A new approach for Y-TZP surface treatment: evaluations of roughness and bond strength to resin cemen.

OBJECTIVE: This study aims to evaluate the effect of sonochemical treatment on the surface of yttria-stabilized tetragonal zirconia (Y-TZP) before and after the final sintering. MATERIAL AND METHODS: Twenty-eight Y-TZP discs were divided into four groups (n=7), according to surface treatment: PRE: pre-sintering sonication with 30% nominal power for 15 min; POS: post-sintering sonication with 30% nominal power for 15 min; JAT: air abrasion with 50-µm alumina particles; and CON: control group with no treatment. The POS and JAT groups were sintered before sonication and the PRE group after sonication. Surface roughness was analyzed using confocal microscopy, after which resin cement cylinders were placed on the surface of the Y-TZP discs and subjected to mechanical microshear bond strength test until fracture. Surface roughness and microshear bond strength values underwent ANOVA and the Tukey tests. RESULTS: The surface roughness values for the PRE group (299.91 nm) and the POS group (291.23 nm) were not significantly different (p≥0.05), statistically, and the surface roughness value of the JAT group (925.21 nm) was higher than those of PRE and POS (p=0.007) groups. The mechanical microshear bond strength test showed that there was no statistically significant difference between the groups (p=0.08). CONCLUSIONS: Therefore, the results showed that sonochemical treatment modifies the Y-TZP surface and is similar to the well-established sandblasting surface treatment regarding the strength of the bond with the resin cement.

A new approach for Y-TZP surface treatment: evaluations of roughness and bond strength to resin cemen

Abstract Objective This study aims to evaluate the effect of sonochemical treatment on the surface of yttria-stabilized tetragonal zirconia (Y-TZP) before and after the final sintering. Material and Methods Twenty-eight Y-TZP discs were divided into four groups (n=7), according to surface treatment: PRE: pre-sintering sonication with 30% nominal power for 15 min; POS: post-sintering sonication with 30% nominal power for 15 min; JAT: air abrasion with 50-μm alumina particles; and CON: control group with no treatment. The POS and JAT groups were sintered before sonication and the PRE group after sonication. Surface roughness was analyzed using confocal microscopy, after which resin cement cylinders were placed on the surface of the Y-TZP discs and subjected to mechanical microshear bond strength test until fracture. Surface roughness and microshear bond strength values underwent ANOVA and the Tukey tests. Results The surface roughness values for the PRE group (299.91 nm) and the POS group (291.23 nm) were not significantly different (p≥0.05), statistically, and the surface roughness value of the JAT group (925.21 nm) was higher than those of PRE and POS (p=0.007) groups. The mechanical microshear bond strength test showed that there was no statistically significant difference between the groups (p=0.08). Conclusions Therefore, the results showed that sonochemical treatment modifies the Y-TZP surface and is similar to the well-established sandblasting surface treatment regarding the strength of the bond with the resin cement.

Restauração estética de dentes anteriores escurecidos com sistema / Componeer Esthetic restoration of darkened anterior teeth using the Componeer system

Como a Odontologia minimamente invasiva tornou-se mais conhecida, diferentes tratamentos estéticos também foram colocados em prática. Um novo tratamento restaurador estético para dentes anteriores é a técnica semidireta usando facetas pré-fabricadas de resina nano-híbrida. Trata-se de um método restaurador alternativo e minimamente invasivo que apresenta confiabilidade estética e cosmética, além de ser uma solução financeiramente vantajosa graças à diminuição de etapas, como procedimentos de moldagem e trabalho laboratorial. Assim, o objetivo deste artigo é demonstrar a utilização de sistema Componeer para o restabelecimento estético de dentes anteriores escurecidos.

As minimally invasive Dentistry has become more known, new aesthetics treatments are also being used. One new esthetic restorative treatment for anterior teeth is the semi-direct technique using pre-fabricated nanohybrid resin composite veneers. It is a minimally invasive alternative restorative method that presents cosmetic and aesthetic reliability and it is a financially advantageous solution due to reduction of stages such as impression procedures and laboratory work. So the purpose of this article is to demonstrate the use of the Componeer system to reestablish the aesthetics of anterior darkened teeth.