Abstract
Background
Medicaid programs may have a salient financial incentive to provide adult coverage for cost-effective preventive dental procedures because they face responsibility for catastrophic costs of dental disease. Whether there is sufficient evidence to support adult Medicaid coverage of preventive dental services is unclear.
Methods
Using an optimal insurance model, the author examines what evidence there is to support coverage of cost-effective preventive dental services in Medicaid and what evidence gaps remain.
Results
There is insufficient evidence to support adult Medicaid coverage for preventive dental procedures.
Conclusions
More research is needed to identify preventive dental procedures that are cost-effective from a Medicaid perspective, quantify the impact dental prevention has on dental-related health care costs and overall health care costs, and quantify the impact patient-side and provider-side financial incentives have on take-up of specific preventive dental treatments.
Practical Implications
Although Medicaid programs may have an interest in preventing catastrophic costs of dental disease (that is, dental-related emergency department visits), there is insufficient evidence for Medicaid programs to provide coverage for preventive dental procedures.
Key Words
Abbreviation Key:
ED (Emergency department), EE (Economic evaluation), QoL (Quality of life)
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
or to generally attain optimal oral health.
In addition, dental benefits do not provide insurance in the traditional sense. Rather than providing coverage for low-risk, high-expenditure adverse oral health events, dental benefits are structured instead as prepayment plans for routine dental procedures perceived as preventive, but with little proven clinical efficacy.
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
,
- Orynich C.A.
- Casamassimo P.S.
- Seale N.S.
- Reggiardo P.
- Litch C.S.
Dental benefits are generally purchased separately from health insurance plans and are offered by insurers offering dental benefits only and not health insurance (that is, stand-alone dental insurers).
due to predictable routine procedure use, annual caps, and high co-payments for restorative procedures.
In addition, dental insurers’ costs do not vary substantially with patients’ underlying dental risk or oral health status. Because there is no tie between costs of providing dental benefits and patients’ risk and health, dental insurers have little incentive to cover procedures decreasing the probability of adverse events or improving patient health. Instead, catastrophic dental costs are turned over to health insurers, emergency departments (EDs), or absorbed by patients.
The only salient incentive for dental insurers to provide coverage is if consumers will opt out of plans without coverage of clinically effective preventive services.
This is because Medicaid programs do bear costs from catastrophic oral health events, primarily through dental-related ED visits. In addition, EDs are generally not equipped or prepared for treating dental conditions
,
,
and instead provide palliative care (that is, antibiotics and analgesics) requiring follow-up treatment at a dental office.
- Darling B.G.
- Singhal A.
- Kanellis M.J.
Therefore, dental-related ED expenditures represent both catastrophic costs and costs for services ineffective at addressing caries.
- Darling B.G.
- Singhal A.
- Kanellis M.J.
Researchers have reported that Medicaid programs are the largest payers of dental-related ED visits.
,
These preventable costs should be an increasingly urgent concern, as dental-related ED visits have surged in the past decade.
,
,
,
- Vujicic M.
- Buchmueller T.
- Klein R.
Although Medicaid is the primary source of dental coverage for low-income adults, adult dental coverage is often among the first benefits cut in response to Medicaid budgetary constraints.
As a result, low-income adults can experience large fluctuations in dental coverage access and oral health care affordability.
,
- Vujicic M.
- Buchmueller T.
- Klein R.
Even among children, who are federally required to have access to Medicaid coverage comprehensive dental services, there still exists variation in coverage and reimbursement for clinically effective dental prevention.
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
The variation and fluctuation in Medicaid dental benefits indicates uncertainty among Medicaid programs in deciding what dental procedures warrant coverage.
,
- Manning W.G.
- Newhouse J.P.
- Duan N.
- Keeler E.B.
- Leibowitz A.
This increase in insurer costs might then cause Medicaid state programs to increase premiums or taxes. Because lower premiums and tax stability may be prioritized for tax-financed public insurance,
Medicaid programs would then typically prefer covering interventions not requiring premium or tax increases.
,
- Listl S.
- Grytten J.I.
- Birch S.
Therefore, economists study and model optimal resource allocation as a constrained optimization problem. The form of the constrained optimization problem depends on the decision makers’ perspective and trade-offs.
Methods
encapsulates primary trade-offs faced by health insurers when adding coverage for preventive services and identifies key factors influencing the optimal coverage level for a specific treatment. The model takes the perspective of a health insurer considering whether to add coverage for a new treatment to an existing plan. The insurer’s constrained optimization problem is a premium minimization problem because public and private insurers are constrained from raising premiums, either from difficulties in raising taxes to fund higher premiums or substantial transaction costs from renegotiating higher health insurance premium, on existing plans. Because adding coverage affects present and future expected costs for both insurers and consumers, the model includes information on whether incurring the cost of the new service now will lower future expected medical costs and consumers’ responses to increased coverage and the decreased out-of-pocket costs for a specific treatment. This highlights that providing coverage for a cost-effective preventive service (when using the service lowers total expected medical spending) decreases total insurer expenses only under certain conditions. When these conditions are fulfilled, insurers are more likely to offer coverage for cost-effective preventive services. These conditions are as follows:
- ▪at minimum, use of the preventive service offsets the insurer’s future expected medical costs21Benign moral hazard and the cost-effectiveness analysis of insurance coverage.
;
- ▪that there is not already a large proportion of people purchasing the preventive service without insurance21Benign moral hazard and the cost-effectiveness analysis of insurance coverage.
;
- ▪consumers are responsive to price changes for the service21Benign moral hazard and the cost-effectiveness analysis of insurance coverage.
;
- ▪coverage increases take-up of the service.21Benign moral hazard and the cost-effectiveness analysis of insurance coverage.
and what evidence gaps remain. I did this by first identifying what dental prevention has been deemed to be cost-effective in the literature and then by reviewing the portions of the dental literature pertaining to each Pauly and Held
condition. I drew from systematic literature reviews where possible and assessed whether conclusions from the literature were robust enough to support each condition.
What preventive dental interventions have been found to be cost-effective?
Economic evaluations (EEs) characterize the trade-offs involved in including coverage for dental treatments and can be used for decision making and policy-making. In particular, EEs can quantify trade-offs between increased cost of providing a treatment and improvements in health outcomes. These trade-offs may be particularly relevant for Medicaid, which may be interested in not only health care expenditures, but also social welfare and population health. Because Medicaid programs budget for overall health, EEs can be informative for policy-makers and decision makers as to whether the increased costs from providing coverage for a dental treatment is worth the gain in overall health (that is, is cost-effective).
caries prevention EEs are modest in number and quality, primarily indicating prevention is cost-effective for specific populations and countries.
- Niederman R.
- Feres M.
- Ogunbodede E.
Because methods and outcomes used for caries prevention EEs are highly heterogenous,
- Tan S.H.X.
- Vernazza C.R.
- Nair R.
,
- Tonmukayakul U.
- Calache H.
- Clark R.
- Wasiak J.
- Faggion Jr., C.
only water fluoridation and targeted sealing of fissures in patients at high risk of developing caries were concluded to be cost-effective among evaluated caries prevention in a 2019 scoping review.
- Eow J.
- Duane B.
- Solaiman A.
- et al.
In addition, health outcomes and costs included in these EEs tend to exclude outcomes of interest to Medicaid. These outcomes are quality-of-life (QoL),
- Tonmukayakul U.
- Calache H.
- Clark R.
- Wasiak J.
- Faggion Jr., C.
,
- Rogers H.
- Rodd H.
- Vermaire J.
- et al.
,
systemic health,
- Tonmukayakul U.
- Calache H.
- Clark R.
- Wasiak J.
- Faggion Jr., C.
,
- Rogers H.
- Rodd H.
- Vermaire J.
- et al.
,
and economic costs.
- Tonmukayakul U.
- Calache H.
- Clark R.
- Wasiak J.
- Faggion Jr., C.
Oral diseases can have drastic effects on QoL in terms of functioning, pain, and self-perception.
- Cunningham S.
- Sculpher M.
- Sassi F.
- Manca A.
,
- Hettiarachchi R.M.
- Kularatna S.
- Downes M.J.
- et al.
Such effects on QoL might not be captured when examining naturally occurring dental outcomes, that is, caries. Therefore, whether an EE assesses QoL outcomes can drastically alter study conclusions. In addition, Medicaid likely optimizes budgets for providing overall health care coverage, not just oral health care coverage. In this case, EEs should include health outcomes comparable across a broad set of medical and dental interventions.
- Hettiarachchi R.M.
- Kularatna S.
- Downes M.J.
- et al.
Among these 23 EEs, only 3 evaluated dental prevention,
- Bhuridej P.
- Kuthy R.A.
- Flach S.D.
- et al.
,
- Ciketic S.
- Hayatbakhsh M.R.
- Doran C.M.
,
and only 1 evaluated a nonpublic oral health intervention.
- Bhuridej P.
- Kuthy R.A.
- Flach S.D.
- et al.
Future work assessing whether dental prevention is cost-effective should include QoL.
Oral health intervention EEs exclude other outcomes of interest to Medicaid, such as economic and systematic health outcomes. For instance, economic outcomes (that is, education, school attendance, income, and days missed at work) can affect whether dental interventions are cost-effective to Medicaid. Excluding medical outcomes (that is, ED and primary care visits averted for dental-related conditions) can affect this as well. Future dental intervention EEs should incorporate all outcomes of interest to Medicaid.
Would providing coverage for dental prevention offset future costs to Medicaid among adults?
,
,
Providing dental prevention coverage to address unmet dental need may prevent Medicaid dental-related ED costs.
- Baicker K.
- Allen H.L.
- Wright B.J.
- Taubman S.L.
- Finkelstein A.N.
Investigators examining the Patient Protection and Affordable Care Act found Medicaid expansions including adult dental coverage led to decreased dental ED visits.
- Elani H.W.
- Kawachi I.
- Sommers B.D.
,
- Elani H.W.
- Simon L.
- Ticku S.
- Bain P.A.
- Barrow J.
- Riedy C.A.
Both are consistent with researchers suggesting that reducing Medicaid adult coverage leads to more people seeking oral health care in EDs.
- Wallace N.T.
- Carlson M.J.
- Mosen D.M.
- Snyder J.J.
- Wright B.J.
,
- Laniado N.
- Badner V.M.
- Silver E.J.
,
- Chalmers N.
- Grover J.
- Compton R.
,
- Singhal A.
- Caplan D.J.
- Jones M.P.
- et al.
,
,
- Cohen L.A.
- Manski R.J.
- Hooper F.J.
With ongoing public and private health insurance expansions through the Patient Protection and Affordable Care Act, this may indicate dental-related ED visits might continue increasing if expansions do not include increased dental coverage and timely oral health care access. This suggests a financial interest for Medicaid in identifying what dental treatments can offset dental-related medical costs.
,
- Allareddy V.
- Rampa S.
- Lee M.K.
- Allareddy V.
- Nalliah R.P.
and could be treated at lower cost by dentists.
Researchers have also suggested that regular preventive dental visits decrease restorative dental services use,
which may be a substitute for dental-related ED visits. However, the authors of a 2019 scoping review of dental-related ED visit determinants found no articles examining the effect of specific dental prevention on dental-related ED visits.
- VanMalsen J.R.
- Figueiredo R.
- Rabie H.
- Compton S.M.
Instead, the literature focused only on macro-level factors and was primarily associational.
- VanMalsen J.R.
- Figueiredo R.
- Rabie H.
- Compton S.M.
Examining the causal effect would require longitudinal retrospective data on medical and dental claims data, as well as causal inference methods
,
- Listl S.
- Jürges H.
- Watt R.G.
,
- Glass T.A.
- Goodman S.N.
- Hernán M.A.
- Samet J.M.
,
if randomized controlled trials with claims data follow-up are not possible.
There was limited evidence for the impact dental interventions have on health care costs for chronic conditions
- Elani H.W.
- Simon L.
- Ticku S.
- Bain P.A.
- Barrow J.
- Riedy C.A.
and insufficient evidence for the directionality and magnitude of impact dental interventions have on health care costs. Future work should leverage links between dental and medical claims data and apply robust causal inference methods in lieu of clinical trials mimicking real-world conditions.
,
- Listl S.
- Jürges H.
- Watt R.G.
,
- Glass T.A.
- Goodman S.N.
- Hernán M.A.
- Samet J.M.
,
Would adult consumers purchase preventive dental services without Medicaid coverage?
Consumers do purchase dental prevention without true insurance, but whether dental prevention purchased is cost-effective (for example, prophylaxis) and consumers purchase cost-effective dental prevention are unknown. The second point cannot be discussed without more methodologically robust literature to identify what dental prevention is cost-effective (see “What Preventive Dental Interventions Have Been Found to Be Cost-Effective?” above).
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
Rather, interventions that are likely to be cost-effective are underreimbursed relative to other common treatments under dental benefits.
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
Simultaneously, existing literature documents that dentists’ treatment behavior responds to financial incentives.
,
Consumers might not know about available and possibly cost-effective interventions (for example, sealants and silver diamine fluoride) in dental offices. Whether consumers would purchase dental prevention in dental offices without insurance cannot be determined without additional work understanding dentists’ financial incentives to provide different interventions and accounting analytically for how financial incentives affect what preventive options are offered.
- Niederman R.
- Huang S.S.
- Trescher A.-L.
- Listl S.
However, if providing cost-effective dental prevention increases likelihood of future and recall visits or decreases likelihood of patients seeking other dentists, decreases in future profit from restorative procedures might be offset by increases in future profit from future visits. Which effect dominates is an empirical question requiring data solely on out-of-pocket dental costs, which is likely only available directly from dental clinics.
Are adult consumers responsive to price changes for dental prevention?
- Meyerhoefer C.D.
- Zuvekas S.H.
- Farkhad B.F.
- Moeller J.F.
- Manski R.J.
,
- Meyerhoefer C.D.
- Zuvekas S.H.
- Manski R.
,
- Mueller C.D.
- Monheit A.C.
,
- Hay J.W.
- Bailit H.
- Chiriboga D.A.
However, the definition of preventive procedures in this literature conflates procedures with and without proven clinical efficacy (that is, sealants versus examinations or prophylaxis) in preventing caries.
- Meyerhoefer C.D.
- Zuvekas S.H.
- Farkhad B.F.
- Moeller J.F.
- Manski R.J.
,
- Meyerhoefer C.D.
- Zuvekas S.H.
- Manski R.
,
- Mueller C.D.
- Monheit A.C.
,
- Hay J.W.
- Bailit H.
- Chiriboga D.A.
Although the literature suggests dental prevention use is not responsive to out-of-pocket price changes,
- Meyerhoefer C.D.
- Zuvekas S.H.
- Farkhad B.F.
- Moeller J.F.
- Manski R.J.
,
- Meyerhoefer C.D.
- Zuvekas S.H.
- Manski R.
,
- Mueller C.D.
- Monheit A.C.
,
- Hay J.W.
- Bailit H.
- Chiriboga D.A.
more work is warranted to examine the impact out-of-pocket prices have on demand for specific procedures.
Would Medicaid coverage increase dental prevention take-up among adults?
As discussed, although changes in out-of-pocket prices might not influence demand for preventive services, whether dental coverage is available can influence whether preventive services are taken up. However, the literature is constrained by the definition of what is categorized as “preventive.” In addition, whether coverage increases take-up of cost-effective prevention depends on whether providers have sufficient financial incentive to offer these services to their patients and whether patients would opt into care.
Discussion
The existing dental research literature cannot be used to assess whether Medicaid should incorporate adult coverage for dental prevention owing to lack of methodologically robust studies examining what dental prevention is cost-effective from a Medicaid perspective; the causal impact dental prevention has on dental-related and overall health care costs; and the causal impact patient-side and provider-side financial incentives have on dental prevention take-up. Although it is established in the literature that there is a need to improve the robustness and breadth of EEs examining dental prevention, increased EEs alone are not sufficient to establish whether Medicaid or private insurers should reimburse for oral health care. Instead, increased work to quantify how dental prevention affects broader health care costs and how financial incentives affect adoption and take-up of prevention is necessary as well.
Free for All? Lessons from the RAND Health Insurance Experiment..
Limitations
model is ambiguous to the degree to which each of its conditions for coverage for cost-effective preventive services needs to be met for any dental prevention coverage to take place and the degree of coverage. However, the more investigators are able to show that dental prevention is cost-effective to Medicaid and fulfill the Pauly and Held
conditions, the more likely Medicaid state programs will have an interest in offering and increasing dental prevention coverage.
Conclusions
,
,
borne primarily by Medicaid programs. Although dental-related ED visits are largely preventable and substantial progress has been made in oral disease prevention, government investment in oral health care remains low. Direct health care expenditures on oral health care in the United States amounted to only 3.7% of total national health care expenditure in 2015,
and only 12% of this was government-funded. The lack of, and fluctuations in, access to oral health care through Medicaid has been hypothesized to be a major factor in oral health disparities in the United States.
- Fischer D.J.
- O’Hayre M.
- Kusiak J.W.
- Somerman M.J.
- Hill C.V.
Although oral health is key to maintaining and improving systemic health, there is a paucity of research quantifying the impact oral health interventions have on overall government health care expenditures, as well as overall health and QoL outcomes. This makes it difficult to communicate to policy-makers why investments in oral health should be made and why Medicaid should include coverage for dental prevention. There is an urgent need to expand health economics and health services research in dentistry.
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Biography
Dr. Huang is an assistant professor, Epidemiology and Health Promotion, College of Dentistry, New York University, 433 First Ave, New York, NY 10010.
Article Info
Footnotes
Disclosure. Dr. Huang did not report any disclosures.
This research was supported in part by grant K25 DE028584-01A1 from the National Institute for Dental and Craniofacial Research, National Institutes of Health , and by grant R01 MD011526 from the National Institute for Minority and Health Disparities , National Institutes of Health.
Identification
DOI: https://doi.org/10.1016/j.adaj.2020.05.005
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