Study Examines Treatment Responses in TMD Patients

Tempromandibular pain disorders (TMDs) are characterized by a dysfunction of the TMD joint and cause orofacial pain, masticatory dysfunction or both. A new study published in The Journal of Pain showed that standard treatment approaches yield modest to large improvement in pain, but the addition of cognitive behavioral therapy may be helpful. The Journal of Pain is published by the American Pain Society, www.americanpainsociety.org.

Some 10 to 36 million U.S. adults, primarily women, have TMD pain, making this condition the second most frequent pain disorder following low-back pain. MD pain usually can be managed with conservative treatment with non-steroidal anti-inflammatory pain medications (NSAIDS), supportive patient education, diet modifications and an intraoral splint and/or occlusal therapy. Not all patients benefit, however, and previous research has shown that many TMD patients benefit from cognitive behavioral therapy (CBT). But the reasons behind CBT treatment success or failure are unclear.

Researchers from the University of Connecticut Health Center evaluated 101 TMD patients on a daily basis for three months. Study subjects reported having TMD pain for an average of 6.7 years. They were randomly assigned to one of two treatment groups: standard conservative care and standard care with CBT added, which included coping skills training. The purpose of the study was to determine if specific subtypes of treatment nonresponsive TMD patients could be identified to determine if CBT could be helpful.

The authors hypothesized that certain CBT treatment-related outcomes, such as lower retention in treatment and less adaptive changes in coping, self efficacy and catastrophizing, might be predictive of treatment non-response.

Results showed that nonresponders scored higher on depression scores, exhibited lower self efficacy and coping ability, and catastrophized more than more adaptive patients. It was noted that nonresponsive patients did not show more joint pathology than patients who responded well to treatment. Despite lack of joint pathology, the nonresponsive subjects were more likely to report being disabled by their TMD pain.

The study concluded it is important to recognize the importance of the heterogeneous nature of TMD pain, and that treating TMD patients as a homogeneous group is likely to result in suboptimal therapy for many patients. Even though no treatment is successful for all TMD patients, certain psychosocial factors can make some patients unresponsive to CBT.

Buck Teeth: Correct Them Once In Early Adolescence

Courtesy of Health Behavior News Service, part of the Center for Advancing Health

KEY POINTS

* A review finds few benefits to a two-stage orthodontic correction for buck teeth in children versus treatment done in one-stage during early adolescence.__* A two stage correction requires treatment over a longer period of time, which typically increases the cost.

Newswise — Children with prominent front teeth, colloquially known as buck teeth, often require orthodontic work to straighten their teeth and improve both their bite and appearance. This can be done in one stage during early adolescence (age 10 to 16) or two stages with the first stage between age 7 and 11 and the second in early adolescence. A new Cochrane review finds few benefits to the two-stage correction.

Upper front teeth that stick out are more likely to be broken or knocked out in an accident. In addition, their appearance can lead to a child being made fun of or being bullied. But orthodontists, parents, and children are faced with deciding whether to treat in two stages, early and late, or in just one later stage.

The research team analyzed data from 17 randomized controlled trials of children treated for Class II malocclusion, which is one cause of prominent front teeth. The trials included 721 children.

They concluded that providing treatment early slightly reduced the risk of a child damaging their front teeth if they had an accident while playing or participating in sports, but offered few other benefits. "There was no other benefit for having treatment early, age 8, as opposed to having treatment during adolescent age," according to Kevin O'Brien, professor of orthodontics at the University of Manchester in England.

"The results of this review will provide information to allow the orthodontist to explain fully the potential risks of not having treatment when the child is 8 years old," O'Brien stated. This can help orthodontists, parents and their children make an informed decision, he said.

The study also looked at evaluations of several types of orthodontic braces and appliances, including fixed and removable devices and head-braces. One type, the Twin-Block, was shown to be more effective in reducing the protrusion of the upper front teeth at an early age.

There is no official standard of care when it comes to treating prominent front teeth, David L. Turpin, D.D.S., Moore/Riedel Professor in the department of orthodontics at the University of Washington School of Dentistry in Seattle. "Teeth come in all types of bite and jaw relationships and children come in all shapes and sizes," he said. "Orthodontists should know all the different ramifications and should be good at treating problems in differing ways to meet the child's needs."

"In general, the earlier that treatment starts the longer it lasts, which in turn increases the cost," Turpin said.

TERMS OF USE: This story is protected by copyright. When reproducing any material, including interview excerpts, attribution to the Health Behavior News Service, part of the Center for Advancing Health,

Junk food and poor oral health increase risk of premature heart disease

The association between poor oral health and increased risk of cardiovascular disease should make the reduction of sugars such as those contained in junk food, particularly fizzy drinks, an important health policy target, say experts writing in the Journal of the Royal Society of Medicine. Poor oral hygiene and excess sugar consumption can lead to periodontal disease where the supporting bone around the teeth is destroyed. It is thought that chronic infection from gum disease can trigger an inflammatory response that leads to heart disease through a process called atherosclerosis, or hardening of the arteries. Despite convincing evidence linking poor oral health to premature heart disease, the most recent UK national guidance on the prevention of CVD at population level mentions the reduction of sugar only indirectly.

Dr Ahmed Rashid, Department of Public Health and Primary Care, University of Cambridge, who co-wrote the paper, said: "As well as having high levels of fats and salt, junk foods often contain a great deal of sugar and the effect this has on oral health may be an important additional mechanism by which junk food elevates risk of CVD." He added: "Among different types of junk food, soft drinks have raised particular concerns and are the main source of free sugar for many individuals." The authors refer to the well-publicised New York 'soda ban' controversy which has brought the issue to the attention of many. Yet, they point out, in the UK fizzy drinks remain commonly available in public areas ranging from hospitals to schools. Dr Rashid said: "The UK population should be encouraged to reduce fizzy drink intake and improve oral hygiene. Reducing sugar consumption and managing dental problems early could help prevent heart problems later in life."

Brushing your teeth could prevent heart disease

Prospective study finds clinically significant difference in atherosclerosis progression based on changes in periodontal health

Taking care of your gums by brushing, flossing, and regular dental visits could help hold heart disease at bay. Researchers at Columbia University's Mailman School of Public Health have shown for the first time that as gum health improves, progression of atherosclerosis slows to a clinically significant degree. Findings appear online in the Journal of the American Heart Association.

Artherosclerosis, or the narrowing of arteries through the build-up of plaque, is a major risk factor for heart disease, stroke, and death.

"These results are important because atherosclerosis progressed in parallel with both clinical periodontal disease and the bacterial profiles in the gums. This is the most direct evidence yet that modifying the periodontal bacterial profile could play a role in preventing or slowing both diseases," says Moïse Desvarieux, MD, PhD, lead author of the paper and associate professor of Epidemiology at the Mailman School.

The researchers followed 420 adults as part of the Oral Infections and Vascular Disease Epidemiology Study (INVEST), a randomly sampled prospective cohort of Northern Manhattan residents. Participants were examined for periodontal infection. Overall, 5,008 plaque samples were taken from several teeth, beneath the gum, and analyzed for 11 bacterial strains linked to periodontal disease and seven control bacteria. Fluid around the gums was sampled to assess levels of Interleukin-1β, a marker of inflammation. Atherosclerosis in both carotid arteries was measured using high-resolution ultrasound.

Over a median follow-up period of three years, the researchers found that improvement in periodontal health—health of the gums—and a reduction in the proportion of specific bacteria linked to periodontal disease correlated to a slower intima-medial thickness (IMT) progression, and worsening periodontal infections paralleled the progression of IMT. Results were adjusted for potential confounders such as body mass index, cholesterol levels, diabetes, and smoking status,

Clinical Significance

There was a 0.1 mm difference in IMT change over three years among study participants whose periodontal health was deteriorating compared with those whose periodontal health was improving. Previous research has shown that a .033 mm/year increase in carotid IMT (equivalent to approximately 0.1 mm over three years) is associated with a 2.3-fold increased risk for coronary events.

"When it comes to atherosclerosis, a tenth of a millimeter in the thickness of the carotid artery is a big deal. Based on prior research, it appears to meet the threshold of clinical significance," says Tatjana Rundek, MD, PhD, a co-author of the study and professor at the University of Miami whose lab read the carotid ultrasounds.

Even subtle changes to periodontal status had a dose-response relationship to carotid IMT. "Our results show a clear relationship between what is happening in the mouth and thickening of the carotid artery, even before the onset of full-fledged periodontal disease," says co-author Panos N. Papapanou, DDS, PhD, professor of Dental Medicine at Columbia University's College of Dental Medicine, whose laboratory assessed the bacterial profiles in the gums. "This suggests that incipient periodontal disease should not be ignored."

Bacteria in the mouth may contribute to the onset of atherosclerosis in a number of ways, scientists speculate. Animal studies indicate that they may trigger immune response and high levels of inflammatory markers, which may initiate or exacerbate the inflammatory aspect of atherosclerosis.

The results build on previous findings. In earlier cross-sectional results, Dr. Desvarieux and colleagues had reported that higher levels of disease-causing bacteria were associated with thicker IMT. The current study takes the next step by looking at the cohort over time.

"Our results address a gap identified in the AHA statement on periodontal disease and atherosclerosis, by providing longitudinal data supporting this association," says study co-author Ralph Sacco, MD, professor and chairman of Neurology at the University of Miami, Miller School of Medicine and former president of the American Heart Association. Concludes Dr. Desvarieux, "It is critical that we continue to follow these patients to see if the relationship between periodontal infections and atherosclerosis carries over to clinical events like heart attack and stroke and test if modifying the periodontal flora will slow the progression of atherosclerosis."

Burning Mouth Syndrome Is Often Difficult to Diagnose

Oral pain that feels like a scalded mouth and can last for months has baffled dental researchers since the 1970s, when burning oral sensations were linked to mucosal, periodontal, and restorative disorders and mental or emotional causes.

It’s called burning mouth syndrome (BMS), and it’s gaining the attention of such dental researchers as oral pain expert Andres Pinto, who recently joined Case Western Reserve University’s School of Dental Medicine faculty.

What’s frustrates patients and doctors alike, said Pinto, is that the mouth and gums appear normal with BMS, so its diagnosis is difficult. Patients often find themselves having to visit several doctors before finally arriving at BMS as the cause.

Pinto, new chair and associate professor in the Department of Oral Diagnosis and Radiology at the dental school and an oral medical specialist in the Department of Oral and Maxillofacial Surgery at UH Case Medical Center, encourages people with persistent mouth pain to check for the following symptoms that might be caused by BMS:

• Persistent burning tongue and oral pain with no apparent dental cause
• Abnormal taste or dry feeling in the mouth
• Symptoms that disappear when eating
• Burning sensations may migrate across several oral areas

Even if oral pain is present without these symptoms, Pinto recommended consulting a dentist for a thorough exam of the teeth, gums, mouth and throat.

Between two and five percent of the U.S. population acquires BMS, he said, but the syndrome especially strikes women between age 50 and 70, and from three years before to 12 years after menopause.

Early research in BMS explored the association with local oral changes that could be corrected by dentists, and the observed comorbidity with psychogenic disorders. Changes in neurologic sensory function in patients with BMS and reported cases of secondary BMS to anemia, diabetes, vitamin deficiency, and thyroid disorders, triggered further exploration into peripheral neural changes and central nervous system (brain) mechanisms that could contribute to the causes of this condition.

Although the exact cause of BMS is unknown, the suspected origin is deterioration of the nerves beneath the oral lining. The deterioration isn’t visible, which explains why the mouth appears normal when examined and can delay diagnosis, Pinto explained. Still unproven is the role hormones may play in BMS, given the link to menopause.

The pain from BMS often results in quality of life issues, from poor nutrition to the sufferer withdrawing from social situations. In some cases, the pain is so severe it has driven people to commit suicide, Pinto said.

Patients can receive relief with special mouthwashes, analgesics and other topical and systemic treatments.

Pinto recently joined a research team to learn what postgraduate programs in dental schools are teaching about BMS. The researchers report in the October issue of the Journal of the American Dental Association that BMS is being taught but more needs to be done.

Olympians say poor oral health is impairing performance

Many of the elite sportsmen and women who competed at the London 2012 Olympic Games had poor levels of oral health similar to those experienced by the most disadvantaged populations. 18 per cent of athletes surveyed said their oral health was having a negative impact on their performance.

The research, which was led by Professor Ian Needleman at the UCL Eastman Dental Institute, is published in the British Journal of Sports Medicine.

The researchers recruited 302 athletes to take part in the study at the Dental Clinic in the London 2012 athletes' village. The athletes represented 25 different sports, with 95 (34.9 per cent) competing in track and field, 38 (14 per cent) boxing and 31 (11.4 per cent) playing hockey. The athletes were given a systematic oral health check-up before being asked to give a personal assessment of the impact of oral health on their quality of life and athletic training/performance.

Overall, the research team found high levels of poor oral health with 55 per cent of athletes suffering from dental caries (tooth decay), of which 41 per cent was into the dentine (and therefore irreversible). More than three quarters of the participants had gingivitis (early stage gum disease) with 15 per cent showing signs of periodontitis, an irreversible gum infection in the soft tissue around the teeth.

42 per cent of athletes taking part in the study said that they were, "bothered by oral health" issues, with 28 per cent saying that it affected their quality of life. Almost one in five (18 per cent) athletes said that they believed poor oral health was negatively affecting their training or performance levels.

Nearly half of participants (46.5 per cent) had not attended for a dental examination or hygiene care in the previous year, while 8.7 per cent said they had never been to the dentist.

Professor Ian Needleman, lead author of the paper at the UCL Eastman Dental Institute, said: "Oral health is important for wellbeing and successful elite sporting performance. It is amazing that many professional athletes – people who dedicate a huge amount of time and energy to honing their physical abilities – do not have sufficient support for their oral health needs, even though this negatively impacts on their training and performance.

"Oral health assessment should be part of every athlete's routine medical care," continues Professor Needleman. "If we are going to help them optimise their level of performance we need to concentrate on oral health promotion and disease prevention strategies to facilitate the health and wellbeing of all our elite athletes."

In the report the authors speculate that the associations between oral health, wellbeing and performance might be explained by oral disease causing pain, systemic inflammation and a reduction in self-confidence and quality of life.

Previous studies have repeatedly found athletes to have poor oral health, something which might result from frequent carbohydrate intake, a reduced immune function through intensive training and a lack of awareness about the links between oral health and elite performance.

Are nanodiamond-encrusted teeth the future of dental implants?

UCLA researchers have discovered that diamonds on a much, much smaller scale than those used in jewelry could be used to promote bone growth and the durability of dental implants.

Nanodiamonds, which are created as byproducts of conventional mining and refining operations, are approximately four to five nanometers in diameter and are shaped like tiny soccer balls. Scientists from the UCLA School of Dentistry, the UCLA Department of Bioengineering and Northwestern University, along with collaborators at the NanoCarbon Research Institute in Japan, may have found a way to use them to improve bone growth and combat osteonecrosis, a potentially debilitating disease in which bones break down due to reduced blood flow.

When osteonecrosis affects the jaw, it can prevent people from eating and speaking; when it occurs near joints, it can restrict or preclude movement. Bone loss also occurs next to implants such as prosthetic joints or teeth, which leads to the implants becoming loose — or failing.

Implant failures necessitate additional procedures, which can be painful and expensive, and can jeopardize the function the patient had gained with an implant. These challenges are exacerbated when the disease occurs in the mouth, where there is a limited supply of local bone that can be used to secure the prosthetic tooth, a key consideration for both functional and aesthetic reasons.

The study, led by Dr. Dean Ho, professor of oral biology and medicine and co-director of the Jane and Jerry Weintraub Center for Reconstructive Biotechnology at the UCLA School of Dentistry, appears online in the peer-reviewed Journal of Dental Research.

During bone repair operations, which are typically costly and time-consuming, doctors insert a sponge through invasive surgery to locally administer proteins that promote bone growth, such as bone morphogenic protein.

Ho's team discovered that using nanodiamonds to deliver these proteins has the potential to be more effective than the conventional approaches. The study found that nanodiamonds, which are invisible to the human eye, bind rapidly to both bone morphogenetic protein and fibroblast growth factor, demonstrating that the proteins can be simultaneously delivered using one vehicle. The unique surface of the diamonds allows the proteins to be delivered more slowly, which may allow the affected area to be treated for a longer period of time. Furthermore, the nanodiamonds can be administered non-invasively, such as by an injection or an oral rinse.

"We've conducted several comprehensive studies, in both cells and animal models, looking at the safety of the nanodiamond particles," said Laura Moore, the first author of the study and an M.D.-Ph.D. student at Northwestern University under the mentorship of Dr. Ho. "Initial studies indicate that they are well tolerated, which further increases their potential in dental and bone repair applications."

"Nanodiamonds are versatile platforms," said Ho, who is also professor of bioengineering and a member of the Jonsson Comprehensive Cancer Center and the California NanoSystems Institute. "Because they are useful for delivering such a broad range of therapies, nanodiamonds have the potential to impact several other facets of oral, maxillofacial and orthopedic surgery, as well as regenerative medicine."

Ho's team previously showed that nanodiamonds in preclinical models were effective at treating multiple forms of cancer. Because osteonecrosis can be a side effect of chemotherapy, the group decided to examine whether nanodiamonds might help treat the bone loss as well. Results from the new study could open the door for this versatile material to be used to address multiple challenges in drug delivery, regenerative medicine and other fields.

"This discovery serves as a foundation for the future of nanotechnology in dentistry, orthopedics and other domains in medicine," said Dr. No-Hee Park, dean of the School of Dentistry. "Dr. Ho and his team have demonstrated the enormous potential of the nanodiamonds toward improving patient care. He is a pioneer in his field."

Bacteria responsible for gum disease facilitates development and progression of rheumatoid arthritis

Does gum disease indicate future joint problems? Although researchers and clinicians have long known about an association between two prevalent chronic inflammatory diseases - periodontal disease and rheumatoid arthritis (RA) - the microbiological mechanisms have remained unclear.

In an article published today in PLoS Pathogens, University of Louisville School of Dentistry Oral Health and Systemic Diseases group researcher Jan Potempa, PhD, DSc, and an international team of scientists from the European Union’s Gums and Joints project have uncovered how the bacterium responsible for periodontal disease, Porphyromonas gingivalis worsens RA by leading to earlier onset, faster progression and greater severity of the disease, including increased bone and cartilage destruction.

The scientists found that P. gingivalis produces a unique enzyme, peptidylarginine deiminanse (PAD) which then enhances collagen-induced arthritis (CIA), a form of arthritis similar to RA produced in the lab. PAD changes residues of certain proteins into citrulline, and the body recognizes citullinated proteins as intruders, leading to an immune attack. In RA patients, the subsequent result is chronic inflammation responsible for bone and cartilage destruction within the joints.

Potempa and his team studied another oral bacterium, Prevotella intermedia for the same affect, but learned it did not produce PAD, and did not affect CIA.

“Taken together, our results suggest that bacterial PAD may constitute the mechanistic link between P. gingivalis periodontal infection and rheumatoid arthritis, but this ground-breaking conclusion will need to be verified with further research,” he said.

Potempa said he is hopeful these findings will shed new light on the treatment and prevention of RA.

Studies indicate that compared to the general population, people with periodontal disease have an increased prevalence of RA and, periodontal disease is at least two times more prevalent in RA patients. Other research has shown that a P. gingivalis infection in the mouth will precede RA, and the bacterium is the likely culprit for onset and continuation of the autoimmune inflammatory responses that occur in the disease.

Expectant mothers' periodontal health vital to health of her baby

When a woman becomes pregnant, she knows it is important to maintain a healthy lifestyle to ensure both the health of herself and the health of her baby. New clinical recommendations from the American Academy of Periodontology (AAP) and the Eurpean Federation of Periodontology (EFP) urge pregnant women to maintain periodontal health as well. Research has indicated that women with periodontal disease may be at risk of adverse pregnancy outcomes, such giving birth to a pre-term or low-birth weight baby, reports the AAP and EFP.

Periodontal disease is a chronic, bacteria-induced, inflammatory condition that attacks the gum tissue and in more severe cases, the bone supporting the teeth. If left untreated, periodontal disease, also known as gum disease, can lead to tooth loss and has been associated with other systemic diseases, such as diabetes and cardiovascular disease.

"Tenderness, redness, or swollen gums are a few indications of periodontonal disease," warns Dr. Nancy L. Newhouse, DDS, MS, President of the AAP and a practicing periodontist in Independence, Missouri. "Other symptoms include gums that bleed with toothbrushing or eating, gums that are pulling away from the teeth, bad breath, and loose teeth. These signs, especially during pregnancy, should not be ignored and may require treatment from a dental professional."

Several research studies have suggested that women with periodontal disease may be more likely to deliver babies prematurely or with low-birth weight than mothers with healthy gums. According to the Center for Disease Control and Prevention (CDC), babies with a birth weight of less than 5.5 pounds may be at risk of long-term health problems such as delayed motor skills, social growth, or learning disabilities. Similar complications are true for babies born at least three weeks earlier than its due date. Other issues associated with pre-term birth include respiratory problems, vision and hearing loss, or feeding and digestive problems.

The medical and dental communities concur that maintaining periodontal health is an important part of a healthy pregnancy. The clinical recommendations released by the AAP and the EFP state that non-surgical periodontal therapy is safe for pregnant women, and can result in improved periodontal health. Published concurrently in the Journal of Periodontology and Journal of Clinical Periodontology, the report provides guidelines for both dental and medical professionals to use in diagnosing and treating periodontal disease in pregnant women. In addition, the American College of Obstetricians and Gynecologists recently released a statement encouraging pregnant women to sustain their oral health and recommended regular dental cleanings during pregnancy.

"Routine brushing and flossing, and seeing a periodontist, dentist, or dental hygienist for a comprehensive periodontal evaluation during pregnancy may decrease the chance of adverse pregnancy complications," says Dr. Newhouse. "It is important for expectant mothers to monitor their periodontal health and to have a conversation with their periodontist or dentist about the most appropriate care. By maintaining your periodontal health, you are not only supporting your overall health, but also helping to ensure a safe pregnancy and a healthy baby," says Dr. Newhouse.

Poor oral health linked to cancer-causing oral HPV infection

Poor oral health, including gum disease and dental problems, was found to be associated with oral human papillomavirus (HPV) infection, which causes about 40 percent to 80 percent of oropharyngeal cancers, according to a study published in Cancer Prevention Research, a journal of the American Association for Cancer Research.

"Poor oral health is a new independent risk factor for oral HPV infection and, to our knowledge, this is the first study to examine this association," said Thanh Cong Bui, Dr.P.H., postdoctoral research fellow in the School of Public Health at the University of Texas Health Sciences Center in Houston. "The good news is, this risk factor is modifiable — by maintaining good oral hygiene and good oral health, one can prevent HPV infection and subsequent HPV-related cancers."

The researchers found that among the study participants, those who reported poor oral health had a 56 percent higher prevalence of oral HPV infection, and those who had gum disease and dental problems had a 51 percent and 28 percent higher prevalence of oral HPV infection, respectively. In addition, the researchers were able to associate oral HPV infections with number of teeth lost.

Similar to genital HPV infection, oral HPV infection can be of two kinds: infection with low-risk HPV types that do not cause cancer, but can cause a variety of benign tumors or warts in the oral cavity, and infection with high-risk HPV types that can cause oropharyngeal cancers.

Bui, Christine Markham, Ph.D., and colleagues used data from the 2009-2010 National Health and Nutrition Examination Survey (NHANES) conducted by the National Center for Health Statistics of the Centers for Disease Control and Prevention. This survey consisted of a nationally representative sample of about 5,000 people recruited each year, located in counties across the United States.

The researchers identified 3,439 participants aged 30 to 69 years from NHANES, for whom data on oral health and the presence or absence of 19 low-risk HPV types and 18 high-risk HPV types in the oral cavity were available. Oral health data included four measures of oral health: self-rating of overall oral health, presence of gum disease, use of mouthwash to treat dental problems within past seven days of the survey, and number of teeth lost. They examined data on age, gender, marital status, marijuana use, cigarette smoking, and oral sex habits, among others, which influence HPV infection.

The researchers found that being male, smoking cigarettes, using marijuana, and oral sex habits increased the likelihood of oral HPV infection. They also found that self-rated overall oral health was an independent risk factor for oral HPV infection, because this association did not change regardless of whether or not the participants smoked or had multiple oral sex partners.

Because HPV needs wounds in the mouth to enter and infect the oral cavity, poor oral health, which may include ulcers, mucosal disruption, or chronic inflammation, may create an entry portal for HPV, said Bui. There is, however, currently not enough evidence to support this, and further research is needed to understand this relationship, he said.

"Although more research is needed to confirm the causal relationship between oral health and oral HPV infection, people may want to maintain good oral health for a variety of health benefits," said Bui. "Oral hygiene is fundamental for oral health, so good oral hygiene practices should become a personal habit."

A Glass of Milk After Eating Sugary Cereals May Prevent Cavities

Washing down sugary breakfast cereal with milk after eating reduces plaque acid levels and may prevent damage to tooth enamel that leads to cavities, according to new research at the University of Illinois at Chicago College of Dentistry.

Dry ready-to-eat, sugar-added cereals combine refined sugar and starch. When those carbohydrates are consumed, bacteria in the dental plaque on tooth surfaces produce acids, says Christine Wu, professor of pediatric dentistry and director of cariology, who served as principal investigator of the study.

The research is published in the July issue of the Journal of the American Dental Association.

Reports have shown that eating carbohydrates four times daily, or in quantities greater than 60 grams per person per day, increases the risk of cavities.

The new study, performed by Wu's former graduate student Shilpa Naval, involved 20 adults eating 20 grams of dry Froot Loops cereal, then drinking different beverages -- whole milk, 100 percent apple juice, or tap water.

Plaque pH, or acidity, was measured with a touch microelectrode between the premolar teeth before eating; at two and five minutes after eating; and then two to 30 minutes after drinking a liquid.

The pH in plaque dropped rapidly after consuming cereal alone, and remained acidic at pH 5.83 at 30 minutes. A pH below 7 is acidic; a pH greater than 7 is basic. Pure water has a pH close to 7.

Participants who drank milk after eating sugary cereal showed the highest pH rise, from 5.75 to 6.48 at 30 minutes. Those who drank apple juice remained at pH 5.84 at 30 minutes, while water raised the pH to 6.02.

Fruit juices are considered healthy food choices, but the added sugar can be a risk to dental health, Wu said.

"Our study results show that only milk was able to reduce acidity of dental plaque resulting from consuming sugary Froot Loops," said Naval, who is currently a fellow at the Centers for Disease Control and Prevention in Atlanta. "We believe that milk helped mitigate the damaging effect of fermentable carbohydrate and overcome the previously lowered plaque pH."

Milk, with a pH ranging from 6.4 to 6.7, is considered to be a functional food that fights cavities because it promotes tooth remineralization and inhibits the growth of plaque, Wu said.

Wu says most consumers think that since milk is considered to be cavity-fighting, acid production by plaque bacteria can be minimized by mixing it with cereal. However, in an unpublished study in her lab, it was discovered that the combination of Froot Loops and milk became syrupy. Eating cereal combined with milk lowered plaque pH to levels similar to that obtained after rinsing with a 10 percent sugar solution.

Eating sugar-added cereal with milk, followed by drinking fruit juice is thus a highly cavity-causing combination, Wu said.

Diet plays an important role in oral health, Wu said. Studies of food intake and cavities have focused mainly on the sugar, or carbohydrate, content. Fewer studies have looked at how combinations of food, and the order in which they are eaten, may help fight cavities.

"Results from a previous study suggested that the last food item consumed exerts the greatest influence on subsequent plaque pH," she said. For example, eating cheese after a sugary meal reduces acid production, and consumers can modify their diet in such a way as to prevent the cavity-causing effects of sugary foods."

"If understood and implemented properly, food sequencing can be used as a public health educational tool to maintain and preserve good oral health," said Naval.

Bacterium that causes gum disease packs a 1-2 punch to the jaw

The newly discovered bacterium that causes gum disease delivers a one-two punch by also triggering normally protective proteins in the mouth to actually destroy more bone, a University of Michigan study found.

Scientists and oral health care providers have known for decades that bacteria are responsible for periodontitis, or gum disease. Until now, however, they hadn't identified the bacterium.

"Identifying the mechanism that is responsible for periodontitis is a major discovery," said Yizu Jiao, a postdoctoral fellow at the U-M Health System, and lead author of the study appearing in the recent issue of the journal Cell Host and Microbe.

Jiao and Noahiro Inohara, research associate professor at the U-M Health System, worked with William Giannobile, professor of dentistry, and Julie Marchesan, formerly of Giannobile's lab.

The study yielded yet another significant finding: the bacterium that causes gum disease, called NI1060, also triggers a normally protective protein in the oral cavity, called Nod1, to turn traitorous and actually trigger bone-destroying cells. Under normal circumstances, Nod1 fights harmful bacterium in the body.

"Nod1 is a part of our protective mechanisms against bacterial infection. It helps us to fight infection by recruiting neutrophils, blood cells that act as bacterial killers," Inohara said. "It also removes harmful bacteria during infection. However, in the case of periodontitis, accumulation of NI1060 stimulates Nod1 to trigger neutrophils and osteoclasts, which are cells that destroy bone in the oral cavity."

Giannobile, who also chairs the Department of Periodontics and Oral Medicine at the U-M School of Dentistry, said understanding what causes gum disease at the molecular level could help develop personalized therapy for dental patients.

"The findings from this study underscore the connection between beneficial and harmful bacteria that normally reside in the oral cavity, how a harmful bacterium causes the disease, and how an at-risk patient might respond to such bacteria," Giannobile said.

Consuming cheese may help protect teeth against cavities

Consuming dairy products is vital to maintaining good overall health, and it's especially important to bone health. But there has been little research about how dairy products affect oral health in particular. However, according to a new study published in the May/June 2013 issue of General Dentistry, the peer-reviewed clinical journal of the Academy of General Dentistry (AGD), consuming cheese may help protect teeth against cavities.

The study sampled 68 subjects ranging in age from 12 to 15, and the authors looked at the dental plaque pH in the subjects' mouths before and after they consumed cheese, milk, or sugar-free yogurt. A pH level lower than 5.5 puts a person at risk for tooth erosion, which is a process that wears away the enamel (or protective outside layer) of teeth. "The higher the pH level is above 5.5, the lower the chance of developing cavities," explains Vipul Yadav, MDS, lead author of the study.

The subjects were assigned into groups randomly. Researchers instructed the first group to eat cheddar cheese, the second group to drink milk, and the third group to eat sugar-free yogurt. Each group consumed their product for three minutes and then swished with water. Researchers measured the pH level of each subject's mouth at 10, 20, and 30 minutes after consumption.

The groups who consumed milk and sugar-free yogurt experienced no changes in the pH levels in their mouths. Subjects who ate cheese, however, showed a rapid increase in pH levels at each time interval, suggesting that cheese has anti-cavity properties.

The study indicated that the rising pH levels from eating cheese may have occurred due to increased saliva production (the mouth's natural way to maintain a baseline acidity level), which could be caused by the action of chewing. Additionally, various compounds found in cheese may adhere to tooth enamel and help further protect teeth from acid.

"It looks like dairy does the mouth good," says AGD spokesperson Seung-Hee Rhee, DDS, FAGD. "Not only are dairy products a healthy alternative to carb- or sugar-filled snacks, they also may be considered as a preventive measure against cavities."

Soda and illegal drugs cause similar damage to teeth

Addicted to soda? You may be shocked to learn that drinking large quantities of your favorite carbonated soda could be as damaging to your teeth as methamphetamine and crack cocaine use. The consumption of illegal drugs and abusive intake of soda can cause similar damage to your mouth through the process of tooth erosion, according to a case study published in the March/April 2013 issue of General Dentistry, the peer-reviewed clinical journal of the Academy of General Dentistry (AGD).

Tooth erosion occurs when acid wears away tooth enamel, which is the glossy, protective outside layer of the tooth. Without the protection of enamel, teeth are more susceptible to developing cavities, as well as becoming sensitive, cracked, and discolored.

The General Dentistry case study compared the damage in three individuals' mouths—an admitted user of methamphetamine, a previous longtime user of cocaine, and an excessive diet soda drinker. Each participant admitted to having poor oral hygiene and not visiting a dentist on a regular basis. Researchers found the same type and severity of damage from tooth erosion in each participant's mouth.

"Each person experienced severe tooth erosion caused by the high acid levels present in their 'drug' of choice—meth, crack, or soda," says Mohamed A. Bassiouny, DMD, MSc, PhD, lead author of the study.

"The citric acid present in both regular and diet soda is known to have a high potential for causing tooth erosion," says Dr. Bassiouny.

Similar to citric acid, the ingredients used in preparing methamphetamine can include extremely corrosive materials, such as battery acid, lantern fuel, and drain cleaner. Crack cocaine is highly acidic in nature, as well.

The individual who abused soda consumed 2 liters of diet soda daily for three to five years. Says Dr. Bassiouny, "The striking similarities found in this study should be a wake-up call to consumers who think that soda—even diet soda—is not harmful to their oral health."

AGD Spokesperson Eugene Antenucci, DDS, FAGD, recommends that his patients minimize their intake of soda and drink more water. Additionally, he advises them to either chew sugar-free gum or rinse the mouth with water following consumption of soda. "Both tactics increase saliva flow, which naturally helps to return the acidity levels in the mouth to normal," he says.

New evidence on how fluoride fights tooth decay

In an advance toward solving a 50-year-old mystery, scientists are reporting new evidence on how the fluoride in drinking water, toothpastes, mouth rinses and other oral-care products prevents tooth decay. Their report appears in the ACS journal Langumir.

Karin Jacobs and colleagues explain that despite a half-century of scientific research, controversy still exists over exactly how fluoride compounds reduce the risk of tooth decay. That research established long ago that fluoride helps to harden the enamel coating that protects teeth from the acid produced by decay-causing bacteria. Newer studies already found that fluoride penetrates into and hardens a much thinner layer of enamel than previously believed, lending credence to other theories about how fluoride works.

The report describes new evidence that fluoride also works by impacting the adhesion force of bacteria that stick to the teeth and produce the acid that causes cavities. The experiments — performed on artificial teeth (hydroxyapatite pellets) to enable high-precision analysis techniques — revealed that fluoride reduces the ability of decay-causing bacteria to stick, so that also on teeth, it is easier to wash away the bacteria by saliva, brushing and other activity.

Dental anesthesia may interrupt development of wisdom teeth in children

Researchers from Tufts University School of Dental Medicine have discovered a statistical association between the injection of local dental anesthesia given to children ages two to six and evidence of missing lower wisdom teeth. The results of this epidemiological study, published in the April issue of The Journal of the American Dental Association, suggest that injecting anesthesia into the gums of young children may interrupt the development of the lower wisdom tooth.

"It is intriguing to think that something as routine as local anesthesia could stop wisdom teeth from developing. This is the first study in humans showing an association between a routinely- administered, minimally-invasive clinical procedure and arrested third molar growth," said corresponding author, Anthony R. Silvestri, D.M.D., clinical professor in the department of prosthodontics and operative dentistry at Tufts University School of Dental Medicine.

Wisdom teeth are potentially vulnerable to injury because their development – unlike all other teeth – does not begin until well after birth. Between two and six years of age, wisdom tooth (third molar) buds begin to develop in the back four corners of the mouth, and typically emerge in the late teens or early adulthood. Not everyone develops wisdom teeth, but for those who do, the teeth often become impacted or problematic.

The American Association of Oral and Maxillofacial Surgeons reports that nine out of 10 people will have at least one impacted wisdom tooth, which can cause bad breath, pain, and/or infection. For this reason, many dentists recommend surgery to remove wisdom teeth to prevent disease or infection.

A developing wisdom tooth, called a bud, is vulnerable to injury for a relatively long time because it is tiny, not covered by bone, and only covered by a thin layer of soft tissue. When a tooth bud first forms, it is no bigger than the diameter of the dental needle itself. The soft tissue surrounding the budding tooth is close to where a needle penetrates when routine dental anesthesia is injected in the lower jaw, for example when treating cavities.

Using the Tufts digital dental record system, the researchers identified records of patients who had received treatment in the Tufts pediatric dental clinic between the ages of two and six and who also had a dental x-ray taken three or more years after initial treatment in the clinic. They eliminated records with confounding factors, such as delayed dental development, and analyzed a total of 439 sites where wisdom teeth could develop in the lower jaw, from 220 patient records.

Group one, the control group (376 sites), contained x-rays of patients who had not received anesthesia on the lower jaw where wisdom teeth could develop. Group two, the comparison group (63 sites), contained x-rays from patients who had received anesthesia.

In the control group, 1.9% of the sites did not have x-ray evidence of wisdom tooth buds. In contrast, 7.9% of the sites in the comparison group – those who had received anesthesia – did not have tooth buds. The comparison group was 4.35 times more likely to have missing wisdom tooth buds than the control group.

"The incidence of missing wisdom teeth was significantly higher in the group that had received dental anesthesia; statistical evidence suggests that this did not happen by chance alone. We hope our findings stimulate research using larger sample sizes and longer periods of observation to confirm our findings and help better understand how wisdom teeth can be stopped from developing," Silvestri continued. "Dentists have been giving local anesthesia to children for nearly 100 years and may have been preventing wisdom teeth from forming without even knowing it. Our findings give hope that a procedure preventing third molar growth can be developed."

Silvestri has previously published preliminary research on third molar tooth development, showing that third molars can be stopped from developing when non- or minimally-invasive techniques are applied to tooth buds.

Dental bib clips can harbor oral and skin bacteria even after disinfection

40 percent of bib clips retained aerobic bacteria; 70 percent retained anaerobic bacteria post-disinfection

Researchers at Tufts University School of Dental Medicine and the Forsyth Institute published a study today, "Comprehensive Analysis of Aerobic and Anaerobic Bacteria Found on Dental Bib Clips at Hygiene Clinic", that found that a significant proportion of dental bib clips harbored bacteria from the patient, dental clinician and the environment even after the clips had undergone standard disinfection procedures in a hygiene clinic. Although the majority of the thousands of bacteria found on the bib clips immediately after treatment were adequately eliminated through the disinfection procedure, the researchers found that 40% of the bib clips tested post-disinfection retained one or more aerobic bacteria, which can survive and grow in oxygenated environments. They found that 70% of bib clips tested post-disinfection retained one or more anaerobic bacteria, which do not live or grow in the presence of oxygen.

"The study of bib clips from the hygiene clinic demonstrates that with the current disinfection protocol, specific aerobic and anaerobic bacteria can remain viable on the surfaces of bib clips immediately after disinfection," said Addy Alt-Holland, M.Sc., Ph.D., Assistant Professor at the Department of Endodontics at Tufts University School of Dental Medicine and the lead researcher on the study. "Although actual transmission to patients was not demonstrated, some of the ubiquitous bacteria found may potentially become opportunistic pathogens in appropriate physical conditions, such as in susceptible patients or clinicians."

The study analyzed the clips on 20 dental bib holders after they had been used on patients treated in a dental hygiene clinic. The bib clips were sampled for aerobic and anaerobic bacterial contaminants immediately after treatment (post-treatment clips) and again after the clips were cleaned using disinfecting, alcohol-containing wipes (post-disinfection clips) according to the manufacturer instructions and the clinic's disinfection protocol.

Led by Dr. Bruce Paster, Chair of the Department of Microbiology at the Forsyth Institute, microbiologists at the Forsyth Institute used standard molecular identification techniques and a proprietary, one-of-a-kind technology that can detect 300 of the most prevalent oral bacteria, to analyze the sampled bacteria from the bib clips. The analyses found:

Immediately after treatment and before the clips had been disinfected, oral bacteria often associated with chronic and refractory periodontitis were found on 65% of the clips.
After disinfection, three of the bib clips (15%) still had anaerobic Streptococcus bacteria from the oral cavity and upper respiratory tract. Five percent (5%) of the clips still harbored at least one bacteria from the Staphylococcus, Prevotella and Neisseria species.
Additionally, after disinfection, nine clips (45%) retained at least one anaerobic bacterial isolate from skin.
"The results of our analysis show that there is indeed a risk of cross-contamination from dental bib clips. The previous patient's oral bacteria could potentially still be on the clip and the new patient has a chance of being exposed to infection by using that same bib clip," said Dr. Paster. "It is important to the clinician and the patient that the dental environment be as sterile as possible; thus it's concerning that we found bacteria on the clips after disinfection. This situation can be avoided by thoroughly sterilizing the clips between each patient or by using disposable bib holders."

Researchers involved in the study hypothesized that bacteria found on bib clips after patient care could have been transferred from patients and clinicians to the clips in different ways:

Oral bacteria present in the patient's saliva and the spray or spatter produced during dental treatments may contribute to the presence of bacteria on the disinfected bib clips.
Bacteria can also be transferred from the gloved hands of dental practitioners to the clips prior to- or during the patient's treatment.
Bacteria can be transferred from the patient's hands to the clips if the patient touches the clip.
In a previous study published in August 2012 by researchers at Tufts University School of Dental Medicine and the Forsyth Institute it was found that 20% to 30% of dental bib clips still harbor aerobic bacterial contaminants even after proper disinfection procedures. Rubber-faced metal bib clips were found to retain more bacteria than bib clips made only of metal immediately after treatment and before disinfection. Four other research reports have found bacterial contamination on dental bib holders, including research conducted by U.S. infection control specialist Dr. John Molinari, the University of North Carolina at Chapel Hill's School of Dentistry Oral Microbiology lab and the University of Witten/Herdecke in Germany.

Mercury test may overestimate exposure from dental amalgam fillings

A common test used to determine mercury exposure from dental amalgam fillings may significantly overestimate the amount of the toxic metal released from fillings, according to University of Michigan researchers.

Scientists agree that dental amalgam fillings slowly release mercury vapor into the mouth. But both the amount of mercury released and the question of whether this exposure presents a significant health risk remain controversial.

Public health studies often make the assumption that mercury in urine (which is composed mostly of inorganic mercury) can be used to estimate exposure to mercury vapor from amalgam fillings. These same studies often use mercury in hair (which is composed mostly of organic mercury) to estimate exposure to organic mercury from a person's diet.

But a U-M study that measured mercury isotopes in the hair and urine from 12 Michigan dentists found that their urine contained a mix of mercury from two sources: the consumption of fish containing organic mercury and inorganic mercury vapor from the dentists' own amalgam fillings.

"These results challenge the common assumption that mercury in urine is entirely derived from inhaled mercury vapor," said Laura Sherman, a postdoctoral research fellow in the Department of Earth and Environmental Sciences and lead author of a paper in the journal Environmental Science & Technology. A final version of the paper was published online March 20.

"These data suggest that in populations that eat fish but lack occupational exposure to mercury vapor, mercury concentrations in urine may overestimate exposure to mercury vapor from dental amalgams. This is an important consideration for studies seekingMeasuring mercury: Common test may overestimate exposure from dental amalgam fillings

ANN ARBOR—A common test used to determine mercury exposure from dental amalgam fillings may significantly overestimate the amount of the toxic metal released from fillings, according to University of Michigan researchers.

Scientists agree that dental amalgam fillings slowly release mercury vapor into the mouth. But both the amount of mercury released and the question of whether this exposure presents a significant health risk remain controversial.

Public health studies often make the assumption that mercury in urine (which is composed mostly of inorganic mercury) can be used to estimate exposure to mercury vapor from amalgam fillings. These same studies often use mercury in hair (which is composed mostly of organic mercury) to estimate exposure to organic mercury from a person's diet.

But a U-M study that measured mercury isotopes in the hair and urine from 12 Michigan dentists found that their urine contained a mix of mercury from two sources: the consumption of fish containing organic mercury and inorganic mercury vapor from the dentists' own amalgam fillings.

"These results challenge the common assumption that mercury in urine is entirely derived from inhaled mercury vapor," said Laura Sherman, a postdoctoral research fellow in the Department of Earth and Environmental Sciences and lead author of a paper in the journal Environmental Science & Technology. A final version of the paper was published online March 20.

"These data suggest that in populations that eat fish but lack occupational exposure to mercury vapor, mercury concentrations in urine may overestimate exposure to mercury vapor from dental amalgams. This is an important consideration for studies seeking to determine the health risks of mercury vapor inhalation from dental amalgams," said U-M biogeochemist Joel D. Blum, a co-author of the paper and a professor in the Department of Earth and Environmental Sciences.

The study by Sherman, Blum and their colleagues demonstrates that mercury isotopes can be used to more accurately assess human exposure to the metal—and the related health risks—than traditional measurements of mercury concentrations in hair and urine samples. Specifically, isotopes provide a novel chemical tracer that can be used to "fingerprint" both organic mercury from fish and inorganic mercury vapor from dental amalgams.

Mercury is a naturally occurring element, but more than 2,000 tons are emitted into the atmosphere each year from human-generated sources such as coal-fired power plants, small-scale gold-mining operations, metals and cement production, incineration and caustic soda production.

This mercury is deposited onto land and into water, where micro-organisms convert some of it to methylmercury, a highly toxic organic form that builds up in fish and the animals that eat them, including humans. Effects on humans include damage to the central nervous system, heart and immune system. The developing brains of fetuses and young children are especially vulnerable.

Inorganic mercury can also cause central nervous system and kidney damage. Exposure to inorganic mercury occurs primarily through the inhalation of elemental mercury vapor. Industrial workers and gold miners can be at risk, as well as dentists who install mercury amalgam fillings—though dentists have increasingly switched to resin-based composite fillings and restorations in recent years.

About 80 percent of inhaled mercury vapor is absorbed into the bloodstream in the lungs and transported to the kidneys, where it is excreted in urine. Because the mercury found in urine is almost entirely inorganic, total mercury concentrations in urine are commonly used as an indicator, or biomarker, for exposure to inorganic mercury from dental amalgams.

But the study by Sherman, Blum and their colleagues suggests that urine contains a mix of inorganic mercury from dental amalgams and methylmercury from fish that undergoes a type of chemical breakdown in the body called demethylation. The demethylated mercury from fish contributes significantly to the amount of inorganic mercury in the urine.

The U-M scientists relied on a natural phenomenon called isotopic fractionation to distinguish between the two types of mercury. All atoms of a particular element contain the same number of protons in their nuclei. However, a given element can have various forms, known as isotopes, each with a different number of neutrons in it nucleus.

Mercury has seven stable (nonradioactive) isotopes. During isotopic fractionation, different mercury isotopes react to form new compounds at slightly different rates. The U-M researchers relied on a type of isotopic fractionation called mass-independent fractionation to obtain the chemical fingerprints that enabled them to distinguish between exposure to methylmercury from fish and mercury vapor from dental amalgam fillings. to determine the health risks of mercury vapor inhalation from dental amalgams," said U-M biogeochemist Joel D. Blum, a co-author of the paper and a professor in the Department of Earth and Environmental Sciences.

The study by Sherman, Blum and their colleagues demonstrates that mercury isotopes can be used to more accurately assess human exposure to the metal—and the related health risks—than traditional measurements of mercury concentrations in hair and urine samples. Specifically, isotopes provide a novel chemical tracer that can be used to "fingerprint" both organic mercury from fish and inorganic mercury vapor from dental amalgams.

Mercury is a naturally occurring element, but more than 2,000 tons are emitted into the atmosphere each year from human-generated sources such as coal-fired power plants, small-scale gold-mining operations, metals and cement production, incineration and caustic soda production.

This mercury is deposited onto land and into water, where micro-organisms convert some of it to methylmercury, a highly toxic organic form that builds up in fish and the animals that eat them, including humans. Effects on humans include damage to the central nervous system, heart and immune system. The developing brains of fetuses and young children are especially vulnerable.

Inorganic mercury can also cause central nervous system and kidney damage. Exposure to inorganic mercury occurs primarily through the inhalation of elemental mercury vapor. Industrial workers and gold miners can be at risk, as well as dentists who install mercury amalgam fillings—though dentists have increasingly switched to resin-based composite fillings and restorations in recent years.

About 80 percent of inhaled mercury vapor is absorbed into the bloodstream in the lungs and transported to the kidneys, where it is excreted in urine. Because the mercury found in urine is almost entirely inorganic, total mercury concentrations in urine are commonly used as an indicator, or biomarker, for exposure to inorganic mercury from dental amalgams.

But the study by Sherman, Blum and their colleagues suggests that urine contains a mix of inorganic mercury from dental amalgams and methylmercury from fish that undergoes a type of chemical breakdown in the body called demethylation. The demethylated mercury from fish contributes significantly to the amount of inorganic mercury in the urine.

The U-M scientists relied on a natural phenomenon called isotopic fractionation to distinguish between the two types of mercury. All atoms of a particular element contain the same number of protons in their nuclei. However, a given element can have various forms, known as isotopes, each with a different number of neutrons in it nucleus.

Mercury has seven stable (nonradioactive) isotopes. During isotopic fractionation, different mercury isotopes react to form new compounds at slightly different rates. The U-M researchers relied on a type of isotopic fractionation called mass-independent fractionation to obtain the chemical fingerprints that enabled them to distinguish between exposure to methylmercury from fish and mercury vapor from dental amalgam fillings.

Fluoride in Drinking Water Cuts Tooth Decay in Adults

A new study conducted by researchers at the University of North Carolina at Chapel Hill and the University of Adelaide, Australia, has produced the strongest evidence yet that fluoride in drinking water provides dental health benefits to adults, even those who had not received fluoridated drinking water as children.

In the first population-level study of its kind, the study shows that fluoridated drinking water prevents tooth decay for all adults regardless of age, and whether or not they consumed fluoridated water during childhood.

Led by UNC School of Dentistry faculty member Gary Slade, the study adds a new dimension to evidence regarding dental health benefits of fluoridation.

"It was once thought that fluoridated drinking water only benefited children who consumed it from birth," explained Slade, who is John W. Stamm Distinguished Professor and director of the oral epidemiology Ph.D. program at UNC. "Now we show that fluoridated water reduces tooth decay in adults, even if they start drinking it after childhood. In public health terms, it means that more people benefit from water fluoridation than previously thought."

The researchers analyzed national survey data from 3,779 adults aged 15 and older selected at random from the Australian population between 2004 and 2006. Survey examiners measured levels of decay and study participants reported where they lived since 1964. The residential histories of study participants were matched to information about fluoride levels in community water supplies. The researchers then determined the percentage of each participant's lifetime in which the public water supply was fluoridated.

The results, published online in the Journal of Dental Research, show that adults who spent more than 75 percent of their lifetime living in fluoridated communities had significantly less tooth decay (up to 30 percent less) when compared to adults who had lived less that 25 percent of their lifetime in such communities.

"At this time, when several Australian cities are considering fluoridation, we should point out that the evidence is stacked in favor of long-term exposure to fluoride in drinking water," said Kaye Roberts-Thomson, a co-author of the study. "It really does have a significant dental health benefit."

Postmenopausal women who have smoked are at much higher risk of losing their teeth

Postmenopausal women who have smoked are at much higher risk of losing their teeth than women who never smoked, according to a new study published and featured on the cover of the Journal of the American Dental Association by researchers at the University at Buffalo.

The study involved 1,106 women who participated in the Buffalo OsteoPerio Study, an offshoot of the Women’s Health Initiative, (WHI), the largest clinical trial and observational study ever undertaken in the U.S., involving more than 162,000 women across the nation, including nearly 4,000 in Buffalo.

The UB study is the first to examine comprehensive smoking histories for participants that allowed the researchers to unravel some of the causes behind tooth loss in postmenopausal women who smoked.

The study, which appears in the journal’s current issue is available at http://jada.ada.org/content/144/3/252.full.

Smoking has long been associated with tooth loss, but postmenopausal women, in particular, experience more tooth loss than their male counterparts.

“Regardless of having better oral health practices, such as brushing and flossing, and visiting the dentist more frequently, postmenopausal women in general tend to experience more tooth loss than men of the same age,” says Xiaodan (pronounced Shee-ao-dan) Mai, a doctoral student in epidemiology in the UB Department of Social and Preventive Medicine in the School of Public Health and Health Professions. “We were interested in smoking as a variable that might be important.”

While fewer adults lose their teeth now than in past decades, tooth loss is associated with poor health outcomes, including stroke, cancer, rheumatoid arthritis and diabetes.

In the UB study, heavy smokers -- defined as those who had at least 26 pack-years of smoking, or the equivalent of having smoked a pack a day for 26 years -- were nearly twice as likely to report having experienced tooth loss overall and more than six times as likely to have experienced tooth loss due to periodontal disease, compared to those who never smoked.

Participants provided information to researchers using a detailed questionnaire covering smoking history. Each participant also underwent a comprehensive oral examination and reported to the dental examiners reasons for each tooth lost. In some cases, the patient’s dental records also were reviewed.

“We found that heavy smokers had significantly higher odds of experiencing tooth loss due to periodontal disease than those who never smoked,” explains Mai. “We also found that the more women smoked, the more likely they experienced tooth loss as a result of periodontal disease.”

On the other hand, they found that smoking was a less important factor in tooth loss due to caries. That’s an important distinction, says Mai.

“Periodontal disease is a chronic, inflammatory condition that may be related to the development of cancer,” she explains.

The paper notes that cigarette smoke may accelerate periodontal disease and that other studies suggest that chemicals found in smoke may favor plaque-forming bacteria that could reduce the ability of saliva to be antioxidative. Nicotine also has been shown to reduce bone density and bone mineral factors while estrogen hormones have been found to be lower among women who smoke.

Mai is now interested in pursuing research that could determine whether smokers with periodontal disease are at even greater risk for certain cancers than smokers without periodontal disease.

“Tooth loss due to periodontal disease is a prevalent condition among postmenopausal women that severely impacts their dietary intake, aesthetics, and overall quality of life,” says Mai. “Women now have yet another, very tangible reason for quitting smoking.”

- See more at: http://www.buffalo.edu/news/releases/2013/03/002.html#sthash.c2iyIrI2.dpuf

Using mouthrinse reduces plaque and gingivitis more than toothbrushing alone

New research published in the January/February 2013 issue of General Dentistry, the peer-reviewed clinical journal of the Academy of General Dentistry (AGD), indicates that the use of a germ-killing mouthrinse in addition to regular toothbrushing can significantly reduce plaque and gingivitis, more so than brushing alone.

"It's simple—mouthrinses can reach nearly 100 percent of the mouth's surfaces, while brushing focuses on the teeth, which make up only 25 percent of the mouth," says Christine A. Charles, RDH, BS, lead author of the study and director of Scientific and Professional Affairs, Global Consumer Healthcare Research and Development, Johnson & Johnson Consumer and Personal Products Worldwide.

"Even with regular brushing and flossing, bacteria often are left behind." The General Dentistry study found that using a germ-killing mouthrinse twice a day, in addition to regular brushing, can significantly reduce the occurrence of plaque, as well as gingivitis—the beginning stage of gum disease. The six-month study included 139 adults with mild to moderate plaque and gingivitis who were separated into two groups. Members of the first group brushed their teeth and rinsed with a germ-killing mouthrinse twice daily; members of the second group brushed their teeth and rinsed with a placebo mouthrinse twice daily.

"Results show that the group using a germ-killing mouthrinse reduced its occurrence of plaque by up to 26.3 percent," says AGD Spokesperson Janice Pliszczak, DDS, MS, MBA, MAGD. "Furthermore, that same group showed a 20.4 percent reduction in gingivitis." Additionally, following the six-month study, nearly 100 percent of participants using the germ-killing mouthrinse showed a reduction in gingivitis, while only 30 percent of the placebo group experienced similar results. "The study demonstrates the oral health benefits of regular and consistent daily use of a germ-killing mouthrinse," says Ms. Charles.

"Most people brush their teeth for less than 1 minute, when, at the very least, they should be brushing for 2 minutes. Additionally, only 2 to 10 percent of people floss regularly and effectively," adds Dr. Pliszczak. "Adding a germ-killing mouthrinse twice a day to your daily routine is another way to attack the germs that can cause significant oral health problems." Dr. Pliszczak notes that not all mouthrinses are formulated to kill germs—some are meant for anti-cavity or whitening purposes—so be sure to read product labels.

Being overweight linked to higher risk of gum disease

Impacting approximately one-third of the U.S. population, obesity is a significant health concern for Americans. It's a risk factor for developing type 2 diabetes, heart disease, and certain forms of cancer, and now, according to an article published in the January/February 2013 issue of General Dentistry, the peer-reviewed clinical journal of the Academy of General Dentistry (AGD), it also may be a risk factor for gum disease.

"We know that being overweight can affect many aspects of a person's health," says Charlene Krejci, DDS, MSD, lead author of the article. "Now researchers suspect a link exists between obesity and gum disease. Obese individuals' bodies relentlessly produce cytokines, proteins with inflammatory properties. These cytokines may directly injure the gum tissues or reduce blood flow to the gum tissues, thus promoting the development of gum disease."

Half of the U.S. population age 30 and older is affected by gum disease—a chronic inflammatory infection that impacts the surrounding and supporting structures of the teeth. Gum disease itself produces its own set of cytokines, which further increases the level of these inflammatory proteins in the body's bloodstream, helping to set off a chain reaction of other inflammatory diseases throughout the body. Research on the relationship between obesity and gum disease is still ongoing.

"Whether one condition is a risk factor for another or whether one disease directly causes another has yet to be discovered," says AGD Spokesperson Samer G. Shamoon, DDS, MAGD. "What we do know is that it's important to visit a dentist at least twice a year so he or she can evaluate your risks for developing gum disease and offer preventive strategies."

The best way to minimize the risk of developing gum disease is to remove plaque through daily brushing, flossing, rinsing, and professional cleanings. "A dentist can design a personalized program of home oral care to meet each patient's specific needs," says Dr. Shamoon.

Nature-inspired advance for treating sensitive teeth

Taking inspiration from Mother Nature, scientists are reporting an advance toward preventing the tooth sensitivity that affects millions of people around the world. Their report on development of the substance, similar to the adhesive that mussels use to attach to rocks and other surfaces in water, appears in the journal ACS Applied Materials & Interfaces. Quan-Li Li, Chun Hung Chu and colleagues explain that about 3 out of every 4 people have teeth that are sensitive to hot, cold, sweet or sour foods and drinks. It occurs when the hard outer enamel layer on teeth and the softer underlying dentin wear away, stimulating the nerves inside. Some sugar-free gums and special toothpastes can help reduce that tooth hyper-sensitivity. However, Li and Chu cite the need for substances that rebuild both enamel and dentin at the same time. To meet that challenge, they turned to a sticky material similar to the adhesive that mussels use to adhere to surfaces. They reasoned that it could help keep minerals in contact with dentin long enough for the rebuilding process to occur. They describe laboratory tests that involved bathing human teeth with worn-away enamel and dentin in liquid containing the sticky material and minerals. Teeth bathed in the sticky material and minerals reformed dentin and enamel. However, teeth bathed just in minerals reformed only enamel. The gooey substance "may be a simple universal technique to induce enamel and dentin remineralization simultaneously," they concluded.