Effect of ceramic materials on the optical properties of porcelain veneers for tetracycline-stained teeth / 华西口腔医学杂志

OBJECTIVES@#To analyze the chromatic properties and translucency of porcelain veneers made from different ceramic materials against the background of tetracycline-stained teeth.@*METHODS@#Porcelain specimens (A1, A3, B2, B4) measuring 0.50 mm in thickness were prepared by heat-press casting and layering. The L*, a*, and b* values of the specimens against simulated tetracycline tooth and black-and-white backgrounds were measured by a spectrophotometer, and color differences ΔE@*RESULTS@#The ΔE@*CONCLUSIONS@#When changing the color of tetracycline-stained teeth, 0.50 mm-thick IPS d.SIGN feldspathic veneers with an opaque layer provide better chromatic properties than IPS e.max Press LT glass ceramic veneers. However, the translucency of feldspathic veneers is generally poorer than that of glass ceramic veneers.

Interdisciplinary planning as a landmark for treatment: Case report with a 2-years follow-up

Abstract Case report: young adult woman with esthetic complaints regarding her smile and frontal teeth aspect. At first glance, the problem seemed to be only the shape of the lateral upper incisors and a small diastema between the central incisors. The diagnosis shared between the orthodontist and the prosthetist led us to consider some other important aspects, such as the deep bite, the teeth inclination and the lips support. All these findings led us to consider that the right way to improve the esthetics of the patient's smile was to plan an orthodontic treatment. This would serve not only for the distribution of the spaces, but mostly it would improve all other problems, before the restoration of the upper lateral teeth with two ceramic veneers. Results: the treatment plan achieved the right distribution of spaces for upper lateral incisors, significant correction of the incisors inclination with important reduction of overbite and better lip support, upper laterals restorations with ceramic feldspathic veneers, obtaining a good integration with natural teeth satisfying patient complaint. Conclusion: in cases which involve interdisciplinary approach, the fundamental step comes from the beginning, when only an initial diagnosis shared among the team of specialists can define the patient problems from different points of view. In this way, we can better understand the competency fields and plan the right treatment and time sequence.

Resumo Relato de caso: paciente adulta jovem, sexo feminino, buscou tratamento devido à queixa com a estética do sorriso e o aspecto dos dentes anteriores. À primeira vista, o problema parecia ser apenas o formato dos incisivos laterais superiores e um pequeno diastema entre os incisivos centrais. O diagnóstico conjunto do ortodontista e do protesista fez com que considerássemos outros aspectos importantes, tais como mordida profunda, inclinação dentária e suporte labial. A partir de todas essas constatações, consideramos que a maneira mais adequada de melhorar a estética do sorriso seria planejar o tratamento ortodôntico. Assim, o tratamento serviria não apenas para melhor distribuição dos espaços, mas também melhoraria todos os outros problemas antes da restauração dos dentes laterais superiores ser realizada com duas facetas de cerâmica. Resultados: o tratamento planejado levou à correta distribuição dos espaços nos incisivos laterais superiores, com correção significativa da inclinação dos incisivos, importante redução da sobremordida e um melhor suporte labial, com restauração dos laterais superiores usando facetas de cerâmica feldspática, obtendo-se uma integração ideal com os dentes naturais, resolvendo as reclamações da paciente. Conclusão: em casos envolvendo abordagem multidisciplinar, as etapas iniciais são fundamentais, e apenas um diagnóstico inicial discutido entre a equipe de especialistas pode determinar os problemas do paciente sob diferentes perspectivas. Dessa forma, podemos compreender melhor os campos de competência e planejar a sequência e o tempo de tratamento mais adequados.

Influence of Resin Cements on Color Stability of Different Ceramic Systems

Abstract The purpose of this study was to evaluate color stability of two dental ceramics cemented with two resin cements, assessing the color difference (ΔE00) by the measurement of L*, a*, b*, c* and h* of transmittance. The combination of two ceramic system (feldspathic and lithium disilicate) and two resin cements - color A3 (RelyX ARC and Variolink II) resulted in 4 groups (n=5). Ten disks-shaped specimens were fabricated for each ceramic system (10x1.5 mm), etched with hydrofluoric acid (10%) and silanized prior to cementation. The color analysis was performed 24 h after cementation of the samples and after 6 months of storage in relative humidity by means of spectrophotometry. The ΔE00 values were analyzed statistically by two-way ANOVA followed by the Tukey test (p<0.05). One-way ANOVA were calculated for the means of individual color coordinates (L*, a*, b*, c* and h*). Two-way ANOVA showed that only the ceramic factor was significant (p=0.003), but there was no difference for the cement factor (p=0.275) nor for the ceramic/cement interaction (p=0.161). The feldspathic ceramic showed the highest values of ΔE00. Variations in L*, a*, b*, c* and h* were more significant for feldspathic ceramic. In conclusion, storage alters similarly the optical properties of the resin cements and feldspathic porcelain was more susceptible to cement color change after aging.

Resumo O objetivo deste estudo foi avaliar a estabilidade da cor de dois sistemas cerâmicos em função de dois cimentos resinosos, avaliando a diferença de cor (ΔE00) pela mensuração de L*, a*, b*, c* e h* de transmitância. Formou-se 4 grupos (n=5) de acordo com as duas cerâmicas (reforçada com dissilicato de lítio e feldspática) e dois cimentos resinosos - cor A3 (RelyX ARC e Variolink II). Dez discos foram confeccionados para cada sistema cerâmico (10 x 1,5 mm), tratados com ácido fluorídrico (10%) e silanizados antes da cimentação. A análise de cor foi feita 24 h após a cimentação das amostras e após 6 meses de armazenamento em umidade relativa por meio de espectrofotometria. ANOVA a dois fatores foi utilizada para análise dos dados de ΔE00 seguido pelo teste de Tukey (p<0,05). ANOVA a um fator foi realizada para avaliação das coordenadas individuais de cor (L*, a*, b*, c* e h*). Apenas o fator cerâmica foi significativo (p=0,003),mas não houve diferença para o fator imento (p=0,275) nem para a interação entre cerâmica e cimento (p=0,161). A cerâmica feldspática apresentou os maiores valores de ΔE00. Variações de L*, a*, b*, c* e h* foram mais significativas para cerâmica feldspática. Concluiu-se que o armazenamento alterou as propriedades ópticas dos cimentos resinosos de forma semelhante e a porcelana feldspática foi mais susceptível à mudança de cor do cimento após o envelhecimento.

Micromorfología superficial de 2 cerámicas grabables tratadas con diferentes ácidos / Superficial micromorphology of 2 etchable ceramics treated with different acids

Para lograr una unión fuerte entre las restauraciones de cerámica sin metal y las resinas de cementación se indican acondicionamientos de superficie previos a la cementación. Nuestro objetivo es describir y comparar al MEB las superficies de cerámicas feldespáticas y reforzadas con disilicato de litio antes y después de ser tratadas con 2 procedimientos ácidos. Se utilizaron 8 bloques de cerámica feldespática (A) y 8 de cerámica reforzada con disilicato de litio (B). Se subdividieron en 2 grupos de 4 bloques (A1 y A2) y (B1 y B2). Los grupos A1 y B1 fueron tratados con ácido fluorhídrico 9% (HF) y los grupos A2 y B2 con ácido fluorhídrico, seguido de ácido fosfórico al 35%. Posteriormente, se observaron al MEB (1.000 ×) y se procesaron las imágenes con el programa Matlab R2012a, que mide el contraste. Los estadísticos utilizados fueron el test ANOVA y el test «t¼ no pareado Resultados El ácido fluorhídrico 9% crea irregularidades en ambos tipos de cerámicas. Al aplicar HF, seguido de ácido fosfórico sobre la cerámica feldespática no se aprecian diferencias en el contraste, con respecto a utilizar solo HF. Al usar ambos ácidos, en la cerámica reforzada con disilicato de litio se aprecian menos irregularidades respecto a las tratadas con un solo ácido. Conclusiones El ácido fluorhídrico 9% crea microrretenciones en ambas cerámicas. El HF al 9%, seguido del ácido fosfórico 35% parece modificar los valores de contraste de la cerámica colada, en cambio en las feldespáticas no hay diferencias significativas con ambos tratamientos.

Surface conditioning prior to cementing is indicated to achieve a strong bond between metal-free ceramic restorations and resin cements. The aim of this study is to describe and compare the scanning electron microscopy (SEM) images of the surfaces of Feldspathic ceramic and Lithium disilicate glass ceramic before and after being treated with two acid procedures. For this, 8 blocks of Feldspathic ceramic (A) and 8 of Ceramic lithium disilicate (B) were used. They were subdivided into two groups of 4 blocks (A1 and A2) and (B1 and B2). Groups A1 and B1 were treated with 9% Hydrofluoric Acid (HF) and the A2 and B2 groups, with 9% Hydrofluoric Acid followed by 35% Phosphoric Acid. Subsequently, they were observed using SEM (1,000 ×) and the images processed with the program Matlab R2012a, which measures the contrast. The statistics used were ANOVA test and the unpaired t test. Results 9% Hydrofluoric Acid creates irregularities in both types of ceramics. When applying HF followed by Phosphoric Acid on Feldspathic ceramics, no differences in contrast were found, compared to using only HF. With ceramic lithium disilicate using both acids, there are fewer irregularities with respect to those treated with a single acid. Conclusion 9% Hydrofluoric Acid creates micro-retentions in both ceramics. 9% HF followed by 35% Phosphoric Acid appears to significantly modify the Lithium disilicate glass ceramic contrast values. On the other hand, the Feldspathic ceramic showed no significant differences with both treatments.

Importância do enceramento diagnóstico na reabilitação estética e funcional / The diagnostic wax-up as an important tool in the aesthetic and functional rehabilitation

Restaurações à base de resina composta direta têm mostrado boas taxas de longevidade, no entanto, apresentam comprometimento estético ao longo do tempo. Para suprir essa carência, as restaurações cerâmicas têm se tornado uma ótima opção de tratamento para dentes anteriores, sendo a cerâmica feldspática a que apresenta melhores propriedades estéticas e capacidade de reprodução de detalhes. Assim, este artigo procurou descrever a confecção de quatro laminados cerâmicos, à base de cerâmica feldspática, para restauração de incisivos superiores, inicialmente restaurados com restaurações insatisfatórias em resina composta. Após a conclusão da reabilitação, foi possível concluir que o tratamento restabeleceu satisfatoriamente a estética e a função da paciente.

Resin composite restorations show good survival rates; however, they present esthetic problems after longer clinical periods. For this, ceramic restorations are a good alternative and feldspathic ceramics present the best esthetic properties. This article describes the fabrication of four laminate veneers with feldspathic ceramics to restore the maxillary incisors with unsatisfactory composite restorations. Good levels of esthetic and function were achieved at case conclusion.

Effect of different surface treatments on microtensile bond strength of two resin cements to aged simulated composite core materials.

Objective: Roughening of the aged composite resin core (CRC) surface seems essential for durable adhesion. The aim of this study was to investigate the influence of various surface treatments and different resin cements on microtensile bond strength (μTBS) between two aged core build‑up composites (CBCs) and feldspathic ceramic. Materials and Methods: A total of 16 composite blocks made of two CBCs, Core.it and Build‑it were randomly assigned to four surface treatment groups after water storage and thermocycling (2 weeks and 500 cycles). Experimental groups included surface roughening with air abrasion (AA), hydrofluoric acid, pumice, and laser and then were bonded to computer‑aided design/computer‑aided manufacturing feldspathic ceramic blocks using two resin cements, Panavia F2 (PF), and Duo‑link (DL). The μTBS was tested, and the fracture mode was assessed. The data were analyzed with multiple analysis of variance to estimate the contribution of different surface treatments, resin cements, and two aged CRCs on μTBS. Statistical significance level was set at α < 0.05. Results: Surface treatment and cement type significantly affected bond strength (P < 0.001) but the type of CRC did not (P = 0.468). Between roughening methods, the highest and the lowest values of μTBS were sequentially obtained in AA and Er.YAG laser groups. The highest bond strength was in AA group cemented with PF (31.83 MPa). The most common failure mode was cohesive fracture in the cement. Conclusion: Different surface treatments had different effects on μTBS of aged CRCs to feldspathic ceramics. PF was significantly better than DL.