Surface microhardness evaluation of enamel and dentin in bovine and human teeth (permanent and deciduous)

• Autor(a) principal: Donassollo, Tiago Aurélio
• Data de Publicação: 2007
• Outros Autores: Romano, Ana Regina, Demarco, Flávio Fernando, Della-Bona, Álvaro
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista odonto ciência (Online)
• Texto Completo: https://revistaseletronicas.pucrs.br/ojs/index.php/fo/article/view/1118
• topic: microhardness; human teeth; bovine teeth

The objective of this study was to evaluate the surface microhardness of enamel (E) and dentin (D) from human deciduous molar teeth (Group d), human permanent molar teeth (Group p) and bovine incisor teeth (Group b). Four specimens were selected for each group and stored in saline solution until testing. The specimens were embedded into a resin matrix and polished to 600 grit SiC paper creating a flat enamel surface. The Knoop hardness test was performed in a microhardness device, using a 200 g load. Five measurements were made in each specimen. After that, specimens were polished to expose dentin (near to dentinenamel junction), and other five microhardness measurements were performed per specimen. The values were calculated and statistically analyzed (ANOVA and Tukey tests). Mean hardness values (kg/mm2) and standard deviations were as follows: Ed 338 ± 30.1; Ep 341 ± 32.8; Eb 326 ± 25.5; Dd 104 ± 9.7; Dp 93.3 ± 8.7; Db 91.2 ± 7.3. The microhardness in enamel (E) was statistically higher than in dentin (D) for the three type of teeth studied (p < 0.001). Considering the type of substrate, there were no statistical differences, meaning that the mean hardness values for either enamel or dentin were not different for the human deciduous teeth, human permanent and bovine teeth. UNITERMS: microhardness; human teeth; bovine teeth.