Recreational cannabis, used often, increases risk of gum disease

Columbia University dental researchers have found that frequent recreational use of cannabis--including marijuana, hashish, and hash oil--increases the risk of gum disease.

The study was published in the March issue of the Journal of Periodontology.

Periodontal (gum) disease is an inflammatory reaction to a bacterial infection below the gum line. Left untreated, gum disease can lead to receding gums and tooth loss. Longstanding periodontal disease has also been associated with a number of non-oral health issues, from preterm labor during pregnancy to heart disease.

Jaffer Shariff, DDS, MPH, a postdoctoral resident in periodontology at Columbia University School of Dental Medicine (CDM) and lead author, noticed a possible link between frequent recreational cannabis use and gum disease during his residency at a community-based dental clinic in Manhattan.

"It is well known that frequent tobacco use can increase the risk of periodontal disease, but it was surprising to see that recreational cannabis users may also be at risk," said Dr. Shariff. "The recent spate of new recreational and medical marijuana laws could spell the beginning of a growing oral public health problem."

Dr. Shariff and colleagues from CDM analyzed data from 1,938 U.S. adults who participated in the Centers for Disease Control's 2011-2012 National Health and Nutrition Examination Survey, administered in collaboration with the American Academy of Periodontology. Approximately 27 percent of the participants reported using cannabis one or more times for at least 12 months.

Periodontal exams focus on a patient's gum tissue and connection to the teeth. Among other assessments, periodontists look for plaque, inflammation, bleeding, and gum recession. The clinician uses a probe to measure the space between teeth and their surrounding gum tissue. 

Healthy gums fit a tooth snugly, with no more than one to three millimeters of space, known as pocket depth, between the tooth and surrounding gum tissue. Deeper pockets usually indicate presence of periodontitis. 

Among the study participants, frequent recreational cannabis users had more sites with pocket depths indicative of moderate to severe periodontal disease than less frequent users.

"Even controlling for other factors linked to gum disease, such as cigarette smoking, frequent recreational cannabis smokers are twice as likely as non-frequent users to have signs of periodontal disease," said Dr. Shariff. "While more research is needed to determine if medical marijuana has a similar impact on oral health, our study findings suggest that dental care providers should ask their patients about cannabis habits."

Commenting on the study, Dr. Terrence J. Griffin, president of the American Academy of Periodontology, said, "At a time when the legalization of recreational and medical marijuana is increasing its use in the United States, users should be made aware of the impact that any form of cannabis can have on the health of their gums."

Dentists in good compliance with American Heart Association guidelines, according to Rochester epidemiology project

In the first study examining dental records in the Rochester Epidemiology Project, results show that dentists and oral surgeons are in good compliance with guidelines issued by the American Heart Association (AHA) in 2007, describing prophylactic antibiotic use prior to invasive dental procedures.

The Rochester Epidemiology Project is a collaboration of medical and dental care providers in Minnesota and Wisconsin. With patient agreement, the organizations link medical, dental, surgical procedures, prescriptions, and other health care data for medical research.

Prior to 2007, the AHA guidelines recommended prophylactic antibiotics for patients with cardiac conditions who were at moderate or high risk of developing infective endocarditis -- a potentially deadly infection of the heart valve. After 2007, AHA recommended that only high-risk patients receive the antibiotics. This group represents a very small fraction of the individuals receiving antibiotics before 2007, says Daniel DeSimone, M.D., study lead author and infectious diseases and hospital internal medicine physician at Mayo Clinic. The study will be released May 23 online in Mayo Clinic Proceedings.

Earlier studies by Dr. DeSimone's team determined the incidence of infective endocarditis in Olmsted County before and after 2007, using Rochester Epidemiology Project data. They found no significant increase in cases of infective endocarditis following the introduction of updated AHA guidelines.

However, "the major limitation of these studies was the lack of access to dental records," says Dr. DeSimone.

"The inclusion of dental records in the Rochester Epidemiology Project provides a unique opportunity unlike any population health database in the United States," he says.

"The primary criticism of the earlier studies was, 'Are dentists actually following the 2007 AHA guidelines, or do patients continue to receive antibiotics when no longer indicated?'" reports Dr. DeSimone. "How could we prove that dentists were actually following the guidelines, rather than assuming they were? Now we can."

Dr. DeSimone also says, there are a number of health risks for patients when taking antibiotics. "Plus overuse of antibiotics can result in increased bacterial resistance, which is a widespread public health problem," he says.

In addition, while the cost to patients might only be a few dollars a dose, Dr. DeSimone says that when added up, this group of moderate-risk patients could spend well over $100 million per year.

"Using the Rochester Epidemiology Project, we have shown that the new guidelines were very helpful in reducing unnecessary antibiotic use and related issues, without an increase in new cases of infective endocarditis."

Although this was the first study using the newly linked dental records, it was just one of more than 2,600 medical research publications using the Rochester Epidemiology Project. Using medical and dental records, researchers can identify what causes diseases and how patients with certain diseases respond to surgery, medication or other interventions. They also can determine what the future holds for patients with specific diseases or medical conditions.

Extra weight may increase dental risks

Being overweight or obese was linked with an increased likelihood of having poor oral health in a recent study.

In the study of 160 participants, those with BMI ?23 had generally more severe periodontitis, total inflammatory dental diseases, and leukocyte counts than normal weight individuals. Patients who were obese (BMI ?25) had almost a 6-times increased risk for severe periodontitis compared with normal weight participants. Altered inflammatory molecules that are associated with obesity may play a role.

The results are published in Oral Diseases.

Grape seed extract could extend life of resin fillings

A natural compound found in grape seed extract could be used to strengthen dentin -- the tissue beneath a tooth's enamel -- and increase the life of resin fillings, according to new research at the University of Illinois at Chicago College of Dentistry.

No filling lasts forever, whether it's composite-resin or amalgam. But dentists find amalgam -- a combination of mercury, silver, tin or other materials -- easier to use and less costly. Plus, it can last 10 to 15 years or more. Composite-resin fillings are more aesthetically pleasing because the mixture of plastic and fine glass particles can be colored to match a patient's teeth. However, the fillings typically last only five to seven years.

In research published in the Journal of Dental Research, Ana Bedran-Russo, associate professor of restorative dentistry, describes how grape seed extract can make composite-resin fillings stronger, allowing them to last longer. The extract, Bedran-Russo said, can increase the strength of the dentin, which comprises the majority of the calcified extracellular tissue of teeth, forming the layer just beneath the hard external enamel.

Dentin is mostly made of collagen, the main structural protein in skin and other connective tissues. Resins have to bind to the dentin, but the area between the two, or the interface, is a weak point, causing restorations to breakdown, Bedran-Russo said.

"When fillings fail, decay forms around it and the seal is lost. We want to reinforce the interface, which will make the resin bond better to the dentin," she said. "The interface can be changed through the use of new natural materials."

More than 90 percent of adults between the ages of 20 and 64 have cavities, according to a federal report. A cavity is a hole that forms in the tooth when acid produced by bacteria erodes the minerals faster than the tooth can repair itself. The dentist removes the decay, or caries, with a drill and seals the hole with a filling.

Secondary caries and margin breakdown are the most frequent causes of failed adhesive restorations, Bedran-Russo said. Despite numerous advances in dental restorative materials, degradation of the adhesive interface still occurs.

Bedran-Russo has discovered that damaged collagen can repair itself with a combination of plant-based oligomeric proanthocyanidins -- flavonoids found in most foods and vegetables -- and extracts from grape seeds. Interlocking the resin and collagen-rich dentin provides better adhesion and does not rely on moisture.

"The stability of the interface is key for the durability of such adhesive joints, and hence, the life of the restoration and minimizing tooth loss," Bedran-Russo said.

One of the possible benefits of using grape seed extract is that it prevents tooth decay, she said. She and Guido Pauli, professor of medicinal chemistry and pharmacognosy in the UIC College of Pharmacy, recently collaborated on another study that showed extract from the root bark of Chinese red pine trees has similar properties to the grape seed extract.