Mercury Fillings May Be Less Toxic: Caution Still Needed
A new study on the surface chemistry of silver-colored, mercury-based dental fillings suggests that the surface forms of mercury may be less toxic than that which was previously thought. Graham George and his colleagues note that mercury-based fillings (amalgams) have been used by dentists to repair teeth for over 100 years. In recent years, their use has become controversial because of concerns about exposure to potentially toxic mercury. Even so, mercury can potentially exist in several different chemical forms, each with a different toxicity. Scientists analyzed the surface of freshly prepared metal fillings and compared these with the surface of aged fillings (about 20 years old) from a dental clinic. Fresh fillings contained metallic mercury, which can be toxic. Aged fillings, on the other hand, usually contain a form of mercury, called beta-mercuric sulfide or metacinnabar. This form is unlikely … Read more
Common Bacteria Linked to MS
Research suggests that a common oral bacteria may increase autoimmune disease. Multiple sclerosis (MS) is a disease where the immune system attacks the brain and spinal cord. It currently affects nearly around 1 in 700 people in the United States. Patients with MS have a variety of neurological symptoms, including difficulty in moving, difficulty in speech, and muscle weakness. Porphyromas gingivalis, a common oral bacterium in humans, produces a unique type of lipid, phosphorylated dihydroceramides (DHCs), which enhance inflammatory responses. These lipids are also likely produced by bacteria found in other parts of the body including the gastrointestinal tract. Researchers led byFrank C. Nichols and Robert B. Clark of the University of Connecticut Health Center administered phosphorylated DHCs in a mouse model of MS to determine if these lipids cause immune-mediated damage in autoimmune disease. The severity of disease was … Read more
Obstructive Sleep Apnea and Bruxism
New research presented at CHEST 2009 found that nearly 1 in 4 patients with obstructive sleep apnea (mostly Caucasian men) suffers from nighttime teeth grinding. Eight percent of the general US population suffers from bruxism. “The relationship between obstructive sleep apnea and sleep bruxism is usually related to an arousal response. The ending of an apneic event may be accompanied by a number of mouth phenomena, such as snoring, gasps, mumbles, and teeth grinding,” said Shyam Subramanian, MD, FCCP, Baylor College of Medicine, Houston, TX. “Men typically have more severe sleep apnea, and perhaps may have more arousal responses, which may explain the higher prevalence of teeth grinding in men. Besides, men characteristically tend to report more symptoms of sleep apnea than women, such as snoring, loud grunting, and witnessed apneas.” Anxiety and caffeine use also help explain the relationship … Read more
Dental Stem Cells Generate New Bone Tissue
An interesting article presented in Genetic Engineering and Biotechnology News discusses dental stem cells and their role of creating new bone tissue in humans. This article is based off of the procedure and results in a recent paper titled “Human Mandible Bone Defect Repair by Grafting of Dental Pulp Stem/Progenitor Cells and Collagen Sponge Biocomplexes” which has been conducted by Gianpoalo Paccio and his partners in Naples, Italy. (Europen Cells and Materials Vol.18, 2009, pages 75-83). Seventeen patients had their wisdom teeth extracted and the dental pulp stem/progenitor cells known as DPCs were eventually used to fill the injury site left by the wisdom teeth that were removed. Three months later, the patients were examined by X-ray. The sites where the wisdom teeth were extracted and filled with the DPCs (along with a collagen sponge scaffold) showed complete regeneration of … Read more