Abstract
In this study, we aimed to develop an effective method for remineralization (REM) of enamel with incipient dental caries. The effects of phosphoryl oligosaccharide calcium (POs-Ca) with various fluorides on REM was evaluated by quantitative light-induced fluorescence (QLF) and transverse microradiography (TMR). Bovine enamel surfaces (1×5 mm) were covered with clear nail varnish and then demineralized using a two-layer method with an 8% carboxymethyl cellulose gel and 0.1 M lactate buffer (pH 4.5) at 37℃for 2 weeks, then immersed in PBS for 1 day. After removing the varnish with acetone, fluorescence loss［ΔF(%)］，ΔQ(％・mm2), and white spot demineralized area size［WS area (mm2)］of the enamel samples were determined by QLF. As a test of experimental surfaces, the enamel surfaces were again covered with the same varnish, then remineralized at 37℃under various conditions in the presence of POs-Ca (0.48%), 1.2 ppmF of green tea fluorine, acidulated phosphate fluoride (APF), or NaF. REM was determined by QLF, then mineral loss (ΔZ) and lesion depth (ld) of the remineralized samples were determined by TMR. After a 1-week REM period, ΔΔF, ΔΔQ, and ΔWS area were determined by QLF. The REM of the POs-Ca group (CP group), CP＋green tea F group (CPF group), CP＋APF group (CPAPF group), and CP＋NaF group (CPNaF group) showed them to be significantly more effective than the control group (C group : Ca/P ratio＝0.4). The REM rate using ΔZ and ld of each REM group was determined by TMR. The REM rates of the control group, CPF group, CPAPF group, and CPNaF group were 12.22±5.37%, 58.10±10.87%, 56.54±8.46% and 48.60±12.75%, respectively. When effects of various fluorides on REM were compared,green tea F tended to promote REM more effectively than the others. Furthermore, promotion of REM by POs-Ca was significantly reinforced as compared to the control by addition of fluorides.
