitting and effective cost–benefit ratio.

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