Questionnaire survey of dental health behavior was conducted among mothers of 286 3-year-old children receiving a health check-up in April 1998. Responses to each question were classified into 5 ranks (1 : I strong think so, 2 : I think so, 3 : neutral, 4 : I am doubtful, 5 : I don't think so at all) and the data were analyzed statistically. First, the relations between each pair of questions was analyzed using Peason's correlation coefficient. And it was shown that some consciousness regarding the seriousness of dental caries, sense of self value in preventive behavior and parents role, were related to "interest" being a large acting force for the health behavior. For example, parents who were strongly conscious of these issues believed that maintaining the dental health of their children is the role of parents, tended to be very interested in the oral health of their child. Then it was analyzed whether this consciousness differed by family environment using t-test. Mothers who often talk about child care with their husbands have a high sense of self value in teaching preventive behavior. Compared with mothers who have gotten some knowledge of dental health from T. V. or magazines, mothers who have were instructed by dentists tended to be more conscious about the seriousness of deciduous tooth caries, and valued going to the dental clinic as a preventive behavior. It was shown that social support, the father's participation in child care, and knowledge of dental health raised their sense of self value in teaching preventive behavior and sense of the parents' role and that mothers with positive consciousness of these issues tended to perform good dental health behavior. Mothers perform good health behavior for their children is related not only to positive consciousness but also to the group norm of the reference group. As a result, dental health guidance was given at all dental check ups for children, effectively promoting consciousness about dental health, so that mothers and children could achieve better dental health behavior. This study was supported by a Grant-in-Aid for scientific research from the Japanese Ministry of Education, Project No. 08672589.

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Tongue coating is closely related to oral malodor. In this study, the relationship between tongue coating and oral malodor was evaluated as to whether tongue coating score was effective as a screening test for oral malodor. For the initial research, the subjects were 10 university students. Oral malodor was measured using a portable sulphide monitor and the UBC-style organoleptic rating technique. To evaluate the tongue coating, the tongue coating score and tongue coating wet weight were examined. The results indicated that there were positive correlations between mouth odor intensity (organoleptic scores, VSC values) and tongue coating wet weights, between tongue coating wet weights and tongue coating scores, and between tongue coating scores and mouth odor intensity. In an epidemiological study, the subjects were 108 senior high school students. The tongue coating score was examined and oral malodor was measured using a portable sulphide monitor. There was a positive correlation between VSC values and tongue coating scores, and subjects with a tongue coating score of 2 or 3 had high VSC values. Furthermore, the measurement results were analyzed by adapting them to the assessment method of the screening test. Oral malodor was classified as negative when the tongue coating score was 0 or 1 and as positive when the score was 2 or 3. In the portable sulphide monitor measurement, it was decided that a VSC value over 150 ppb was unpleasant. The sensitivity was 55% and the specificity was 71% in the measurement result between 11:00 and 13:00 when oral activity has little influence on VSC value. Both studies indicated that there was a close correlation between oral malodor intensity and tongue coating score. It was also suggested that the tongue coating score can be an indicator of whether a person has unpleasant mouth odor or not.

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The objective of this report was to describe the dental service utilization pattern of periodontal treatment and the periodontal expenditure pattern in private dental clinics in Japan. Dental care records registered in the national medical expenditure survey of 1980, 1983, 1985, 1990 and 1994 were used. The results were as follows ; 1. The percentage of dental care records of periodontal treatments had gradually increased since 1985. In 1994, 52% of the records were involved in periodontal treatments. However, the proportion of periodontal disease expenditure on total dental care was 17%. 2. Dental care records of periodontal disease treatments were classified into 5 groups : oral hygiene instruction, periodontal examination, non-surgical treatments, antiphlogistic treatments and surgical treatments. The percentage of dental care records registering oral hygiene instruction increased during 1980-1994. 3 . The percent distributions of the 5 periodontal treatments listed above were almost identical among all age groups between 20 and 69. The mean periodontal expenditure per patient in the 40-49 age group was highest among all the age groups.

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A fluoride mouthrinse is necessary to promote oral health planning for the prevention of enamel and root surface caries throughout life. The aim of this study is to estimate fluoride (F) uptake to human enamel and root surfaces with two F mouthrinses available (FMOB ; ORABLISS®, FMMR ; MIRANOL® ) in vitro. To determine F uptake to enamel and root surfaces with various F concentrations of mouthrinse, enamel and root surface blocks were immersed with starring in 250 ppm and 450 ppm solutions of F mouthrinse at 37℃ for 24 hr. After fixation with 50 mM primary calcium phosphate (saturated, pH 7.4) and washing with distilled water, surface sampling was performed with 0.5 M HCl0_4 at 5, 10, 15, 30, 60 and 120 sec. The results were as follows ; 1) F concentration in enamel and root surfaces in the two F mouthrinse groups (250 ppm, 450 ppm, pH 5.5) showed a significantly higher value than that of each control group (p < 0.05). 2 ) F concentration profile in enamel with each 450 ppmF solution was approximately twice as high as that of the 250 ppmF solution in the first layer (2 μm). F uptake was almost similar in the 2 nd layer. 3 ) F concentration to the root surface with F mouthrinse was significantly twice as high as that of enamel at 20 μm depth (p < 0.05). These results suggest that fluoride mouthrinses are promising preventive measures for root surface caries in the adult population in terms of a clearly higher fluoride uptake in in vitro assessment.

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The inclusion of patient-driven measures, such as oral health-related quality of life (QOL), is critical. A 49-item Oral Health Impact Profile (OHIP-49) is recognized worldwide to be the most sophisticated and comprehensive instrument for measuring the outcome of oral disease. Objects : The purpose of this study was to evaluate the reliability of the Japanese edition of OHIP-49. Methods : Data were collected by means of a self-administered questionnaire to a sample of 7,277 civil employees aged 19-78 years. We examined three point : 1) descriptive analysis 2) reproducibility 3) internal consistency. The reproducibility of the profile was evaluated in 30 persons aged 26-66 years. Results : Questions were left blank or unknown by 2% or less. The к-value of each question was nearly stable. The correlation between test and retest ranged from 0.61 to 0.81 in seven domains demonstrating good reproducibility. Values of Cronbach's α for seven of the domains ranged from 0.83 to 0.94, indicating the good internal consistency of those domains. Conclusion : The findings suggested that the Japanese edition of OHIP-49 has good reliability. It seemed reasonable to assess the dental health-related QOL with the Japanese edition of OHIP-49, although further study using other subjects would be required.

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We reported previously that dentinal fluid flow caused by intrapulpal pressure has considerable effects on the de- and remeralization of root surfaces. The same mechanism may work in the dentin wall of cavities. This study was conducted to examine the effects of glass ionomer cement (GIC ; Fuji ionomer Type II, GC) as a typical fluoride-releasing material on remineralization of the demineralized cavity bottom in the presence of dentinal fluid flow in vitro. A cylindrical cavity (3 mm in diameter and 2 mm in depth) was prepared in the buccal surface of the crown of a bovine incisor. The cavity was filled with GIC or amalgam (control) according to the manufactures' instructions. The pulpal cavity of incisors was filled with a pulpal fluid based mineral solution (0.65mM CaCl₂, 0.94mM KH₂PO₄, 20mM Hepes buffer, pH 7) and pressured at zero or +20 mmHg for 7 d. After the treatments, the mineral distributions were assessed microradiographically with the aid of computer assisted videodensitometry (CAV). The 1_d and ΔZ values of the GIC group were significantly lower compared with the amalgam group under + 0 mmHg pressure, indicating enhanced remineralization. In contrast, it was found under +20 mmHg pressure that the amalgam group and GIC group had no significant differences in 1_d and ΔZ values. Thus, it was revealed that the mineral recovery of cavity bottom by GIC was restricted under +20 mmHg pressure. In conclusion, it is suggested that the effects of fluoride-releasing material on remineralization of cavity bottom could be strongly influenced by dentinal fluid flow.

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From the viewpoint that a biofilm behaves as a biological ecosystem to protect human tissues in general, this study investigated de- and remineralization of enamel with or without the presence of a plaque biofilm formed in vitro using a biological caries model. Experimental microcosm plaque was cultured on bovine enamel blocks in an 'artificial mouth' by supplying a BHI (Difco)-human saliva mixture and 15% sucrose at the rate of 0.1 ml/min on bovine enamel slabs at 37℃ for 5 d resulting in the formation of a caries-like lesion with a lesion depth value 1_d (μm) of 120±9μm (mean±SD). Remineralization tests were done by supplying a mineral solution (1.5 mM CaCl₂, 0.9mMKH₂PO₄, 20 mM Hepes, 2 ppmF as NaF) only or a BHI plus mineral solution mixture on the enamel slabs with or without the experimental plaque biofilm in vitro (n = 6 per treatment). All the samples were microradiographed to measure the 1_d and mineral loss value ΔZ (vol%・μm). After 7-d incubation, the samples treated with BHI-mineral solution mixture under the biofilm showed a significantly lower 1_d value of 51±12 μm and ΔZ value of 1,572±206 vol%・μm (p<0.05) compared with the samples exposed to a mineral solution only under biofilm (1_d = 87±8μm, ΔZ = 1,932±221 vol%・μm) and without biofilm (1_d = 110±14μm, ΔZ = 4,225±1,295 vol%・μm). Thus, plaque biofilm may work as a biological reservoir of mineral and fluoride ions, and thereby contribute to tooth protection by regulating the de- and remineralization process. In conclusion, it is suggested that the biological caries model is applicable and useful as an oral simulator to form a mixed salivary bacteria-based plaque biofilm, and early caries lesions in enamel might be remineralized under biofilm.

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The objective of this study was to investigate the use of an Electrical Caries Monitor (ECM) for detecting the progression of demineralization in subsurface enamel lesions in vitro. Sound bovine enamel blocks (4×4×3 mm) indicating ECM values of 99.99 MΩ were selected for the experiment. Twenty-four specimens in 4 groups were demineralized in a 0.1 M lactic acid gel containing 6 wt% carboxymethylcellulose (pH 5.0) for 1, 2, 3, 4 w intervals, respectively. All the specimens were assessed by ECM and transversal microradiography (TMR) after the demineralization procedure. The results showed that ECM values greatly decreased with the time of demineralization, and the ECM was sensitive enough to detect enamel lesions extending up to about 100 μm in depth. Moreover, ECM values were correlated significantly with the TMR parameter values, namely lesion depth (1_d, r=-0.79) and mineral loss (ΔZ, r=-0.88) at p<0.001. It is suggested that ECM can be used as a device to detect enamel demineralization in vitro. This result may encourage the application of ECM in detecting early carious lesions in vivo and contribute to clinical decision-making.

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Phosphoryl oligosaccharides (POs) were prepared from potato starch hydrolysates. The effect of POs on acid fermentation by mutans streptococci, Streptococcus mutans MT 8148 and Streptococcus sobrinus 6715, was evaluated in vitro. POs were not fermented by mutans streptococci and therefore did not cause a decrease in pH in the culture. It was also observed that POs inhibited the pH drop ascribed to the fermentation of sucrose in a dose-dependent manner. The production of lactic acid by mutans streptococci was not suppressed by POs during sucrose fermentation, suggesting that POs inhibited the pH drop by their buffering action. Hence, POs might be a beneficial food substance for dental health.

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