Although accumulated epidemiological and biological evidence has revealed that periodontal disease is associated with atherosclerosis, the association of dental caries with the disease is not well understood. The objective of this study was to review current biological and epidemiological evidence of adult dental caries and atherosclerosis, in order to assess risk factors. The association between dental caries and atherosclerotic lesions has not been clearly demonstrated. A few epidemiological studies have shown that adults with a higher level of alcohol consumption or frequent sugar intake had more decayed teeth compared with those without such habits. Based on epidemiological findings published after 1950 as well as biological findings, a relationship between active smoking and adult dental caries is thought to exist. In addition, metabolic syndrome is an accumulation of conditions that also increase the risk of atherosclerosis, such as obesity, hypertension, dyslipidemia, and hyperglycemia, and a study of middle-aged Japanese men reported that the number of decayed teeth was significantly correlated with increased odds of metabolic syndrome after adjustments for health behaviors as potential confounders. That relationship was observed even in men without periodontal pocket formation and those without missing teeth, while it was also revealed that the presence of decayed teeth was significantly correlated with each of those atherosclerotic risk factors. Although the underlying mechanisms of the relationship of decayed teeth with atherosclerosis remain unclear, recent reports have noted the involvement of Streptococcus mutans, a cariogenic dental pathogen, in the pathogenesis of atherosclerosis. The high prevalence of metabolic syndrome is a global public health problem, and 50% of men and 20% of women in Japan have that or pre-metabolic syndrome. Oral health professionals are encouraged to provide education through health services regarding the adverse effects of decayed teeth, as well as the importance of dental caries treatment for the prevention and control of metabolic syndrome and atherosclerosis. Nevertheless, because of insufficient evidence, further research is needed to investigate whether dental caries is a true risk factor for atherosclerosis, including molecular biological experiments and longitudinal epidemiological studies.

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 Many microorganisms have been found to colonize the dorsum of the tongue, and they cause oral halitosis and aspiration pneumonia. Since the components of such biofilm (tongue coating) mainly consist of protein debris, bacteria, desquamated epithelial cells, and leukocytes, the purpose of this study was to evaluate the effects of a protease (papain)-containing gel as an adjuvant for mechanical tongue cleaning to remove tongue coatings. The subjects were 20 healthy adult volunteers (13 males and 7 females) aged from 23 to 53 years. We conducted a double-blind randomized crossover trial. Subjects were administrered gels without (placebo) or with papain. On the experimental day, subjects had 2.5 g of the assigned test or a placebo gel applied to their tongue dorsum and it was left for 1 min. Then, the same dentist cleaned their tongues using a tongue brush with a load range from 100 to 150 g. Subjects were instructed to gargle with 20 mL of water for 10 sec after tongue cleaning. We carried out an assessment of the amounts of tongue coating before and after tongue cleaning. Pictures of their tongue dorsum were taken to evaluate area ratios of tongue coating per whole area of the dorsum based on image analysis. Each day was followed by a 14-day washout interval. For analysis of dorsum images, three trained dentists who were blinded to the subjects traced outlines of both the dorsum and tongue coating and evaluated the tongue coating thickness they recognized visually using the software Image J. The Wilcoxon signed-rank test was employed to compare the tongue coating status between the two groups. When compared with the results from the control group, the ratio of tongue coating per whole area of the dorsum was significantly decreased (p<0.05), and the remaining ratio of the tongue coating was significantly lower (p<0.05) in the test group after tongue cleaning. The tongue coating thicknesses were significantly decreased (p<0.05) in both groups after tongue cleaning. These results suggest that the gel containing papain is effective for removing tongue coatings as an adjuvant for mechanical cleaning.

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 This study examined the effectiveness of a dietary education support program (DESP) aimed at improving masticatory ability and handgrip strength.
 In this study, subjects were students from a public high school who consented to participation. Subjects were randomly divided into a group receiving DESP and a control group not receiving DESP. Both groups received health guidance from a dental hygienist prior to the initiation of the trial. The subjects in DESP ate chewy donuts containing soymilk and soy pulp to which liquid konjak had been added (trade name: "Chewin' Donuts!" Kekkou Kamigotae-aru Donatsu^® manufactured by Shiraho Tanpaku Co., Ltd.). Subjects in this group were instructed to masticate consciously and ingest one donut per day for 7 consecutive days. The masticatory ability and handgrip strength of the left and right hands were measured in both groups at the beginning and end of the trial, and the mean values were calculated. The amount of sugar elution from chewing gum was measured to evaluate the direct masticatory ability. The occlusal contact area, mean and maximum occlusal pressures, and occlusal force were also measured with Dental Prescale^® 50H Type R to compare indirect masticatory abilities before the trial with those after the trial.
 As a result, in the group of 33 (17 males, 16 females) receiving DESP, the amount of sugar elution increased significantly for females from 53.7±9.4 to 58.4±5.5% and the occlusal contact area and occlusal force improved significantly for both males and females in the DESP group. The mean grip strength at the end of the trial in the DESP group improved significantly for males from 39.8±7.1 to 42.2±7.7 kg and for females from 22.9±3.9 to 24.7±3.4 kg. In the control group of 37 (17 males, 20 females) who did not receive DESP, the amount of sugar elution for males decreased significantly from 60.0±5.1 to 57.9±5.6% and mean grip strength for both males and females showed no significant difference.
 This study suggests that DESP is effective in improving the masticatory ability and grip strength among high school students.

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 Tobacco smoke causes various disorders not only of active smokers but also of passive smokers. It is also important to consider the implications of tobacco smoking on oral health.
 A general social shift, including the opinions of many dentists, towards an awareness of the consequences of tobacco is indicative of the significance of anti-tobacco policies among dental societies/associations.
 The survey was conducted in 2014 involving 43 dental societies/associations. The Japanese Association for Dental Science is composed of specialized organizations: 21 dental societies/associations, and authorized branches: 21 dental societies/associations. We received a 100% response rate. Approximately 80% of dental conference sites and other meeting venues promoted a non-smoking policy. The non-smoking requirement rate specifically for lobby areas is approximately 60%.
 Approximately half of the societies/associations surveyed (53.5%) promote smoking restrictions in all on-site areas.
 A total of 27.9% of the societies/associations have their own offices that have smoking restrictions in all areas, and 60.5% of the societies/associations commission work to external offices. The smoking restriction rate of these external offices is 88.5%, and specifically 57.7% for lobby areas.
 Only one society claims to recognize members' smoking preferences.
 Only 21.4% of those surveyed have publicly advertised their non-smoking policy, and only 7.1% have attempted to raise non-smoking awareness by producing brochures and promoting other forms of communication.
 Compared to the results of a similar survey conducted in 2004, the smoking restriction rate of lobbies has significantly increased. However, smoking is still far from being prohibited.
 From these results, it is apparent that the consequences of the issue of tobacco smoking is being increasingly recognized among dental societies/associations.
 However, further actions are needed including implementing a smoking ban in all buildings and reducing the smoking rates among dental society members.

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Abstract in Japaneses

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 Our aim was to compare the dental caries status between Japanese and Chinese children and to examine the association between the community socioeconomic status (SES) and dental caries. We made use of data collected in national surveys in Japan and China. Japanese children aged 5 and 12 years old had more filled teeth than Chinese children. As a result of this large number of filled teeth, Japanese 5-year-old children had fewer decayed teeth than Chinese children. Japanese 12-year-old children who lived in communities with a high SES had significantly fewer dental caries than those who lived in communities with a lower SES. Conversely, in China, dental caries was positively associated with the community SES. This suggests that the association between dental caries and the community SES differs among countries.

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