Toothache or a Toxic Filling?

Most of us probably had experienced a toothache at some point in our life. If left untreated this pain could become excruciating, eventually causing swelling of the tissue due to infection leading to further complications. In such a situation, one thing that we really want to do is to get the pain taken care of by getting a filling, if that may even be an option. Unfortunately, we may not necessarily be better off by simply getting a filling. According to Naiman (2011) mercury and composite dental fillings contain dangerous toxins and after being placed into our mouth, continually release poison into our body. Approximately 50% of a dental amalgam filling is composed of liquid mercury and the other 50% is a powdered alloy containing silver, tin and copper (About Dental). This liquid form of mercury, which releases mercury vapor may be absorbed in our lungs. Certain organizations claim that the toxicity from mercury dental fillings causes multitude of issues associated with neurological and gastrointestinal problems (Amalgam/Mercury).

Latest “safer” alternative to an amalgam has been a composite dental filling. This type of filling, which is made of fillers and inorganic materials, contains bisphenol-A (BPA) in the base material that can act as a xenoestrogen. Xenoestrogens could act falsely as estrogens in disruption of the reproductive process.

Mechanically, amalgam fillings may induce fracture stresses, resulting in breaking of a tooth. Composite dental fillings may also induce stresses on a tooth due to shrink factor, or compromise the bonding margin leading to a premature failure.
Now, should we be totally concerned about dental fillings and struggle with a toothache to the point of a mandatory extraction? Fortunately for us, the situation isn’t so drastic. Amalgam fillings have been used for the past 150 years in hundreds of millions of patients (About Dental). FDA considers dental amalgam fillings safe for adults and children over the age of 6. Vapors from amalgam, which are produced during the removal or placement of a filling, are adequately controlled in the dental office by a strong vacuum suctioning. As far as dental composites, it has been shown that human exposure to BPA is minimal and poses no known health risks.

So, go ahead and take care of that broken tooth and remember that when in doubt, consult with your dentist.

References:

Naiman I. Dental Issues. Retrieved December 2, 2011, from http://www.ingridnaiman.com/

About Dental Amalgam Fillings. FDA U.S. Food and Drug Administration. Retrieved from: http://www.fda.gov/medicaldevices/productsandmedicalprocedures/dentalproducts/dentalamalgam/ucm171094.htm

Amalgam / Mercury Dental Filling Toxicity. Retrieved from: http://www.holisticmed.com/dental/amalgam/

Photo retrieved from: http://www.london-emergencydentist.co.uk/toothache.html

http://www.iaomt.org/articles/files/files276/BPA%20review.pdf

Are you taking your Meds?

How many of us can attest to incompliance with a physician’s instructions regarding treatments of infections or prevention of disease?  I am sure many of you are just as guilty as I am.  I found an interesting article that relates to hypertension, and medication nonadherence.  Medication nonadherence “is where adherence is defined as the extent to which a person’s behavior corresponds with the recommendations of their health care provider” (Pladevall & Brotons).

Most of us are knowledgeable about hypertension; however, I am going to provide some background of this disease. Approximately 50 million people in the USA  have high blood pressure.  Hypertension is a substantial problem both in terms of its prevalence and the severity of its consequences.  Variation exists between age, gender, race, and ethnicity.  Hypertension increases ones risk of developing cardiovascular disease, stroke, and renal disease.  Hypertension has become a public health concern as cardiovascular disease and stroke is the first and third leading causes of death especially in America. 

The pathological mechanism involves elevation of the blood pressure.  High pressures within the vasculature system stimulate hypertrophy of smooth muscle cells and injury to endothelium, which results in atherosclerosis.

Treatment to prevent hypertension involves lifestyle modifications such as weight reduction, alcohol limitation, aerobic exercise, limitation to sodium intake, maintenance of calcium, potassium, and magnesium intake, stress management and medications. In promote adherence to these treatments, the study focused on using techniques to ensure compliance.  The physicians allowed intervention groups to count patients pills, designated a relative for support, and handed out educational information. 

The outcome of providing intervention caused blood pressure control for up to 2.5 years, but sadly this did not improve long-term cardiovascular problems.  The study did show that multifactorial interventions are key helpers in improving adherence to antihypertensive medication, and increasing the effectiveness adherence and blood pressure management.

Reference

Pladevall, M; Brotons, C; and Rafael, G. (2010). Multicenter Cluster-Randomized Trial of a Multifactorial Intervention to Improve Antihpertensive Medication Adherence and Blood Pressure Control Among Patients at High Cardiovascula Risk (The OM99 Study). American Heart Associations. DOI: 10.1161/CIRCULAIONAHA.109.892778/DC1.

Talbert, L. R.; Dipiro T. J.; Yee, C. G. (2011). Pharmacotherapy: A Pathophysiologic Approach. New York, NY. McGraw Hill Medical.

Stress: Something to get stressed about!

As we have so diligently studied this semester, the stress response yields a number of physiological changes. Sterrenburg et al. (2004) and Horstmann & Binder (2011) studied the effects of stress. Both female and male rats were exposed to chronic variable mild stress (CVMS) for a period of two weeks in a controlled environment. In Sterrenburg's et al. study and Horstmann & Binder's review determined increased levels of corticotropin-releasing factor (CRF) in the hypothalamic paraventricular nucleus (PVN) directly after CVMS exposure.

The PVN releases corticotropin-releasing factor (CRF) which controls the hypothalamic pituitary adrenal axis (HPA). CVMS overstimulates the HPA-axis to release CRF. There are two types of glucocorticoid receptors: 1)the high affinity mineralocorticoid receptor and 2)the low affinity glucocorticoid receptor. Once the high affinity mineralocorticoid receptors are saturated, glucocorticoids begin binding to the low affinity glucocorticoid receptors. These glucocorticoid receptors trigger the negative feedback mechanism of the stress response. Horstmann & Binder note that prolonged depression is chronic stress, and so also triggers overstimulation of the HPA-axis. They also note that antidepressants actually suppress the overstimulation of the HPA-axis so that CRF release is decreased and the stress response is also decreased.

Horstmann, S & Binder, E. (2011). Glucocorticoids as predictors of treatment response in depression. Harv Rev Psychiatry. pages 125-139.

Sterrenburg, L.; Gaszner, B.; Boerrigter, J.; Santbergen, L.; Bramini, M.; Chen, A.; Peeters, B.W.M.M.; Roubos, E.; Kozicz, T. (2011). Chronic stress induces sex-specific alterations in methylation and expression of corticotropin-releasing factor gene in the rat. PLoS ONE. 6(11).

Exercise and the brain

(Picture from http://well.blogs.nytimes.com/2011/11/30/how-exercise-benefits-the-brain/?ref=health)

Many people believe that exercise increases brain function—especially memory. Several studies have focused on how exercise affects the brain. Recently, a study in Ireland tested a group of sedentary male college students (Reynolds). First the students watched a lineup of photos with faces and names of strangers and tried to recall all of the names they had just seen. Next, the groups were divided into two—one group rode a stationary bicycle at an intense pace and the other group sat quietly. Then, both groups took the memory test again. The results demonstrated that the exercised males performed significantly better on the test than they had on their first try, while the rested students did not improve their test scores (Reynolds).  

Importantly, blood samples were taken during the experiment which provided a biological explanation for the improvement in the memory test by the exercised subjects (Reynolds). Immediately after the exercise, the exercised students demonstrated higher levels of a protein known as brain-derived neurotrophic factor (BDNF). The men who remained seated throughout the experiment reported no change in the BDNF levels. BDNF is known to promote the health of nerve cells (Reynolds). Thus, the result of this study suggests that increases in BDNF provided by exercise may play a major role in improving memory and recall (Reynolds). Although, researchers have not fully understood which parts of the brain are affected.

Many other studies have used laboratory animals to tests the effects of exercise on the brain and it is well established that physical exercise can enhance hippocampal-dependent forms of learning and memory in these tested animals (Hopkins, Nitecki, & Bucci, 84). For examples, rodents have been studied demonstrating that wheel running or treadmill exercise improves spatial learning and contextual fear memory (Hopkins, Nitecki, & Bucci, 84). These effects were likely related to exercise-induced changes in hippocampal neural plasticity which includes increased neurogenesis, long-term potentiation, and enhanced expression of BDNF (Hopkins, Nitecki, & Bucci, 84).

Another comparable study was presented by Dr. Peter J. Clark on November 7, 2011, at Regis University—ShannonQ436 also blogged about his presentation. He studied mice that exercised on running wheels and demonstrated hippocampal neurogenesis in the inner layer of the dentate gyrus (Clark). His group of researchers tested these mice in cognitive tests and their results suggested that the exercise that stimulated the formation of new neurons in the hippocampus enhanced memory (Clark). 

Overall, a significant amount of research has reported that physical exercise induces specific changes in neural function and enhances learning and memory (Hopkins, Nitecki, & Bucci, 84). This is a very important area of research because the benefit of exercise on the brain is not fully understood. With the supporting studies, researchers suggest that exercise does increase memory and learning abilities. Thus, with finals quickly approaching—we should all take some study breaks and exercise!

Clark, P.J., Brzezinska, W.J., Puchalski, E.K., Krone, D.A., & Rhodes, J.S. (2009). Functional Analysis of Neurovascular Adaptations to Exercise in the Dentate Gyrus of Young Adult Mice Associated With Cognitive Gain. Hippocampus, 19(10), 937-950.

Hopkins, M.E., R. Nitecki, and D.J. Bucci. Physical exercise during adolescence versus adulthood: differential effects on object recognition memory and brain-derived neurotrophic factor levels. Neuroscience, 194: 84-94, 27 October 2011. Retrieved from http://www.sciencedirect.com.dml.regis.edu/science/article/pii/S0306452211009158.

Reynolds, Gretchen. How exercise benefits the brain. Well, November 30, 2011. Found at New York Times website. http://well.blogs.nytimes.com/2011/11/30/how-exercise-benefits-the-brain/?ref=health.