Among the many health care issues that middle-aged and older adults face, care of one’s teeth is one that may have serious repercussions if overlooked. Neglect of oral care may lead to tooth decay, pain, tooth loss, and inflammation. More importantly, untreated or delayed treatment of oral diseases affects nutritional status, causes oral pain and discomfort, and ultimately affects individuals’ quality of life (1). Over the past several decades, dental care utilization has risen considerably (2, 3). Specifically, national surveys have reported that the proportion of respondents who had seen a dentist in the past year rose from an estimated 53.9 in 1983 to 75.5 in 1997, for adults 25 and older, with women reporting higher rates than men throughout the study period (3). In the past, rates of dental care use also differed across racial/ethnic groups. Whites reported consistently higher rates than Blacks and Hispanics, with Hispanics usually falling somewhere between the White and Black rates (2, 3). Based on data from three large national surveys, the proportions of Whites seeking dental care increased from 46.89 to 47.84%, while the proportion of Blacks increased from 23.44 to 26.73%. The proportion for Hispanics stayed approximately the same over the time period (29.86% in 1996). This study also found an increase in the proportion of individuals over the age of 65 that had seen a dentist in the past year between 1977 and 1996 (29.88–41.33%) (2). While prior reports presented findings regarding utilization rates of individuals in earlier time periods; no up-to-date statistics on whether rates of utilization meet the annual dental checkups recommended by the US Department of Health and Human Services (4). Further, most of these prior studies only reported cursory descriptive results, and have not included formal statistical tests by adjusting for population heterogeneity that could potentially contribute to the impact of race/ethnicity on dental care utilization.

Limited research is available on dental care utilization among American Indians/Alaskan Natives; however, the available research on this group has focused on the lack of access American Indians have to health care. Many American Indians suffer from a lack of access to dental care as a result of under-staffed medical centers, excessive estimated wait times at medical centers, and/or distances that are too long to travel for such medical services (5). Such factors clearly have a negative impact on American Indians opportunity and propensity to utilize dental care.

Similarly, few studies are available on dental care use among middle age and older Asian Americans in nationally representative samples. Using the National Health Interview Survey (NHIS) (1997–2000) data, one descriptive study reported that 58% of the Asians aged 65 and above had visited a dentist in the previous year, slightly higher than the rate in Whites (56.6%); while the rate for Asians aged 45–64 was 66.1%, slightly lower than their white counterparts (67.6%) (6). While the NHIS study was administered in English to the Asian participants, using a convenient sample, another study conducted among Chinese American elders in their native language found that only 47% of the participants aged 60 and above reported having a dental visit within the previous year (7).

These prior studies examined changes in dental care use in regard to certain racial/ethnic groups, primarily Whites, Blacks, and Hispanics, with the majority excluding groups such as Asians and American Indians/Alaskan Natives. While many of these studies looked at a range of age groups, few targeted adults over age 50. Those studies that included individuals over age 50 presented results with the aim of contrasting with other age groups (2, 8). The number of middle-aged and older adults has increased significantly for the past several decades (9) and has become increasingly diverse (10). Studies have shown that there is an increasing number of middle-aged and older adults who are retaining their natural teeth (11–13). These findings highlight the importance of dental care use for this segment of the population.

This study is unique in that it studies dental care use among Asian and Native Americans in comparison with other major racial/ethnic groups using a nationally representative survey. Overall, Asian Americans may have a higher use of preventive dental care than other minority populations in the U.S. On the other hand, American Indians have less access to dental care which would affect their use of preventive care. However, no studies have empirically examined the dental care utilization among Asian and Native Americans using a national representative survey. It is unknown whether the use of dental care would be explained by other confounding factors for these population segments.

To guide the analysis, this study offers the following hypotheses.

First, preventive dental care use among middle-aged and older Americans increased between 1999 and 2008 (H₁) (2, 3).

Second, significant race/ethnic differences exist in the trend of preventive dental care utilization. In particular, preventive oral care use is highest among white Americans and the lowest among black Americans and American Indians, with Hispanic and Asian Americans somewhere in between (H₂) (2, 5, 6).

Third, on the basis of the Behavioral Model of the Health Services (14, 15), this study hypothesizes that racial/ethnic variations in preventive dental care utilization are partially accounted for by heterogeneity in predisposing factors (e.g., demographic characteristics and health behavior), enabling factors (e.g., education, income), and needs (e.g., health conditions). With regard to predisposing factors, females and married individuals are more likely to seek regular dental care (8, 13). Evidence has consistently shown that smoking is a risk factor for oral health (16, 17) and individuals who smoke use dental services less often (7, 18). Compared to those who abstain from drinking alcohol, one study found that moderate drinkers had a higher use of dental care (19). One study has shown that the relationship between number of teeth and body mass index (BMI) is not linear. Individuals who were either underweight or obese were more likely to have fewer teeth compared with those who were normal weight (20). Enabling characteristics are the personal resources available to an individual that enable or impede the use of health services. Studies found that individuals with higher levels of education and income are more likely to use dental services (8, 21–23). A growing body of literature suggests that oral health and dental care use are associated with diabetes, cardiovascular diseases, and respiratory diseases (24–28). Individuals with a higher number of natural teeth are more likely to seek preventive dental care (11, 19). Need exists when an individual utilizes healthcare services based on their illness (29). Literature also suggests that oral health and dental care use are associated with diabetes, cardiovascular diseases, and respiratory diseases (24–28).

This is the first study to provide national estimates for dental cleaning and associated trends over time for five major ethnic groups aged 50 and above in the U.S. simultaneously: American Indian/Alaskan Native, Asian Americans, Blacks, Hispanics, and non-Hispanic Whites. Most previous studies on trend of dental care use have focused on children and young adults, with just a small number on aged 50 and above (2, 8). Given the increasing number of middle-aged and older adults in the U.S who need dental care, research is needed to examine the trend of dental care use and factors related to dental care use in this segment of the population.

The results support the first hypothesis that use of preventive dental care continued to increase between the period of 1999 and 2008, extending beyond the previously reported increase for the periods of the 1970s and 1990s (2, 3). However, the increase in dental care was largely explained by heterogeneity in socio-demographic and health attributes over time. The second hypothesis (H₂) was also supported by the study findings. Blacks and American Indians had the lower predicted rate of preventive dental care in the U.S. The study also supports the third hypothesis (H₃) that racial/ethnic variations in preventive dental care utilization are partially accounted for by population heterogeneity. There were differences in dental care use over time between White and minority groups. However, these differences in dental cleaning over time between White Americans and other minority groups, except Blacks, can be explained by socio-demographic and health characteristics. Differences between Blacks and Whites persisted even when population heterogeneity was adjusted. The results from product terms suggest that there were no significant trend differences across racial/ethnic groups with regarding to preventive dental care over the past 10 years.

This study found that health insurance, education, income, smoking, and the number of natural teeth were among the covariates that were associated with dental cleanings. The steadily rising level of education over the past 10 years may partially contribute to the increase of preventive dental care use over the same time period (32). Education is a key to promoting healthy behaviors (21). Individuals with a higher level of education may have better knowledge of oral health practices, and the risks associated with dental care neglect. Health insurance and income could reflect an enabling issue and be indicative of improved access to dental care with greater resources.

Having a dental cleaning in the past year could reflect a positive health seeking behavior. Specifically, smoking was found to have a negative effect on the likelihood of a dental cleaning, indicating less of a positive health seeking attitude for smokers. This finding is of substantial importance, as smokers’ oral health is not only affected by the use of tobacco, but also by the neglect of under-utilizing dental care. Use of tobacco and dental care may be inversely related. The recent decreasing use of tobacco and the increase use of preventive dental care are likely associated with greater awareness of health issues in the U.S. Women were more likely to have a cleaning than men. The results confirm the findings from previous studies (8, 13) and are also consistent with the literature on preventive medical care (33, 34). Some researchers speculate that women’s more frequent preventive health services use relates to their acceptance of help seeking, compliance with treatment regimens, and willingness to adopt the sick-role (33–35). Thus, targeting health attitudes and behaviors that vary with gender might be the most effective strategies for producing changes in preventive dental care.

This study expanded upon previous studies by adjusting potential confounding factors and found improvements in dental care utilization were not equally distributed across the ethnic groups. Compared to Whites, Blacks were less likely to utilize dental care; however, the magnitude of the disparity decreased when controlling for socioeconomic status, medical conditions, health behaviors, and the presence of permanent teeth. These findings suggest the presence of other systematic differences in factors between the Black and White groups in regard to receiving dental cleanings, and issues such as quality of dental care and priority of use of preventive health services, may help to explain these findings.

The current study goes beyond that of prior research by comparing Asians to Whites in addition to other ethnic groups. After controlling for covariates, the disparities in dental care utilization between Asians and Whites are no longer present. However, the results are likely to be inconclusive given the caveat of the BRFSS sample excluding non-English speaking individuals in the study. The rates of dental cleaning for Asian Americans in our study were higher than the rate reported from Wu et al.’s (7) study conducted among Chinese American elders aged 60 and older in 2000. One major reason for the rate discrepancy is likely due to the differences in data collection: the previous one was conducted in Chinese and the BRFSS survey was conducted in English. According to the 2009 U.S. Census data, 32% of Asian Americans have limited English proficiency. Lack of English proficiency is most common for Vietnamese (51%), Koreans (41%), and Chinese (42%) (36). Given the fact that national surveys, such as BRFSS, do not interview Asian Americans in their native language, the surveys are most likely to exclude individuals who have limited English language skill, and consequently, by large, excluding those with lower SES. Individuals with different levels of SES are likely to have different pattern of preventive dental care. The Asian population in the United States warrants researchers’ attention as it is growing at a faster rate than any other ethnic groups, and is exceptionally diverse (37). Noting the heterogeneous nature of the Asian American population, past research has examined how subgroups within the Asian population compare to each other in regard to dental care utilization (6), and future research could be conducted to show how these subgroups compare to a White reference group and other minority groups.

This study also provides new knowledge on dental care use among American Indians. Prior research has identified the problems many American Indians/Alaskan Natives may face in seeking medical care (5). Other research has documented that American Indians/Alaskan Natives utilize general healthcare at lower rates in comparison to Whites; however, like the findings of the current study, these disparities are no longer present after adjusting for other factors, such as education, income, health insurance, and health behaviors (38). The findings suggest that much of the disparity of preventive dental care for American Indians could be explained by their low socioeconomic status and unhealthy behavior such as smoking. Many of the American Indians reside on reservations. Looking past the dental care utilization of American Indians and focusing on the quality of care American Indians receive through Indian health services (IHS); reports have indicated that American Indians do not receive adequate dental care. For reasons such as salary levels, length of commitment, more attractive employment opportunities elsewhere, and other factors, recruitment and retention of dental health care professionals has become a continuing and worsening problem for IHS. Currently, 32% of full-time dental positions in IHS are vacant, an all-time high (4). For this reason, current SES or contemporary barriers to dental care may not fully capture the experience and problems American Indians/Alaskan Natives face in securing consistent and adequate care, and lower utilization may indicate an accumulation of disadvantages over time.

While some evidence suggests the association between oral health and systemic health (39), our study did not find a significant association between dental care use and many chronic conditions. It is possible some of the association is explained by other factors such as socioeconomic status, health behaviors (e.g., smoking) that are included in the study. Further study is warranted to further examine the complex relationship between oral health, dental care, and systemic diseases.

An overall upward trend in dental care utilization between 1999 and 2008 was observed; however there were some significant differences and variations across the five major racial/ethnic groups. Public health programs with an emphasis on educating and enabling middle-aged and older minority populations to the benefits of oral health could have a large impact, as there is much room for improvement. Given the importance of oral health and a population that is rapidly becoming older and more diverse the need for improved access to dental care is significant.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The Associate Editor Jie Hu declares that, despite being affiliated with the same institution as the author Robert Furter, the review process was handled objectively and no conflict of interest exists.