Interaction between serum vitamin C levels and smoking on the periodontal condition in older adults.

BACKGROUND AND OBJECTIVES: Several epidemiological studies have reported that smokers have a higher prevalence and severity of periodontal disease than do nonsmokers, and that smoking negatively affects nutritional status and is associated with a reduced intake of antioxidants, particularly vitamin C. The present investigation aimed to examine the relationship between serum vitamin C levels and smoking and its influence on the periodontal condition in older adults. MATERIALS AND METHODS: A total of 353 respondents met the inclusion criteria and were enrolled in the present study. The periodontal status of the study participants was determined through examinations of one or more residual teeth, which included a measurement of the probing pocket depth (PPD) and clinical attachment level (CAL) at six regions of each tooth. Blood samples were collected during the dental examinations and then sent to a laboratory to evaluate serum vitamin C and cotinine levels. A serum cotinine concentration of 100 ng/ml was considered a relevant threshold for active smoking. After dividing the participants into two groups according to serum cotinine levels, Poisson regression analysis was carried out to compare vitamin C levels with the prevalence rate ratio (PRR) for periodontal condition markers for each group based on serum cotinine levels. RESULTS: We evaluated differences in the PRR of serum vitamin C tertiles between participants with high (≥100 ng/ml) or low (<100 ng/ml) serum cotinine levels after adjusting for sex, the use of interdental brushes or dental floss, and the number of teeth. A negative tendency between the PRR of vitamin C tertiles for the PPD or CAL was seen for both groups. Especially, a bigger difference was observed in the group with high serum cotinine levels. The PRR of the first tertiles in the high serum cotinine group was 5.03, compared with 2.69 in the low serum cotinine group (relative risk: 1.9). CONCLUSION: The results of this study suggest a potential association between vitamin C levels and the periodontal condition, which may be influenced by smoking status.

Effects of Oral Function Training and Oral Health Status on Physical Performance in Potentially Dependent Older Adults.

This study aimed to evaluate the effects of an oral function training program and indicators of oral health status on improvements in physical performance induced by physical function training in dependent older adults. The participants were 131 potentially dependent older adults (age: ≥65 years) who were randomly divided into two groups: an oral intervention and a control group. All participants underwent physical function training, but only the intervention group took part in the oral function training program. In total, 106 participants completed all of the survey components (60 and 46 participants from the intervention and control groups, respectively). The measures of physical fitness examined included the one-leg standing time with eyes open (OLST) and the timed up and go test (TUG). Logistic regression analyses were carried out to determine the effects of the oral function intervention and health status on physical fitness. The results revealed that the oral function intervention significantly improved OLST and TUG times. These findings suggest that evaluations of oral health status and interventions aimed at activating oral functions are associated with improvements in physical fitness among potentially dependent older adults.