Effects of Titratable Acidity and Organic Acids on Enamel Erosion In Vitro

Effects of titratable acidity and organic acids on enamel erosion in vitro Kim Eun-Jeong, BSDH, RDH (Directed by Associate Prof. Jin Bo-Hyoung, DDS, MSD, PhD) Department of Preventive and Social Dentistry, The Graduate School, Seoul National University The aim of the present study was to determine the erosive potential difference among four naturally acidic fruit nectars (mandarin, orange, lemon, grapefruit) within the same range of titratable acidity and the influence of the components of organic acids on dental erosion. Diluted fruit nectars (mandarin 1:1.1, orange 1:1.7, lemon 1:15, grapefruit 1:20) with the same range of titratable acidity (7.9 mL) were used. Specimens were randomly allocated to each group and were placed in a conical tube with 50 mL of test solutions for 1 h. Before and after procedure, enamel erosion was measured by micro-hardness test, CLSM and SEM (p > 0.05). The separation of acids was carried out using a high performance liquid chromatography to analysis composition of each test solution. Enamel erosion occurred with all test groups and showed similar decrease in VHN (no statistically differences were founded in the enamel surface hardness after erosion). The surface roughness changes were similar in the diluted orange, diluted lemon, and diluted grapefruit juices. The changes in the diluted mandarin nectar were different from those in the other experimental groups. The specimens of each group showed different patterns of enamel surface by SEM images. The citric and malic acids were the major organic acids in all test fruits. The lemon and orange groups had the highest malic acid concentrations; the mandarin group had the lowest malic acid concentration. The titratable acidity, citric and malic acids of fruits could be crucial factors in enamel erosion; therefore, fruit-based drinks should be regarded as potentially erosive.