Hitoshi Aoyama

Relationship between smoking status and tooth loss : Findings from national databases in Japan

Background A causal association between cigarette smoking and periodontal disease has been established. The present study examined the association between smoking and tooth loss using national databases in Japan. Methods Records of the Survey of Dental Diseases and the National Nutrition Survey in 1999 were linked electronically using common identification. Records of 3,999 subjects aged older than 40 years were analyzed using logistic regression models, controlling for confounding factors, such as age, frequency of tooth brushing, body mass index, alcohol consumption, and intakes of vitamin C and E. Results Prevalence of tooth loss in terms of having less than 19 existing teeth was 37.3% overall. Smoking rates differed in males (45.6%) and females (7.8%). The prevalence of tooth loss in nonsmokers, former, and current smokers was 28.5%, 38.6%, and 36.9% in males, and 38.6%, 34.3% and 38.9% in females, respectively. Adjusted means of existing teeth controlling for confounders by smoking status were 21.5, 19.7 and 18.2 in males and 19.0, 19.2 and 16.4 in females, respectively. The association of tooth loss was non-significant in former smokers but significant in current smokers: adjusted odds ratios (95% confidence intervals) relative to nonsmokers in males and females were 1.29 (0.92-1.80) and 0.86 (0.46, 1.60) for former smokers and 2.22 (1.61-3.06) and 2.14 (1.45-3.15) for current smokers, respectively. A dose-response relationship between lifetime exposure and tooth loss was seen (P for trend <0.0001). Conclusion The findings of this cross-sectional study of a nationwide population of Japanese indicated an association between smoking and tooth loss.

Cigarette smoking and tooth loss experience among young adults: a national record linkage study

BackgroundVarious factors affect tooth loss in older age including cigarette smoking; however, evidence regarding the association between smoking and tooth loss during young adulthood is limited. The present study examined the association between cigarette smoking and tooth loss experience among adults aged 20–39 years using linked data from two national databases in Japan.MethodsTwo databases of the National Nutrition Survey (NNS) and the Survey of Dental Diseases (SDD), which were conducted in 1999, were obtained from the Ministry of Health, Labor and Welfare with permission for analytical use. In the NNS, participants received physical examinations and were interviewed regarding dietary intake and health practices including cigarette smoking, whereas in the SDD, participants were asked about their frequency of daily brushing, and received oral examinations by certified dentists. Among 6,805 records electronically linked via household identification code, 1314 records of individuals aged 20 to 39 years were analyzed. The prevalence of 1+ tooth loss was compared among non-, former, and current smokers. Multiple logistic regression models were constructed including confounders: frequency of tooth brushing, body mass index, alcohol consumption, and intake of vitamins C and E.ResultsSmoking rates differed greatly in men (53.3%) and women (15.5%). The overall prevalence of tooth loss was 31.4% (31.8% men and 31.1% women). Tooth loss occurred more frequently among current smokers (40.6%) than former (23.1%) and non-smokers (27.9%). Current smoking showed a significant association with 1+ tooth loss in men (adjusted OR = 2.21 [1.40–3.50], P = 0.0007) and women (1.70 [1.13–2.55], P = 0.0111). A significant positive exposure-related relationship between cigarette smoking status and tooth loss was observed (P for trend < 0.0001 and 0.0004 in men and women, respectively). Current smoking was also associated with the prevalence of decayed teeth (1.67 [1.28–2.20], P = 0.0002).ConclusionAn association between cigarette smoking and tooth loss was evident among young adults throughout Japan. Due to limitations of the available variables in the present databases, further studies including caries experience and its confounders should be conducted to examine whether smoking is a true risk of premature tooth loss in young adults.

Dental caries in 3-year-old children and smoking status of parents.

An association has been suggested between environmental tobacco smoke and oral disease. The present study examined the relationship between early childhood caries (ECC) and parental smoking, particularly paternal smoking, using records of 711 36-month-old children. The smoking status of parents as an independent variable was entered in the multivariable logistic regression model for caries experience as the dependent variable with confounders: sex, residential location, and possible risks of ECC such as order of birth, type of main drink, frequency of daily intake of sugar-containing snacks, daily toothbrushing by parents and use of fluoridated toothpaste. About 65% of children were caries free. Children whose parents did not smoke (CN), those in whom only the father smoked (CF), and those whose mother smoked regardless of the smoking status of the father (CM) comprised 33%, 33% and 34% respectively. The adjusted mean number [95% CI] of decayed teeth and caries experience prevalence for CN, CF and CM were 1.2 [0.8, 1.6], 1.6 [1.2, 2.0] and 2.1 [1.7, 2.5], and 25.6%, 35.3% and 45.7% respectively. The relationship between caries experience and parental smoking was significant on multivariable analysis. The adjusted OR [95% CI] of CF and CM relative to CN was 1.52 [1.01, 2.30] and 2.25 [1.51, 3.37] respectively. These results indicate the association of ECC with parental smoking, although the association with paternal smoking was weaker than with maternal smoking.

Functional tooth number and 15‐year mortality in a cohort of community‐residing older people

Background:  To study how dental status can become a predictor of overall mortality risk.

Associations between functional tooth number and physical complaints of community-residing adults in a 15-year cohort study.

Background:  Oral function influences various general health and organ diseases. We wondered if physical complaints of unknown origin were related to oral function.

Critical tooth number without subjective dysphagia

Aim:  To assess the critical tooth number (CTN) required for prevention of subjective dysphagia caused by oral impairments and to evaluate the relationship between this CTN and mortality.