Magnus Larissa, Maltz Marisa, Bavaresco Caren, Bastos Lucelen F, Hashizume Lina N
Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Brazil.
J Oral Sci. 2013;55(2):133-7. doi: 10.2334/josnusd.55.133.
The aim of this study was to evaluate the concentrations of calcium (Ca), inorganic phosphate (Pi) and fluoride (F) in carious dentin and in different layers of sound dentin. The samples examined were 52 permanent teeth (26 sound and 26 carious), which were subjected to two experiments to assess the mineral content of: 1) two layers (internal and external) of sound dentin and 2) sound and carious dentin. Ca and Pi were analyzed using a colorimetric method with arsenazo III (C22H18As2N4O14S2) and molybdate reagents, and F was analyzed using a specific electrode. A non-parametric test, the Mann-Whitney test, was used to verify differences between groups. Sound dentin showed a higher concentration of fluoride in the internal layer than in the external layer (P = 0.03), but no inter-layer differences in Ca or Pi concentration were evident. Lower concentrations of Ca, Pi and F were observed in carious dentin than in sound dentin (P < 0.05). The results of this study suggest that the internal layer of sound dentin has a higher fluoride content than the external layer, and that carious dentin has lower concentrations of Ca, Pi and F than sound dentin.
本研究的目的是评估龋损牙本质和不同层次健康牙本质中钙（Ca）、无机磷酸盐（Pi）和氟（F）的浓度。所检测的样本为52颗恒牙（26颗健康牙和26颗龋损牙），这些牙齿接受了两项实验以评估以下部位的矿物质含量：1）健康牙本质的两层（内层和外层）；2）健康牙本质和龋损牙本质。采用偶氮胂III（C22H18As2N4O14S2）和钼酸盐试剂的比色法分析Ca和Pi，使用特定电极分析F。采用非参数检验，即曼-惠特尼检验来验证组间差异。健康牙本质内层的氟浓度高于外层（P = 0.03），但Ca或Pi浓度在层间无明显差异。龋损牙本质中的Ca、Pi和F浓度低于健康牙本质（P < 0.05）。本研究结果表明，健康牙本质的内层比外层含有更高的氟含量，且龋损牙本质中的Ca、Pi和F浓度低于健康牙本质。
