In the previous study, we reported that 95.6% of senior high school students who were diagnosed with dental caries understood that they had cavities. However, only 42.0% of the students understood the diagnosis of gingivitis. Thus, we concluded that senior high school students had less understanding of gingivitis compared to dental caries. On the other hand, among the students who were advised to visit dental office for treatment, only 44.3% and 55.9% received treatment for dental caries and gingivitis respectively. In order to enhance the understanding of gingivitis in senior high school students and increase the follow-up dental treatment, oral health education was performed on the site of the annual dental health examination. The subjects were the 1st grade students of one of the public senior high schools in Hiroshima City. They learned about gingivitis and dental calculus by being shown color photos immediately after the examination. Then they were asked to write down the results the dental health examination on their own health record cards. In addition, the written notice informing students about dental treatment was improved. In order to investigate a influence of oral health education, a questionnaire was performed 1 and 4 months later, and the results were compared with those of 1st grade students of the previous year. As a result, the ratio of students who understood the diagnosis of gingivitis increased from 50% to 72%, but despite this the ratio of students who visited a dental office did not change. Thus, we suggest that health education including both oral health and lifestyle, are necessary for senior high school students.
The physiological mechanism of periodontal destruction by smoking is not clear. Subgingival temperature (ST) was compared in maxillary anterior teeth between 46 smokers and 53 non-smokers in sites with similar probing depth. The effects on tooth number, the plaque index and gingival index scores on ST were not significant (p=0.6835, 0.6464 and 0.0730, respectively). Non-smokers showed higher ST in deeper pocket (p=0.0033), while no significant association was found in smokers (p=0.2807). ST at sites with probing depth of 3mm, 4mm and 5mm was significantly hihger (p=0.0048, 0.0129 and 0.0457, respectively) in smokers (35.2±0.7℃, 35.5±0.6℃ and 35.7±0.8℃, respectively) than in non-smokers (34.3±0.9℃, 34.6±1.1℃ and 34.9±1.1℃, respectively). No significant difference in ST was found between somkers (35.6±0.4℃) and non-smokers (35.8±1.1℃) in sites with probing depth of 6mm (p=0.2627). These results indicate that ST was higher in somkers than in non-smokers in shallow pocket, suggesting that increased ST may be involved in the development of smoking-related periodontal disease before and/or at earlier stage of destruction.
To establish the criteria of individual daily fluoride intake (DPI), fluoride analysis is necessary to ascertain the adequate intake (AI) of fluoride on a world-wide basis. Monitoring fluoride intake is useful in terms of fluoride application for the prevention of dental caries and oral diseases. The purpose of this study was to estimate DPI for food samples of commercially available infant formula and baby food. Fluoride was determined by hexamethyldisiloxane-microdiffusion method at 60℃ for 12 hr over. Fluoride concentrations of infant formula (ready-to-feed) with 0.1 ppm fluoride drinking water ranged from 0.14 to 0.22 μg/ml (mean 0.17 μg/ml, n=10), and fluoride contents of cereal, meat and fish, vegetable and juice showed mean value of 0.30 (n=11), 013 (n=20), 0.23 (n=11) and 0.10 μg/g (n=6), respectively. The estimated mean DFIs for infants 3-4, 5-6, and 7-8 months of age were 0.166, 0.202, and 0.266 mg/day. DFIs according to body weight ranged from 0.023 to 0.029 mg/kg in infants of 3-8 months of age, which were below the 0.05-0.07 mg/kg levels that are currently the criteria for the occurrence of enamel fluorosis. Based on these results we suggest that with the establishment of the AI of fluoride, regional guidelines for different fluoride concentrations in drinking water can be established.
The aim of this study was to investigate the effects of dental health promotion activities at the worksite by analyzing dental and medical expenses and the number of visits made for dental and medical treatment. Methods: The subject group was composed of 357 male workers who were provided with a preventive dental care program at their workplace. A follow-up study of the number of dental health promotion activities made between 1992 and 1997 also accounted for dental expenses, medical expenses, dental and medical treatment visits between 1992 to 1998. Results: 1) Compared to the group making 0-1 visits, the group that participating in the preventive program 2-3 times and 4-6 times reduced their dental expenses and numbers of visits for dental treatment. 2) Moreover, medical expenses excluding dental expenses and the number of visits for medical treatment were also reduced. 3) Similarly, total medical expenses including dental expenses and the total number of visits for medical and dental treatment were also reduced. 4) The implementation of a preventive program taking 20 minutes and consisting of dental examinations, counseling and calculus scaling proved effective. Conclusion: The results suggest that worksite promotional activities for dental health promotion activities effectively reduce dental and medical expenses and the number of visits required for dental and medical treatment. This underscores the relationship between the comprehensive health care approach including dental health promotion and medical expenses.
The purpose of the present study was to examine whether the Aesthetic Component (AC) scale, a method for the aesthetic evaluation of the Index of Orthodontic Treatment Need (IOTN), could be used successfully for self evaluating the need of orthodontic treatment in Japanese patients. The subjects were 173 of 177 students, with a mean age of 21.3 years, who had received no previous orthodontic treatment. The AC scale was used to self-evaluate malocclusions. For epidemiological evaluations performed by dentists, AC, the Dental Health Component, which provides functional evaluations of IOTN and Dental Aesthetic Index were used. The following results were obtained: 1. For epidemiological evaluation, 19.1% of the subjects were determined to need orthodontic treatment by AC, 45.1% by DHC, and 41.6% by DAI, while 32.9% were rated necessary by both DHC and DAI. 2. Self-evaluation using the AC scale found that 2.3% needed treatment. On the basis of the above findings, it was considered that further evaluation of orthodontic treatment is necessary, because epidemiological evaluations using AC, DHC and DAI were markedly different from self-evaluation using AC.
It is well known that the inadequate intake of the essential trace element zinc (Zn) leads to a number of clinical symptoms, including growth retardation, decreased immunity, and gustatory abnormalities. However, many aspects of the expression mechanisms and Zn metabolism during Zn deficiency are still unknown. Therefore, the aim of this study was to investigate the effects of Zn deficiency on oral mucosa tissue, in particular periodontal tissue, by dividing twelve 4 week old male Wistar rats into 2 groups, a control group and a Zn deficient group, and rearing them for 3 weeks on special powder feed. The results showed that the increase in body weight in the Zn deficient group was more gradual than that in the control group; depilation in the abdominal and neck regions beginning about 2 weeks after starting the experiment, together with low serum Zn and serum ALP activity levels. Scanning electron microscopy revealed the accumulation of foreign bodies in the Zn deficient group and irregular morphology. Although light microscopy did not reveal any changes in periodontal tissues in the Zn deficient group in the present study, keratinization of the mucosal cortex in the palatal region and complex keratinization extending from the gingivobuccal fold region to the buccal mucosa were observed.