Systematic treatment of periodontal disease: Advantage of further therapeutic approaches

Better results particularly for attachment level, more studies and analyses

Institute for Quality and Efficiency in Health Care

The German Institute for Quality and Efficiency in Health Care (IQWiG) investigated the advantages and disadvantages of different treatments of inflammatory disease of the periodontium. The final report is now available. According to the findings, there are now an indication or hints of (greater) benefit for six therapeutic approaches, mostly regarding the outcome "attachment level". In the preliminary report, this had only been the case for two types of treatment. The assessment result is now notably better because additional studies have become available to the Institute, and further analyses were possible.
In the worst case, tooth loss is possible Periodontal disease is the scientific term for disorders of the tissues surrounding the tooth, called the periodontium. The periodontium consists of the gums (gingiva), the periodontal ligament, cementum and the tooth sockets (dental alveoli), i.e. the sockets in the jaw bone that contain the roots of the teeth and keep them in place.
Periodontitis, one of the most common forms of periodontal disease, is a bacterial inflammation that occurs in the gums, for example, if food residue cannot be removed from the gingival pockets with tooth brushing. Left untreated, this can initially lead to bleeding and pus. In the long term, the periodontium may be damaged, resulting in loosening and eventual loss of teeth.
Periodontitis is a common disease. It is estimated, for example, that about 53 per cent of people aged between 35 and 44 years in Germany have a moderate form of periodontitis.
Variety of therapeutic approaches Today there is a large variety of therapeutic approaches. Besides mechanical and surgical procedures, methods also include antibiotics, laser therapy, photodynamic interventions or air-polishing systems. These methods are used to clean the gingival pockets, polish the root surfaces and kill or remove bacteria.
Not all these methods are currently covered by German statutory health insurance funds. A prerequisite for reimbursement is that the patients provide an active contribution, i.e. improve their oral hygiene (tooth brushing, flossing, etc.).
More study results usable On the one hand, the IQWiG researchers were able to include additional randomized controlled trials (RCTs) in the final report. On the other, they were able to use additional data from studies that had already been included.
This was possible for two reasons: In its literature search for the preliminary report, IQWiG had identified a number of studies investigating the appropriate research question. For many studies however, the results had been presented in the publications in a way that made them unusable for the benefit assessment. This could later be corrected for the final report. The basis for this correction was a statistical factor calculated by a team at the University of Greifswald specifically for this purpose from one of their epidemiological studies.
Analysis of data on the attachment level now possible In addition, in the oral hearing, the Institute and external experts agreed on a threshold value above which a treatment effect is to be considered as relevant to health. This threshold value allowed the inclusion of results on the outcome "attachment level" from a large number of further studies. Attachment refers to the fixation of the tooth to the jaw. The attachment level describes to what extent the periodontium is intact or destroyed.
Relevant differences in six types of treatment Conclusive study data showing health-relevant differences in the treatment results were now available for a total of six therapeutic approaches; this had been the case for only two therapeutic approaches in the preliminary report. The Institute had been able to derive a hint for each of these two, indicating a relatively low certainty of conclusions. In the final report, in contrast, IQWiG determined a hint of (greater) benefit for four treatments, and even an indication of (greater) benefit for two other treatments.
Initially, the IQWiG researchers had only been able to assess the outcome "gingivitis" (inflammation of the gums) for most of the studies. Now it was also possible to assess the attachment level for all studies.
Scaling and root planing: indication instead of hint of benefit The assessment result was better particularly for non-surgical subgingival debridement ("scaling and root planing") compared with no treatment. In scaling and root planing, suitable instruments are used to remove tartar and bacteria from the gingival pockets and plane the root surface. In view of greater gain in attachment, IQWiG now saw an indication of a benefit for this method; this had been a hint in the preliminary report.
Treatment results were better in combination with systemic antibiotic treatment than with scaling and root planing alone. Again, the attachment level was decisive for granting the indication of greater benefit. No differences between the study groups were detected for topical antibiotics, however.
Surgical interventions had no advantage Four further comparisons each showed a hint of greater benefit. In these comparisons, laser treatment and a special photodynamic method as well as instructions on oral hygiene were used, mostly in addition to scaling and root planing.
Only surgical pocket elimination as an addition to scaling and root planing resulted in a disadvantage (lesser benefit) than scaling and root planing alone.
Still hardly any data on tooth loss or side effects The newly available data, from which conclusions on benefit or harm can be derived, also only refer to "gingivitis" and "attachment level". The studies only contained sporadic data on important other criteria, such as tooth loss, side effects of treatment, or quality of life.
And there was still no evidence on structured after-care in the form of instructions on oral hygiene and regular teeth cleaning using special equipment. However, the publication of a probably decisive and with more than 1800 participants relatively large study has been announced for 2018 (IQuaD). The Institute could then conduct a supplementary assessment of these data.
Constructive use of the commenting procedure "We are pleased that our appeals had an effect and that study authors and other researchers used the commenting procedure for a constructive input of their expert opinion", says Martina Lietz, dentist and project manager of the report in the Non-Drug Interventions Department. "This cooperation was much appreciated, given that we had received such harsh initial criticism of our preliminary report", she adds. "There is now better evidence overall, even though it is still far from sufficient."
Process of report production IQWiG published the preliminary results in the form of the preliminary report in January 2017 and interested parties were invited to submit comments. At the end of the commenting procedure, the preliminary report was revised and sent as a final report to the commissioning agency in March 2018. The written comments submitted are published in a separate document at the same time as the final report. The report was produced in collaboration with external experts.

Fluoride varnish in the primary dentition can prevent caries

Whereas caries in adults and adolescents is declining, studies in children under the age of 3 have shown that caries in this age group has hardly decreased: On average, about 14% of all 3-year-olds in Germany have caries in the primary dentition. Fluoride varnish effectively helps in the remineralization of the tooth surface and prevents the development and progression of caries. The use of fluoride varnish has advantages especially for small children because it hardens quickly. Due to a lack of conclusive data it is unclear, however, whether fluoride application also has advantages regarding further patient-relevant outcomes such as tooth preservation, toothache or dental abscesses.
This is the conclusion of a rapid report published by the German Institute for Quality and Efficiency in Health Care (IQWiG) on 26 April 2018.
Primary teeth are particularly prone to caries Caries is caused by bacteria in the dental plaque, sugary foods and drinks, and a lack of oral hygiene. Children are especially likely to have caries because the enamel on baby teeth is more sensitive than the enamel on permanent teeth. Permanent teeth are sensitive at first too: When they break through, their enamel has not yet fully hardened, making it susceptible to caries. If the primary teeth already have caries lesions, subsequent permanent teeth are often also "infected" with caries at an early stage. Particularly in young children, oral hygiene and caries prevention can be challenging, however.
Children until the age of 6 years, with or without caries of their primary teeth, were included in the research question of the present rapid report: Does the application of fluoride varnish to the primary dentition have advantages in comparison with standard care without specific fluoride application?
Studies focused on caries The IQWiG researchers extracted results from 15 randomized controlled trials (RCTs), in which a total of 5002 children were treated with fluoride varnish, whereas 4705 children received no such treatment. In many studies, further measures for caries prevention in addition to the application of fluoride varnish were offered. These included trainings on oral hygiene, instructions on the correct tooth brushing technique or provision of toothbrushes and fluoridated toothpaste. The follow-up observation period was mostly two years, in some cases up to three years.
The outcome "caries" was investigated in all studies; side effects were investigated in almost all studies. Further outcomes such as tooth loss, toothache, dental abscesses or inflammation of the gums (gingivitis) were only rarely investigated. The respective data showed no difference between intervention and control group so that no conclusions on advantages or disadvantages of fluoride varnish application could be derived. Data on oral health-related quality of life were lacking completely.
Fluoride varnish promotes remineralization A clear advantage of fluoride varnish was determined despite the very heterogeneous study results: Caries of primary teeth was less common after application of fluoride varnish than without it. This treatment could completely prevent caries in about every 10th child. And it would at least reduce progression of caries in further children. Apparently, it did not make a difference for the benefit of the fluoride varnish whether the children already had caries or whether their teeth were completely intact.

Study: Drug-filled, 3-D printed dentures could fight off infections

Nearly two-thirds of the U.S. denture-wearing population suffer frequent fungal infections that cause inflammation, redness and swelling in the mouth.
To better treat these infections, called denture-related stomatitis, University at Buffalo researchers have turned to 3-D printers, using the machines to build dentures filled with microscopic capsules that periodically release Amphotericin B, an antifungal medication.
A study describing the work, recently published in Materials Today Communications, found that the drug-filled dentures can reduce fungal growth. Unlike current treatment options, such as antiseptic mouthwashes, baking soda and microwave disinfection, the new development can also help prevent infection while the dentures are in use.
Video/Photo: https://bit.ly/2qVC9pG
"The major impact of this innovative 3-D printing system is its potential impact on saving cost and time," says Praveen Arany, DDS, PhD, the study's senior author and an assistant professor in the Department of Oral Biology in the UB School of Dental Medicine.
The technology allows clinicians to rapidly create customized dentures chair-side, a vast improvement over conventional manufacturing that can vary from a few days to weeks, says Arany, who also has an appointment in UB's Department of Biomedical Engineering, a joint program in the Jacobs School of Medicine and Biomedical Sciences at UB and the School of Engineering and Applied Sciences.
Applications from this research, says Arany, could be applied to various other clinical therapies, including splints, stents, casts and prosthesis.
"The antifungal application could prove invaluable among those highly susceptible to infection, such as the elderly, hospitalized or disabled patients," he says.
The dental biomaterials market - worth more than $66 billion in 2015 - is expected to grow 14 percent by 2020. A large part of the industry is focused on dental polymers, particularly the fabrication of dentures.
UB researchers printed their dentures with acrylamide, the current go-to material for denture fabrication. The study sought to determine if these dentures maintained the strength of conventional dentures and if the material could effectively release antifungal medication.
To test the strength of the teeth, researchers used a flexural strength testing machine to bend the dentures and discover their breaking points. A conventional lab-fabricated denture was used as a control. Although the flexural strength of the 3-D printed dentures was 35 percent less than that of the conventional pair, the printed teeth never fractured.
To examine the release of medication in the printed dentures, the team filled the antifungal agent into biodegradable, permeable microspheres. The microspheres protect the drug during the heat printing process, and allow the release of medication as they gradually degrade.
The investigation involved the development of an innovative form of acrylamide designed to carry antifungal payloads, and a novel syringe pump system to combine the dental polymer and microspheres during the printing process.
The dentures were tested with one, five and 10 layers of material to learn if additional layers would allow the dentures to hold more medication. The researchers found the sets with five and 10 layers were impermeable and were not effective at dispensing the medication. Release was not hindered in the more porous single layer, and fungal growth was successfully reduced.
Future research aims to reinforce the mechanical strength of 3-D printed dentures with glass fibers and carbon nanotubes, and focus on denture relining. - the readjustment of dentures to maintain proper fit.

Drinking affects mouth bacteria linked to diseases

When compared with nondrinkers, men and women who had one or more alcoholic drinks per day had an overabundance of oral bacteria linked to gum disease, some cancers, and heart disease. By contrast, drinkers had fewer bacteria known to check the growth of other, harmful germs. These are the main findings of a study published in the journal Microbiome online April 23 and led by NYU School of Medicine researchers.
"Our study offers clear evidence that drinking is bad for maintaining a healthy balance of microbes in the mouth and could help explain why drinking, like smoking, leads to bacterial changes already tied to cancer and chronic disease," says study senior investigator and epidemiologist Jiyoung Ahn, PhD.
According to Ahn, associate director of population sciences at NYU Langone Health's Perlmutter Cancer Center, her team's study offers evidence that rebalancing some of the 700 types of bacteria in the mouth, or oral microbiome, could potentially reverse or prevent some health problems tied to drinking. Ahn says roughly 10 percent of American adults are estimated to be heavy drinkers, which experts define as consumption of one or more drinks per day for women, and two or more drinks per day for men.
Doctoral student and study first author Xiaozhou Fan, MS, says previous studies have examined alcohol consumption and its broad links to disease and some changes in the microbiome, but the new report is the first to directly compare drinking levels and their effects on all oral bacteria. Previous work at NYU Langone and elsewhere has tied the risk for head and neck cancers, and for gastrointestinal cancers, to microbial changes in the mouth.
Specifically, drinkers had more of the potentially harmful Bacteroidales, Actinomyces, and Neisseria species, and fewer Lactobacillales, bacteria commonly used in probiotic food supplements meant to prevent sickness.
The study involved 1,044, mostly white participants between the ages of 55 and 87. All came from two ongoing, national cancer trials, and all were healthy when they enrolled in either study and provided mouthwash samples of their oral microbiome, along with detailed information about their alcohol consumption. Laboratory testing was then used to genetically sort and quantify the oral bacteria among the 270 nondrinkers, 614 moderate drinkers, and 160 heavy drinkers. Results were plotted on graphs to determine which bacteria in drinkers stood out -- and grew more or less -- than in nondrinkers.
Researchers note that while their study was large enough to capture differences between bacteria among drinkers and nondrinkers, more people would be needed to assess any microbiome differences among those who consumed only wine, beer, or liquor. Some 101 wine-only drinkers were involved in the latest study, in addition to 39 who drank only beer and 26 who drank only liquor.
Ahn, an associate professor at NYU Langone in the Department of Population Health, says her team's next steps are to work out the biological mechanisms behind alcohol's effects on the oral microbiome. And she emphasized that her work is still a long way from determining if blocking or promoting any particular changes in the microbiome would lead to healthy bacteria levels similar to those found in nondrinkers.
Possible explanations for drinking-related microbiome imbalances, Ahn says, could be that acids in alcoholic beverages make the oral environment hostile for certain bacteria to grow. Another reason, she says, could be the buildup of harmful byproducts from alcohol's breakdown, including chemicals called acetaldehydes, which along with the harmful toxins in the mouth from tobacco smoke, are produced by certain bacteria, such as Neisseria.

Statins save lives of people with high levels of LDL cholesterol

Cholesterol-lowering drugs are more likely to save thousands of additional lives when used in people with higher levels of LDL cholesterol, or "bad" cholesterol, according to a new study from the University of Iowa, published in the Journal of the American Medical Association (JAMA).

Jennifer Robinson, a physician, professor of epidemiology in the UI College of Public Health, and study coauthor, says the findings show that doctors should more aggressively treat patients who have high levels of LDL cholesterol with statins, and patients should feel safe using them.

"Statins are the safest drugs we have to reduce the risk of heart attacks, strokes, and death in a wide range of patients," says Robinson. "Patients with higher LDL cholesterol levels are likely to experience even greater health benefits from taking statins and some of the newer cholesterol drugs."

The study analyzed 34 previous studies that involved more than 270,000 participants. The analysis found that statins were more likely to reduce the risk of death when LDL cholesterol levels were 100 milligrams per deciliter (mg/dl) or greater, whether or not they were used with other LDL-lowering drugs.

Robinson says the study found the lives of an additional 4.3 in 1,000 people were saved every year when treated with LDL cholesterol lowering therapy. The greatest benefit--and the greatest reduction in death rates--came to those with the highest levels of LDL cholesterol, she says.

LDL cholesterol causes fat and plaque to build up in arteries, increasing the risk for heart attacks and strokes. Levels below 100 mg/dl are considered optimal, as people with that reading are less likely to develop cholesterol plaques as they age. Readings above 100 mg/dl are considered unhealthy.

Given that 12.4 percent of American adults--or about 30 million people--have LDL levels above 160 mg/dl, Robinson says the findings show statins save tens of thousands of lives annually.

"Unfortunately, most Americans with higher cholesterol levels are not treated, and lives are unnecessarily being lost," she says.

Those with excess LDL can reduce their levels through an improved diet, increased exercise, and by taking medications such as statins. People who already have cardiovascular disease or genetic causes of high cholesterol also may benefit from adding other LDL-lowering drugs to statin therapy.

The study shows that LDL-lowering drugs can be effective for preventing heart attacks and stroke in people with risk factors even when LDL cholesterol levels are low, but even more heart attacks and death are prevented when people have LDL levels above 100 mg/dl.

The study, "Lipid lowering and mortality and cardiovascular outcomes," was published in the April 3, 2018, issue of JAMA

Ibuprofen, acetaminophen more effective than opioids in treating dental pain

Opioids are not among the most effective--or longest lasting--options available for relief from acute dental pain, a new examination of the results from more than 460 published studies has found.

Ibuprofen and other nonsteroidal anti-inflammatory drugs (NSAIDs) alone or in combination with acetaminophen are better at easing dental pain, according to new research conducted with the School of Dental Medicine at Case Western Reserve University.

The study examining relief of acute pain in dentistry--recently featured on the cover of The Journal of the American Dental Association--evaluated the safety and efficacy of dozens of pain-relief options.
"What we know is that prescribing narcotics should be a last resort," said Anita Aminoshariae, an associate professor in the dental school's Department of Endodontics and one of the study's authors.

Each day, more than 115 Americans die as a result of an opioid overdose, according to the National Institutes of Health.

"No patient should go home in pain," Aminoshariae said. "That means that opioids are sometimes the best option, but certainly should not be the first option."

Aminoshariae said the goal of the systematic review was to summarize data--using five in- depth studies--of the effectiveness of oral-pain medications.

"The best available data suggests that the use of nonsteroidal medications, with or without acetaminophen, offers the most favorable balance between benefits and harms, optimizing efficacy while minimizing acute adverse events," she said.
She cited the national opioid epidemic as one of many reasons why health-care providers should take note of the findings.

The research found that, for adults, a combination of 400 milligrams of ibuprofen and 1,000 milligrams of acetaminophen was superior to any opioid-containing medications studied.

"Our aim was to create a compendium detailing both the benefits and harms of these medications as a resource for dentists to use in their clinical decision-making," Aminoshariae added.

The study also found that opioids or drug combinations that included opioids accounted for the most adverse side effects--including drowsiness, respiratory depression, nausea/vomiting and constipation--in both children and adults.

Peptide-based biogenic dental product may cure cavities

Researchers at the University of Washington have designed a convenient and natural product that uses proteins to rebuild tooth enamel and treat dental cavities.

The research finding was first published in ACS Biomaterials Science and Engineering.

"Remineralization guided by peptides is a healthy alternative to current dental health care," said lead author Mehmet Sarikaya, professor of materials science and engineering and adjunct professor in the Department of Chemical Engineering and Department of Oral Health Sciences.

The new biogenic dental products can -- in theory -- rebuild teeth and cure cavities without today's costly and uncomfortable treatments.

"Peptide-enabled formulations will be simple and would be implemented in over-the-counter or clinical products," Sarikaya said.

Cavities are more than just a nuisance. According to the World Health Organization, dental cavities affect nearly every age group and they are accompanied by serious health concerns. Additionally, direct and indirect costs of treating dental cavities and related diseases have been a huge economic burden for individuals and health care systems.

"Bacteria metabolize sugar and other fermentable carbohydrates in oral environments and acid, as a by-product, will demineralize the dental enamel," said co-author Sami Dogan, associate professor in the Department of Restorative Dentistry at the UW School of Dentistry.

Although tooth decay is relatively harmless in its earliest stages, once the cavity progresses through the tooth's enamel, serious health concerns arise. If left untreated, tooth decay can lead to tooth loss. This can present adverse consequences on the remaining teeth and supporting tissues and on the patient's general health, including life-threatening conditions.

Good oral hygiene is the best prevention, and over the past half-century, brushing and flossing have reduced significantly the impact of cavities for many Americans. Still, some socio-economic groups suffer disproportionately from this disease, the researchers said. And, according to recent reports from the Centers for Disease Control and Prevention, the prevalence of dental cavities in Americans is again on the rise, suggesting a regression in the progress of combating this disease.

Taking inspiration from the body's own natural tooth-forming proteins, the UW team has come up with a way to repair the tooth enamel. The researchers accomplished this by capturing the essence of amelogenin -- a protein crucial to forming the hard crown enamel -- to design amelogenin-derived peptides that biomineralize and are the key active ingredient in the new technology. The bioinspired repair process restores the mineral structure found in native tooth enamel.

"These peptides are proven to bind onto tooth surfaces and recruit calcium and phosphate ions," said Deniz Yucesoy, a co-author and a doctoral student at the UW.

The peptide-enabled technology allows the deposition of 10 to 50 micrometers of new enamel on the teeth after each use. Once fully developed, the technology can be used in both private and public health settings, in biomimetic toothpaste, gels, solutions and composites as a safe alternative to existing dental procedures and treatments.

The technology enables people to rebuild and strengthen tooth enamel on a daily basis as part of a preventive dental care routine. It is expected to be safe for use by adults and children.

Effective school-based cavity prevention program

School-based prevention programs can substantially reduce children's cavities - but what type of treatment should be delivered in schools to best prevent tooth decay?
A new study by researchers at NYU College of Dentistry, published in the journal BMC Oral Health, suggests that cavity prevention programs with a combination of prevention strategies may be more effective than one alone for reducing tooth decay.
Dental cavities are the world's most prevalent childhood disease, affecting nearly 30 percent of school-age children and 50 percent of rural, minority, or Medicaid-receiving children in the United States.
School-based cavity prevention programs have emerged as an important way to improve access to dental services. In medically underserved areas, these programs often serve as the sole source of dental care for children. While the American Dental Association supports the use of school-based cavity prevention programs, questions remain on the optimal mix of treatment services, intensity, and frequency of care.
"Given the high variability in school-based programs to prevent cavities, comparing the effectiveness of different prevention agents, frequency of care, or intensity of treatment can lead to optimal program design," said Ryan Richard Ruff, MPH, PhD, assistant professor of Epidemiology & Health Promotion at NYU Dentistry and the study's lead author.
In this study, NYU Dentistry researchers compared two cavity prevention programs in elementary schools serving more than 8,200 students over 10 years (2004-2014). Both programs provided school-based care twice a year to children ages 5 to 12.
One program provided sealants on molars (primary prevention) while the other provided sealants on all teeth and interim therapeutic restorations (primary and secondary prevention). Interim therapeutic restorations are a minimally-invasive method for controlling tooth decay by filling a cavity with a fluoride?releasing agent. Interim therapeutic restorations are intended to bridge the gap between identifying a cavity, particularly in a nontraditional setting or in a very young child, and having the cavity filled or crowned in a more permanent procedure.
Both school-based cavity prevention programs reduced the risk of untreated decay over time. While the total number of all decayed or filled teeth observed over the course of the study increased across both programs, the comprehensive program that provided primary and secondary prevention significantly lowered the rate of new and untreated cavities when compared to only sealants on molars.
"A comprehensive cavity prevention program, particularly for children without regular access to dental care, can be significantly better than the traditional molar sealant programs," said Richard Niederman, DMD, professor and chair of the Department Epidemiology & Health Promotion at NYU Dentistry and the study's coauthor.
Ruff and Niederman are continuing to study how to optimize school-based cavity prevention. They are currently leading two large studies - a PCORI-funded study in the Bronx and an NIH-funded study in New Hampshire - to compare two cavity prevention techniques in school-based dental programs. One technique is a more complex treatment similar to the combined primary and secondary prevention, but the Bronx and New Hampshire studies will also introduce the use of silver diamine fluoride, a non-invasive, cavity-fighting liquid that is painted onto teeth to halt the progression of tooth decay. The cavity prevention programs will begin in schools in the fall of 2018.

People with diabetes visit the dentist less frequently despite link between diabetes, oral health

Adults with diabetes are less likely to visit the dentist than people with prediabetes or without diabetes, finds a new study led by researchers at NYU Rory Meyers College of Nursing and East Carolina University's Brody School of Medicine.

The study, published in The Journal of the American Dental Association, showed an overall decline in dental visits among adults with and without diabetes, but people with diabetes were consistently the least likely to obtain oral healthcare.

Research has shown a two-way relationship between diabetes and oral health. People with diabetes are at an increased risk for periodontal disease, a chronic inflammation of the gums and surrounding tissue and bone, while periodontal disease has an adverse effect on blood glucose control - which can contribute to the progression of diabetes. In fact, periodontal disease has been called the "sixth complication" of diabetes after issues like kidney disease, damage to the retina, and heart disease.

"For people living with diabetes, regular dental check-ups - paired with proactive dental and diabetes self-care - are important for maintaining good oral health. Regular dental visits provide opportunities for prevention, early detection, and treatment of periodontal disease, which can potentially help with blood glucose control and preventing complications from diabetes," said Bei Wu, PhD, Dean's Professor in Global Health and director of Global Health & Aging Research at NYU Meyers and the study's senior author.

Older studies have shown that individuals with diabetes had fewer dental visits than those without diabetes. In order to have an updated understanding of dental visits among people with diabetes, this study assessed the trends of annual dental visits from 2004 to 2014 in adults with diabetes, prediabetes, and without diabetes, and assessed racial and ethnic disparities in dental visits.

The researchers used data from the Behavioral Risk Factor Surveillance System, an annual telephone survey of U.S. adults during which respondents are asked whether or not they had a dental visit in the past 12 months and whether they were ever diagnosed with diabetes or prediabetes. The study sample included 2.5 million adults age 21 years and older, including 248,203 people with diabetes, 30,520 with prediabetes, and 2,221,534 without diabetes.

The researchers found that people with diabetes were the least likely to visit the dentist, followed by people with prediabetes. From 2004 to 2014, the proportion of annual dental visits declined from 66.1 percent to 61.4 percent among people with diabetes, 66 percent to 64.9 percent among people with prediabetes, and 71.9 percent to 66.5 percent among people without diabetes.

"This pattern is concerning, given that timely dental care is essential for good oral health, especially in individuals with diabetes. Those who need dental care the most seem to be the least likely to have it," said study author Huabin Luo, PhD, of East Carolina University.

Several factors may account for the underutilization of dental services by people with diabetes, according to the researchers. People may not be aware of the impact of diabetes on their oral health and vice versa. In addition, in a previous study, individuals with diabetes more frequently reported the cost of dental care as a reason for avoiding routine visits.

The researchers also observed racial and ethnic disparities in dental care. Black and Hispanic individuals were less likely to visit the dentist than were white people, and these disparities persisted over the decade studied. Males and single people were also less likely to regularly visit the dentist than females and married people.

While the study did not measure whether individuals had dental insurance, the researchers found substantial financial barriers to dental services for people with diabetes based comparing dental visits and income levels. The researchers assert that reducing these barriers and improving access to dental providers is needed, especially among people with diabetes and prediabetes.

"Healthcare providers and public health professionals should promote oral health in diabetes management and encourage people with diabetes to visit a dentist at least annually. Increasing access to dental services is vital to achieving this goal," said Wu, who is also co-director of the NYU Aging Incubator.