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


METHODS
Two 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.


RESULTS
Smoking 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).


CONCLUSIONS
An 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.
Ojima
Miki
M
Department of Preventive Dentistry, Graduate School of Dentistry, Osaka University, Osaka, Japan. ojima@dent.osaka-u.ac.jp
Hanioka
Takashi
T
Tanaka
Keiko
K
Aoyama
Hitoshi
H
D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D016208:Databases, Factual; D005260:Female; D006306:Health Surveys; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008498:Medical Record Linkage; D009910:Oral Hygiene; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D016388:Tooth Loss / Q000453:epidemiology*; D014099:Toothbrushing / Q000706:statistics & numerical data