Treating gum disease after heart rhythm ablation reduced risk of AFib recurrence

Research Highlights:

• Treating gum disease within three months after a heart procedure to correct an irregular heart rhythm, known as atrial fibrillation (AFib), may lower the chances of it reoccurring.
• Inflamed gums may predict AFib recurrence after heart ablation, a procedure to fix the irregular heartbeat.
• AFib patients should be examined for gum disease and encouraged to seek dental treatment, researchers said.

Treating gum disease in the 3-months after a procedure to correct an irregular heartbeat known as atrial fibrillation (AFib) may lower oral inflammation and may reduce AFib recurrence, according to new research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.

According to the U.S. Centers for Disease Control and Prevention (CDC), about half of American adults ages 30 or older have some form of periodontal or gum disease, with the incidence increasing with age.

This study is among the first to investigate the potential impact of gum disease treatment on AFib. AFib is a condition in which the heart beats irregularly, increasing the risk of stroke by five-fold. More than 12 million people in the U.S. are expected to have AFib by 2030, according to the American Heart Association’s 2024 Heart Disease and Stroke Statistics.

“Gum disease can be modified by dental intervention. Proper management of gum disease appears to improve the prognosis of AFib, and many people around the world could benefit from it,” said lead study author Shunsuke Miyauchi, M.D., Ph.D., an assistant professor at the Health Service Center at Hiroshima University in Japan who engages in general cardiology, arrhythmia practice and research.

Researchers followed 97 patients who had undergone the non-surgical procedure to correct AFib (radiofrequency catheter ablation) and received treatment for gum inflammation along with 191 ablation patients who did not receive treatment for gum disease. Catheter ablation is a procedure that uses radiofrequency energy to destroy a small area of heart tissue causing rapid and irregular heartbeats. This study found that an index measuring the severity of gum inflammation was associated with the return of AFib.

After the ablation procedure, during the average follow-up period of between 8.5 months to 2 years, researchers found:

• AFib recurred among 24% of all participants  throughout the follow-up period.
• Patients with severe gum inflammation who had it treated after heart catheter ablation were 61% less likely to have a recurrence of AFib, compared to ablation patients who did not have treatment for severe gum inflammation.
• Patients who had recurrences of AFib had more severe gum disease than those who did not have recurrences.
• Having gum disease, being female, experiencing irregular heartbeat for more than two years and left atrial volume were predictors for AFib recurrences. Left atrial volume often leads to AFib recurrence as it includes thickening and scarring of connective tissues, Miyauchi explained.

Miyauchi noted that, “While the main findings were consistent with their expectations, we were surprised how useful a quantitative index of gum disease, known as periodontal inflamed surface area or PISA, could be in cardiovascular clinical practice.”

While the American Heart Association does not recognize oral health as a risk factor for heart disease, it recognizes that oral health can be an indicator of overall health and well-being. Bacteria from inflamed teeth and gums may travel through the bloodstream to the rest of the body, including the heart and brain. Chronic gum inflammation may be associated with other systemic health conditions, including coronary artery disease, stroke and Type 2 diabetes.

Study details and background:

• A total of 288 adults (66% men; 34% women) being treated for AFib were enrolled in this study.
• The single center study was conducted from April 1, 2020 to July 31, 2022, at Hiroshima University Hospital in Hiroshima, Japan, and all participants were Asian.
• Enrollees were examined by a dentist before undergoing catheter ablation for AFib.

“We are now working on further research to reveal the mechanism underlying the relationship between gum disease and AFib,” Miyauchi said.

The study’s limitations include: a small number of patients enrolled from a single center; patients were not randomized to receive dental treatment; periodontal status was not followed up after the initial examination among the participants who did not receive gum disease treatment; and inflammatory markers were not reassessed after the ablation procedure.

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• AHA news release: New initiative focuses on oral health clinicians in prevention and early detection of heart disease (Jan. 2024)
• AHA news release: Poor oral health may contribute to declines in brain health (Feb 2022)
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ChatGPT to help dental students retain knowledge and enhance performance

 I

A study aiming to utilize current dental course materials, syllabi, and textbooks to investigate ChatGPT's potential benefits for dental students. was presented at the 102nd General Session of the IADR, which was held in conjunction with the 53rd Annual Meeting of the American Association for Dental, Oral, and Craniofacial Research and the 48th Annual Meeting of the Canadian Association for Dental Research, on March 13-16, 2024, in New Orleans, LA, USA.

The abstract, “ChatGPT to Help Dental Students Retain Knowledge and Enhance Performance” was presented during the “SCADA: Clinical Science/Public Health Research” Poster Session that took place on Thursday, March 14, 2024 at 11 a.m. Central Standard Time (UTC-6).

The study, by Ihunna Amugo of Meharry Medical College, Nashville, TN, USA, conducted an extensive literature review, analyzing previous studies in different educational contexts to evaluate ChatGPT's efficacy in dental education. Questions aligned with dental course materials and objectives were formulated to ensure ChatGPT's relevance to the specific needs of dental students. The research encompassed various dental courses, including operative dentistry, nutrition, periodontics, oral radiology, and biology of disease.

By applying ChatGPT in these courses, its capabilities were harnessed to generate step-by-step instructions, summaries, and questions to supplement traditional learning methods. Data on students' interactions with ChatGPT were collected and analyzed, assessing usage patterns, engagement levels, and perceived benefits. 

The study's results indicated that ChatGPT has the potential to enhance students' understanding and knowledge retention. In addition, ChatGPT can effectively provide instructional support and generate relevant content for dental students. 

Low-cost liquid tames tooth decay

An inexpensive, cavity-fighting liquid called silver diamine fluoride (SDF) works as well as dental sealants to keep tooth decay at bay in a school cavity prevention and treatment program, according to a new study by researchers at NYU College of Dentistry. 

 

The study, which followed more than 4,000 elementary school students for four years and is published in JAMA Pediatrics, shows that SDF is an effective alternative to sealants, and can increase access to dental care while reducing costs.

 

Dental cavities are the most prevalent chronic disease in children and can lead to pain, school absences, and lower academic performance. To prevent cavities, especially among children less likely to see a dentist, the Centers for Disease Control and Prevention (CDC) supports the use of school sealant programs. In sealant programs, dental professionals visit schools to apply a thin, protective coating to the surface of teeth that hardens and safeguards against decay.

 

SDF has emerged as another promising treatment for fighting cavities. Originally approved by the FDA for treating tooth sensitivity, the solution is brushed onto the surface of teeth, killing decay-causing bacteria and remineralizing teeth to prevent further decay.

 

“A growing body of research shows that SDF—which is quicker to apply and less expensive than sealants—can prevent and arrest cavities, reducing the need for drilling and filling,” said Richard Niederman, DMD, professor of epidemiology & health promotion at NYU College of Dentistry and the study’s senior author.

 

SDF in schools

Researchers at NYU College of Dentistry led CariedAway, the nation’s largest school-based cavity prevention study, to compare the use of SDF and traditional sealants. The study included approximately 4,100 children in New York City elementary schools; more than a quarter of kids had untreated cavities at the start of the study.

 

At each school visit, a team of health professionals examined children’s teeth and applied either sealants or SDF followed by fluoride varnish, depending on which treatment the school was randomly assigned to receive. Sealants were administered by dental hygienists, while SDF was applied by either dental hygienists or registered nurses, all under the supervision of a dentist. Starting in 2018, the team visited each school twice a year, although the COVID-19 pandemic and school closures led to missed visits.

 

The researchers reported last year in the journal JAMA Network Open that a single treatment of either SDF or sealants prevented 80% of cavities and kept 50% of existing cavities from worsening two years later. The team continued their study for another two years, and in their study published in JAMA Pediatrics, found that SDF and sealants prevented roughly the same number of cavities after children were followed for a total of four years. Moreover, both sealants and SDF reduced the risk of decay at each follow-up visit.

 

“Our longitudinal study reaffirms that both sealants and SDF are effective against cavities. SDF is a promising alternative that can support school-based cavity prevention—not to replace the dental sealant model, but as another option that also prevents and arrests decay,” said Ryan Richard Ruff, PhD, MPH, associate professor of epidemiology & health promotion at NYU College of Dentistry and the study’s first author.

 

“Most research shows that SDF can stop a cavity from progressing further. Our study demonstrated that SDF can prevent cavities from happening in the first place,” said Tamarinda Barry Godín, DDS, MPH, associate program director and supervising dentist for CariedAway, research scientist at NYU College of Dentistry, and the study’s coauthor. 

 

An “untapped” oral health workforce

Embracing SDF for cavity prevention and treatment in schools could keep kids from needing fillings, saving families and the healthcare system money. Yet these programs can only succeed if there are enough health professionals to provide care.

 

The NYU researchers found that children who had SDF applied by dental hygienists and registered nurses had similar outcomes, suggesting that nurses—including school nurses—could play a crucial role in cavity prevention programs. 

 

“Nurses may be an untapped resource for addressing oral health inequities,” added Ruff. “Our results suggest that nurses can effectively provide this preventive care, which could dramatically improve access, given the role of school nurses and the size of the nursing workforce.”

Those who report having poor oral health have negative long-term health outcomes

Those who report having poor oral health are as likely to have negative long-term systemic health outcomes as those previously diagnosed with periodontal disease, or gum disease, according to a new Tufts University School of Dental Medicine study published in The Journal of the American Dental Association. 

The researchers examined whether self-reported oral health questions, which are commonly used in the surveillance of periodontal disease, had the same or similar comorbidities of the disease by analyzing data sets from the Women’s Health Study and the National Health and Nutrition Examination Survey (NHANES). The Women’s Health Study followed women 45 years or older with self-reported information on gum disease, oral health questions, cardiovascular disease, diabetes, and osteoporosis in various timeframes starting from 1992, while the NHANES included data on oral health questions and linked mortality from 1999 to 2018. 

Led by first author Yau-Hua Yu, associate professor of periodontology at the School of Dental Medicine, the researchers tested their hypotheses by running analyses that estimated the probability of outcomes based on a variety of factors and then looked at survival rates within various groups. The results showed that negative self-evaluations were associated with the same level of systemic comorbidities as those who had been diagnosed with periodontal disease. The study also found that suboptimal dental visits or infrequent flossing were associated with an increase in all-cause mortality.  

“These questions are really helpful to understand a person’s oral health conditions when clinical access is limited,” said Yu, noting that in large epidemiological studies like the Women’s Health Study, it’s not possible to have a dentist on-site to physically examine research participants.

Yu and fellow researchers, including senior author Julie Buring of Brigham and Women’s Hospital and Harvard Medical School, also examined the role that access to dental care plays on overall health. They did this by asking two important questions: “In the past 12 months, have you visited the dentist or hygienist?” and “How often do you visit a dental office for routine check-ups and cleaning?” The researchers found that about 10% of the Women’s Health Study participants and 45% of NHANES study participants did not visit a dentist within a year and, as a result, their oral and overall health outcomes were poor.  

“Our study findings suggest that people who don’t see a dentist may have negative outcomes in terms of mortality,” Yu said, noting that their original goal was to understand the usefulness of these questions for understanding and evaluating gum disease and oral health in general.

Given this demonstrated link between oral health and mortality, Yu suggests primary care physicians consider asking about their patients’ dental habits and condition to get a fuller picture of their overall health.

Yu isn’t stopping with this study. She says she’s still working on big data sets, and hopes to showcase outcomes in different populations, such as veterans. She is currently collaborating with the U.S. Department of Veterans Affairs. 

And, Yu underscores the need for more large-scale national health studies/biobanking efforts to incorporate questions around dental health to better understand and communicate the association between oral health and long-term health outcomes, as well as the gaps in access to dental care.  

“For society in general,” she said, “we need to look at, without dental care access, what is the burden?”

‘Artificial tongue’ detects and inactivates common mouth bacteria

 

Peer-Reviewed Publication

AMERICAN CHEMICAL SOCIETY

From the fuzzy feeling on your teeth to the unfortunate condition of halitosis, bacteria shape mouth health. When dental illnesses take hold, diagnosis and treatment is necessary, but identifying the microorganisms behind an infection can be a lengthy and expensive process. Now, researchers reporting in ACS Applied Materials & Interfaces have designed a chemical sensor array, or an artificial tongue, that distinguishes dental bacteria and can inactivate them.

When bacteria are suspected as the agent behind dental disease, such as cavities or periodontitis, the first step is to identify the source. Traditional detection and identification methods can involve culturing or looking for specific DNA markers belonging to different species using sophisticated equipment. So, Na Lu, Zisheng Tang and coworkers wanted to investigate a simple and less expensive alternative: sensor arrays known as electronic or artificial tongues. Previously developed artificial tongues have detected and measured several types of bacteria, similar to how a real tongue can taste multiple flavors at once. And the researchers wanted to add in the capability of reducing the effects of, or inactivating, the identified dental bacteria.

The researchers turned to a nanoscopic particle that mimics natural enzymes, called a nanozyme, and made them from iron oxide particles coated in DNA strands. When hydrogen peroxide and a colorless indicator were added in solution, the presence of nanozymes caused the indicator to turn bright blue. However, bacteria that adhered to the DNA decreased the nanozyme’s reactivity, reducing the amount of blue color produced. The researchers coated nanozymes with different DNA strands so that each type of bacteria could be linked to a unique change in color signals. To test the DNA-nanozyme system, as an artificial tongue, the researchers created samples of 11 different dental bacteria species. The sensor array was able to identify all the bacteria in artificial saliva samples. Then, using the DNA-encoded nanozyme sensor array, the researchers were able to distinguish whether a dental plaque sample came from a healthy volunteer or from a person with cavities.

In addition, the DNA-encoded nanozyme sensor array had antibacterial effects on the dental bacteria species tested. Compared to controls without the nanozymes, three typical bacterial species were inactivated in solutions containing the nanozyme system. Scanning electronic microscopic images suggest to the researchers that the nanozyme system destroyed the bacteria membranes. They suggest that this sensor system could also be used in the future to diagnose and treat bacterial dental diseases.

When it comes to bad breath, some bacterial interactions really stink

 

Researchers from Osaka University find that a metabolite produced by the commensal oral bacterium Streptococcus gordonii activates another bacterial species, Fusobacterium nucleatum, to produce the malodorous compound methyl mercaptan

Peer-Reviewed Publication

OSAKA UNIVERSITY

 

IMAGE: 

SCHEMATIC REPRESENTATION OF OBSERVED METABOLIC FLOW OF BACTERIAL METABOLISM F. NUCLEATUM AND S. GORDONII COCULTURES.

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CREDIT: © 2024 HARA ET AL. THIS IS AN OPEN-ACCESS ARTICLE DISTRIBUTED UNDER THE TERMS OF THE CREATIVE COMMONS ATTRIBUTION 4.0 INTERNATIONAL LICENSE.

Osaka, Japan – Having bad breath really stinks! Now, researchers from Japan report that a particular combination of bacteria in our mouths may be responsible for producing some very unpleasant smells.

In a study published last month in mSystems, researchers from Osaka University revealed that the interaction between two common types of oral bacteria leads to the production of a chemical compound that is a major cause of smelly breath.

Bad breath is caused by volatile compounds that are produced when bacteria in the mouth digest substances like blood and food particles. One of the smelliest of these compounds is methyl mercaptan (CH3SH), which is produced by microbes that live around the teeth and on the surface of the tongue. However, little is known about which specific bacterial species are involved in this process.

“Most previous studies investigating CH3SH-producing oral bacteria have used isolated enzymes or relatively small culture volumes,” explains lead author of the study Takeshi Hara. “In this study, we aimed to create a more realistic environment in which to investigate CH3SH production by major oral bacteria.”

To do this, the researchers developed a large-volume anaerobic co-culture system that enabled them to test interactions between multiple different types of bacteria that live in the mouth. This system was able to test both direct, physical interactions among the bacteria, as well as whether these species could affect each other from a distance, for example by secreting active substances.

“The results were very intriguing,” says Masae Kuboniwa, senior author. “We found that Fusobacterium nucleatum produces large quantities of CH3SH in response to Streptococcus gordonii, another oral bacterium.”

By using stable isotope tracers and analyzing gene expression, the researchers showed that S. gordonii releases a substance called ornithine that prompts F. nucleatum to produce more of a molecule called polyamine. Because F. nucleatum needs methionine to produce polyamine, this enhanced polyamine production activates its methionine salvage pathway, which in turn results in increased CH3SH production.

“Taken together, these findings suggest that CH3SH production in the mouth is driven by the interaction between S. gordonii and F. nucleatum,” says Hara.

Understanding how these two bacterial species work together to cause bad breath could be helpful in developing ways to treat or even prevent bad breath. In addition, given that bad breath is often associated with periodontal disease, treating this symptom early could help prevent more serious damage in the future.

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The article, “Interspecies metabolite transfer fuels methionine metabolism of Fusobacterium nucleatum to stimulate volatile methyl mercaptan production,” was published in mSystems at DOI: https://doi.org/10.1128/msystems.00764-23

Gargling away the bad bacteria in type 2 diabetes

 

Researchers from Osaka University find that gargling with an antiseptic mouthwash can reduce ‘bad’ bacteria in the mouths of people with type 2 diabetes, and may lead to better control of their blood sugar

Peer-Reviewed Publication

OSAKA UNIVERSITY

 

IMAGE: 

MECHANISM OF TYPE 2 DIABETES MELLITUS IMPROVEMENT BY GARGLING WITH MOUTHWASH

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CREDIT: SAAYA MATAYOSHI

Osaka, Japan – More than bad breath, there is growing evidence that ongoing inflammation in the mouth, like with gum disease, is associated with serious diseases such as Alzheimer’s disease or type 2 diabetes. Now, researchers from Osaka University have identified an easy way to fight bacteria that might cause such problems.

In a study published this month in Scientific Reports, the researchers reported that when people with type 2 diabetes gargled with an antiseptic mouthwash, the numbers of periodontitis-related bacteria decreased. Excitingly, some patients with reduced bacteria also achieved much better control of their blood sugar, hinting at promising future clinical applications. 

“There are three highly virulent bacterial species that are linked to periodontitis, or diseases of the tissues surrounding the teeth,” explains lead author of the study Saaya Matayoshi. “We decided to see if we could reduce these three species—Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia—in patients with type 2 diabetes using a mouthwash containing the antiseptic chlorhexidine gluconate.”

To do this, the researchers took monthly or bimonthly saliva and blood samples from 173 patients over an entire year. With the saliva, the researchers noted the presence or absence of the three bacterial species, and with the blood samples, they measured HbA1c levels as a marker of blood-sugar control. Importantly, for the first 6 months of the study, the patients gargled with water, whereas for the second 6 months they gargled with the antiseptic mouthwash. In this way, the research team could see whether gargling itself was effective for reducing bacteria, or whether mouthwash was more effective.

“We were unsurprised to see that gargling with water had no effects on bacterial species or HbA1c levels,” explains Kazuhiko Nakano, senior author of the study. “However, there was an overall reduction in bacterial species when the patients switched to mouthwash, as long as they were gargling at least twice a day.”

The researchers also found that, although there were no overall changes in HbA1c levels when patients gargled with the antiseptic mouthwash, there appeared to be large variations in individual responses. For example, when they split the group into younger and older patients, younger patients had greater reductions in bacterial species and significantly better blood-sugar control with the mouthwash compared with water.

Given that poor oral health is linked to serious disease, simple methods to improve oral hygiene have important ramifications. If researchers can identify patients who are likely to respond well to antiseptic mouthwash, this easy-to-use treatment may improve the lives of people with periodontitis-linked diseases such as diabetes, dementia, cardiovascular disease, and respiratory tract infections.

 

New guideline details acute pain management strategies for adolescent, adult dental patients

Nonsteroidal anti-inflammatory drugs (NSAIDs) taken alone or along with acetaminophen are recommended as first-line treatments for managing short-term dental pain in adults and adolescents aged 12 or older, according to a new clinical practice guideline developed by the American Dental Association (ADA), the University of Pittsburgh School of Dental Medicine and the Center for Integrative Global Oral Health at the University of Pennsylvania School of Dental Medicine. The guideline has been endorsed by the ADA and is now available in the February issue of The Journal of the American Dental Association.

Based on review of the available evidence, a guideline panel concluded that, when used as directed, NSAIDs (like ibuprofen and naproxen) alone or in combination with acetaminophen can effectively manage pain after having a tooth removed or when experiencing a toothache when dental care is not immediately available.

The guideline also offers clinicians recommendations for prescribing opioid medications in the limited circumstances in which they may be appropriate. These include avoiding “just in case” prescriptions, engaging patients in shared decision-making and exerting extreme caution when prescribing opioids to adolescents and young adults. When prescribing opioids, the guideline suggests advising patients on proper storage and disposal and considering any risk factors for opioid misuse and serious adverse events.

“It’s important to take special consideration when prescribing any type of pain reliever, and now, dentists have a set of evidence-based recommendations to determine the best care for their patients,” said Dr. Paul Moore, D.M.D., Ph.D., M.P.H., the guideline’s senior author and panel chair and professor emeritus at the University of Pittsburgh’s School of Dental Medicine. “Patients are encouraged to discuss pain management expectations and strategies with their dentist so they can feel confident that they are receiving the safest, most effective treatment for their symptoms.”

In 2020, the U.S. Food and Drug Administration (FDA) awarded the University of Pittsburgh and the ADA Science & Research Institute (ADASRI) – now the ADA Forsyth Institute – a three-year $1.5 million grant to develop a clinical practice guideline for the management of acute pain in dentistry in children, adolescents and adults. A group of researchers and methodologists from ADASRI, University of Pittsburgh School of Dental Medicine, Center for Integrative Global Oral Health at the University of Pennsylvania School of Dental Medicine, McMaster University and The Art of Democracy worked together to develop the guideline.

“Providing prescribing guidelines for acute dental pain management is an important step towards improving patient treatment and outcomes,” said Dr. Marta Sokolowska, Ph.D., deputy center director for substance use and behavioral health at the FDA's Center for Drug Evaluation and Research. “We hope this clinical practice guideline will reduce the risk of opioid addiction, overdose and diversion.”

This is the second of two guidelines on acute dental pain management. A previous set of recommendations for pediatric patients was published in 2023. Both guidelines can be found at ada.org/painmanagement.

For more information on how the ADA is working to combat opioid misuse while continuing to help patients manage dental pain, visit ada.org/opioids.

The contents of the guidelines are those of the author(s) and do not necessarily represent the official views of, nor an endorsement by, the FDA, U.S. Department of Health and Human Services or U.S. government.
 

ADA releases updated recommendations to enhance radiography safety in dentistry

 

 The use of lead abdominal aprons or thyroid collars on patients when conducting dental X-rays is no longer recommended, according to an expert panel established by the American Dental Association (ADA) Council on Scientific Affairs. Additionally, dentists should take into consideration the diagnostic information needed from X-rays to benefit patient care or substantially improve clinical outcomes.

The Journal of the American Dental Association published the new recommendations today, which aim to improve radiation protection in dental radiography and cone-beam computed tomography (CBCT). Medical physicists with the U.S. Food and Drug Administration (FDA) supported the panel’s development of these recommendations – the first on dental imaging safety and radiation protection from the Council since 2012. The Council’s recommendations are also aligned with recent recommendations released by the American Academy of Oral and Maxillofacial Radiology.

After reviewing published studies on radiography, the expert panel determined lead aprons and thyroid collars are not necessary to shield patients from radiation exposure. These recommendations apply to all patients, regardless of age or health status (like pregnancy). Evidence indicates that modern digital X-ray equipment and restricting the beam size only to the area that needs to be imaged better protect patients against radiation exposure to other parts of their body. Lead aprons and thyroid collars can also block the primary X-ray beam, preventing dentists from capturing the image they need.

“When this happens, more radiographs need to be taken, and unnecessary X-rays are what we want to avoid,” said Dr. Purnima Kumar, D.D.S., Ph.D., professor of dentistry and chair of the Department of Periodontology and Oral Medicine at the University of Michigan School of Dentistry and chair of the ADA Council on Scientific Affairs. “The central point of these recommendations is that clinicians should order radiographs in moderation to minimize both patients’ and dental professionals’ exposure to ionizing radiation.”

The recommendations also advise dentists to safeguard patients against unnecessary radiation exposure by:

• Ordering radiographs like X-rays to optimize diagnostic information and enhance patient care outcomes and making every effort to use images acquired at previous dental exams;
• Using digital instead of conventional X-ray film for imaging;
• Restricting the beam size during an X-ray exam to the area that needs to be assessed (an approach called “rectangular collimation”);
• Properly positioning patients so the best image can be taken;
• Incorporating CBCT only when lower-exposure options will not provide the necessary diagnostic information; and
• Adhering to all applicable federal, state and local regulations on radiation safety.

“We encourage dentists and their teams to review these best-practice recommendations, comply with radiation protection regulations and talk with their patients about any questions or concerns before ordering dental imaging,” Dr. Kumar said.

To view the complete recommendations, visit JADA.ada.org.

Brush biopsy enables early detection of oral cancer without surgery

 

Reports and Proceedings

UNIVERSITY OF ILLINOIS CHICAGO

A new test invented by University of Illinois Chicago researchers allows dentists to screen for the most common form of oral cancer with a simple and familiar tool: the brush. 

The diagnostic kit, created and patented by Guy Adami and Dr. Joel Schwartz of the UIC College of Dentistry, uses a small brush to collect cells from potentially cancerous lesions inside the mouth. The sample is then analyzed for genetic signals of oral squamous cell carcinoma, the ninth most prevalent cancer globally. 

This new screening method, which is currently seeking commercialization partnerships, improves upon the current diagnostic standard of surgical biopsies — an extra referral step that risks losing patients who sometimes don’t return until the cancer progresses to more advanced, hard-to-treat stages.  

“So many patients get lost; they don’t follow up,” said Adami, associate professor of oral medicine and diagnostic sciences. “We’ve tried to keep our focus mainly on early Stage 1 and 2 cancers, so it actually works with the cancers that you want to detect.” 

The detection system works by looking for small segments of genetic material called microRNA that regulate the expression of genes. Research conducted by Adami and Schwartz found an expression signature of 40 microRNA sequences that can distinguish between a tumor and normal tissue with over 90% accuracy. 

Importantly, their test also worked using epithelial cells, the outermost layer of cells in a patient’s mouth. These cells can be easily collected in less than a minute of gentle brushing — no numbing required — by a dentist or nurse, who then places the brush in a tube of solution and sends it to a lab for microRNA analysis. Results can be returned to the clinic in days with the current version of the diagnostic test. 

“We were the first to observe that brush biopsy samples actually work quite well when you use microRNA,” Adami said. “All you need is a good light and the brushes.” 

In addition to the convenience of the collection method, the brush biopsy also provides several other advantages, the authors said. Surgical biopsies often collect a mixture of cell types, making subsequent analysis more complicated, and risk spreading cancerous cells to other areas of the mouth. And unlike blood tests that survey generally for genetic signals of cancer, the brush method only collects cells from a single site where treatment can be focused if a malignancy is detected. 

“If you compare what we do, which is site-specific targeting of tissue, to the other tests out there, they don’t have a targeting of where the tumors actually are,” said Schwartz, professor of oral medicine and diagnostic sciences. “That makes it harder to start treatment rapidly after detection.” 

The inventors hope that the new test will make screening easier to perform, particularly in patient populations that don’t receive regular dental care or have a higher incidence of oral squamous cell carcinoma. For example, Black men have a dramatically lower survival rate with the disease compared with white, Hispanic and Asian men. Usage of the invention in nonclinical settings would allow earlier cancer detection in high-risk populations.

The technology may also eventually be useful in diagnosing other oral diseases through their own unique microRNA signatures, the authors said. To commercialize the test, Adami and Schwartz formed a company called Arphion Diagnostics that has worked with the UIC Office of Technology Management. But they continue to look for business partners to help take the test into dental clinics. 

“There are 600 different diseases that occur in the mouth, and a number of these have already been characterized with microRNAs,” Schwartz said. “We could use the same approach and really have a profound impact on these kinds of disease.” 

In addition to Adami and Schwartz, research and design of the diagnostic test was conducted by oral and maxillofacial surgeon Dr. Antonia Kolokythas, a key member of the project who helped optimize the methodology and identified and collected brush samples from the first group of patients. The work was supported by grants from the National Science Foundation and the National Cancer Institute. Adami and Schwartz are also members of the University of Illinois Cancer Center.

How gum disease aggravates chronic obstructive pulmonary disease

 

Peer-Reviewed Publication

AMERICAN SOCIETY FOR MICROBIOLOGY

Highlights:

• Previous studies have connected severe gum disease to chronic obstructive pulmonary disease, or COPD.
• Bacteria play a critical role, but the details remain unclear.
• A new study shows how periodontitis, an oral disease, activates immune cells associated with aggravated progression of COPD.
• The findings suggest that periodontitis and COPD together worsen COPD, and point to gum disease management as a potential treatment for COPD.

Washington, D.C.—Severe gum disease has been linked to the progression of chronic obstructive pulmonary disease, or COPD, but an understanding of how the connection plays out in the immune system remains unclear. This week in mSystems, a new study identifies immune system cells that play a critical role in the microbial link between COPD and gum disease.

Researchers from Sichuan University, in China, report that bacteria associated with the gum disease promote COPD through the activation of 2 types of cells, γδ T cells and M2 macrophages, that are important to the immune system. Focusing on this mechanism might offer new, practical strategies for COPD prevention or control, said the researchers, from the West China Hospital of Stomatology at Sichuan University.

“By enhancing periodontal therapy and targeting the inhibition of γδ T cells and M2 macrophages [we] may be able to help control the progression of COPD,” said microbiologist Boyu Tang, Ph.D., who led the study with microbiologist Yan Li, Ph.D. 

According to the World Health Organization, COPD is the sixth-leading cause of death worldwide. It is not curable. In higher-income countries, tobacco smoking is the leading cause of COPD; in low- and middle-income countries, both tobacco smoking and household air pollution are significant risk factors. 

Periodontitis is a gum disease that results from the untreated buildup of plaque, a sticky film made primarily of bacteria. Over time, the plaque can harden into tartar and cause irritation and inflammation of gum tissue, and then produce deep gaps between the teeth and gums where bacteria flourish and may lead to bone loss. Periodontitis is a chronic infectious disease, and previous studies have found that it’s a risk factor for a raft of diseases, including diabetes, hypertension, some cancers, cardiovascular disease and COPD. 

Previous studies, including some led by Li and Tang, have established that the oral bacteria Porphyromonas gingivalis plays an important role in gum disease. For the new work, Li, Tang and their colleagues used mouse models to show how those bacteria could aggravate progression of COPD. In one experiment, they showed that mice infected with both periodontitis and COPD had worse progression of COPD than mice infected with COPD alone. 

In another experiment, they found that in mice orally infected with P. gingivalis, the bacteria migrated to and infected lung tissue, leading to a significant, observable change in the lung microbiota. Further observations using flow cytometry and immunofluorescence revealed that periodontitis promoted the expansion of the immune cells in the lung tissue. Finally, in experiments using mouse lung tissue, the group connected the dots by showing that P. gingivalis could activate the immune cells, promoting their ability to produce cytokines associated with worsening COPD.  

The researchers noted that the decrease in lung function and increase in immune cells was more modest than they’d predicted, but that could be an artifact of the experimental setup. The team created COPD animal models using exposure to cigarette smoke. “If the cigarette smoke exposure could be extended for a longer period of time, these changes might be more pronounced,” Li said. In future studies, Li said that the group plans to investigate how increases in smoke exposure might affect the immune response. 

“We’ll further carry out additional studies on human subjects to confirm the mechanism,” Li said. They plan to recruit patients with both conditions and offer periodontitis treatment, then compare lung function and immune cell counts before and after. “Our finding could lead to a potential new strategy for treating COPD.”