ADA study finds poor quality of evidence to support MLPs

A review of the research on irreversible procedures performed by midlevel providers (MLPs) concludes the evidence is too poor to compare the effectiveness of their treatment with that of dentists, according to a yearlong systematic review conducted by the ADA (Journal of the American Dental Association, January 2013, Vol. 144:1, pp. 75-91).

Some groups treated by MLPs had fewer caries over time, but other groups showed no difference in the overall rate of caries between those treated by MLPs and dentists, according to an analysis of 18 studies that focused on certain criteria.

The survey was unable to reach definitive conclusions on whether MLPs reduce caries overall or if they are more cost-effective than dentists.

The report's authors emphatically stressed the limitations of their investigation, writing, "Even the best studies available are of poor quality, and there is a clear need for additional research to assess the effectiveness of midlevel providers as a means to reduce overall disease burden."

Likewise, the studies contained no data regarding these providers' cost-effectiveness, the researchers concluded.

Notably, the report refuted the argument that MLPs improve access to oral care, pointing to an International Collaborative Study that concluded the availability and accessibility of oral health services were not barriers to care.

"Thus, the hypothesis that increasing oral health personnel power would improve oral health status and reduce treatment needs was not supported by the data," the study authors concluded. "Unfortunately, oral health disparities exist regardless of the provider workforce model."

House of Delegates mandate

The systematic review was conducted in response to a 2011 mandate by the ADA House of Delegates "that the American Dental Association, through the appropriate ADA agencies, conduct and report on a systematic review of the literature on nondentist workforce models which exist or are under development in the [United States] and other countries that include diagnosis, treatment plan formulation, and/or the performance of irreversible and/or surgical dental procedures."

The ADA's Council on Scientific Affairs chose seven dentists to do the review, including a pediatric dentist, three public health dentists, and three private practitioners. The review focused on irreversible and surgical procedures, which included cavity preparations and extractions. The diseases focused on included caries, periodontal disease, oral cancer, trauma, and malocclusion.

The study authors focused on this question: In populations where nondentists conduct diagnostic, treatment planning, and/or irreversible surgical dental procedures, is there a change in disease increment, untreated dental disease, and/or cost-effectiveness of dental care?

A search of 13 databases yielded 7,701 potentially applicable citations, eventually yielding 18 studies that met the reviewers' inclusion criteria. The studies included those done in Australia, Canada, Hong Kong, New Zealand, and the U.S.

Of the 18 studies, some were quite old, the study authors noted, having been published as early as the 1950s. Seven were published prior to 1980. Twelve were judged to be at high risk of bias, five at moderate risk, and one at low risk. Notably, the researchers found no randomized, controlled studies and no data regarding cost-effectiveness, irreversible diagnostic procedures, or diseases other than caries.

The authors also noted that World Health Organization data clearly document decreases of up to 80% in caries in developed nations during the past 40 years, which have coincided with many changes in oral health prevention and attitudes toward oral health, and that this change has occurred irrespective of the makeup of the dental workforce.

Even so, they found that in select groups in which participants received irreversible dental treatment from teams that included midlevel providers, caries increment, caries severity, or both decreased across time; however, they found no difference in caries increment, caries severity, or both compared with those in populations in which dentists provided all irreversible treatment.

In select groups in which participants had received irreversible dental treatment from teams that included midlevel providers, the study authors found a decrease in untreated caries across time and a decrease in untreated caries compared with that in populations in which dentists provided all treatment. This is likely a result of a greater number of nondentists available to treat caries, they noted.

"The ADA systematic review found no evidence to support claims that utilizing new workforce models to perform surgical treatments improves the caries experience of the affected populations," wrote lead author Timothy Wright, DDS, MS, in a commentary accompanying the JADA study. "In fact, one of the most significant findings is that despite decades of use of these workforce models in numerous countries, there is no apparent reduction in disease incidence."

Part of the solution

But Shelly Gehshan, director of the Pew Children's Dental Campaign, said the report confirms other studies that show MLPs have a positive effect on oral health.

"It confirms what we've known all along, which is that MLPs provide high-quality care to children and adults, and the populations they serve have similar health outcomes to those served by dentists. There's a decrease in untreated disease," she told DrBicuspid.com. "These are good things; we should be happy about this."

Gehshan continued: "Our challenge is to figure out how to deploy all the providers in our dental team to reach people who don't get care now. They're asserting that MLPs do not reduce overall rates of decay, so my question to them would be: Do dentists?"

Nearly 50 million people live in underserved areas, and one-third of the population still lacks access to care, she added, pointing to a report by the Institutes of Medicine that concluded providers of all types will improve oral health.

"We also need a mix of providers in a wider array of settings, and MLPs can be a part of an overall solution," Gehshan said.

Approximately 1 million people turn to hospital emergency rooms annually for treatment of preventable dental problems, she pointed out.

"This is why we end up with young children in operating rooms with bombed out mouths," Gehshan said. "We have many sentinel events showing our system is just failing too many people."

Study limitations

But Dr. Wright maintains that the available literature does not address disease other than caries and revealed no evidence related to the cost-effectiveness of utilizing these providers in place of dentists.

"Most significantly, there is no apparent difference in caries increment between populations receiving care from various alternative workforce models that perform surgical procedures and those receiving the same services solely from dentists," he wrote.

While the report concluded that using MLPs resulted in fewer and less serious caries over time, there was no difference when compared with populations by providers other than midlevel providers, according to W. Carter Brown, DMD, vice president of the Academy of General Dentistry (AGD).

"These [results] may seem confusing," Dr. Brown stated, "but actually all this is saying is that filling more cavities mean that more cavities were filled, but that the introduction of nondentists into the mix did not improve the overall oral health of the population. It did not reduce the number of individuals experiencing caries."

In addition, the review could not find any data on the cost-effectiveness of dental care provided by the midlevel providers in these countries, the AGD noted.

"The reviewers did not answer the question. The focus of the review is on dental teams that incorporate midlevel providers, not on midlevel providers acting independently or without supervision," said AGD Speaker of the House W. Mark Donald, DMD, MAGD, in a press release. "So the conclusions of the review speak to the effects of increasing the size of the dental team, not to the effects of replacing dentists with midlevel providers."

The report reinforces the position that the MLP treatment strategy will not achieve improved oral health outcomes, the AGD emphasized. "To achieve improved health, we must turn our attention and resources to prevention, oral health literacy issues, and better utilization of existing services," the organization stated in the release.

The ADA has steadfastly opposed allowing MLPs to do restorations and extractions, and has released reports that concluded the MLP model is not economically realistic or sustainable.

"To put it simply, this report shows that if more personnel are treating cavities, more cavities get treated," stated ADA President Robert Faiella, DMD, MMSc, in a press release. "But that does nothing to reduce the number of people getting cavities. And it points [to] the futility of a delivery system based on surgically treating disease that could have been prevented."