Matti Knuuttila

Association between body weight and periodontal infection

BACKGROUNDnBesides being a risk factor for cardiovascular diseases, certain cancers and type II diabetes, obesity has been suggested to be a risk factor for periodontitis. A number of epidemiological studies have studied the association between obesity and periodontitis, but the results have been partly inconclusive. The aim of this study was to examine the association of body weight with periodontal infection.nnnMATERIAL AND METHODSnThe association between body weight and periodontal infection was examined using a nationally representative Health 2000 Health Examination Survey. The study was based on a subpopulation of dentate non-diabetic subjects aged 30-49 (n=2841). Periodontal infection was measured by the number of teeth with periodontal pockets of 4 mm or deeper and 6 mm or deeper. Body weight was measured using body mass index (BMI).nnnRESULTSnWe detected a weak exposure-response association of BMI with teeth with deepened periodontal pockets after controlling for smoking habits by restricting the sample to subjects who have never smoked and for other potential confounders by including them in the multivariate models.nnnCONCLUSIONSnThe results showed an association between body weight and periodontal infection among the non-diabetic, non-smoking population aged 30-49. Additional research is needed to determine the nature of this association.

Metabolic Syndrome, Periodontal Infection, and Dental Caries

Only a few studies have examined the association of metabolic syndrome with periodontal infection and dental caries. The aim in this study was to examine the association of metabolic syndrome with periodontal infection and dental caries using the European Group for the Study of Insulin Resistance (EGIR) definition and its separate components. This study population consisted of dentate, non-diabetic individuals aged 30 to 64 years (N = 2050) who had never smoked. Relative risks (RR) were estimated with Poisson regression models. Metabolic syndrome was associated with teeth with deepened periodontal pockets 4 mm deep or deeper [adjusted RR 1.19 (95% CI 1.01-1.42)], with pockets 6 mm deep or deeper [adjusted RR 1.50 (95% CI 0.96-2.36)], and carious teeth [adjusted RR 1.25 (95% CI 0.93-1.70)]. The results suggest that metabolic syndrome or some of its components are associated weakly with periodontal infection.

Association between serum lipid levels and periodontal infection

OBJECTIVEnThe aim of the study was to investigate the association between serum lipids and periodontal infection and the role of serum lipids in the association between body weight and periodontal infection.nnnMATERIAL AND METHODSnThe Health 2000 Health Examination Survey, which included 8028 subjects aged 30 or older living in continental Finland. This study was based on a subpopulation of dentate, non-diabetic subjects who had never smoked and were aged under 50 years (n=1297). Periodontal infection was defined as the presence of teeth with deepened periodontal pockets. Serum levels of triglycerides, high-density lipoprotein (HDL)-cholesterol and low-density lipoprotein (LDL)-cholesterol were analysed enzymatically.nnnRESULTSnWe found no consistent association between serum lipid levels and periodontal infection among normoweight subjects. There was an association of high serum triglycerides and low HDL with periodontal infection among obese subjects. The association between body mass index and periodontal infection was not essentially affected by serum lipids.nnnCONCLUSIONnIn this study population serum lipid levels were not associated with periodontal infection among normoweight subjects. Obese subjects with a high serum triglyceride level and/or a low HDL-cholesterol level could be at higher risk of periodontal infection. Our results suggest that the association between body weight and periodontal infection was mainly mediated through a mechanism other than serum lipids.

Education level and oral health in Finnish adults: evidence from different lifecourse models

AIMnTo assess the relationship between education level and several oral health outcomes in Finnish adults, using three conceptual lifecourse models.nnnMATERIALS AND METHODSnThis study analysed data from 7112 subjects, aged 30 years or over, who participated in the nationally representative Finnish Health 2000 Survey. Parental and own education levels were the childhood and adulthood socioeconomic measures, respectively. Oral health was indicated by edentulousness, perceived oral health and levels of dental caries and periodontal disease. Three conceptual lifecourse models, namely critical period, accumulation and social trajectories, were separately tested in regression models.nnnRESULTSnIn line with the critical period model, parental and own education levels were independently associated with oral health after mutual adjustment. There was also a graded linear relationship between the number of periods of socioeconomic disadvantage and oral health, corresponding to the accumulation model. Gradual declines in oral health were evident between social trajectories from persistently high to upwardly mobile, downwardly mobile and persistently low groups.nnnCONCLUSIONnThere was similar support for the lifecourse models of critical period, accumulation and social trajectories. They collectively contribute to a better understanding of oral health inequalities.

Relationship of depressive symptoms to edentulousness, dental health, and dental health behavior

We investigated the relationship of edentulousness, dental health, and dental health behavior to depressive symptoms in the 55-year-old population of Oulu (a medium-sized Finnish town), 780 of whom (78%) participated. The dental examination included an assessment of oral health status. Depressive symptoms were determined with the Zung Self-Rating Depression Scale (ZSDS). The participants were also asked about their dental health behavior, smoking habits, health, life satisfaction, and factors related to their work. Depressive symptoms were associated with edentulousness among non-smoker men. When further evaluated by logistic regression analysis, edentulousness was independently associated with depressive symptoms in this subpopulation (odds ratio = 6.4, confidence interval = 1.4–29.2) after adjusting for confounding factors. Depressive symptoms were not associated with dental caries, periodontal status, or number of teeth. The dentate women with high rates of depressive symptoms had a more negative attitude towards preserving their natural teeth, used sugary products more frequently, reported a longer time since their last dental visit, and tended to have a lower percentage of filled tooth surfaces than the non-depressed dentate women. The aspect of depression should be borne in mind by dentists when treating edentulous patients. On the other hand, certain subgroups of depressed patients might benefit from dental implant therapy. Thus, the importance of teamwork between clinicians, psychiatrists, and dentists is emphasized.

Optimism and Life Satisfaction as Determinants for Dental and General Health Behavior—Oral Health Habits Linked to Cardiovascular Risk Factors

Oral infections and cardiovascular diseases share common biological and behavioral risk factors. Psychosocial determinants could act as a link between general health behavior and dental health behavior. Our objective was to study optimism and life satisfaction as determinants of general and dental health behavior and to evaluate whether these are connected with cardiovascular risk factors and dental diseases. The 1966 Northern Finland Birth Cohort (N = 12,058) is a general population birth cohort. In a postal questionnaire, respondents (N = 8690) were asked about their health behavior and dental status. Cardiovascular risk factors were assessed in health examinations (N = 6033). Generalized linear regression models were used in analysis. The results showed that health orientation increases with strengthening life satisfaction and optimism. Dental health behavior and general health behavior were associated with both cardiovascular risk factors and self-reported dental diseases, which support the assumption that they share a common behavioral background.

Relationship between cognitive impairment and oral health: results of the Health 2000 Health Examination Survey in Finland

Objective. The aim was to study oral health in relation to cognitive impairment in the general population. Material and Methods. The study population comprised 2320 persons aged 55 years or older who participated in a nationally representative Health 2000 Health Examination Survey in Finland. The data were collected by interviews and clinical oral examinations. Cognition was assessed using a shortened version of the Mini-Mental State Examination (score 0–16). Poisson regression models were used to estimate the relative risk (RR) for continuous variables and logistic regression models to estimate the odds ratio (OR) for dichotomized variables. Results. The results show that individuals with cognitive impairment have more carious teeth (MMSE 11-10: RR: 1.3, CI: 0.9–1.7, MMSE 9-0: RR: 1.5 CI: 1.0–2.4) than healthy persons. Furthermore, compared to cognitively healthy subjects, those with MMSE 9–0 more often have no teeth and no dentures (OR: 5.2, CI: 1.0–26.6) and less often good denture hygiene (OR: 0.4, CI: 0.2–0.7). Conclusion. Cognitively impaired subjects among older adults in Finland have more carious teeth, are more often edentulous without using a denture, and have poorer denture hygiene than cognitively healthy persons.

Sense of coherence and oral health in dentate adults: findings from the Finnish Health 2000 survey.

AIMnTo assess the relationship between sense of coherence (SOC) and oral health, and the role of oral health-related behaviours in this relationship.nnnMATERIALS AND METHODSnThis is a cross-sectional study of 5401 dentate adults who participated in the nationally representative Health 2000 Survey in Finland. The survey gathered information on SOC, demographic characteristics, education, income, pre-existing diabetes, daily smoking, dental attendance, toothbrushing frequency and sugar intake frequency. Oral health was assessed through clinical outcomes, such as number of teeth, number of decayed teeth and extent of periodontal pockets and perceived oral health.nnnRESULTSnA strong SOC was related to having more teeth, fewer decayed teeth, lower extent of periodontal pockets and good perceived oral health after adjustment for confounders, such as demographic and socioeconomic factors (all p0.003). These associations were attenuated but remained significant after further adjustment for potential mediators (oral health-related behaviours), except for the association of SOC with the extent of periodontal pockets, which was fully accounted for by pre-existing diabetes, oral health-related behaviours and dental plaque (p=0.549).nnnCONCLUSIONnSOC is positively associated with various aspects of adult oral health, in part because of the better oral health-related behaviours among people with a strong SOC.

Role of serum cytokines tumour necrosis factor-α and interleukin-6 in the association between body weight and periodontal infection

AIMnTo study the role of serum cytokines tumour necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) as potential mediators in the association between body weight and periodontal infection among an adult population.nnnMATERIAL AND METHODSnThis study was based on a subpopulation of the Health 2000 Health Examination Survey, which included dentate non-diabetic, non-rheumatic subjects, aged between 45 and 64 years, who had never smoked and whose serum levels of TNF-alpha and IL-6 were analysed and whose periodontal status was clinically determined (effective n=425). The number of teeth with periodontal pockets of 4 mm or more and the number of teeth with periodontal pockets of 6 mm or more were used as outcome variables. Relative risks and 95% confidence intervals were estimated using Poisson regression models.nnnRESULTSnSerum IL-6, but not TNF-alpha associated with teeth with deepened periodontal pockets. Multivariate models showed that IL-6, but not TNF-alpha, could mediate the effect of body weight on periodontium.nnnCONCLUSIONnIn this population of non-diabetic and non-rheumatic subjects, who had never smoked, serum IL-6 was associated with periodontal infection. The results suggest that serum IL-6 could be one mediating factor that connects body weight and periodontal infection.

IMPROVED BONE BIOMECHANICAL PROPERTIES IN RATS AFTER ORAL XYLITOL ADMINISTRATION

Abstract. The effects of 5, 10, and 20% dietary xylitol supplementations on the biomechanical properties, histological architecture, and the contents of collagen, pyridinoline, and deoxypyridinoline in long bones of rats were studied. Tibiae were used for the three-point bending test, and femurs were used for the torsion and loading test of the femoral neck. The 10 and 20% oral xylitol administrations caused a significant increase of tibial stress, femoral shear stress, and stress of the femoral neck as compared with the controls. Parallel, but not significant, effects were also seen in the 5% xylitol supplementation group. No significant differences in strain or Youngs modulus of the tibiae were detected between the groups. An increased shear modulus of elasticity in femurs was detected in the 20% supplementation group as compared with the controls. The histomorphometrical data for the secondary spongiosa of the proximal tibia revealed that trabecular bone volume was significantly greater in all dietary xylitol supplementation groups as compared with the controls. The bone volume increased along with increasing xylitol content. No significant differences between the groups were detected concerning the amount of collagen per dry weight of organic matrix, the concentrations of pyridinoline or deoxypyridinoline in collagen, or the ratio of these crosslinks. This suggests no xylitol-dependent selective changes in these structures of bone collagen. In conclusion, dietary xylitol supplementation in rats improves the biomechanical properties of bone and increases the trabecular bone volume dose dependently.