Sweden is one of the few countries that have removed the dental health recommendation to give prophylactic antibiotics to people at a higher risk of infection of the heart valves, so-called infective endocarditis. Since the recommendation was removed in 2012, there has been no increase in this disease, a registry study from Karolinska Institutet published in the journal Clinical Infectious Diseases shows.

Infective endocarditis is a rare but life-threatening disease caused by bacterial infection of the heart valves that affects some 500 people a year in Sweden. Individuals with congenital heart disease, prosthetic heart valves or previous endocarditis are at higher risk of infection.

People at a higher risk of infective endocarditis in Sweden used to receive the antibiotic amoxicillin as a prophylactic ahead of certain dental procedures, such as tooth extraction, tartar scraping and surgery. This recommendation was lifted due to a lack of evidence that the treatment was necessary and to help prevent antibiotic resistance by reducing antibiotic use. A collaborative project involving researchers from Karolinska Institutet has now studied how the decision has affected the incidence of infective endocarditis.

Niko Vähäsarja, the study’s corresponding author, said: “We can only see small, statistically non-significant variations in morbidity, nothing that indicates a rise in this infection in the risk group since 2012. Our study therefore supports the change in recommendation”.

After the change in recommendation in 2012, prescriptions of amoxicillin in dentistry declined by approximately 40%. However, the study is unable to demonstrate that this was an effect of the amended recommendation and amoxicillin has other uses in dental medicine.

From: https://www.sciencedaily.com/releases/2022/02/220217141205.htm

Nocturnal teeth grinding and clenching of the upper and lower jaw are known as sleep bruxism and can have consequences for health. In dental science, the question of whether sleep bruxism is associated with the development or progression of temporomandibular joint (TMJ) disorders is controversial. In a study conducted at the University Clinic of Dentistry of the Medical University of Vienna, it was found that certain tooth shapes and locations could lead to TMJ problems as a result of bruxism. The research findings were published in the Journal of Advanced Research.

The often immense pressure exerted on tooth surfaces and on the jaws is thought to cause various dental health problems and can also result in pain in the jaw muscles and headaches. Researchers led by Benedikt Sagl in Vienna have now investigated whether sleep bruxism can also have a negative impact on the TMJ structures. Their research was based on the theory that specific combinations of tooth shape and tooth location during grinding have an influence on the mechanical load on the temporomandibular joint and can thus be considered a risk factor for TMJ disorders.

“Our results show that both the inclination and location of the wear facets have an influence on the strength of the mechanical load on the temporomandibular joint,” explained Sagl, “However, it would appear that the decisive factor is the steepness of the grinding facet. The flatter the tooth, the higher the loading on the joint and therefore the higher the risk of a TMJ disorder”.

From: https://www.sciencedaily.com/releases/2022/03/220303112217.htm

There is no natural alternative to synthetic filling materials, but a new 3D model with human dental stem cells could change this in the future. The results of the research led by Prof. Hugo Vankelecom and Prof. Annelies Bronckaers have been published in Cellular and Molecular Life Sciences.

The team led by Prof. Vankelecom developed a 3D research model with stem cells from the dental follicle, a membranous tissue surrounding unerupted human teeth.

Prof. Vankelecom said: “By using dental stem cells, we can develop other dental cells with this model, such as ameloblasts that are responsible for enamel formation”.

Each day, our teeth are exposed to acids and sugars from food that can cause damage to our enamel. Enamel cannot regenerate, which makes an intervention by the dentist necessary.

Doctoral student Lara Hemeryck explained: “In our new model, we have managed to turn dental stem cells into ameloblasts that produce enamel components, which can eventually lead to biological enamel. That enamel could be used as a natural filling material to repair dental enamel. The advantage is that in this way, the physiology and function of the dental tissue is repaired naturally, while this is not the case for synthetic materials. Furthermore, there would be less risk of tooth necrosis, which can occur at the contact surface when using synthetic materials”.

Not only would dentists be able to help their patients with this biological filling material, the 3D cell model could have applications in other sectors as well. For example, it could help the food industry to examine the effect of particular food products on dental enamel, or toothpaste manufacturers to optimise protection and care.

From: https://www.sciencedaily.com/releases/2022/04/220421094131.htm

Researchers from the University of Louisville (UofL) School of Dentistry in the US and their colleagues have discovered details of how proteins produced by oral epithelial cells protect humans against viruses entering the body through the mouth. They also found that oral bacteria can suppress the activity of these cells, increasing vulnerability to infection.

A family of proteins known as interferon lambdas produced by epithelial cells in the mouth serve to protect humans from viral infection, but the oral bacteria Porphyromonas gingivalis reduces the production and effectiveness of those important frontline defenders.

“Our studies identified certain pathogenic bacterial species, P. gingivalis, which cause periodontal disease, can completely suppress interferon production and severely enhance susceptibility to viral infection,” said Juhi Bagaitkar, assistant professor in the UofL Department of Oral Immunology and Infectious Disease, “These resident oral plaque bacteria play a key role in regulating anti-viral responses”.

The mouth often is a gateway into the body for viruses that infect the gastrointestinal tract and lungs such as Covid-19, human immunodeficiency virus (HIV), herpes simplex, and cancer-causing viruses such as human papillomavirus (HPV).

P. gingivalis, a common oral bacterium that causes gum disease, has been linked to numerous other diseases, including Alzheimer’s disease and rheumatoid arthritis. Recent clinical studies have shown that immune suppression in patients with periodontitis can enhance susceptibility to HIV, herpes simplex and HPV.

Improved understanding of how interferons provide broad antiviral protection and activate antiviral genes to protect people from viruses, as well as how P. gingivalis compromises their protection, may lead researchers to clinical approaches to increase that protection.

From: https://www.sciencedaily.com/releases/2022/01/220105094341.htm

Previous studies have linked poor oral hygiene with hyper-inflammation and cardiovascular disease. Similarly, the severity of Covid-19 has been associated with hyper-inflammatory responses. Thus, researchers at Cairo University in Egypt have investigated whether there is a correlation between poor oral health and greater Covid-19 severity in patients with cardiovascular disease. They found that oral health status is an additional risk factor for such patients.

Using a questionnaire, the researchers evaluated oral health status, severity of Covid-19 symptoms, duration of recovery and C-reactive protein (CRP) levels in 308 Covid-19-positive patients and an additional 86 such patients with cardiovascular disease. The latter were the subject of a subgroup analysis. The impact of oral health on Covid-19 severity was assessed using an oral health score, and the effects of oral health on CRP levels and recovery time were assessed as secondary end points.

According to the researchers, the correlation between oral health and Covid-19 severity showed a significant inverse relationship, as did the correlation between oral health and recovery time and CRP levels. Poor oral health correlated with increased CRP levels and delayed recovery, especially in patients with cardiac disease.

Dr Ahmed Mustafa Basuoni, cardiology consultant at the University said: “Oral tissues could act as a reservoir for SARS-CoV-2 [Covid-19], developing a high viral load in the oral cavity. Therefore, we recommended maintenance of oral health and improving oral hygiene measures, especially during Covid-19 infection”.

Simple measures like practising proper oral hygiene, raising awareness of oral health importance, regular dental visits (especially in patients with cardiovascular disease), and using antimicrobial mouthwashes could help in preventing or decreasing the severity of Covid-19 disease.

From: https://www.dental-tribune.com/news/poor-oral-health-may-increase-risk-of-severe-covid-19-for-cardiac-patients/

Electric toothbrushes can remove up to twice as much plaque as a manual brush, so one could be seen as a good investment. The UK’s Oral Health Foundation has released its top-five design features for electric toothbrushes for children.

The most important element of a child’s toothbrush is the size of the head and the type of bristles it uses. The ideal children’s toothbrush should have a small head with soft bristles, suitable for the age of the child.

The handle of a children’s toothbrush is important because a good grip can help them clean their teeth more effectively. Some more colourful designs can also help to motivate children into brushing twice a day.

Pressure sensors let you know when you are brushing too hard. This often comes in the form of a warning light that appears on the handle when too much force is applied.

Research by the Oral Health Foundation shows that many children prefer an electric toothbrush simply because it has a popular character on it. These characters are often stickers that are applied to the toothbrush, which can be swapped whenever the child wants to.

Many children’s toothbrushes now come with two-minute timers. These are either in-built into the handle, are a clock or sand timer you can place in the bathroom, or connected by a mobile app.

There are lots of free apps for parents to download on their phones that can help make brushing fun for children. Adding this extra level of interactivity can help children with better brushing habits.

From: https://www.dentalhealth.org/news/top-five-must-have-design-features-for-electric-toothbrushes

Blocking the function of a blood-clotting protein prevented bone loss from periodontal (gum) disease in mice, according to research led by scientists at the National Institute of Dental and Craniofacial Research (NIDCR) in the USA. Drawing on animal and human data, the researchers found that build-up of the protein, called fibrin, triggers an overactive immune response that damages the gums and underlying bone. The study, which was published in Science, suggests that suppressing abnormal fibrin activity could hold promise for preventing or treating periodontal disease.

At sites of injury or inflammation, fibrin normally plays a protective role, helping to form blood clots and activating immune cells to fight infection. But too much fibrin has been linked with health problems, including a rare form of severe gum disease due to a condition called plasminogen (PLG) deficiency. In affected people, mutations in the PLG gene lead to fibrin build-up and disease at various body sites, including the mouth.

To explore the connection between abnormal fibrin buildup and severe gum disease, the scientists studied PLG deficiency in mice and analysed human genetic data.

Like humans with the condition, PLG-deficient mice developed severe gum disease, including periodontal bone loss and elevated levels of fibrin in the gums. The mice’s gums were crowded with immune cells called neutrophils, which are also found at high levels in common forms of severe gum disease.

Neutrophils typically defend the oral cavity from harmful microbes. But an excessive neutrophil response is thought to cause tissue damage. To find out if fibrin was driving this overactive response, the researchers impaired its ability to interact with (bind to) protein receptors on neutrophils. The weakened binding between fibrin and neutrophils completely prevented periodontal bone loss in PLG-deficient mice.

From: https://www.sciencedaily.com/releases/2021/12/211223143106.htm

Chronic inflammation caused by obesity may trigger the development of cells that break down bone tissue, including the bone that holds teeth in place, according to new University at Buffalo (UB) research that sought to improve understanding of the connection between obesity and gum disease.

The study, completed in an animal model and published in the Journal of Dental Research, found that excessive inflammation resulting from obesity raises the number of myeloid-derived suppressor cells (MDSCs), a group of immune cells that increase during illness to regulate immune function. MDSCs develop into a range of different cell types, including osteoclasts (a cell that breaks down bone tissue). Bone loss is a major symptom of periodontal (gum) disease and may ultimately lead to tooth loss.

Keith Kirkwood, professor of oral biology in the UB School of Dental Medicine says: “Although there is a clear relationship between the degree of obesity and periodontal disease, the mechanisms that underpin the links between these conditions were not completely understood”.

The study examined two groups of mice fed vastly different diets over the course of 16 weeks: one group with a low-fat diet that derived 10% of energy from fat; and, another group with a high-fat diet that drew 45% of energy from fat.

The investigation found that the high-fat diet group experienced obesity, more inflammation and a greater increase of MDSCs in the bone marrow and spleen compared to the low-fat diet group. The high-fat diet group also developed a significantly larger number of osteoclasts and lost more alveolar bone (the bone that holds teeth in place).

From: https://www.sciencedaily.com/releases/2021/11/211112083106.htm

A chewing gum laced with a plant-grown protein serves as a “trap” for the SARS-CoV-2 (Covid-19) virus, reducing viral load in saliva and potentially tamping down transmission, according to a new study.

The work, led by Henry Daniell at Penn’s School of Dental Medicine could lead to a low-cost tool in the arsenal against the Covid-19 pandemic. The study was published in the journal Molecular Therapy.

Daniell says: “SARS-CoV-2 replicates in the salivary glands, and we know that when someone who is infected sneezes, coughs, or speaks some of that virus can be expelled and reach others. This gum offers an opportunity to neutralise the virus in the saliva, giving us a simple way to possibly cut down on a source of disease transmission”.

Prior to the pandemic, Daniell had been studying the angiotensin-converting enzyme 2 (ACE2) protein in the context of treating hypertension. Daniell’s past work on ACE2 proved fortuitous in the context of the Covid-19 pandemic. The receptor for ACE2 on human cells also happens to bind the Covid-19 spike protein. Other research groups have shown that injections of ACE2 can reduce viral load in people with severe infections.

To test the chewing gum, the team grew ACE2 in plants, paired with another compound that enables the protein to cross mucosal barriers and facilitates binding, and incorporated the resulting plant material into cinnamon-flavoured gum tablets. Incubating samples obtained from nasopharyngeal swabs from Covid-positive patients with the gum, they showed that the ACE2 present could neutralise Covid-19 viruses.

From: https://www.sciencedaily.com/releases/2021/12/211203151425.htm

One of the main ways in which Covid-19 is communicated is through airborne respiratory droplets—droplets that can be dispersed as a result of dental procedures. In a new study, researchers from Newcastle University examined the applicability of local exhaust ventilation (LEV) systems for controlling the dispersion of these droplets and aerosols and found that they could be quite valuable for this purpose.

According to James Allison, lead author of the study and a clinical research fellow at the university’s School of Dental Sciences, LEV is often referred to as extra-oral scavenging or suction when used in dental settings. While such systems are employed in other industries to reduce exposure to airborne contaminants, their use is not currently commonplace in dentistry. To investigate the potential benefits of LEV systems in dentistry, Allison and a research group conducted experiments on dental mannequins in both an open-plan dental clinic and a single surgical room.

Ten-minute crown preparations were conducted in the open-plan clinic using an air turbine handpiece, and full-mouth ultrasonic scaling was conducted over the same duration in the surgery. In both settings, fluorescein was added as a tracer to the instruments’ irrigation reservoirs and an LEV system with HEPA filters and a flow rate of 5,000L/minute was used.

Overall, it was found that using the LEV system reduced aerosol dispersion from the air turbine handpiece by 90% within 0.5m of the procedure—a figure that increased to 99% for the ultrasonic scaler within the same proximity. For the air turbine handpiece, the detection of larger droplets within 0.5m was also reduced by 95%.

From: https://www.dental-tribune.com/news/covid-19-study-shows-benefits-of-local-exhaust-ventilation-in-dental-settings/



Color Skin