Oral microbiome research from a public health perspective and implications for oral health.

Advancing oral microbiome research has revealed the association between oral microbiome composition and oral disease. However, much of the research has predominantly focused on comparing health and disease conditions, overlooking the potential dental public health implications. This article examines the evolution of oral microbial research from inception, advancement, and current knowledge of health-associated microbiota. Specifically, we focus on two key aspects: the impact of lifestyle and environmental factors on the oral microbiome and using the oral microbes as a therapeutic modality. The complex interaction of host intrinsic, environmental, and lifestyle factors affects the occurrence and development of the oral microbiota. The article highlights the need for ongoing research that embraces population diversity to promote health equity in oral health research and integrate public health practices into microbiome-based research. The implication of population-level interventions and targeted approaches harnessing the oral microbiome as an intervention, such as oral microbiome transplantation, should be further explored.

Access to dental care barriers and poor clinical oral health in Australian regional populations.

BACKGROUND: This paper investigated the associations between oral health with behavioural, demographic, periodontitis risk, financial and access to dental care barriers and compared the results in three Australian regional areas. METHODS: Data were obtained from the Australian National Study of Adult Oral Health (2017-18). Oral health status was measured using DMFT-score, and mean numbers of decayed, missing or filled teeth and periodontitis prevalence using the Center for Disease Control and Prevention (CDC) and the American Academy of Periodontology (AAP) Periodontal Classification. The analysis included these dependent variables by three regional areas, seven socio-demographic variables, two periodontal disease risk factors, two preventive dental behaviours, two barriers to dental care and three access to dental care variables. RESULTS: Of the 15,731 people interviewed, 5,022 were examined. There was no significant difference in periodontitis prevalence between the regions. All the socio-demographic characteristics, periodontal disease risk factors and preventive dental behaviours were significantly associated with at least one of the dental caries indicators. In multivariable analysis, there was no significant association between regional location with any of the four clinical dental caries variables. CONCLUSION: Poorer oral health outside major cities was associated with household income, education level, higher smoking, usual reason for and frequency of dental visiting.

Oral health changes among Indigenous and non-Indigenous Australians: findings from two national oral health surveys.

BACKGROUND: Historically, Indigenous Australians experienced poorer oral health than non-Indigenous Australians. We aimed to ascertain if Indigenous Australian oral health improved relative to non-Indigenous oral health between the 2004-06 and 2017-18 National Surveys of Adult Oral Health (NSAOH). METHODS: Both NSAOHs were population-based cross-sectional surveys of Australian adults aged 15 years or more. In both surveys, representative samples of adults were drawn through a three-stage, stratified sample design within metropolitan and regional areas in each state/territory. Frequencies of Indigenous and non-Indigenous self-reported and clinical oral health variables were ascertained, and differences were calculated between the 2004-06 and 2017-18 NSAOHs. Ninety-five per cent confidence intervals were calculated and weights were used to account for the complex sampling methodology of both surveys. RESULTS: In 2004-06, 229 Indigenous and 13 882 non-Indigenous Australians provided self-report data, and 87 and 5418 of these had dental examinations, respectively. In 2017-18, 334 Indigenous and 15 392 non-Indigenous Australians provided self-report data, and 84 and 4937 of them had dental examinations respectively. Between the surveys, relative to their non-Indigenous counterparts, Indigenous Australians experienced greater levels of: inadequate dentition (4.2%), experience of toothache (4.8%), problem-based dental attendance (4.5%) and 1+ teeth decayed, missing or filled (4.4%). CONCLUSIONS: The gap between poor self-reported and clinical oral health between Indigenous and non-Indigenous Australians was greater in the more recent survey.

Salivary characteristics and dental caries experience in remote Indigenous children in Australia: a cross-sectional study.

BACKGROUND: While associations between salivary characteristics and dental caries have been well studied, we are not aware of this being assessed in a remote Indigenous child population, where lifestyles may be different from urban children. Our aim was to assess associations between caries experience and putative biomarkers in saliva, accounting for oral hygiene and dietary habits. METHODS: Children attending schools in an Indigenous community in remote north Queensland, Australia were invited to an oral examination by qualified and calibrated examiners. Salivary flow rate, pH, buffering capacity and loads of mutans streptococci (MS), lactobacilli (LB) and yeasts were determined. Also, data on tooth brushing frequency and soft drinks consumption were obtained via a questionnaire. Caries experience was recorded by the International Caries Detection and Assessment System (ICDAS-II), and quantified as decayed, missing and filled surfaces. Relationships between the salivary variables and the cumulative caries experience (dmfs+DMFS) in the deciduous and permanent dentitions were examined by multivariate analyses to control the effect of confounders. RESULTS: The mean cumulative decayed (DS + ds), missing (MS + ms) and filled (FS + fs) surfaces were 3.64 (SD: 4.97), 1.08 (4.38) and 0.79 (1.84) respectively. Higher salivary MS and LB counts, low tooth brushing frequency and daily soft drink consumption were significantly related to greater caries experience. Caries experience was about twice in those with ≥10^5 CFU/ml saliva counts of MS (mean = 6.33, SD: 8.40 vs 3.11, 5.77) and LB (7.03, 7.49 vs 4.41, 8.00). In the fully-adjusted multivariate model, caries experience in those with higher counts of MS and LB were 51 and 52% more than those with lower counts. CONCLUSIONS: As with studies in other populations, childhood salivary counts of MS and LB were significantly associated with greater caries experience in this remote Indigenous community. To address the serious burden of oral disease, we are researching ways to promote a healthy oral environment by encouraging good dietary habits, and emphasising the importance of daily tooth brushing with a fluoridated toothpaste. Our ongoing longitudinal studies will indicate the success of measures employed to reduce the counts of bacteria closely associated with cariogenesis and their impact on caries increment. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ( ANZCTR ), No: ACTRN12615000693527; date of registration: 3rd July 2015.

Periodontal therapy and glycaemic control among individuals with type 2 diabetes: reflections from the PerioCardio study.

OBJECTIVES: Diabetes mellitus and periodontal disease are highly prevalent among Indigenous Australian adults. Untreated periodontitis impacts glycaemic control in people with diabetes. The aim of this study was to report on the effect of periodontal therapy on glycaemic control among people with obesity. METHODS: This subgroup analysis is limited to 62 participants with diabetes from the original 273 Aboriginal Australian adults enrolled into the PerioCardio study. Intervention participants received full-mouth non-surgical periodontal scaling during a single, untimed session while controls were untreated. Endpoints of interest included change in glycated haemoglobin (HbA1c), C-reactive protein (CRP) and periodontal status at 3 months post-intervention. RESULTS: There were more females randomized to the treatment group (n = 17) than control (n = 10) while the control group had a higher overall body mass index (BMI) [mean (SD)] 33.1 (9.7 kg m-2 ) versus 29.9 (6.0 kg m-2 ). A greater proportion of males were followed up at 3 months compared to females, P = 0.05. Periodontal therapy did not significantly reduce HbA1c: ancova difference in means 0.22 mmol mol-1 (95% CI -6.25 to 6.69), CRP: ancova difference in means 0.64 (95% CI -1.08, 2.37) or periodontal status at 3 months. CONCLUSIONS: Non-surgical periodontal therapy did not significantly reduce glycated haemoglobin in participants with type 2 diabetes. Reasons are likely to be multifactorial and may be influenced by persistent periodontal inflammation at the follow-up appointments. Alternatively, the BMI of study participants may impact glycaemic control via alternative mechanisms involving the interplay between inflammation and adiposity meaning HbA1c may not be amenable to periodontal therapy in these individuals.

Associations with dental caries experience among a convenience sample of Aboriginal Australian adults.

BACKGROUND: Few studies have examined dental caries experience in Aboriginal adults. The objectives of this study were to describe the dental caries experience of some Aboriginal Australian adults residing in the Northern Territory, and to determine associations with dental caries experience. METHODS: A convenience sample of Aboriginal adults from Australia's Northern Territory was dentally examined. Self-reported oral health information was collected through a questionnaire. RESULTS: Data were available for 312 participants. The per cent of untreated decayed teeth (per cent DT >0) was 77.9 (95% CI 73.0 to 82.1), the mean DT was 3.0 (95% CI 2.6 to 3.4), the prevalence of any caries experience (the per cent DMFT >0) was 95.5 (95% CI 92.6 to 97.3) and the mean DMFT was 9.7 (95% CI 8.9 to 10.5). In multivariable analyses, unemployment and not brushing teeth the previous day were associated with the per cent DT >0. Problem-based dental attendance was associated with both the mean DT and the per cent DMFT >0. Older age, residing in the capital city, being non-incarcerated, last visiting a dentist <1 year ago and problem-based dental attendance were associated with the mean DMFT. CONCLUSIONS: Dental caries experience among this convenience sample of Aboriginal Australian adults was very high. Most factors associated with dental caries were social determinants or dental service access-related.

Oral health behaviours and perceptions reported by Indigenous Australians living in Darwin, Northern Territory.

OBJECTIVE: To describe the reported oral health behaviours and perceptions of Indigenous Australians living in Darwin, Northern Territory and to compare those with estimates for Darwin and Australia derived from the National Survey of Adult Oral Health (NSAOH). PARTICIPANTS: A total of 181 Indigenous Australians aged 22 years and over living in Darwin, participating in screening for a wider randomised clinical trial, were included. METHOD: Information on socio-demographic characteristics, oral health status including oral health behaviours and perceptions was collected using a questionnaire. Differences between the Darwin study (DS) participants and Australians in NSAOH were made based on non-overlapping 95% confidence intervals. RESULTS: Almost 72% of DS participants had last seen a dentist over a year earlier, compared to 47% and 39% of NSAOH Darwin and Australian participants, respectively. A higher proportion of DS participants usually visited a dentist because of a problem than NSAOH Darwin and NSAOH Australian participants. A higher proportion of DS participants had avoided or delayed a dental visit because of cost than NSAOH participants. Over three times as many DS participants rated their oral health as fair/poor compared to NSAOH participants. A higher proportion of DS participants had perceived gum disease and one or more symptoms of gum disease than NSAOH participants. A higher proportion of DS participants experienced toothache, felt uncomfortable about appearance of their mouth and avoided eating because of oral problems than NSAOH participants. CONCLUSIONS: A higher proportion of Indigenous Australians living in Darwin presented with non-optimal oral health behaviours and perceptions compared with both the Darwin and Australian general populations.

Periodontal disease and dental caries among Indigenous Australians living in the Northern Territory, Australia.

BACKGROUND: The aim of this study was to describe the caries experience and severity of periodontal disease in a convenience sample of Indigenous Australians living in the Northern Territory. METHODS: Data were gathered via self-reported questionnaire and dental examination by calibrated examiners. Socio-demographic characteristics were compared with data from the 2011 Australian census while prevalence of periodontal disease and dental caries was compared against weighted estimates from the National Survey of Adult Oral Health 2004-2006. In each comparison, non-overlapping 95% confidence intervals inferred a significant difference. Within-study comparisons were assessed via chi-square, t-tests and analysis of variance for differences among study participants. RESULTS: A total of 312 Indigenous Australian participants provided completed data (average age 39.5 ± 10.5 years, 174 males). Of these, 87.5% were confirmed periodontitis cases; 3.5 times that of national-level estimates. The experience of untreated caries was five times that of national estimates (mean decayed 3.0 versus 0.6). Periodontitis case status was positively associated with older age, male gender and presence of diabetes. CONCLUSIONS: Periodontal disease and untreated caries were significantly more prevalent in this sample of Indigenous Australians compared to the general Australian population. The prevalence of periodontal disease was markedly higher than that previously described for Indigenous Australians.