Sleep apnea symptoms and risk of temporomandibular disorder: OPPERA cohort

The authors tested the hypothesis that obstructive sleep apnea (OSA) signs/symptoms are associated with the occurrence of temporomandibular disorder (TMD), using the OPPERA prospective cohort study of adults aged 18 to 44 years at enrollment (n = 2,604) and the OPPERA case-control study of chronic TMD (n = 1,716). In both the OPPERA cohort and case-control studies, TMD was examiner determined according to established research diagnostic criteria. People were considered to have high likelihood of OSA if they reported a history of sleep apnea or ≥ 2 hallmarks of OSA: loud snoring, daytime sleepiness, witnessed apnea, and hypertension. Cox proportional hazards regression estimated hazard ratios (HRs) and 95% confidence limits (CL) for first-onset TMD. Logistic regression estimated odds ratios (OR) and 95% CL for chronic TMD. In the cohort, 248 individuals developed first-onset TMD during the median 2.8-year follow-up. High likelihood of OSA was associated with greater incidence of first-onset TMD (adjusted HR = 1.73; 95% CL, 1.14, 2.62). In the case-control study, high likelihood of OSA was associated with higher odds of chronic TMD (adjusted OR = 3.63; 95% CL, 2.03, 6.52). Both studies supported a significant association of OSA symptoms and TMD, with prospective cohort evidence finding that OSA symptoms preceded first-onset TMD.

Oral health-related quality of life is important for patients, but what about populations?

OBJECTIVES

To review population-based research into oral health-related quality of life.

METHODS

Narrative review of selected publications.

RESULTS

In the 1970s, there were two incentives to assess nonclinical aspects of health: (i) a desire to understand the impacts of disease on individuals' quality of life; and (ii) a search for population-level measures that might better quantify the impact of health care systems on populations. Dental researchers responded to those incentives, creating dozens of questionnaires that assess individuals' ratings of subjective oral health and quality of life. This has been a boon for clinical dental research, for example, by showing marked improvements in subjective oral health in patients receiving implant-supported dentures. Also, health surveys show poorer subjective oral health among disadvantaged population groups. However, the same measures show only modest benefits of general dental care. Furthermore, several population surveys show that today's young adults, who grew up with widespread exposure to preventive dental programs, have poorer subjective oral health than earlier generations that experienced unprecedented levels of oral disease. Yet to materialize is the hope that 'socio-dental indicators' of subjective oral health might provide a meaningful metric to demonstrate population-level benefits of dental care. A fundamental limitation is that population health is a contextual measure, not merely the aggregated health status of individuals within the population.

CONCLUSION

While researchers have successfully broken with clinical dogma by assessing subjective dimensions of individuals' oral health, they have failed to explicitly ask people to assess the oral health of the community in which they live.

Chronic HPA axis response to stress in temporomandibular disorder

PURPOSE

Perceived stress is associated with temporomandibular disorder (TMD), but whether cortisol levels are elevated in individuals with TMD is unknown. We hypothesized that cortisol concentration, a biomarker of hypothalamic-pituitary-adrenal (HPA) axis function, was elevated in TMD cases relative to controls, and that perceived stress was positively correlated with cortisol concentration.

METHODS

In this case control study, TMD case status was determined by examiners using TMD Research Diagnostic Criteria. Participants (n=116) aged 18 to 59 years were recruited from within a 50 mile radius of the University of North Carolina at Chapel Hill. Following examination, cases (n=45) and controls (n=71) completed the 14-item Perceived Stress Scale using a reference interval of the past 3 months. Approximately 100 strands of hair were cut from the posterior vertex segment of their scalp. The 3 centimeters of hair most proximal to the scalp was analyzed with a commercially available salivary cortisol enzyme immunoassay adapted for hair cortisol. This length corresponds to the last 3 months of systemic HPA axis activity.

RESULTS

TMD cases perceived higher stress than controls (p=0.001). However, hair cortisol concentration was lower in TMD cases than controls (p<0.001). The correlation coefficient revealed a weak negative relationship (r=-0.188) between perceived stress and hair cortisol concentration (p=0.044). In analysis stratified by case status, the relationship of perceived stress and hair cortisol concentration was non-significant for cases (p=0.169) and controls (p=0.498).

CONCLUSION

Despite greater perceived stress, TMD cases had lower hair cortisol concentrations than controls and the 2 measures of stress were weakly and negatively correlated.

Effects of fluoridated drinking water on dental caries in Australian adults

Systematic reviews produce conflicting conclusions regarding dental caries-preventive effects of water fluoridation in adults. The authors investigated the relationship using data from the nationally representative 2004-2006 Australian National Survey of Adult Oral Health. Effects were compared between the pre-fluoridation cohort born before 1960 (n = 2,270) and the cohort born between 1960 and 1990 (n = 1,509), when widespread implementation of fluoridation increased population coverage from < 1% to 67%. Residential history questionnaires determined the percentage of each person's lifetime exposed to fluoridated water. Examiners recorded decayed, missing, and filled teeth (DMF-Teeth) and decayed and filled tooth surfaces (DF-Surfaces). Socio-demographic and preventive dental behaviors were included in multivariable least-squares regression models adjusted for potential confounding. In fully adjusted models, > 75% of lifetime exposure to fluoridation relative to < 25% of lifetime exposure was associated with 11% and 10% fewer DMF-Teeth in the pre-1960 (p < .0001) and 1960-1990 cohorts (p = .018), respectively. Corresponding reductions in DF-Surfaces were 30% (p < .001) and 21% (p < .001). Findings for intermediate fluoridation exposure suggested a dose-response relationship. Results were consistent in sensitivity analyses accounting for missing data. In this nationally representative sample of Australian adults, caries-preventive effects of water fluoridation were at least as great in adults born before widespread implementation of fluoridation as after widespread implementation of fluoridation.

Preclinical episodes of orofacial pain symptoms and their association with health care behaviors in the OPPERA prospective cohort study

The course of preclinical pain symptoms sheds light on the etiology and prognosis of chronic pain. We aimed to quantify rates of developing initial and recurrent symptoms of painful temporomandibular disorder (TMD) and to evaluate associations with health behaviors. In the OPPERA prospective cohort study, 2,719 individuals aged 18 to 44years with lifetime absence of TMD when enrolled completed 25,103 quarterly (3-monthly) questionnaires during a median 2.3-year follow-up period. Questionnaires documented TMD symptom episodes, headache, other body pain, health care attendance, and analgesic use, and. Kaplan-Meier methods for clustered data estimated symptom-free survival time. Multivariable models assessed demographic variation in TMD symptom rates and evaluated associations with health care and analgesic use. One-third of the study subjects developed TMD symptoms and for a quarter of symptomatic episodes, pain intensity was severe. Initial TMD symptoms developed at an annual rate of 18.8 episodes per 100 persons. The annual rate more than doubled for first-recurrence and doubled again for second or subsequent recurrence such that, 1year after first recurrence, 71% of study subjects experienced a second recurrence. The overall rate increased with age and was greater in African Americans and lower in Asians relative to those of white race/ethnicity. The probability of TMD symptoms was strongly associated with concurrent episodes of headache and body pain and with past episodes of TMD symptoms. Episodes of TMD symptoms, headache, and body pain were associated with increases of ∼10% in probability of analgesic use and health care attendance. Yet, even when TMD, headache, and body pain occurred concurrently, 27% of study subjects neither attended health care nor used analgesics.

Surface-specific efficacy of fluoride varnish in caries prevention in the primary dentition: results of a community randomized clinical trial

OBJECTIVES

Fluoride varnish (FV) is efficacious in caries prevention although its effects among different tooth surfaces are poorly understood. This study sought to determine the extent to which caries-preventive effects of a community intervention that included FV application among preschool-aged children varied according to primary tooth anatomy and baseline tooth pathology.

METHODS

Secondary analysis was undertaken of data from a community-randomized controlled trial among 543 3- to 5-year-old Aboriginal children in 30 Northern Territory Australian communities. Children in intervention communities received community health promotion and FV application once every 6 months. Net caries (d(3)mfs) risk and 95% confidence limits (CL) were estimated for the control and intervention arms, and stratified according to tooth anatomy/location and baseline pathology (sound, enamel opacity, hypoplastic defect or precavitated carious lesion). The intervention's efficacy was quantified using generalized estimating equation modeling accounting for study design and clustering. The assumption of efficacy homogeneity was tested using a Wald χ(2) test with a p < 0.2 criterion and post hoc pairwise comparisons.

RESULTS

The intervention resulted in a 25% reduction (relative risk, RR = 0.75; 95% CL = 0.71, 0.80) in the 2-year surface-level caries risk. There was substantial heterogeneity in FV efficacy by baseline surface pathology: RRs were 0.73 for sound, 0.77 for opaque, 0.90 for precavitated, and 0.92 for hypoplastic surfaces. Among sound surfaces, maxillary anterior facials received significantly more benefit (RR = 0.62) compared to pits and fissures (RR = 0.78).

CONCLUSION

The intervention had greatest efficacy on surfaces that were sound at baseline. Among those sound surfaces, maxillary anterior facials received most caries-preventive benefit.

Valuation of tobacco control policies by the public in North Carolina: comparing perceived benefit with projected cost of implementation

BACKGROUND

After 40 years of continuous decline, smoking rates in the United States have stabilized signaling a challenge for tobacco control. Renewed decline may be guided by public opinion where support for tobacco control is strong. This study sought the public's preferences about tobacco control strategies.

METHODS

This contingent valuation study investigated whether the public's valuations of 2 tobacco control policies outweighed their implementation costs. In a hypothetical referendum, a representative sample of North Carolinians aged 45-64 years (n = 644) was asked to indicate whether they would prefer a policy that would halve the youth smoking rate or one that would reduce smoking-related deaths by 10%, and to indicate how much additional tax they would be willing to pay to implement their preferred policy. This willingness-to-pay value formed the perceived "benefit" component in a cost-benefit analysis. Costs to halve youth smoking were calculated from evidence about the resources required to increase the state tobacco excise tax. Costs to reduce tobacco-related deaths were based on evidence about the resources required for a counseling quitline offering free nicotine replacement therapy.

RESULTS

The majority (85%) of respondents voted to halve the youth smoking rate. The mean maximum amount per person that voters were willing to pay in 1 year to do that was $14.90 (95% CI, $10.10-$19.60), and the maximum amount per person they were willing to pay in 1 year to reduce smoking-related deaths was $13.70 (95% CI, $2.10-$25.40). When aggregated to the North Carolina population aged 45-64 years (N = 2,400,144), the perceived benefit of halving youth smoking was $35.8 million. Implementation of a program to achieve this outcome would cost $109.8 million. Aggregating to the same population, the perceived benefit of a 10% reduction in tobacco-related deaths was $32.9 million, an amount that exceeds the $12.8 million estimated cost of achieving the outcome.

CONCLUSION

A counseling quitline with free nicotine replacement therapy would achieve a positive net benefit.

Is poor access to dental care why people outside capital cities have poor oral health?

BACKGROUND

Why oral health status outside capital cities is poorer than that in capital cities has not been satisfactorily explained. The aim of this study was to determine if the reason was poorer access to dental care.

METHODS

Data were obtained from the Australian National Survey of Adult Oral Health (2004-06). Oral health status was measured by DMFT Index, and numbers of decayed, missing and filled teeth. A two-step analysis was undertaken: comparing the dependent variables by location, socio-demographic confounders and preventive dental behaviours, and then including six access to dental care variables.

RESULTS

Of the 14 123 people interviewed, 5505 were examined, and 4170 completed the questionnaire. With socio-economic parameters in the first regression model, non-capital city people had higher DMFT (regression coefficient = 1.15, p < 0.01), more decayed (0.42, p < 0.01) and missing teeth (0.85, p < 0.01), but not filled teeth (-0.11, p = 0.71), than capital city based people. In the second step analysis, non-capital city people still had a greater DMFT (1.01, p < 0.01), more decayed (0.27, p = 0.03) and missing teeth (0.74, p < 0.01), but not filled teeth (0.00, p = 0.99) than capital city based people.

CONCLUSIONS

Access to dental care was not the only reason why people outside capital cities have poorer oral health than people living in capital cities.

Potential autonomic risk factors for chronic TMD: descriptive data and empirically identified domains from the OPPERA case-control study

Several case-control studies have been conducted that examine the association between autonomic variables and persistent pain conditions; however, there is a surprising dearth of published studies in this area that have focused on temporomandibular disorders (TMD). The current study presents autonomic findings from the baseline case-control study of the OPPERA (Orofacial Pain: Prospective Evaluation and Risk Assessment) cooperative agreement. Measures of arterial blood pressure, heart rate, heart rate variability, and indirect measures of baroreflex sensitivity were assessed at rest and in response to a physical (orthostatic) and psychological (Stroop) stressors in 1,633 TMD-free controls and 185 TMD cases. In bivariate and demographically adjusted analyses, greater odds of TMD case status were associated with elevated heart rates, reduced heart rate variability, and reduced surrogate measures of baroreflex sensitivity across all experimental procedures. Principal component analysis was undertaken to identify latent constructs revealing 5 components. These findings provide evidence of associations between autonomic factors and TMD. Future prospective analyses in the OPPERA cohort will determine if the presence of these autonomic factors predicts increased risk for developing new onset TMD.

PERSPECTIVE

This article reports autonomic findings from the OPPERA Study, a large prospective cohort study designed to discover causal determinants of TMD pain. Findings indicate statistically significant differences between TMD cases and controls across multiple autonomic constructs at rest and during both physical and psychologically challenging conditions. Future analyses will determine whether these autonomic factors increase risk for new onset TMD.

Pain sensitivity risk factors for chronic TMD: descriptive data and empirically identified domains from the OPPERA case control study

Many studies report that people with temporomandibular disorders (TMD) are more sensitive to experimental pain stimuli than TMD-free controls. Such differences in sensitivity are observed in remote body sites as well as in the orofacial region, suggesting a generalized upregulation of nociceptive processing in TMD cases. This large case-control study of 185 adults with TMD and 1,633 TMD-free controls measured sensitivity to painful pressure, mechanical cutaneous, and heat stimuli, using multiple testing protocols. Based on an unprecedented 36 experimental pain measures, 28 showed statistically significantly greater pain sensitivity in TMD cases than controls. The largest effects were seen for pressure pain thresholds at multiple body sites and cutaneous mechanical pain threshold. The other mechanical cutaneous pain measures and many of the heat pain measures showed significant differences, but with lesser effect sizes. Principal component analysis (PCA) of the pain measures derived from 1,633 controls identified 5 components labeled: 1) heat pain ratings; 2) heat pain aftersensations and tolerance; 3) mechanical cutaneous pain sensitivity; 4) pressure pain thresholds; and 5) heat pain temporal summation. These results demonstrate that compared to TMD-free controls, chronic TMD cases are more sensitive to many experimental noxious stimuli at extracranial body sites, and provide for the first time the ability to directly compare the case-control effect sizes of a wide range of pain sensitivity measures.

PERSPECTIVE

This article describes experimental pain sensitivity differences between a large sample of people with chronic TMD and non-TMD controls, using multiple stimulus modalities and measures. Variability in the magnitude and consistency of case-control differences highlight the need to consider multiple testing measures to adequately assess pain processing alterations in chronic pain conditions.

Potential psychosocial risk factors for chronic TMD: descriptive data and empirically identified domains from the OPPERA case-control study

Case-control studies have consistently associated psychosocial factors with chronic pain in general, and with temporomandibular disorders (TMD) specifically. Moreover, a handful of prospective studies suggest that preexisting psychosocial characteristics represent risk factors for new onset TMD. The current study presents psychosocial findings from the baseline case-control study of the Orofacial Pain Prospective Evaluation and Risk Assessment (OPPERA) cooperative agreement. For this study, 1,633 TMD-free controls and 185 TMD cases completed a battery of psychosocial instruments assessing general psychosocial adjustment and personality, affective distress, psychosocial stress, somatic awareness, and pain coping and catastrophizing. In bivariate and demographically adjusted analyses, odds of TMD were associated with higher levels of psychosocial symptoms, affective distress, somatic awareness, and pain catastrophizing. Among controls, significant gender and ethnic group differences in psychosocial measures were observed, consistent with previous findings. Principal component analysis was undertaken to identify latent constructs revealing 4 components: stress and negative affectivity, global psychosocial symptoms, passive pain coping, and active pain coping. These findings provide further evidence of associations between psychosocial factors and TMD. Future prospective analyses in the OPPERA cohort will determine if the premorbid presence of these psychosocial factors predicts increased risk for developing new onset TMD.

PERSPECTIVE

This article reports baseline psychosocial findings from the OPPERA Study, a large prospective cohort study designed to discover causal determinants of TMD pain. Findings indicate significant differences between TMD cases and TMD-free controls across multiple psychosocial constructs, and future analyses will determine whether these psychosocial factors increase risk for new onset TMD.

Role of allostatic load in sociodemographic patterns of pain prevalence in the U.S. population

Persistent stressors associated with sociodemographic disadvantage exert a physiologic toll, labeled "allostatic load," that contributes to disparities in some health conditions. We investigated the contribution of allostatic load to pain prevalence in U.S. adults. Interviews with 14,184 adults in the 1999-2004 National Health and Nutrition Examination Survey asked about severe headache, pain that lasted >24 hours, and widespread pain. Ten biomarkers of allostatic load were quantified from blood (glycated hemoglobin), serum (C-reactive protein, homocysteine, cholesterol, triglycerides), urine (creatinine, albumin), and physical measurements (body mass index, systolic and diastolic blood pressure). Log-binomial regression models estimated prevalence ratios (PRs) and 95% confidence intervals (95% CIs). Prevalence ranged from 3.4% for widespread pain to 26.9% for pain >24 hours. After adjustment for demographic characteristics, low income was associated with greater prevalence of pain >24 hours (PR = 1.65, 95% CI = 1.49, 1.83), severe headache (PR = 2.05, 95% CI = 1.68, 2.50), and widespread pain (PR = 3.67, 95% CI = 2.56, 5.27). Racial/ethnic minorities had lower prevalence of all 3 pain conditions than non-Hispanic whites. While greater allostatic load was associated with elevated prevalence of pain, allostatic load did not meaningfully attenuate PRs associated with income or race/ethnicity. We conclude that greater pain prevalence among low-income groups is not explained by greater allostatic load.

PERSPECTIVE

In U.S. adults, pain occurs more frequently in lower-income groups, although the relationship is not attributable to their experience of greater allostatic load. While allostatic load contributes to population variation in pain, other etiologic mechanisms contributing to pain are needed to account for income disparities in pain.

National prevalence of oral HPV infection and related risk factors in the U.S. adult population

This article reviews the rapidly growing evidence that oral human papilloma viruses (HPV) infection contributes to the risk of oral squamous cell carcinoma. It also reports the first nationally representative estimates of oral HPV prevalence in the United States adult population. An estimated 7.3% (95% CI: 6.0, 8.9) of the U.S. population had one or more oral HPV types detected in oral rinse; 3.1% (95%CI: 2.4, 3.9) of the U.S. population had one or more oncogenic HPV types. A substantial excess risk of HPV infection in men is not explained by education, smoking, age of sexual debut, or number of lifetime sex partners. Based on the published finding from a case-control study, where there was an odds ratio of 2.6 (95% CI: 1.5, 4.2) for the association of head and neck cancer oncogenic oral HPV infection, the estimated population attributable risk for head and neck cancer in the U.S. population was 4.7%. In other words, there would be a 4.7% reduction in incidence rate of head and neck cancer in the United States if oncogenic HPV infection could be prevented. The results also provide population data that help evaluate the likely public health benefits of prophylactic vaccination against oral HPV acquisition.

Excess risk of temporomandibular disorder associated with cigarette smoking in young adults

Evidence suggests that the effect of cigarette smoking on chronic pain is stronger in younger than older adults. This case-control study investigated whether age modified an effect of smoking on temporomandibular disorder (TMD) in 299 females aged 18 to 60 years. It also investigated the extent to which this relationship was explained by psychological profile, inflammatory response, and allergy. Cases were defined using the Research Diagnostic Criteria for Temporomandibular Disorders based on clinical examination. Psychological profile was evaluated using standardized instruments. Inflammatory response was evaluated with 11 cytokines isolated in plasma. History of allergy conditions was self-reported. Odds ratios (ORs) for the effect of smoking were calculated using binary logistic regression. Stratified analyses and the likelihood ratio test examined effect modification by smoking. Compared with nonsmokers, ever smokers aged <30 years had higher odds of TMD (OR = 4.14, 95% CI: 1.57, 11.35) than older adults (OR = 1.23, 95% CI: .55, 2.78) (P (effect modification) = .038). Adjustment for psychological profile, cytokines, and history of allergy-like conditions attenuated the effect by 45% to statistical nonsignificance. The main finding was reproduced with secondary analyses of 2 nationally representative surveys of adults conducted in the US and Australia.

PERSPECTIVE

This study showed that smoking was associated with TMD risk in females, but only in young adulthood. It replicated this finding in 2 nationally representative surveys of females in the US and Australia. Findings may alert clinicians to recognize that smoking is a concern for TMD in younger female patients.

The relationship between dental care and perceived oral health impacts

BACKGROUND

Knowledge of the effect of dental care and dental visiting behavior on oral health impacts is important for effective resource allocation.

OBJECTIVE

To determine the association between dental care, including the reason for dental attendance and time since last dental visit, with perceived oral health impacts among Australian adults.

METHODS

Data were obtained from the Australian National Survey of Adult Oral Health 2004/06. Analysis was limited to 4,170 dentate adults who answered the Oral Health Impact Profile (OHIP-14) questions. Prevalence of frequent impacts was defined as the percentage of people reporting 'fairly often' or 'very often' to one or more of the OHIP-14 questions.

RESULTS

Over half the dentate Australians (63.0%) visited a dentist in the past year. Unadjusted analysis showed a statistically significant association between the prevalence of frequent impacts and receipt of: extractions (prevalence ratio = 1.7, 95% CI = 1.2-2.2), scale/clean (0.7, 0.5-0.8), and denture care (1.6, 1.1-2.4). After adjustment for the usual reason for dental attendance there was no effect of any of the three treatments or the time since last visit on the prevalence of frequent impacts.

CONCLUSION

The usual reason for dental attendance, and not the time since last visit or the type of dental care supplied, accounted for differences in perceived oral health impacts.

Study methods, recruitment, sociodemographic findings, and demographic representativeness in the OPPERA study

This paper describes methods used in the project "Orofacial Pain Prospective Evaluation and Risk Assessment" (OPPERA) and evaluates sociodemographic characteristics associated with temporomandibular disorders (TMD) in the OPPERA case-control study. Representativeness was investigated by comparing sociodemographic profiles of OPPERA participants with population census profiles of counties near study sites and by comparing age and gender associations with TMD in OPPERA and the 2007 to 2009 US National Health Interview Survey. Volunteers aged 18 to 44 years were recruited at 4 US study sites: 3,263 people without TMD were enrolled into the prospective cohort study; 1,633 of them were selected as controls for the baseline case-control study. Cases were 185 volunteers with examiner-classified TMD. Distributions of some demographic characteristics among OPPERA participants differed from census profiles, although there was less difference in socioeconomic profiles. Odds of TMD was associated with greater age in this 18 to 44 year range; females had 3 times the odds of TMD as males; and relative to non-Hispanic-Whites, other racial groups had one-fifth the odds of TMD. Age and gender associations with chronic TMD were strikingly similar to associations observed in the US population. Assessments of representativeness in this demographically diverse group of community volunteers suggest that OPPERA case-control findings have good internal validity.

PERSPECTIVE

Demographic associations with TMD were consistent with population benchmarks and with other studies, suggesting broad applicability of these OPPERA findings. Greater occurrence of TMD in non-Hispanic-Whites than in other racial/ethnic groups and the lack of a socioeconomic gradient contradicts the disparities seen in many other health conditions.

Cytokine biomarkers and chronic pain: association of genes, transcription, and circulating proteins with temporomandibular disorders and widespread palpation tenderness

For reasons unknown, temporomandibular disorder (TMD) can manifest as localized pain or in conjunction with widespread pain. We evaluated relationships between cytokines and TMD without or with widespread palpation tenderness (TMD-WPT or TMD+WPT, respectively) at protein, transcription factory activity, and gene levels. Additionally, we evaluated the relationship between cytokines and intermediate phenotypes characteristic of TMD and WPT. In a case-control study of 344 females, blood samples were analyzed for levels of 22 cytokines and activity of 48 transcription factors. Intermediate phenotypes were measured by quantitative sensory testing and questionnaires asking about pain, health, and psychological status. Single nucleotide polymorphisms (SNPs) coding cytokines and transcription factors were genotyped. TMD-WPT cases had elevated protein levels of proinflammatory cytokine monocyte chemotactic protein (MCP-1) and antiinflammatory cytokine interleukin (IL)-1ra, whereas TMD+WPT cases had elevated levels of proinflammatory cytokine IL-8. MCP-1, IL-1ra, and IL-8 were differentially associated with experimental pain, self-rated pain, self-rated health, and psychological phenotypes. TMD-WPT and TMD+WPT cases had inhibited transcription activity of the antiinflammatory cytokine transforming growth factor β1 (TGFβ1). Interactions were observed between TGFβ1 and IL-8 SNPs: an additional copy of the TGFβ1 rs2241719 minor T allele was associated with twice the odds of TMD+WPT among individuals homozygous for the IL-8 rs4073 major A allele, and half the odds of TMD+WPT among individuals heterozygous for rs4073. These results demonstrate how pro- and antiinflammatory cytokines contribute to the pathophysiology of TMD and WPT in genetically susceptible people. Furthermore, they identify MCP-1, IL-1ra, IL-8, and TGFβ1 as potential diagnostic markers and therapeutic targets for pain in patients with TMD.

Is self interdental cleaning associated with dental plaque levels, dental calculus, gingivitis and periodontal disease?

BACKGROUND AND OBJECTIVE

To ascertain whether interdental cleaning behaviours of Australian adults were associated with lower levels of plaque, gingivitis and periodontal disease.

MATERIAL AND METHODS

Data were obtained from the National Survey of Adult Oral Health 2004-06. Outcome variables were three indicators of oral hygiene outcomes (the presence or not of dental plaque, dental calculus and gingivitis) and two of periodontal disease (the presence or not of at least one tooth with a periodontal pocket or clinical attachment loss of ≥ 4 mm). The independent variable was classified into the following three groups: regularly clean interproximally 'at least daily' (daily+); 'less than daily' (< daily); and 'do not regularly clean interproximally' (reference group). Poisson regression with robust variance estimation was used to calculate prevalence ratios (PRs) and 95% confidence intervals (95% CIs) relative to the reference group, adjusted for covariates.

RESULTS

Regular self interdental cleaning was associated with less dental plaque (< daily, PR = 0.89, 95% CI = 0.84, 0.95; and daily+, PR = 0.89, 95% CI = 0.82, 0.96), less dental calculus (< daily, PR = 0.88, 95% CI = 0.80, 0.97; and daily+, PR = 0.79, 95% CI = 0.70, 0.89) and lower levels of moderate/severe gingivitis (daily+, PR = 0.85, 95% CI = 0.77, 0.94). Periodontal pocketing was less likely for the < daily group (PR = 0.61, 95% CI = 0.46, 0.82), but was not associated with daily+ cleaning (PR = 0.99, 95% CI = 0.663, 1.49). There was not a significant association between interdental cleaning and clinical attachment loss (< daily, PR = 0.90, 95% CI = 0.77, 1.05; and daily+, PR = 1.17, 95% CI = 0.95, 1.44).

CONCLUSION

Regular interdental cleaning was associated with better oral hygiene outcomes, such as dental plaque and gingivitis, although there was no significant association between regular interdental cleaning and clinical attachment loss.

The effect of a periodontal intervention on cardiovascular risk markers in Indigenous Australians with periodontal disease: the PerioCardio study

Background

Indigenous Australians experience an overwhelming burden of chronic disease, including cardiovascular diseases. Periodontal disease (inflammation of the tissues surrounding teeth) is also widespread, and may contribute to the risk of cardiovascular diseases via pathogenic inflammatory pathways. This study will assess measures of vascular health and inflammation in Indigenous Australian adults with periodontal disease, and determine if intensive periodontal therapy improves these measures over a 12 month follow-up. The aims of the study are: (i) to determine whether there is a dose response relationship between extent and severity of periodontal disease and measures of vascular health and inflammation among Indigenous Australian adults with moderate to severe periodontal disease; and (ii) to determine the effects of periodontal treatment on changes in measures of vascular health and inflammation in a cohort of Indigenous Australians.

Methods/Design

This study will be a randomised, controlled trial, with predominantly blinded assessment of outcome measures and blinded statistical analysis. All participants will receive the periodontal intervention benefits (with the intervention delayed 12 months in participants who are randomised to the control arm). Participants will be Indigenous adults aged ≥25 years from urban centres within the Top End of the Northern Territory, Australia. Participants assessed to have moderate or severe periodontal disease will be randomised to the study's intervention or control arm. The intervention involves intensive removal of subgingival and supragingival calculus and plaque biofilm by scaling and root-planing. Study visits at baseline, 3 and 12 months, will incorporate questionnaires, non-fasting blood and urine samples, body measurements, blood pressure, periodontal assessment and non-invasive measures of vascular health (pulse wave velocity and carotid intima-media thickness). Primary outcome measures are pulse wave velocity and carotid intima-media thickness.

Discussion

The study will assess the periodontal-cardiovascular disease relationship among Indigenous Australian adults with periodontal disease, and the effectiveness of an intervention aimed at improving periodontal and cardiovascular health. Efforts to understand and improve Indigenous oral health and cardiovascular risk may serve as an important means of reducing the gap between Indigenous and non-Indigenous health in Australia.

Trial Registration

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000817044

Dental visiting trajectory patterns and their antecedents

OBJECTIVE

This study aimed to test whether socioeconomic status (SES) in childhood may affect dental visiting patterns between ages 18 and 32 years.

METHODS

Using data from a complete birth cohort, childhood SES status was measured (using the New Zealand Elley-Irving index) at each study stage between birth and 15 years. Longitudinal dental visiting data were available for 833 study participants from ages 15, 18, 26, and 32, and these were analyzed by trajectory analysis.

RESULTS

Three separate dental visiting trajectories were identified; these were categorized as opportunists (13.1%), decliners (55.9%), and routine attenders (30.9%). Bivariate analyses showed low SES in childhood, male sex, and dental anxiety to be associated with membership of the "opportunist" dental visiting trajectory. Multinomial logistic regression showed that low childhood SES and dental anxiety were statistically significant predictors for membership in the opportunist or decliner trajectories after accounting for potential confounding variables.

CONCLUSION

Individuals who grew up experiencing low childhood SES were less likely to adopt a routine dental visiting trajectory in adulthood than those with a high childhood SES. Dental anxiety was also an important predictor of dental visiting patterns.

Effect of health promotion and fluoride varnish on dental caries among Australian Aboriginal children: results from a community-randomized controlled trial

Objectives

We tested a dental health program in remote Aboriginal communities of Australia's Northern Territory, hypothesizing that it would reduce dental caries in preschool children.

Methods

In this 2-year, prospective, cluster-randomized, concurrent controlled, open trial of the dental health program compared to no such program, 30 communities were allocated at random to intervention and control groups. All residents aged 18–47 months were invited to participate. Twice per year for 2 years in the 15 intervention communities, fluoride varnish was applied to children's teeth, water consumption and daily tooth cleaning with toothpaste were advocated, dental health was promoted in community settings, and primary health care workers were trained in preventive dental care. Data from dental examinations at baseline and after 2 years were used to compute net dental caries increment per child (d₃mfs). A multi-level statistical model compared d₃mfs between intervention and control groups with adjustment for the clustered randomization design; four other models used additional variables for adjustment.

Results

At baseline, 666 children were examined; 543 of them (82%) were re-examined 2 years later. The adjusted d₃mfs increment was significantly lower in the intervention group compared to the control group by an average of 3.0 surfaces per child (95% CI = 1.2, 4.9), a prevented fraction of 31%. Adjustment for additional variables yielded caries reductions ranging from 2.3 to 3.5 surfaces per child and prevented fractions of 24–36%.

Conclusions

These results corroborate findings from other studies where fluoride varnish was efficacious in preventing dental caries in young children.

Secondhand smoke and periodontal disease: atherosclerosis risk in communities study

OBJECTIVES

We investigated the relationship between secondhand smoke and periodontal disease in nonsmokers.

METHODS

We undertook a cross-sectional analysis of the Atherosclerosis Risk in Communities study with 2739 lifetime nonsmokers aged 53-74 years, unexposed to other sources of tobacco, who received a complete periodontal examination at visit 4. Exposure was reported as average hours per week in close contact with a smoker in the preceding year. We defined severe periodontitis as 5 or more periodontal sites with probing pocket depth of 5 millimeters or more and clinical attachment levels of 3 millimeters or more in those sites. Other outcomes were extent of periodontal probing depths of 4 millimeters or more and extent of clinical attachment levels of 3 millimeters or more.

RESULTS

In a binary logistic regression model, adjusted odds of severe periodontitis for those exposed to secondhand smoke 1 to 25 hours per week increased 29% (95% confidence interval = 1.0, 1.7); for those exposed to secondhand smoke 26 hours per week, the odds were twice as high (95% confidence interval = 1.2, 3.4) as for those who were unexposed.

CONCLUSIONS

Exposure to secondhand smoke and severe periodontitis among nonsmokers had a dose-dependent relationship.