An Exploration of the Amalgam Use in Dental Industry - Research Paper Example

AN EXPLORATION OF THE USE OF AMALGAM IN DENTAL INDUSTRY Outline Outline 2 A- Introduction 3 B- Background 4 C- Classification of hazard 7 D- Jop descriptions 9 E- Injury and illness statistics 10 F- Toxicology 11 G- Epidemiology 11 H- Methods of protection 12 H.1- Preventive method 12 H.2- Worker protection use in the dental industry 14 I- conclusion 15 I.1- Recommendation 16 References : 29 An Exploration of the Use of Amalgam in Dental Industry A.) Introduction Providing a vital level of protection from illness, disease and injury to employees, during the course of their work, is considered one of the major goals of the International Labor Organization (ILO). The aim of ILO is to help support opportunities for men and women to obtain jobs, based on principles of equity and safety. The development of technological fields and critical competitive demands have lead to dynamic changes in current working environments, organizations, and work processes. Established occupational safety and health management systems are recognized by governments, employees and employers. Positive effects include risk reduction and increased productivity (International Labor Conference, 1998). The Health and Safety at Work Act of 1974 states that “it shall be the duty of every employer to ensure, so far as is reasonably practicable, the health, safety, and welfare at work of all his employees” (UK Parliament Statutec37, 1974). The act is designed to protect workers from unsafe conditions, whether by illness or injury, from exposure to toxins, infectious diseases, dangerous facilities, or unsafe equipment. For the dental practice, risks to dentists and assistants must be considered, in developing standards and procedures that promote health and safety, within the dental practice or dental care facility. Dental Amalgam, one of the oldest materials used in dental health care, is a combination of elemental liquid Mercury and an alloy powder, such as copper, zinc, silver, tin, palladium, or indium (Department of Health, 1998). Amalgam has been widely used for variety of medical placement circumstances or conditions and is reasonably resistant to the presence of wetness during placement (Christensen, 2005). Amalgam offer many advantages over other substances. It is inexpensive, relatively simple to manipulate or control when used in placement, hardens quickly, and lasts longer than other direct recuperative materials such as resin based compounds. This essay explores the use of amalgam in dentistry, where dental amalgam is used to repair the damaged teeth, to restore normal function. In this sense, there are many people who have damaged teeth due to infection resulting from dental caries: processes whereby the teeth undergo mineralization and demineralization is reversible because of fluoride and dental plague respectively (Health and Safety Executive, 2008). In the past several decades, dentists have used amalgam to restore damaged teeth. However, as time passed, fears that mercury might be hazardous were taken into consideration. Consequently, the use of Amalgam has gradually lessened. This paper analyzes the use of dental amalgam and explores the credibility of the fears related to health and safety, with use of dental amalgam. Moreover, the essay will include a statistical account of the prevalence of injury or illnesses associated with amalgam use in dentistry. The essay also addresses epidemiological evidence and offers recommendations that may reduce risks associated with amalgam use. B.) Background The most frequent utilized dental recuperative substance in dental fillings is dental amalgam. It was made in the early 1800s in France. Dental amalgam is made up of 43 to 54% mercury and several components of metals such as tin, silver, copper, zinc, palladium and indium (Ferracane, 2001, p.3). It has been used for many years as a recuperative material because it is cheap, strong and durable. Moreover, it is easy to apply and has bacteriostatic effects. In spite of the numerous advantages associated with amalgam in dentistry, its use has been declining. One of the contributions to this decline in the recent past is a persistent concern in aesthetic values. The colour shade of the natural tooth does not match the bright metallic colour of the amalgam. While this issue is important to many dental patients, there are additional, more serious considerations. Environmental and health concerns have also contributed to the decline in amalgam use in dentistry. Environmental concerns arise from the fact that there are emissions of mercury in the process of preparation or grounding, and emissions of amalgam waste during cremation or incineration of the deceased people. Though emissions pose a potential indirect threat to health, absorption of mercury in dental recuperative work, using amalgam, is often viewed as a more direct threat to health for dental professionals. The first or earliest occasion when amalgam was used as a dental recuperative material cannot be well traced. However, it has been recorded or reported that in the early 659 A.D, silver paste was utilized in China to repair a tooth. In 1603, Tobias Kreilius, a German dentist, explained the procedure of making a dental amalgam filling which includes the following steps: (1) mix copper sulfide with acids, (2) and then add mercury, (3) After mixing these three substances, previously mentioned, boil them, (4) at last pour the produced substance onto someone’s tooth (Greener, 1979). After many years, the combinations of different types of metals like platinum, antimony, cadmium, and bismuth came to trial for purposes of filling the destroyed teeth. In 1895, G. Black concluded the dental amalgam formula gave the best clinical suitable performance and over the next 70 years it remained unchanged. Black’s formula is comprised of liquid mercury with a powder alloy mixture of 67% silver, 27% tin, 5% copper and 1% zinc. (Anderson & McCoy, 1993, p.45). Though the composition of the various metals has changed over the years, the basic concepts of Amalgam use have remained. There are about 27,000 dentists and 55,000 dental workers employed in dental laboratories, offices, hospitals, outpatient care facilities in the United Kingdom. Aside from dentists, those working in dental practices include dental nurses, those working in dental practices include dental nurses, dental hygienists, dental technicians and dental therapists. Although dental workers are subjected to physical, biological and chemical agents, including mercury, the level of exposure is mostly within an acceptable range. However, Sullivan and Krieger (2001, p.517) posit that there are undesirable exposures and hazards like excessive quantities of mercury waste and poisonous gases that exist in the surroundings of several dental hospitals and offices. Population growth and an aging population require the need for more Dentists in the workforce. The increasing number of elderly people means that more attention is required for adult dental care like preventive, diagnostic, implants, orthodontic and operative services. In a report issued by the National Health Service (2008) “the number of dentists has increased because the number of dentists that joined the NHS in 2007/08 was 1,709, which is higher than the 1,054 dentists that left the NHS in 2006/07.” Moreover, most of people have recognized the significance of maintaining their teeth for a long period. In addition, the increase of income for many people has led to more affordable preventive dental care and this might continue and develop in future (Vancouver Public Library, 2009). As the need for dental care increases, so does the concern for increased exposure to chemical agents for both dental workers and dental patients. C.) Classification of Hazards Amalgam is a hazard in its own right. It is composed of liquid mercury, roughly 45% and a metal alloy mixture of any combination of substances, such as tin, silver, copper, zinc, palladium and indium. The amounts of alloy differ from one amalgam to another. There are low-copper and high copper alloy mixtures used in dentistry. When dental amalgam is used as a restorative material, there will be waste materials that need to be disposed and managed properly for proper health and safety of the people. The United Nations (UN) classification system of hazards is internationally recognized and utilized universally by all organizations. The UN classification system consists of nine classes of the dangerous materials. These classes are as follows: 1-Explosives hazard 2- Gases 3-Flammable and combustible liquid and gases 4- Flammable solids 5- Oxidizers and organic peroxides 6- Poisons 7- Radioactive 8- Corrosives 9- Miscellaneous Table1; The UN classification system (Global Security, 2006). The main aim of classifying hazards is to recognize the hazardous intrinsic characteristics of the materials. In addition, this classification of materials helps to realize the adverse effects related to the intrinsic characteristics of the substance. This can be done by utilization of tests and assassination of tests' outcomes against the set criteria or standards. Chemicals are hazardous when the intrinsic characteristics meet the standards. In the dentistry industry, hazards are classified as follows: 1-Physical 2-biological 3-Chemical 4-Environmental 5-Psychological Which hazard is amalgam: physical, chemical, psychological? Most of the dental health practitioners are prone risks due to occupational exposure to a wide range of hazardous chemicals and substances. Lack of adequate information related to the possible hazards in the workplace makes dentists to be more susceptible to work-related diseases and injuries than other professionals. Therefore, Amalgam may be considered a chemical and environmental hazard. Dental amalgam is a dangerous chemical substance as it is comprised of mercury, which is known to have serious health effects. The evidence will be presented under the epidemiology section. Mercury enters the body from increased grinding, temperature, electrical current, and tooth brushing. Then, it is transported through veins and arteries, nerve fibers, and the lymphatic system. Mercury vapour is absorbed directly via the lungs. The level of mercury vapour, released by dental amalgam, ranges from six to 50 micrograms per cubic meter (Gammel,1995). Additional sources of mercury contamination in the dental office come from vacuuming carpeting containing amalgam particles and open containers containing amalgam (Phinney & Halstead, 2003, p. 594). D). Job Description According to the World Health Organization (WHO), in 2007 there were an average of4 dentists to every 1000 people in 193 of WHO’s member states. This statistic is an average, as developed nations actually have far more dentists per 1000 and under-developed countries may have as few as 0.5 per 100 people. Though many are general practitioners, some may specialize in areas such as Orthodontics. In the United Kingdom, there are roughly 4.3 dentists per1000 (WHO, 2007). The General Dental Council (GDC) is the independent agency that sets standards for practice and care within the dental profession in the U.K. All dentists and workers must be registered with the GDC to work in the UK. According to the latest GDC update (2009, p.3), “the total number of registered dentists stands at 36,99 and the total number of dental care professionals stands at 55, 297.” Dentists and their assistants carry out the process of placing amalgam onto patient’s teeth, removing previous amalgam repairs and cleaning and polishing of teeth containing amalgam. Dentists and their assistants use polishers on amalgam fillings and repairs, creating a fine dust. They must often remove amalgam from the patients’ teeth, in cases where they are no longer effective or have led to tooth damage over time. According to NHS (2009) “36.0 million Courses of Treatment (CoTs) were carried out in 2007/08.” Of those courses of treatment, roughly 30% were Band 2 treatments, which include restoration or recuperative procedures. Many restorative procedures today still use dental amalgam. Mercury is the only metal in amalgam that is used in a liquid state. It vaporizes at relatively low room temperatures and allows particles to float freely. The mercury can then be absorbed through the skin or inhaled (Phinney & Halstead, 2003, p. 595). This presents a potential risk to dentists and assistants in the dental practice, who may come into contact with amalgam used for restorative procedures. Use of protective equipment and special techniques can eliminate much of the risk. However, as with any toxic substance, there are inherent risks that are present regardless of the level of precautions taken. Just as in any health care facility or chemical laboratory, there are strict precautions to be observed and regulations that should be enforced to protect the health and safety of workers. Dentists and assistants should be aware of General Dental Council regulations and proper precautions to prevent exposure to mercury and other hazards. E). Injury and illness Statistics Though dental amalgam has been used for a long time for reasons previously mentioned, its use has some consequences. According to WHO (2005), mercury, which is a component of dental amalgam, contributes to 5% of the total mercury introduced into the environment. Combined with mercury waste from clinical and laboratory devices, it totals up to 53% of mercury emissions worldwide (WHO, 2005). Medically, dental amalgam fillings subject an individual to a daily dose of mercury, though the degrees and consequences of chronic exposure remain contentious. Some studies of workers in dental practices, who come in contact with amalgam, show no effect. The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) has reviewed studies involving dental professionals and exposure to mercury. The Committee concluded that, “in healthy subjects, exposure to mercury from dental amalgam was not associated with nephrotoxicity”(COT, 1997, p.2). The Committee has found no evidence linking mercury exposure in the dentistry profession to kidney disease. The British Dental Health Foundation (2006, p.1) points to other organizations responsible for protecting workers from environmental hazards, as evidence that mercury emitted, inhaled, or ingested from amalgam is considered safe. The World Health Organization, the UK Health Department, The FDI World Dental Foundation, Swedish Medical Research Council and the U.S. Food and Drug Administration all have found the use of dental amalgam to be safe. “Most people with dental amalgam fillings show less than 5mcg(micrograms) of mercury per liter of urine. Nearly all dentists have levels below 10 mcg per liter of urine” (British Dental Health Foundation, 2006, p.3). The foundation further explains that in some workers, levels of 135 mcg have been found, and still considered safe. A study of the fertility of 418 U.S. women working as dental assistants, with exposure to dental amalgam, was conducted by Rowling et al (1994) of the National Institute of Environmental Health Sciences. Results indicate that exposure to mercury in dental practice can lead to fertility problems. “Women with high occupational exposure to mercury were less fertile than unexposed controls” (Rowling, et al, 1994). A study of 180 dentists in South Wales, conducted by Ritchie et al (2004), shows that “dentists were significantly more likely than control subjects to have suffered from disorders of the kidney.” It is evident that some researchers believe there is a link between the use of amalgam and adverse health effects for dental professionals. Other research has attempted to link mercury exposure from dental amalgam to Alzheimer’s Disease, Parkinson’s Disease and Multiple Sclerosis, though there is no conclusive Evidence to date, suggesting the use of dental amalgam causes such health problems. F.) Toxicology In the nervous system, signs and symptoms related to mercury poisoning include memory loss, sleeplessness, hand tremors, irritability, insomnia and poor physical coordination (Brunton & Duxbury, 2004). The term ‘mad hatter’s disease’ comes from a group of symptoms often displayed by hat makers, who were exposed to mercury while using it to help with matting of felt and for removal of fur from animal pelts (Anusavice, 2003). In the digestive system, mercury causes inflammation, vomiting, nausea, diarrhea and abdominal pains. Anusavice (2003) claims that less than “0.01 % of elemental mercury is absorbed in the digestive system.” So, despite the severity of symptoms, it is unlikely that mercury will be ingested and absorbed through this route. In the respiratory system, there may be respiratory failure, coughing out blood, inflamed and impaired lungs. Though such symptoms of the respiratory system are rare, it is the route of the respiratory system that appears to cause the most concern where mercury poisoning may occur. “However, it does have a high vapor pressure. Between 65% and 85% of the mercury vapor that is inhaled is retained in the body; therefore, this route is of concern in considering the contribution of mercury absorption from dental amalgam.” (Anusavice, 2003, p.404). Given this high level of mercury vapor that can be inhaled, inhalation seems the most likely route of absorption. Mercury also affects kidney by causing increase of blood and protein intake and it causes kidney failure that maybe accompanied by the increased heart rate (Ritchie & Burke, 2004). G.)Epidemiology Many people today still have amalgam fillings. There is no conclusive report that links amalgam to any health risk. According to Dr. G. Kazantzis (2002, p139), “Following exposure to mercury vapor, the earliest clinically observed adverse effects at urine mercury levels of the order of 30-100mg per gram creatinine are objectively detectable tremor, psychological disorder and impaired nerve conduction.” However, this level is much greater than the level of 135 mcg. Kazantzis also points out that allergic and immunotoxic reactions to mercury have a genetic component. This means that some Individuals may be inherently more susceptible to the effects of mercury vapors than others. Kazantzis explains that the unpredictability of genetic factors makes it difficult to set a safe level for mercury in blood or urine. Therefore, it is also difficult to set a level for which symptoms of mercury toxicity will occur. While it is evident that mercury exposure can lead to health problems, workplace exposure to mercury in dental practice may be a result of poor practices. The study discussed by Rowling et al (1994( identified some poor hygiene factors that may have influenced the level of mercury exposure and resulting decrease in fertility. Twenty three percent of respondents had contact with mercury, 49% reported not wearing gloves when preparing amalgam, 82% reported carpeting being present in patient care areas and 67% reported eating in a patient care or laboratory area, where amalgams are prepared (Rowling, et al,1994, p.30). The study also fails to make a strong case for mercury as the direct cause of decreased fertility, though it does indicate that dental assistants may be exposed to some form of toxin. In a 1998 letter sent to physicians, dentists and NHS trusts, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) advises that “where clinically reasonable, the placement or removal of amalgam fillings during pregnancy until appropriate data are available.” The COT letter further indicates that no evidence has been found to link harm to infant with use of dental amalgam in pregnant women. H). Methods of Protection H.1 Preventive method Dental amalgam waste is a source that can expose dental professionals to mercury. It can be managed through recycling. Recycling is done in order to extract mercury from amalgam waste through a process called distillation where it can be reutilized in new commodities or products to protect environmental pollution. The following steps are used in the recycling process of amalgam waste: (1) Order different sizes of amalgam capsules to reduce the quantity of amalgam waste produced, (2) Mix amalgam waste with body fluid like saliva, in such practice one should utilize PPE (personal protective clothing) like gloves, protective eyewear and masks when handling it, (3) Ask an amalgam waste specialist or recycler about any particular needs, which may be found in the various areas related to accumulating, storing, and transporting of amalgam waste, (4) Store amalgam waste in a container that is covered and labeled as ‘Amalgam for recycling’, (5) Find a recycler who has been interrogated before carrying out the process (American Dental Association, 2004). There are other practices that can be used to manage dental amalgam waste, Amalgam should not be disposed in the toilet to drain, and instead, one should utilize line cleaners in order to reduce the dissolution of dental amalgam. In addition, dental professionals should use protective clothing when handling dental amalgam. In most cases, protective coverings should be worn even without the use of amalgam, as saliva is considered a body fluid that has the potential to carry harmful pathogens. Dental amalgam waste should be stored in a lockable or covered container that should be labeled. Various types of dental amalgam can further be separated and stored in different containers, which is helpful to the recycling process in the recycling center. Bulk elemental mercury should not be used in making amalgam capsules. Furthermore, disposable amalgam capsules should not be put in garbage, infectious waste, and biohazard containers (United States Environmental Protection Agency, 2008). Some recyclers will handle extracted teeth containing dental amalgam restorations, if handled properly. Teeth containing amalgam restorations that have been extracted should be disinfected properly. In addition, chair-side traps should be utilized, to preserve and recycle dental amalgam. Chair-side traps should not be rinsed in sinks or drains. Chair-side waste and contents of recyclable chair-side waste that are disposable should be placed in a gray or silver storage container, labeled, and sealed (Carver, 2008). H.2 Worker protection for amalgam exposure used in the dental industry Dentists frequently exposed to various types pathogen found in the body fluids and patients' blood. Because of infectious microbes found in their working environment, dentists can contract infectious diseases. These diseases may include tuberculosis, hepatitis B virus and acquired immunodeficiency syndrome (AIDS), among others. For dentists to protect themselves from blood-borne pathogens, they need to use proper preventive measures like hand washing with disinfectants after handling a patient. Dental care personnel are more susceptible to acquiring hepatitis B virus than other people who work in different field. They, therefore, should receive hepatitis B vaccine (HBV). In addition, trainings are very crucial especially to the assistant workers employed by dentists in order to understand the importance of the vaccinations (Occupational Safety & Health Administration, 2008). The PPE (personal protective equipment) refers to devices or types of clothing designed to protect health care professionals from infectious diseases and harmful chemicals or compounds. Employers need to give their employees PPE when they have occupational exposure in order to eliminate or reduce the risk of contracting diseases due to contact of harmful or infectious materials. Appropriate PPE does not allow blood or any infectious material to enter into the body’s mucous membranes of the eyes, nose and mouth, or through the skin, with proper use (Occupational Safety & Health Administration, 2008). PPE used in the dentistry industry include the following equipment: gloves, masks, eye protection, face shields, aprons, gowns, and protective clothing. Gloves are known to be very helpful especially when coming into contact with the mucus membrane, skin, and body fluids such as saliva, or in a case where the dental professional may come into contact with infectious materials. The dentists use a clean, disposable pair of gloves on each patient and then disposes of them. Before handling another patient, the dentists and dental workers must wash, disinfect their hands and then put on a new pair of gloves. Utility gloves are utilized in washing the environmental surfaces and equipment. They can be recycled, if disinfected. However, they must be disposed if discoloured, cracked, punctured or showing any sign of deterioration. The use of latex gloves among workers has been boosted by the stringent requirements for occupational protection. It is true that this has contributed to increase the cases of allergic reactions owing to latex. Vinyl gloves and other protective equipment can provide a safe alternative that is just For patient and dental team's safety and health, dentists recommend for latex free surroundings or environments (Safety and Industrial Supplies, 2009). Dental practitioners should adopt the habit of wearing protective equipment like masks or face shields, to protect eyes, nasal and oral mucosa as well as the face, when droplets, splatter or spray of contagious body liquids and fluids are likely. In addition, protective clothing ought to put on anytime a dental professional comes in contact with any part of the patient s' body. The type of the protective clothing will depend on the type of work the dentist, nurse, technician or hygienist s is expected to perform (Safety and Industrial Supplies, 2009). The Control of Substances Hazardous to Health (COSHH) regulations “require employers to control substances that can harm workers’ health.” (HSE, 2009). The Health and Safety Executive suggests that all employers, including dental care facilities and surgeries, should have a plan for handling potentially toxic chemicals and should periodic COSHH assessments. Such assessments can be conducted by any worker within the dental practice, but the worker should “understand hazard and risk, know how the work can expose people to substances hazardous to health, have the ability to collect necessary information and have the knowledge, skills and experience to make the right decisions about how to control exposure.” (HSE, 2009). The HSE further encourages workers who believe they are exposed to chemicals in unsafe situations to make anonymous reports to their office. I). Conclusion As a recuperative substance, dental amalgam can be very beneficial and cost-effective. On the other hand, it has negative effects on the health of individual, animals, and environment. Possible environmental impacts associated with dental amalgam waste depend on the methods used to dispose the waste as well as the mechanisms used in treatment. A lot of concern has been raised over the last decades concerning the effects of mercury, a component of dental amalgam. Dental amalgam has been widely accepted in dental practice, due to its durability, relatively low cost, and presence of bacteriostatic agents, which help reduce the likelihood of infection. Although the medical acceptance of substitutions for dental amalgam remains, amalgam is still considered the most effective material for restorative dental care. However, environmental and related health concerns surrounding dental amalgam in the dental practice should be addressed. Any substance that contains mercury is hazardous or harmful when it is used by some persons. Hence, appropriate differentiation or separation of mercury included dental amalgam need to be addressed. In addition, amalgam is not mercury. Waste management writings, therefore, should not group amalgam as similar to mercury. Moreover, when amalgam waste is treated by using very high temperatures, one of the by-products will be mercury. It is not the existence or being of dental amalgam that lead to environmental pollution but rather it is the entire treatment process. So, this shows clearly the difference between the original sources of mercury and mercury compound as in the case of dental amalgam waste. I.1 Recommendation To avoid exposure to mercury, it is very important for both employers and employees to know all matters pertaining occupational health and safety. Suggestions of the best methods to improve occupational health should constantly be sought out, to ensure that the employees will not be harmed in any situation. Experts should also be constantly consulted when unforeseen situations arise, involving chemical exposure in the dental practice. Research involving the health effects on dental professionals exposed to mercury is currently inconclusive. Therefore, continued research on health effects of mercury exposure should be conducted within the dentistry industry, to try and determine if dental amalgam presents a more serious risk. Reference List American Dental Association, 2004. Best management practices for amalgam waste. Health and Wellness. Available at: http://www.ada.org/prof/resources/topics/topics_amalgamwaste.pdf. [Accessed 11Nov. 2009]. Anderson, M. & McCoy, B 1993. Dental amalgam: The state of the art and science. 3rdEd. Philadelphia: Saunders. Anusavice, K.,2003. Philip’s science of dental materials. 11th Ed. University of Florida, Gainesville: Elsevier Science. British Dental Health Foundation, 2009. Policy statement: Dental amalgam. 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