|Year : 2020 | Volume
| Issue : 2 | Page : 86-93
Sociodemographic and clinical factors associated with poor oral health outcomes among United States adults
Apexa B Patel1, Dora Il'yasova2, Ashli Owen-Smith3
1 DDS Candidate at New York University College of Dentistry, MPH, BDS, School of Public Health, Atlanta, Georgia, USA
2 Ph.D., Associate Professor of Epidemiology, School of Public Health, Georgia State University, Atlanta, Georgia, USA
3 Ph.D. SM, Assistant Professor of Health Policy and Behavioral Sciences, School of Public Health, Georgia State University and Affiliate Investigator at Kaiser Permanente Georgia, Center for Research and Evaluation, Atlanta, Georgia, USA
|Date of Submission||26-Jan-2020|
|Date of Acceptance||12-Oct-2020|
|Date of Web Publication||16-Feb-2021|
Dr. Ashli Owen-Smith
School of Public Health, Georgia State University, Atlanta, Georgia, USA. Center for Research and Evaluation, Atlanta, Georgia
Source of Support: None, Conflict of Interest: None
Introduction: Oral health disparities remain a significant public health issue for United States (US) adults: 47.2% of US adults suffer from some form of periodontal diseases and 9% of US adults have advanced periodontal disease. Unfortunately, not much is known about the sociodemographic and clinical factors associated with these poor oral health outcomes. This study aims to examine the association between sociodemographic and clinical factors and poor oral health outcomes among US adults.
Materials and Methods: Data from the 2013 to 2014 National Health and Nutrition Examination Survey were used in the analysis for the participants aged 30 years and older (n = 4813). Logistic regression models were used to examine the association between sociodemographic and clinical factors and poor oral health outcomes. All analyses were conducted in SAS 9.4 and weighted to account for complex survey sampling methods.
Results: This study found that low socioeconomic status was negatively associated with periodontal diseases. Older age (ages 65 years and older), Hispanic and non-Hispanic black race/ethnicity and limited access to dental care were positively associated with periodontal diseases.
Conclusion: Future policy-level interventions are needed to address oral health disparities among vulnerable populations.
Keywords: Advanced periodontal disease, oral health, periodontal disease, severe periodontitis, sociodemographic and clinical factors
|How to cite this article:|
Patel AB, Il'yasova D, Owen-Smith A. Sociodemographic and clinical factors associated with poor oral health outcomes among United States adults. Int J Oral Health Sci 2020;10:86-93
|How to cite this URL:|
Patel AB, Il'yasova D, Owen-Smith A. Sociodemographic and clinical factors associated with poor oral health outcomes among United States adults. Int J Oral Health Sci [serial online] 2020 [cited 2021 Jun 15];10:86-93. Available from: https://www.ijohsjournal.org/text.asp?2020/10/2/86/309448
| Introduction|| |
Negative oral health conditions such as gingivitis (red, swollen gums) and periodontitis (damage to the soft tissue and bones supporting the teeth resulting in loose or loss of teeth) are common among adults and ultimately can lead to periodontal disease which is one of the biggest threats of poor oral health. Recent data from a Centers for Disease Control and Prevention (CDC) report on the epidemiology of periodontal disease suggest that approximately 47% of United States (US) adults aged 30 years and older suffer from some form of periodontal disease and 9% of US adults have advanced periodontal disease. Periodontal disease increases with age and around 70% of adults 65 years and older have periodontal disease in the US. Severe periodontitis is the 6th most prevalent disease globally affecting about 743 million people worldwide. Periodontal disease is the major cause for teeth loss in adults worldwide and contributes to edentulism and masticatory dysfunction which will affect their nutrition, quality of life and self-esteem and it has a huge impact on economic outcomes and health-care costs.
Oral health is important for overall nutrition and the control of different acute and chronic diseases. Improvement in oral health can reduce the risk of mastication and swallowing problems and nutritional deficiencies. Individuals who have mastication problems due to teeth loss or pain are more likely to eat soft, easily chewable food, and avoid well-balanced diet which may raise sugar and fat consumption levels, increasing their risk for other chronic diseases such as diabetes and cardiovascular diseases., Periodontal diseases account for 3.5 million years lived with disability and the loss of productivity from periodontal disease accounts for 442 billion worldwide and for severe periodontitis it accounts for 54 billion USD/year worldwide.
Various sociodemographic and clinical factors associated with poor oral health may help us to address oral health disparities related to periodontal diseases. Several research studies have documented poor oral health outcomes, specifically related to periodontal disease, vary by income, age, smoking status, diabetes status, access to dental care and race/ethnicity for the past decade. For example, in a study by Almerich-Silla et al., researchers found a significantly increased association between socioeconomic factors such as low socioeconomic status (SES), smoking, less primary education, male gender, older age, and poor oral health.
Evidence suggests that poor access to oral health care,, racial/ethnic minorities,, male gender, and lower SES, are associated with dental disease. The majority of the earlier studies documenting poor oral health outcomes specifically related to periodontal disease by sociodemographic and clinical factors were limited by several factors. First, some of these prior studies were conducted outside the US and many had relatively small sample sizes. Second, there was inconsistency in the ways in which periodontal disease was defined., For example, in the study by Eke et al., periodontal disease was defined if the participants had both clinical attachment loss and periodontal probing depth from six sites per tooth on all teeth, except the third molars, whereas in a study by Almerich-Silla et al., the researchers defined periodontal disease as per the Community periodontal index based on the WHO recommendations on six teeth (17/16, 11, 26/27, 36/37, 31, 46/47). Consequently, because of the inconsistency in defining the periodontal diseases in previous research studies, it is difficult to draw conclusions about the direction and strength of these associations. Finally, only a few earlier studies focused on US adults 30 years and older. For example, in the study by Almerich-Silla et al., the researchers conducted their study among adults who were 35–44 years of age. In another study Bloom et al., researchers focused on US adults 18–64 years of age. Only in the study by Eke et al., the researchers focused on US adults 30 years and older. Still, there is a further need to understand various sociodemographic and clinical factors that influence oral health among adults 30 years and older because the aging population is increasing in the US; thus, a better understanding of various sociodemographic and clinical factors that influence periodontal diseases will help us to reduce oral health disparities related to periodontal diseases and develop future interventions.,, Therefore, we aimed to further explore the association of various sociodemographic and clinical factors associated with poor oral health outcomes such as periodontal disease and advanced periodontal disease among US adults 30 years and older.
| Materials and Methods|| |
This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from the year 2013 to 2014. NHANES is an important component of the National Center for Health Statistics, which is part of the CDC., The NHANES survey collects data from a nationally representative sample of approximately 5000 people annually, located in different counties across the US. Each year fifteen counties are visited for the survey.,
NHANES is a unique program that combines both the interview component and physical examination component of the survey participants and is used to assess the health and nutritional status of the US population. The interview component of the survey consists of demographic, socioeconomic, dietary, and health-related questions and it is conducted at the participant's home by trained interviewers using the Computer-Assisted Personal Interview system. The physical examination component of the survey includes medical, dental, physiological measurements, and laboratory tests conducted by a team of highly trained medical professionals, including a physician, medical, and health technicians.
Variables of interest
Poor oral health outcomes
For poor oral health outcomes, this study used two variables from the NHANES 2013 to 2014 survey: Periodontal disease (gingivitis and periodontitis) and advanced periodontal disease (periodontitis). Study participants, who answered “yes” to the following question were coded as having periodontal disease: “Have you ever had treatment for gum disease such as scaling and root planning, sometimes called 'deep cleaning'?” Participants who answered “yes” to the following question were coded as having Advanced Periodontal Disease: “Have you ever been told by a dental professional that you have lost bone around your teeth?” Study participants who answered yes to the questions for both periodontal disease and advanced periodontal disease were coded as having “Periodontal disease plus advanced periodontal disease” which refers to the most severe form of periodontal disease (severe periodontitis).
The participants aged 30 years and older at the time of participation were included in this study; other participants were excluded as the poor oral health outcomes like periodontal diseases are more prevalent among the US adults 30 years and older and data for the outcome variables (periodontal disease and advanced periodontal disease) were not available for the participants who were younger than 30 years of age. Ages were recoded into three categories: (1) 30–44 years (2) 45–64 years (3) 65 years and older.
Individuals were grouped into males and females based on the self-reported responses at the time of screening for the survey.
Participants were categorized into four categories based on the self-reported responses of the participants during the survey: Hispanic, non-Hispanic black, non-Hispanic white, other race-including multi-racial.
Participants were categorized into four groups based on the self-reported responses: Married or living with a partner, widowed, divorced or separated, never married.
Participants were categorized into two groups based on the self-reported responses: US citizens and non-US citizens.
Participants were categorized into three groups (yes, no and borderline) based on the self-reported responses to the question, “Has your doctor told you that you have diabetes?'' Borderline diabetes was assessed by asking participants whether a doctor told them if they had prediabetes.
Participants were categorized into three groups based on the self-reported responses and these categories were chosen as they represented commonly used percentages of the poverty guidelines (i.e., 130% and 185% of the guidelines), by federal programs, in determining eligibility. The survey participants reported their family monthly income in dollar amounts and based on that index for the ratio of monthly income to poverty was calculated using the 2013 and 2014 Department of Health and Human Services' poverty guidelines. The index for the ratio of monthly income to poverty was then grouped into three categories such as ≤1.30, 1.30 <to ≤1.85, and >1.85. For this study, the SES was defined as follows: 1) Low SES for participants who were at monthly poverty level index ≤1.30, 2) Middle SES for participants who were at monthly poverty level index >1.30 to ≤1.85 and 3). High SES for participants who were at monthly poverty level index >1.85.
Participants were categorized into two groups based on the self-reported responses to the question about their history of recent tobacco use: Yes and No. The survey participants were asked the following question, “Used any tobacco product last 5 days?”
Limited access to dental care
Participants were categorized into two groups (yes or no) based on the self-reported responses to the question, “During the past 12 months was there a time when you needed dental care but could not get it at that time?”
For this study, all analyses from the NHANES 2013–2014 survey data were performed using SAS 9.4 (Statistical Analysis System, Cary, NC, USA). The survey data of NHANES 2013–2014 included selected 14,332 people who participated from thirty different survey locations. From these 14,332 persons, 10,175 persons completed the interview and 9813 persons completed the examination part of the survey. This study had a sample size of 4813 US adults 30 years and older after excluding the individuals who were younger than 30 years, and the participants who had missing data on the variables of interest.
For all 4813 participants, descriptive statistics were conducted for characteristics including age, gender, marital status, citizenship status, race/ethnicity, diabetes status, current smoking status and limited access to dental care. Logistic regression models were used to explore the association between sociodemographic and clinical factors and poor oral health outcomes. Regression analysis involved three regression models to explore the association between sociodemographic factors and poor oral health outcomes. The regression models were as follows: (1) periodontal disease, (2) advanced periodontal disease, and (3) combined periodontal disease and advanced periodontal disease.
Results of the logistic regression models were reported as odds ratios (ORs) and 95% confidence interval (CI). For all regression analysis, a two-sided P < 0.05 was considered statistically significant in this study.
| Results|| |
Characteristics of the study population
Of the total study population, 33.21% of respondents were age 30–44 years, 43.85% of respondents were age 45–64 years and 22.95% of participants were age 65 years and older. Approximately 52% were female. Most respondents (67.05%) were married or living with a partner, were US citizens (91.61%); had a middle SES (60.63%) and were non-Hispanic white (67.87%) race/ethnicity. At the time of the survey, 16.31% of participants had limited access to dental care; 20.30% of participants were current smokers and 12.18% respondents had diabetes. Out of the 4,813 survey participants, 21.34% (n = 1086) had periodontal disease, 12.17% (n = 620) had advanced periodontal disease and6.58% (n = 343) had both periodontal disease and advanced periodontal disease [Table 1].
The association between sociodemographic and clinical factors and poor oral health outcomes
Participants age 30–44 years had lower odds for advanced periodontal disease (OR = 0.40, 95% CI = 0.27–0.58) and combined periodontal disease and advanced periodontal disease (OR = 0.47, 95% CI = 0.29–0.75) compared to participants age 45–64 [Table 2]. Participants age 65 years and older had increased odds for advanced periodontal disease (OR 1.50, 95% CI 1.14–1.97) and combined periodontal disease and advanced periodontal disease (OR 1.59, 95% CI 1.06–2.39) compared to the participants age 45–64 [Table 2]. Participants from Hispanic race/ethnicity had increased association for periodontal disease (OR 1.85, 95% CI 1.40–2.44), and combined periodontal disease and advanced periodontal disease (OR 1.60, 95% CI 1.10–2.31) compared to participants from the non-Hispanic white race/ethnicity [Table 2]. Participants with lower SES had decreased odds of periodontal disease (OR 0.68, 95% CI 0.55–0.84), advanced periodontal disease (OR 0.77, 95% CI 0.59–0.99) and combined periodontal disease and advanced periodontal disease (OR 0.56, 95% CI 0.37–0.85) compared to the participants with higher SES [Table 2]. Current smokers had decreased odds for periodontal disease (OR 0.78, 95% CI 0.65–0.94) compared to participants who were not current smokers. Current smokers also had increased odds for advanced periodontal disease (OR 1.19, 95%CI 1.03–1.38) compared to participants who were not current smokers [Table 2]. Participants who had limited access to dental care had increased odds for advanced periodontal disease (OR 1.67, 95% CI 1.22–2.29) compared to participants who did not have limited access to dental care. There were no significant associations between gender, marital status, non-US citizenship, diabetes status and any of the negative oral health outcomes of interest.
|Table 2: Summary of regression analysis involving the sociodemographic and clinical factors|
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| Discussion|| |
The purpose of this study was to examine the associations between sociodemographic and clinical factors and poor oral health outcomes such as periodontal diseases among US adults 30 years and older. This study gives us a better understanding of the association of sociodemographic and clinical factors and poor oral health outcomes from recent NHANES Survey and it also confirms findings of the previous similar research studies. Furthermore, the findings of this study will be a useful baseline for comparison with future NHANES research studies to examine the associations between sociodemographic and clinical factors and periodontal diseases among US adults 30 years and older. Results from this study contribute to the evidence base that can be used to develop much-needed interventions for reducing oral health disparities involving periodontal diseases among US adults.
Overall, results from this study suggest that the survey participants aged 65 years and older had increased association for periodontal and advanced periodontal diseases and the study participants who were age 30–44 years had decreased association for periodontal diseases. The finding is consistent with the research study conducted by Mutamuliza et al. in which the researchers found deterioration of periodontal status with increasing age. Hispanic and non-Hispanic black participants had increased association for periodontal diseases which is similar to findings of the report by Eke et al. as Hispanic and non-Hispanic black adults face significant barriers in the utilization of dental services in the most states of the US. The survey participants who had limited access to dental care had increased association for advanced periodontal diseases, which supports the suggestions of the study by Fischer et al. in which the researchers stated that disproportionate poor oral health outcomes are prevalent among US adults due to poor access to dental care. Our study found that current smokers had decreased association for periodontal disease and increased association for the advanced periodontal disease compared to participants who were not current smokers. The earlier research study suggests that tobacco smoke and nicotine have the peripheral vasoconstrictive effect, which reduces oxygen and nutrient delivery to the gingival tissue. Furthermore, cigarette smoking causes functional impairment of both systemic and local components of the immune system, which have a role in the maintenance of periodontal health. In our study, conflicting finding for smokers regarding decreased association for periodontal disease and increased association for advanced periodontal disease could be due to the fact that for periodontal disease survey question was asking the participants if they had treatment for the gum disease and they might not have received the treatment for it even though they had the disease and so, they would have responded no as a response. In case of advanced periodontal disease survey question was asking the participants if they were being told by the health-care professional regarding having bone loss surrounding their teeth and hence, the advanced stage of periodontal disease.
Our results also suggest that low SES was negatively associated with periodontal diseases. This finding is similar to the results of the research study by Bertoldi et al., where the researchers found that an increase in SES corresponded to the worsening of the periodontal condition. These researchers hypothesized that this negative association may be because individuals from lower SES may prefer tooth extraction (as opposed to receiving preventative or interventional dental treatment); thus their teeth loss could explain the lower risk for periodontal diseases. Another possible explanation for this association in our study may be because survey participants of lower SES are often less likely to receive dental healthcare compared to individuals of higher SES and therefore may not have received a diagnosis of any oral health diseases in spite of the fact that they may still have had the condition.
This study is subject to limitations. First, this study used cross-sectional data from the NHANES 2013–2014 survey data and therefore, it is not possible to establish a causal relationship between sociodemographic and clinical factors and poor oral health outcomes. Second, oral health outcome data were based on self-report and therefore might be subject to information bias, recall bias, and social desirability bias. Information bias could influence responses of the survey participants as some of them may lack oral health literacy to understand some of the terminology used in the survey questions. The recall bias could have resulted due to recall error of remembering past events and it may result in underestimation of the association between various sociodemographic and clinical factors and periodontal diseases in this study. The social desirability bias could have resulted because the survey questionnaire used in the study involved some sensitive or private questions, which also may have led to underestimation of the association between various sociodemographic and clinical factors and periodontal diseases.
However, this research study had several strengths worth noting including that: (1) this study was based on a nationally representative sample, (2) the NHANES survey includes rigorous data collection with reliable instruments, and (3) the information for the poor oral health outcomes was collected by interviews by highly trained health professionals.
| Implications of Findings, Recommendations, and Conclusions|| |
This study found that participants aged 30–44 years and participants from low SES had decreased association for advanced periodontal diseases while participants aged 65 years and older, who were current smokers, who had limited access to dental care had increased association for advanced periodontal diseases. Participants from Hispanic and non-Hispanic black race/ethnicity had increased association for periodontal diseases. Furthermore, participants from low SES and current smokers had decreased association for periodontal diseases. However, there is a need for conducting longitudinal studies for further assessing the association between and mechanisms by which sociodemographic and clinical factors impact poor oral health outcomes.
Our study findings suggested that limited access to dental care is positively associated with periodontal disease which underscores that cost and affordability are important issues for oral health-care access. Policies are needed that address the cost of oral healthcare; for example, making oral health-care affordable for all the people by expanding the oral health-care insurance coverage. US adults on Medicaid, for example, often face barriers in finding a dentist who will accept Medicaid insurance and treat their dental problems. We should direct our efforts in expanding oral health delivery services, improving Medicaid reimbursement, and promoting oral health education.
Furthermore, oral health interventions require support from federal and state governments to implement new social policies and allocate funds appropriately so that we can reduce oral health disparities. There is a need to organize and prioritize interventions to people at all socioeconomic levels, with a particular focus to address the special needs of low-resourced individuals who face obstacles and barriers in accessing oral healthcare and interventions. We should also integrate oral healthcare and primary care and implement oral health prevention in primary health-care settings. We should give basic training to the primary health-care professionals by incorporating the oral health core clinical training in their health-care professional training and education. Providing training to primary health-care professionals would help them in the identification of common oral diseases and providing timely referrals to the dentist, dental health care professionals or specialists. It will also help in improving provider-to-provider communication, and more importantly, the oral health of vulnerable populations of the US. We should implement a standard set of oral health clinical competencies for primary healthcare professionals and modification in payment policies should be done so that we can efficiently address costs of implementing oral health competencies and provide incentives to health care systems and professionals.,,,,
Finally, we should make efforts to develop strategies to improve behavioral, lifestyle, and community-level social changes as that will help us to prevent poor oral health outcomes. The oral health interventions and policy efforts must be directed toward including a “fundamental-social-cause approach” (which includes resources such as knowledge, money, power, prestige, and social connections that will help us to avoid risks related to morbidity and mortality) that will benefit all the individuals, regardless of their socio-economic status, resources, or behaviors. We should focus on taking state and community-based approaches in addition to the national surveys for oral health research and surveillance so that we can identify cost-effective solutions for the prevention and treatment of oral health diseases. Furthermore, we need to monitor the impacts of the oral healthcare reform in the US adults continuously so we can identify additional barriers and develop effective solutions to reduce oral health disparities.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Gil-Montoya JA, de Mello AL, Barrios R, Gonzalez-Moles MA, Bravo M. Oral health in the elderly patient and its impact on general well-being: a nonsystematic review. Clin Interv Aging 2015;10:461-7.
Tonetti MS, Jepsen S, Jin L, Otomo-Corgel J. Impact of the global burden of periodontal diseases on health, nutrition and wellbeing of mankind: A call for global action. J Clin Periodontol 2017;44:456-62.
Almerich-Silla JM, Alminana-Pastor PJ, Boronat-Catala M, Bellot-Arcis C, Montiel-Company JM. Socioeconomic factors and severity of periodontal disease in adults (35-44 years). A cross sectional study. J ClinExp Dent 2017;9:e988-94.
Patrick DL, Lee RS, Nucci M, Grembowski D, Jolles CZ, Milgrom P. Reducing oral health disparities: A focus on social and cultural determinants. BMC Oral Health 2006;6 Suppl 1:S4.
Fischer DJ, O'Hayre M, Kusiak JW, Somerman MJ, Hill CV. Oral health disparities: A perspective from the National Institute of Dental and Craniofacial Research. Am J Public Health 2017;107(S1): S36-8.
Huang DL, Park M. Socioeconomic and racial/ethnic oral health disparities among US older adults: Oral health quality of life and dentition. J Public Health Dent 2015;75: 85-92.
Malecki K, Wisk LE, Walsh M, McWilliams C, Eggers S, Olson M. Oral health equity and unmet dental care needs in a population-based sample: Findings from the Survey of the Health of Wisconsin. Am J Public Health 2015;105 Suppl 3:S466-74.
Eke PI, Dye, BA, Wei L, Slade GD, Thornton-Evans GO, Borgnakke WS, et al
. Update on prevalence of periodontitis in adults in the United States: NHANES 2009-2012. J Periodontol 2015;86:611-22.
Mutamuliza J, Rwema F, Rulisa S, Ntaganira J. Prevalence and associated risk factors of periodontal disease among adults attending dental department in Rwanda Military Hospital (Rwanda): A cross sectional study. Dent Open J 2015;2:105111.
Zhang Q, Li Z, Wang C, Shen T, Yang Y, Chotivichien S, Wang L. Prevalence and predictors for periodontitis among adults in China, 2010. Glob Health Action. 2014 Jul 8;7:24503. doi: 10.3402/gha.v7.24503. PMID: 25008055; PMCID: PMC4090366.
-Bloom B, Simile CM, Adams PF, Cohen RA. Oral health status and access to oral health care for U.S. adults aged 18-64: National Health Interview Survey, 2008. Vital Health Stat 10. 2012 Jul;253:1-22. PMID: 23077776.
Borrell LN, Beck JD, Heiss G. Socioeconomic disadvantage and periodontal disease: The Dental Atherosclerosis Risk in Communities study. Am J Public Health 2006;96:332-9.
Tomar SL, Asma S. Smoking-attributable periodontitis in the United States: Findings from NHANES III. J Periodontol 2000;71:743-51.
Sun KT, Chen SC, Lin CL, Hsu JT, Chen IA, Wu IT, Palanisamy K, Shen TC, Li CY. The association between Type 1 diabetes mellitus and periodontal diseases. J Formos Med Assoc. 2019 Jun;118:1047-1054. doi: 10.1016/j.jfma.2018.10.012. Epub 2018 Nov 1. PMID: 30391109.
Preshaw PM, Alba AL, Herrera D, Jepsen S, Konstantinidis A, Makrilakis K, et al.
Periodontitis and diabetes: A two-way relationship. Diabetologia 2012;55:21-31.
Silvestre FJ, Miralles L, Llambes F, Bautista D, Solá-Izquierdo E, Hernández-Mijares A. Type 1 diabetes mellitus and periodontal disease: relationship to different clinical variables. Med Oral Patol Oral Cir Bucal 2009;14:E175-9.
Myllymäki V, Saxlin T, Knuuttila M, Rajala U, Keinänen-Kiukaanniemi S, Anttila S, Ylöstalo P. Association between periodontal condition and the development of type 2 diabetes mellitus-Results from a 15-year follow-up study. J Clin Periodontol. 2018 Nov;45:1276-1286. doi: 10.1111/jcpe.13005. Epub 2018 Oct 21. PMID: 30133880.
Kaur G, Holtfreter B, Rathmann W, Schwahn C, Wallaschofski H, Schipf S, et al
. Association between type 1 and type 2 diabetes with periodontal disease and tooth loss. J Clin Periodontol 2009;36:765-74.
Edelstein BL. Disparities in oral health and access to care: findings of national surveys. Ambul Pediatr 2002;2:141-7.
Simangwa LD, Åstrøm AN, Johansson A, Minja IK, Johansson AK. Oral diseases and sociodemographic factors in adolescents living in Maasai population areas of Tanzania: A cross-sectional study. BMC Oral Health 2018;18:200. doi: 10.1186/s12903-018-0664-6.
Atchison KA, Rozier RG, Weintraub JA. Integration of oral health and primary care: Communication, coordination, and referral. Washington, DC: NAM Perspectives. Discussion Paper, National Academy of Medicine; 2018. [doi. org/10.31478/201810e].
Bertoldi C, Lalla M, Pradelli JM, Cortellini P, Lucchi A, Zaffe D. Risk factors and socioeconomic condition effects on periodontal and dental health: A pilot study among adults over fifty years of age. Eur J Dent 2013;7:336-46. [Full text]
[Table 1], [Table 2]