ABSTRACT
AIM: This study aimed to evaluate the enamel microhardness, surface roughness, and chemical composition after microabrasion technique, followed by polishing and different immersion times in artificial saliva. Materials and methods: Ninety enamel blocks (25mm2) from bovine incisors were divided into two groups (G1 and G2), and then subdivided in five subgroups (n = 9) according to their microabrasion treatment and polishing with a diamond paste: 35% phosphoric acid and pumice (H3PO4+Pum) and polishing; just H3PO4+Pum; 6.6% hydrochloric acid and silica (HCl+Sil) and polishing; just HCl+Sil; and control (no treatment). For G1, roughness and microhardness analyses were performed before (L1) and after (L2) microabrasion. After 15 (L3) and 30 (L4) days of immersion in artificial saliva, microhardness analysis was also performed. After (L4) analysis, the specimens were subjected to SEM analysis. G2 was used for the chemical analysis using energy dispersion testing (EDS). The data was subjected to statistical analysis (α = 5%). For roughness, L2 presented higher values than L1, except for the polished groups. For microhardness, L2 presented higher values than L1, except for unpolished groups. The L3 and L4 did not differ and were higher than L1. RESULTS: No changes were observed in the phosphorus concentrations of the microabrasioned enamel. However, the specimens treated with HCl+Sil were observed as having decreased calcium and increased chlorine and silica on the EDS test. Conclusion: Microabrasion followed by polishing and immersion in artificial saliva for 15 days is enough to increase the microhardness of microabrasioned enamel surfaces, although the microabrasion procedure can alter the mineral content of the enamel.
Subject(s)
Hydrochloric Acid/chemistry , Dental Enamel/physiology , Enamel Microabrasion , Incisor , ThymolABSTRACT
O desgaste dos dentes anteriores pode acarretar desarranjos funcionais, assim como desarmonia estética. Devido a suas ótimas propriedades ópticas e biomecânicas, as cerâmicas dentais têm sido cada vez mais utilizadas na resolução de problemas relacionados à estética do sorriso. As cerâmicas reforçadas por dissilicato de lítio são opções viáveis para esse tipo de reabilitação. Nesse sentido, todos os passos para realização da restauração indireta cerâmica são críticos e de extrema importância. O objetivo deste artigo é apresentar, por meio do relato de um caso clínico, a confecção de restaurações de dentes ântero-superiores com severo desgaste, com coroas totais em cerâmica reforçada por dissilicato de lítio. Para a realização de casos com previsibilidade e sucesso, as diferentes etapas de confecção são detalhadas e minuciosamente discutidas, e demonstram-se os pontos chave desse procedimento...
Wear of anterior teeth can cause functional disorders, and esthetic disharmony. Due to their excellent optical and biomechanical properties, dental ceramics are increasingly used to solve esthetic problems. Reinforced ceramics, e.g. those composed by lithium disilicate, are feasible options for this type of rehabilitation. Therefore, every step involving the fabrication of indirect ceramic restorations is critical. This article presented a case report of the restoration of maxillary anterior teeth with severe wear, using full crowns fabricated with lithium disilicate reinforced ceramics. The steps are described in detail and thoroughly discussed, demonstrating key concepts to achieve predictable, successful results...
Subject(s)
Humans , Female , Cementation , Ceramics , Crowns , Esthetics, Dental , Tooth WearABSTRACT
The aim of this in vitro study was to evaluate the effect of different mouthwashes on superficial roughness and Knoop hardness of two resin composites. Eighty specimens (6 mm Ø and 2 mm height) were prepared and divided into eight experimental groups (n = 10) according to the resin composites (4 Seasons and Esthet X), and storage solutions (G1 - Distilled water; G2 - Colgate Plax Overnight; G3 - Colgate Plax Alcohol Free; and G4 - Colgate Plax Whitening). The initial hardness and roughness readings (T1) were measured and then the specimens were stored in 2 mL of mouthwash for 12 h (T2) and 24 h (T3). The data were analyzed with repeat-measures two-way ANOVA and Tukey's test (α = 5 percent). Regardless of the type of solution and time of exposure, there was no statistical difference for roughness between the resins (p = 0.44). G4 and G8 presented higher roughness means than G1, G3, G5 and G7, after 12 and 24 hours of immersion. For Knoop microhardness analysis, there was a significant reduction for all groups after 12 hours and 24 hours. We conclude that the mouthwashes containing hydrogen peroxide and/or alcohol decrease the microhardness of the resins tested; however, the mouthwash containing hydrogen peroxide had a higher deleterious effect on roughness.
Subject(s)
Humans , Composite Resins/chemistry , Mouthwashes/pharmacology , Analysis of Variance , Hardness Tests , Hydrogen Peroxide/chemistry , Immersion , Materials Testing , Statistics, Nonparametric , Surface Properties/drug effects , Time FactorsABSTRACT
O protocolo restaurador direto com resina composta para dentes anteriores fraturados é um desafio na Odontologia Adesiva atual, já que existem vários compósitos à disposição no mercado, com características ópticas e mecânicas cada vez mais semelhantes às da estrutura dentária. Dessa forma, a técnica de estratificação em camadas de resina composta torna-se eficiente para uso na clínica odontológica. Nesse artigo, o caso clínico apresentado abordará a restauração estética de um incisivo medial fraturado, com o procedimento de estratificação de resina composta, trabalhando os conceitos de translucidez e opacidade para uma adequada reabilitação dentária de forma estética e funcional.