Challenges and Solutions for Improved Oral Health: Examples from Motivational Interviewing Trials

Knowledge Transfer Statement:

Irrespective of country, socially disadvantaged children experience greater levels of preventable dental disease than their more socially advantaged peers. Motivational interviewing (MI) is recognized as a potential intervention tool for reducing prevalence of child dental disease. The challenges of implementing MI in 4 trials involving socially vulnerable children are highlighted in this commentary, with some potential solutions offered.

Social determinants play a profound role in shaping and sustaining inequities in oral health. Regardless of health service delivery models, geographic location, or a country’s Organisation for Economic Co-operation and Development ranking, socially disadvantaged children experience higher levels of preventable dental disease than the more socially advantaged.

Theory-based behavioral interventions have been implemented in both dental health research and practice, aiming to reduce oral health inequalities. Motivational interviewing (MI) has received considerable recent attention in this light. MI is based on the proposition that behavior change is more likely with internal motivation, with movement along the readiness-to-change continuum considered an acceptable short-term outcome since motivation comes before action. The success of MI depends on fidelity and competence of the interventionist, particularly in the use of strategies that elicit clients’ statements of self-motivation and avoidance of behaviors that increase resistance to behavior change. MI is a reasonably complex intervention, requiring proficiency to attain the best client outcomes.

The findings of 4 randomized trials of MI to prevent early childhood caries (ECC) in high-risk populations have recently appeared: 1 among African Americans in Detroit (Ismail et al. 2011), 1 among public housing residents in urban Boston (Henshaw et al. 2018), 1 among rural American Indian families in South Dakota (Batliner et al. 2018), and 1 among Aboriginal families in South Australia (Jamieson et al. 2018; Jamieson et al. 2019). The Detroit study was a trial embedded in a cohort study targeting low-income, inner-city African American families (carer and child aged 0 to 5 y). MI was delivered 1 time to carers of children in the intervention group. Both intervention and control groups received oral health education via DVD. The MI intervention resulted in improvements of some oral health behaviors at 6-mo and 2-y follow-ups, but there were no clinical differences in child oral health. The Boston study was a community-based, cluster-randomized controlled trial among 1,065 children aged 0 to 5 y at baseline. It tested the effect of MI on incident caries over 2 y, with MI delivered quarterly with high fidelity to protocol. All children received periodic preventive care, including quarterly fluoride varnish applications. The addition of MI had no statistically significant effect on caries outcomes. The South Dakota study was a randomized controlled trial involving primary carers of an American Indian infant aged up to 3 mo at baseline. The MI intervention was delivered shortly after childbirth and at ages 6, 12, and 18 mo. Both intervention and control groups received usual care and enhanced community services. After 3 y, there were no significant differences in the groups’ high levels of caries. The South Australia study was a 2-arm parallel, single-blind randomized controlled trial. Eligibility included being pregnant with an Aboriginal child during the enrollment period. The intervention comprised dental care to mothers during pregnancy; application of fluoride varnish to teeth of children at ages 6, 12, and 18 mo; and MI delivered in conjunction with anticipatory guidance. Rigorous training and fidelity protocols were followed. The delayed intervention group received the intervention at child age 24 mo, 30 mo, and 36 mo. At age 2 y, those in the immediate intervention group had less dental disease than delayed intervention children. This difference was maintained at age 3 y.

All studies reported challenges in trial implementation, including time required for community consultation and for employing, training, and retaining appropriate staff; extensive travel; dealing with social determinants of health-related factors outside researchers’ control (child removal from families, incarceration, death, geographic mobility, unemployment); extreme weather conditions; and multiple appointments for data collection. However, there are important differences in the studies. Due to funder obligations and community expectations, the US studies were required to provide some level of oral health promotion and/or care to the control group. Therefore, the efficacy of MI could only be tested against a background of such levels of care. While this was not the case in Australia, in this country, it was impossible to disentangle which of the 4 intervention components had the most impact on the resulting differences in caries levels; it might not have been MI at all.

In the absence of concerted population-level approaches to targeting the social determinants of health, are we perhaps expecting too much of MI? Anecdotal reports from the South Dakota study suggest that, even though MI was well received, other life challenges simply overwhelmed carers’ best intentions in terms of child oral health. Even if MI can be shown to improve risk behaviors, knowledge, attitudes, and beliefs, will that be enough to have a meaningful effect on ECC incidence among those at highest risk? And if the effectiveness of MI on reducing ECC could eventually be conclusively demonstrated, could ways be found to deliver MI in a more cost-effective manner? Just how cost-effective would it be when compared to other modalities for ECC prevention, including water fluoridation?

The 4 MI trials highlighted in this commentary were all delivered after rigorous MI training and fidelity testing, yet 3 of the interventions resulted in no change in levels of untreated child dental caries in the target population. The one that did appear to result in improvements implemented a multipronged, multidisciplinary approach, leaving unanswered the question of whether the inclusion of MI was essential to achieving the observed caries reduction. It could be that, with these high-risk and vulnerable populations, MI interventions might have limited efficacy when they are standalone but are able to achieve the desired outcomes when a more programmatic approach is used. This may be an attractive option for governments, community groups, and policy makers who want to implement a program at a universal level, for example, government-initiated school-based programs. MI was well accepted in each of the diverse populations involved in our studies. Indeed, it is considered a culturally respectful form of psychotherapy that is accepted, particularly among indigenous populations, where others are not. In considering the global aim to reduce inequalities in oral health, making MI the norm may be necessary. This includes teaching dental students to use MI in their clinical practice and to thus make it an overall norm in oral health behavior change. MI should therefore not just be secluded for use among indigenous and other underserved populations.

Author Contributions

L.M. Jamieson, contributed to conception and data interpretation, drafted and critically revised the manuscript; R.I. Garcia, W. Sohn, J. Albino, contributed to conception and data interpretation, critically revised the manuscript. All authors gave final approval and agree to be accountable for all aspects of the work.