Friday, June 15, 2018

Gum disease may be a key initiator of rheumatoid arthritis related autoimmunity


The results of a study presented at the Annual European Congress of Rheumatology (EULAR 2018) demonstrates increased levels of gum disease, and disease-causing bacteria, in individuals at risk of rheumatoid arthritis (RA).1
"It has been shown that RA-associated antibodies, such as anti-citrullinated protein antibodies, are present well before any evidence of joint disease. This suggests they originate from a site outside of the joints," said Dr Kulveer Mankia of Leeds Institute of Rheumatic and Muscoskeletal Medicine and the Leeds Biomedical Research Centre (study author). "Our study is the first to describe clinical periodontal disease and the relative abundance of periodontal bacteria in these at-risk individuals. Our results support the hypothesis that local inflammation at mucosal surfaces, such as the gums in this case, may provide the primary trigger for the systemic autoimmunity seen in RA."
Rheumatoid arthritis is a chronic inflammatory disease that affects a person's joints, causing pain and disability. It can also affect internal organs. Rheumatoid arthritis is more common in older people, but there is also a high prevalence in young adults, adolescents and even children, and it affects women more frequently than men.
The prevalence of gum disease is increased in patients with RA and could be a key initiator of RA-related autoimmunity. This is because autoimmunity in RA is characterised by an antibody response to citrullinated proteins and the oral bacterium Porphyromonas gingivalis (Pg) is the only human pathogen known to express an enzyme that can generate citrullinated proteins.2
"We welcome these data in presenting concepts that may enhance clinical understanding of the key initiators of rheumatoid arthritis," said Professor Robert Landewé, Chairperson of the Scientific Programme Committee, EULAR. "This is an essential step towards the ultimate goal of disease prevention."
In results from the study, dentists diagnosed clinical gum disease in significantly more at-risk individuals than in healthy controls (73% vs. 38%, p=0.02). In addition, the percentage of sites with clinical attachment level (CAL) ?2mm, pocket depth (PD) ?4mm, bleeding on probing (BOP), periodontal disease (PDD), and active periodontal disease (PDD+BOP), were all significantly greater in the at-risk individuals compared to controls (p<0 .05="" active="" and="" at-risk="" compared="" controls.1="" in="" individuals="" more="" non-smokers="" p="" pdd="" prevalent="" to="" were="">DNA was isolated from the subgingival plaque, next to the gums, of each participant and used to measure the levels of three types of bacteria, Pg, Aggregatibacter actinomycetemcomitans (Aa) and Filifactor Alocis. Results showed that there was increased abundance of both Pg and Aa in at-risk individuals. However, in at-risk individuals, only Pg was significantly increased at healthy dental sites and was associated with the overall extent of gum disease (p<0 .001="" p="">The study included 48 at-risk individuals (positive test for anti-citrullinated protein antibodies, musculoskeletal symptoms but no clinical synovitis), 26 patients with RA and 32 healthy controls. The three groups were balanced for age, gender and smoking. At-risk individuals underwent ultrasound assessment to assess for subclinical synovitis; only two (4%) were found to have ultrasound synovitis. Dentists examined six sites per tooth in each participant and a clinical consensus was agreed in each by three dentists.1

Thursday, June 14, 2018

Water fluoridation confirmed to prevent dental decay in US children and adolescents


The fluoridation of America's drinking water was among the great public health achievements of the twentieth century but there is a scarcity of studies from the last three decades investigating the impact of water fluoridation on dental health in the U.S. population. A recent study "Water fluoridation and dental caries in U.S. children and adolescents," published in the Journal of Dental Research, evaluated associations between the availability of community water fluoridation and dental caries (decay) experience in U.S. child and adolescent populations.

In this large study, county-level estimates of the percentage of population with community water fluoridation from the Centers for Disease Control and Prevention 's Water Fluoridation Reporting System were merged with dental examination data from 10 years of National Health and Nutrition Examination Surveys (1999-2004 and 2011-2014).

The analysis showed that U.S. children and adolescents with greater access to fluoridated drinking water were less likely to experience dental caries. Counties in which over 75% of the population had access to community water fluoridation saw a 30% reduction in dental caries experience in the primary dentition, and a 12% reduction in dental caries experience in the permanent dentition, compared to counties in which less than 75% had access to community water fluoridation.

The findings are consistent with evidence from the last half-century showing that community water fluoridation continues to provide a substantial dental health benefit for U.S. children and adolescents. The current study boosts the evidence by showing that the benefit is most pronounced early in life, in the primary teeth of 2-8 year olds.

"This study confirms previously reported findings and provides additional evidence in support of water fluoridation as a core public health intervention promoting oral health," said Maria Ryan, President of the American Association for Dental Research. "AADR supports community water fluoridation as a safe and effective, evidence-based intervention for the prevention of dental caries and this report further adds to that evidence base."

Periodontal cell sheet technique promotes bone and ligament formation on dental implant


Mary Ann Liebert, Inc./Genetic Engineering News
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IMAGE: Tissue Engineering brings together scientific and medical experts in the fields of biomedical engineering, material science, molecular and cellular biology, and genetic engineering. view more 
Credit: Mary Ann Liebert, Inc., publishers
New Rochelle, NY, June 11, 2018--Researchers used periodontal ligament (PDL)-derived stem cells to create a cell sheet, attached it to a titanium implant, and transplanted it into the mandibular bone of a dog, demonstrating the formation of a periodontal-like structure containing both cementum- and PDL-like tissue. The study, which shows the feasibility of combining a regenerative cell sheet with a titanium dental implant, is published in Tissue Engineering, Part A, peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free on the Tissue Engineering website until July 11, 2018.
The article entitled "In Vivo Periodontium Formation Around Titanium Implants Using Periodontal Ligament Cell Sheet," describes the creation of a stem cell-containing cell sheet derived from a PDL. In the human mouth, the PDL helps protect against infection and the absorption of bone caused by mechanical stress. Coauthors Isao Ishikawa, DDS, PhD, Tokyo Women's Medical University (TWMU) and colleagues from TWMU and Tokyo Medical and Dental University, Japan and Chulalongkorn University, Bangkok, Thailand documented the formation of cementum, a thin bony layer that attaches the teeth to the jaw.
"This truly innovative work combines traditional dental implants with stem cell sheet technology, thus creating a particularly relevant solution to a widespread problem in dental health care," says Tissue Engineering Co-Editor-in-Chief John P. Fisher, PhD, Fischell Family Distinguished Professor & Department Chair, and Director of the NIH Center for Engineering Complex Tissues at the University of Maryland, College Park.

Friday, June 1, 2018

Scientists develop material that could regenerate dental enamel

Queen Mary University of London

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IMAGE: Close-up of the enamel-like material. view more 
Credit: Alvaro Mata
Researchers at Queen Mary University of London have developed a new way to grow mineralised materials which could regenerate hard tissues such as dental enamel and bone.
Enamel, located on the outer part of our teeth, is the hardest tissue in the body and enables our teeth to function for a large part of our lifetime despite biting forces, exposure to acidic foods and drinks and extreme temperatures. This remarkable performance results from its highly organised structure.
However, unlike other tissues of the body, enamel cannot regenerate once it is lost, which can lead to pain and tooth loss. These problems affect more than 50 per cent of the world's population and so finding ways to recreate enamel has long been a major need in dentistry.
The study, published in Nature Communications, shows that this new approach can create materials with remarkable precision and order that look and behave like dental enamel.
The materials could be used for a wide variety of dental complications such as the prevention and treatment of tooth decay or tooth sensitivity - also known as dentin hypersensitivity.
Dr Sherif Elsharkawy, a dentist and first author of the study from Queen Mary's School of Engineering and Materials Science, said: "This is exciting because the simplicity and versatility of the mineralisation platform opens up opportunities to treat and regenerate dental tissues. For example, we could develop acid resistant bandages that can infiltrate, mineralise, and shield exposed dentinal tubules of human teeth for the treatment of dentin hypersensitivity."
The mechanism that has been developed is based on a specific protein material that is able to trigger and guide the growth of apatite nanocrystals at multiple scales - similarly to how these crystals grow when dental enamel develops in our body. This structural organisation is critical for the outstanding physical properties exhibited by natural dental enamel.
Lead author Professor Alvaro Mata, from Queen Mary's School of Engineering and Materials Science, said: "A major goal in materials science is to learn from nature to develop useful materials based on the precise control of molecular building-blocks. The key discovery has been the possibility to exploit disordered proteins to control and guide the process of mineralisation at multiple scales. Through this, we have developed a technique to easily grow synthetic materials that emulate such hierarchically organised architecture over large areas and with the capacity to tune their properties."
Enabling control of the mineralisation process opens the possibility to create materials with properties that mimic different hard tissues beyond enamel such as bone and dentin. As such, the work has the potential to be used in a variety of applications in regenerative medicine. In addition, the study also provides insights into the role of protein disorder in human physiology and pathology.

Thursday, May 24, 2018

Helping dental retainers and aligners fight off bacteria



Clear, plastic aligners have been growing in popularity as alternatives to bulky, metal braces. And once the teeth are straightened, patients graduate to plastic retainers to maintain the perfect smile. But these appliances can become contaminated, so one group is now reporting in ACS Applied Materials & Interfaces that they have developed a film to prevent bacteria from growing on them.

According to the American Association of Orthodontists, more than 5 million people seek orthodontic treatments each year. These procedures include braces and aligners, a set of plastic pieces that shift the teeth slightly over time, in an attempt to fix crowded jaws, over- and under-bites and improperly aligned teeth. Clear aligners or retainers, known collectively as clear overlay appliances (COAs) are made by taking a dental cast and using pressure or heat on a plastic sheet. But bacteria frequently build up on COAs as difficult-to-treat biofilms, and the plastics easily wear down.

Scientists have turned to developing simple and affordable coatings to combat this. Drawing inspiration from super-hydrophilic antibacterial coatings on other medical devices, Hyo-Won Ahn, Jinkee Hong and colleagues wanted to see if they could make something similar for COAs in the unique oral environment.

The researchers took a polymer sheet made of polyethylene terephthalate that was modified with glycol (PETG) and layered films of carboxymethylcellulose and chitosan on it. This layered film created a super-hydrophilic surface, or a surface that loves water, that prevented bacteria from adhering. When PETG with the film was compared to the bare material, bacterial growth was reduced by 75 percent. The coated plastic also was stronger and more durable, even when tested with artificial saliva and various acidic solutions.

Tuesday, May 1, 2018

Acupuncture possible treatment for dental anxiety



Researchers have found evidence that acupuncture could help people who experience dental anxiety.
Dental anxiety affects up to an estimated 30% of the adult population in countries world-wide. Patients can experience nausea, difficulty breathing and dizziness at the thought of going to the dentist, during an examination, and following treatment.
Reasons behind dental anxiety can be various, such as fear of pain, needles or anaesthetic side effects, as well as embarrassment or feeling a loss of control.
In a review of six trials with 800 patients, researchers used a points scale to measure anxiety and studies show that anxiety reduced by eight points when dental patients were given acupuncture as a treatment. This level of reduction is considered to be clinically relevant, which means that acupuncture could be a possibility for tackling dental anxiety.
Previous clinical trials have involved acupuncture for treatment on a range of conditions, including lower back pain, depression, and irritable bowel syndrome. There is, however, limited research detailing its impact on specific cases of anxiety.
More than 120 trials across England, China, Spain, Portugal and Germany were identified as having investigated the effects of acupuncture on patients with dental anxiety, and six trials were eligible for review, with two demonstrating high quality methods.
Professor of Acupuncture, Hugh MacPherson, at the University of York's Department of Health Sciences, said: "There is increasing scientific interest in the effectiveness of acupuncture either as a standalone treatment or as an accompanying treatment to more traditional medications.
"We have recently shown, for example, that acupuncture treatment can boost the effectiveness of standard medical care in chronic pain and depression.
"Chronic pain is often a symptom of a long-term condition, so to further our understanding of the various uses of acupuncture we wanted to see what it could achieve for conditions that occur suddenly, rapidly and as a reaction to particular experiences."
Studies that compared anxiety levels between patients that received acupuncture and those that did not, showed a significant difference in anxiety scores during dental treatment. A clinically relevant reduction in anxiety was found when acupuncture was compared with not receiving acupuncture.
No conclusions could be drawn, however, between patients that received acupuncture as an intervention and those that received placebo treatment, suggesting that larger scale controlled trials are needed to increase the robustness of the findings.
Professor MacPherson said: "These are interesting findings, but we need more trials that measure the impact of acupuncture on anxiety before going to the dentist, during treatment and after treatment.
"If acupuncture is to be integrated into dental practices, or for use in other cases of extreme anxiety, then there needs to be more high quality research that demonstrates that it can have a lasting impact on the patient. Early indications look positive, but there is still more work to be done."
The research is published in the European Journal of Integrative Medicine.

Monday, April 30, 2018

Systematic treatment of periodontal disease: Advantage of further therapeutic approaches

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