Dental treatment needs in the Canadian population: analysis of a nationwide cross-sectional survey

Prior to the 2007/09 Canadian Health Measures Survey (CHMS), there was no nationally representative clinical data on the oral health needs of Canadians since the 1970/72 Nutrition Canada National Survey[1]. This is of concern as identifying the needs of a population is the primary step in the development and planning of programs[2]. In Canada, dental services are predominantly delivered in the private sector on a fee-for-service basis. Canadians are largely responsible for financing their own dental care, so enabling resources for obtaining care, such as income and insurance, dictate the use of dental services instead of the need for treatment. In this regard, it is especially important to identify the subgroups that have the greatest amount of unmet needs, in order to determine priorities for the most effective use of public resources. Without a clear picture of the burden of oral disease and how it is distributed, the danger of a top-down approach to providing health services arises, which relies heavily on what a few people perceive to be the needs of the population rather than what they actually are[3]. In short, this information is important as it can help policymakers understand the distribution of population needs, allowing them to compare current approaches to dental care with actual treatment needs.

Previous Canadian studies examining treatment needs have primarily focused on children and the elderly[4‐6]. Generally, the oral health status of at risk children and adolescents appears to be poor resulting in the need for several treatments including urgent, restorative, periodontal and preventive care[4‐6]. Similarly, very high levels of unmet need among older adults have been observed regardless of whether they live in an institution or are homebound[7]. The treatments they require have been reported as consisting of urgent, preventive, periodontal, restorative and prosthodontic care[7]. Other studies of need have also relied on self-reported information. Although patient self-reports are the most convenient mechanism for obtaining first-hand health information, they have been found to be heavily influenced by personal beliefs, cultural background, and social, educational, and environmental factors[8]. Furthermore, regarding treatment needs, self-reports have been found to often provide different assessments from those of clinically determined standards[8]. For example, it has been found that people are usually unable to report signs and symptoms related to periodontal conditions[8, 9].

This paper outlines the normative dental treatment needs of the Canadian population. It examines if any characteristics are predictive of having unmet dental treatment needs, and the type of treatment needed. It applies a modified version of Andersen’s emerging model of health services utilization to determine which factors are the strongest predictors of having an unmet dental treatment needs. The goal is to inform policymakers of the levels and distribution of treatment needs in the Canadian population.

The final sample included 5,586 participants, representing 29,157,460 Canadians when weighted, out of a current population of 33,476,688[13]. Table3 shows that the sample consisted of an approximately even number of males (49.9%) and females (50.1%), the majority of the participants were 20 to 39 (30.9%) and 40 to 59 (33.5%) years of age, and slightly over half had never smoked (52.6%). Roughly an equal proportion of the population had a degree or diploma (49.6%), the majority was born in Canada (79.0%) and were non-Aboriginal (96.9%). Most were in the highest income category (47.9%) and had private dental insurance coverage (62.3%). The majority reported their oral health and general health as excellent to good (respectively, 84.5% and 91.9%), rarely or never experienced oral pain (88.4%), and most did not perceive a need for dental treatment (67.0%). The majority said that they had visited the dentist in the last year (74.5%), and that they had not avoided recommended dental treatment in the past year due to cost (83.5%).

Most of the sample had no treatment needs (65.8%). Of the 34.2% who did require treatment, 19.4% were found to have one dental treatment need and 14.6% required more than one need, representing close to 5 million people. Looking into the types of dental treatments needed, Figure2 displays that most needed restorative (20.4%) and preventive (13.7%) care. Approximately 6.0%, representing nearly 2 million people, had an urgent need (i.e. treatment was required within one week).

As displayed in Table4, all of the variables, with the exception of immigrant status, were significant predictors of having an unmet dental treatment need. Those reporting their oral health as fair or poor were 5.9 times more likely to have an unmet need than those reporting excellent or good oral health (95% CI=4.3-8.0, P=0.001). Those who perceived a need for treatment were 4.6 times more likely to have a treatment need than those who did not (95% CI=3.7-5.8, P=0.001).

According to Table4, those who reported poor oral health, a perceived need for treatment, and had poor dental visiting habits, were found to have the highest odds of requiring dental treatment. This finding was also present for each treatment type (data not shown). Table5 shows that those reporting their oral health as fair or poor, and those that perceived a need for dental treatment, were 4.6 (95% CI=3.7-5.7, P=0.001) and 4.5 (95% CI=3.4-6.1, P=0.001) times more likely than their counterparts, respectively, to require restorative treatment, the most prevalent needed treatment found in the sample. Also, those who saw a dental professional more than one year ago (OR=3.0, 95% CI=2.3-3.8, P=0.001) and tended to visit the dentist less than once a year or only for emergencies or never (OR=3.0, 95% CI=2.3-3.8, P=0.001), were both more likely than their counterparts to need restorative care.

Finally, to determine the strongest predictors of dental treatment need, five models were used to progressively adjust for the factors in the modified Andersen model (predisposing, enabling, need, personal dental health practice and use of dental service factors). Table6 shows the results obtained from the last and final model (Model 5), which entered all of the factors. After adjustment, being male, a current smoker, having less than a degree or diploma, having public insurance coverage, never flossing, and reporting a last dental visit of more than one year ago, were significant predictors of having an unmet dental treatment need. The strongest predictors were need variables. Those who reported their oral health as fair or poor and had a self-perceived need for treatment were nearly three (OR=2.9, 95% CI=1.8-4.6, P=0.001) and three-and-a-half (OR=3.4, 95% CI=2.3-4.9, P=0.001) times more likely to have an unmet need.

This study is the first in approximately 40 years to explore representative clinical information on the dental treatment needs of Canadians. Its findings suggest that policymakers should be concerned that an estimated 12 million Canadians had an unmet dental treatment need, that close to 5 million had numerous unmet needs, and that nearly 2 million had an urgent need (i.e. treatment was required within one week). With most people requiring restorative and preventive care, these findings reflect those of Quiñonez and Locker (2007)[14], who found that 26% of the Canadian adult population self-reported having a cost-prohibitive (i.e. unmet) dental need, with fillings and preventive procedures (cleanings and check-ups) being the most prevalent unaffordable needs.

Poor self-rated oral health, a perceived need for dental treatment, and infrequently visiting a dental professional were the main predictors of having unmet dental treatment needs. This seems counterintuitive since one would expect that those who are conscious of their poor oral health and requirement for treatment would visit the dentist in order to meet their needs. However, here we see the ‘paradox of need’, as noted by Muirhead et al. (2009)[15], who found that working poor Canadians who reported the worst oral health or who had a perceived need for treatment, were the lowest dental service users. Studies have shown that people with poor oral health and a perceived need for treatment may avoid dental visits because of the barriers imposed by the costs of dental treatment, the anxiety of potential pain, or concern about being judged by dentists for their poor oral condition[15, 16]. Unfortunately, aside from avoiding dental treatment for cost reasons, which was found to be the case for around 17% of the sample population, the CHMS did not collect information regarding any other potential reasons for not visiting the dentist (e.g. anxiety, fear of judgement, etc.).

This study also found that those who had access to public programs were worse off in terms of having unmet dental needs, when compared to those with private insurance or without any insurance coverage. The National Survey of Adult Oral health 2004–06 conducted in Australia found something similar, noting that untreated decay was more frequent among those eligible for public dental care[17]. These findings support a key issue noted by Leake and Birch (2008)[18], who stated that although the public funding of dental care provides a means of overcoming the divergence between the ability to pay for care and need for care, having such coverage is not enough. There are other factors at play other than just affordability, such as the availability, accommodation, and acceptability of dental care. For example, as noted by Quiñonez et al., (2010)[19], Canadian dentists have consistently voiced their dissatisfaction with public insurance plans, and approximately a third have reported limiting the number of patients they accept who have public insurance. Therefore, solely increasing public subsidies for these groups may not fully increase their utilization of dental services unless other access issues are also addressed.

It is important to consider the limitations of this study. Firstly, it is difficult to know the true extent of treatment need in the Canadian population considering the specific details of need were not collected by the CHMS. For example, multiple treatment needs of the same type were recorded as a single need (e.g. a participant that required a single restoration was reported similarly to a participant with three restorations). Also, this study cannot support conclusions about the causal effects of any predisposing, enabling, need, personal dental health, and use of dental service factors, since it is based on a cross-sectional survey. Grouping children and adults together in the analysis is recognized as a limitation, as there are potential differences in treatment needs. The variable used for last dental visit was dichotomized into two categories, and the cut-off point of visited “in the last year” is noted to be a limitation of the study. Information on those who visit the dentist once every two, three years, etc., could have been explored to observe whether there would be changes in the severity of treatment need. Lastly, it is important to recall that certain populations who are known to have high levels of dental disease and limited access to dental care (e.g. Aboriginal populations and seniors in institutions) were not included in the CHMS. Therefore, the 34% of the population found to require dental treatment is most likely an underestimation of the true need present in the Canadian population.

This study highlights the importance of an ongoing surveillance system to measure the oral health status of populations, oral health inequalities, and other trends. Internationally, it still remains a challenge for most countries to establish a database for the clinical monitoring and surveillance of oral health[20]. In order to predict the future burden of oral disease, as well to identify potential interventions to reduce the burden of these diseases, data collection and reporting standards are needed to ensure that data is consistently collected and used effectively to inform policy, prevention and control activities for health[20]. Without this information, the capacity to develop oral health policy based on evidence is limited. Therefore, the WHO recommends that regular clinical oral health surveys be conducted every 5–6 years in the same community or setting[20]. In this regard, the current study provides valuable baseline information on the dental treatment needs of most Canadians, and highlights the greatest areas of unmet need. This knowledge can now be used by program and policymakers to develop or refine targeted dental health programs in an effort to improve the oral health of the Canadian population as a whole.