The negative impacts of the illicit drug trade touch every society in the world. The World Drug Report for 2005 estimates that 200 million people, or 5% of the global population age 15-64, have consumed illicit drugs at least once in the last 12 months. The UN Office on Drugs and Crime (UNODC) estimates its worldwide retail value to be $321bn. It impacts almost every level of human security from individual health, to safety and social welfare. Its consequences are especially devastating for countries with limited resources available to fight against it.
The World Drug Report 2007 places the UK in joint first place with Denmark (out of 30 European countries) for amphetamine use and in fifth place for ecstasy use. The report states that although still tiny compared to amphetamine, the amount of methamphetamine seized in Europe rose more than four-fold between 2000 and 2005.
Chemical dependency has many faces and takes many forms, including the use of depressants, stimulants, hallucinogens and alcohol. The most commonly abused stimulants are caffeine and nicotine. There are a number of Central Nervous System Stimulants (CNSSs) commonly abused by chemically dependent individuals that include over-the-counter diet pills, prescribed amphetamines, street amphetamines, methamphetamines and cocaine.
The neurochemical and clinical effects of cocaine and amphetamines are similar, although the two drugs are structurally dissimilar. The duration of the drug’s effects are also different: Cocaine has a plasma half-life of 90 minutes giving a euphoric ‘high’ of about 45 minutes. ‘Crack’ cocaine gives a high of only 15 minutes, whilst amphetamines have a plasma half-life of 6 to 12 hours, giving a ‘high’ of 3 to 6 hours.
The effects of methamphetamine on humans, however, are profound The stimulant effects from methamphetamine can last for hours, instead of minutes as with crack cocaine. Often the methamphetamine user remains awake for days. Many methamphetamine users try to alleviate the effect of the methamphetamine ‘crash’ by buffering the effects with other drugs such as cocaine or heroin. Like heroin and cocaine, methamphetamine can be snorted, smoked, or injected.
Amphetamine was first synthesized in 1887 in Germany. Nothing was done with the drug, from its discovery until the late 1920’s, when it was seriously investigated as a cure or treatment against nearly everything from depression to decongestion.
Methamphetamine, (MA) more potent and easy to make, was discovered in Japan in 1919. The crystalline powder was soluble in water, making it a perfect candidate for injection. It is still legally produced in the U.S., sold under the trade name Desoxyn. It is prescribed mainly for use in attention deficit disorder, obesity and more recently narcolepsy .
During World War II, amphetamines were widely used to keep the fighting soldiers active. During the Vietnam War, American soldiers used more amphetamines than the rest of the world did during WWII. In Japan, intravenous methamphetamine abuse reached epidemic proportions immediately after World War II, when supplies stored for military use became available to the public.
MA is used in pill or powdered form, and can be injected, snorted, smoked or taken orally. It is a bitter tasting powder that readily dissolves in beverages. Another common form of the drug is a clear, chunky crystal. This is the form known as ‘ice’ or ‘crystal meth’ and it is smoked in a manner similar to crack cocaine.
Clandestine production accounts for most of the methamphetamine trafficked and abused worldwide. The illicit manufacture of methamphetamine can be accomplished in a variety of ways, but is produced most commonly using the ephedrine / pseudoephedrine reduction method. Methamphetamine is also made from a mix of toxic substances, including over-the-counter cold medicine, fertilizer, battery acid, hydrogen peroxide, anhydrous ammonia (farm fertilizer), lithium (from batteries), paint thinner, ether, drain cleaner and lighter fluid. The oral effects of methamphetamine use, therefore, can be devastating.
Oral Effects of Methamphetamine
The toxic and caustic ingredients involved in the making of the drug have devastating effects on the oral tissues. The main effects being rampant caries, increased wear associated with bruxism, xerostomia and possibly periodontal disease .
Reports have described rampant caries that resembles early childhood caries, this being referred to as ‘meth mouth’. In 1995 Howe noted the incidence of gross caries was much higher in children receiving prescribed MA for obesity and attention deficit disorders. By 2002 Shaner was reporting a distinctive pattern of caries in MA users, involving the buccal smooth surface of the teeth and the interproximal surfaces of the anterior teeth. The teeth of MA users have also been described as ‘blackened, stained rotting, crumbling or falling apart’.
The rampant caries associated with methamphetamine use has been attributed to the acidic nature of the drug, drug induced xerostomia, its propensity to cause cravings for high calorie carbonated beverages and bruxism, and its long duration of action leading to extended periods of poor oral hygiene. The type of carious lesions seen in these individuals resembles ‘radiation decay’. It is large, dark in colour and appears at the cervical one third of the tooth at the gingival margin.
The xerostomic effects of MA have been attributed to the fact that MA as a sympathomimetic amine, acts on badrenergic receptors. The stimulation of areceptors in the vasculature of the salivary glands produces vasoconstriction and reduces salivary flow . This reduces the availability of the protective factors found in saliva. Xerostomia has also been attributed to the elevated metabolism and over activity experienced with MA use.
Other risk factors associated with MA use include increase bruxism and clenching. Methamphetamine is a neurotoxin and potent stimulant, which can also cause cerebral oedema and haemorrhage, paranoia and hallucinations. Short-term effects include insomnia, hyperactivity, decreased appetite, increased respiration and tremors, and drug induced grinding.
A distinct pattern of tooth wear has been reported in MA users. Richards et al noted that users who preferentially snorted MA had significantly higher tooth wear in the anterior maxillary teeth than patients who injected, smoked, or ingested it. It was suggested that patients who use MA have distinct patterns of wear based on route of administration, the difference being explained anatomically.
There is some debate whether these drugs directly contribute to periodontal disease, or whether patient neglect or apathy is the primary cause. The amphetamine Cocaine is known to cause small vessel vasoconstriction, which retards the healing process, which would, therefore be a factor in the progression of periodontal disease. An increased risk of xerostomia and anorexia caused by the drugs are also deemed to be predominant risk factors in the development of periodontal disease. These patients therefore have an increased need for good oral hygiene. Use of a sonic power toothbrush will be an advantage for these patients.
Use of a sonic toothbrush (Sonicare series) may also be of use as not only does the sonic frequency promote the production of saliva , providing added protection, but also very little manual pressure is required to remove plaque and effectively clean periodontal pockets . Another advantage of using Sonicare is the lack of wear to exposed dentine during brushing and a reduction in dentine hypersensitivity . This coupled with the lack of soft tissue trauma makes Sonicare particularly useful where the oral tissues are compromised.
Dental Treatment Considerations
There are a number of systemic effects resulting from MA use, which could affect the delivery of dental treatment. The use of central nervous system stimulants could induce life-threatening complications such as cardiac arrest, a hypertensive crisis or a cerebrovascular incident. With high doses there may be an increase in both systolic and diastolic blood pressure due to cardiac stimulation. In addition, methamphetamine may produce arrhythmias. Other systemic effects include: shortness of breath, hyperthermia, nausea, vomiting and diarrhoea.
Those individuals who have recently used cocaine or amphetamines may be hyperkinetic, hypertensive, or may experience tachycardia or tachypenia. The introduction of any vasoconstrictor in a local anaesthetic, for example at this time could be fatal. Drugs such as cocaine, methamphetamine and ecstasy have been shown to have dangerous interactions with common dental anaesthetics. These, in turn, could cause major hypertensive episodes or other health problems. Amphetamine addicts may also be resistant to general anaesthesia.
In addition to snorting or smoking, MA can also injected. An individual with a history of IV drug use should be evaluated for organic valvular heart disease, which places these individuals at risk for developing sub-acute bacterial endocarditis after an invasive dental procedure. IV drug users are also at greater risk of HIV and Hepatitis B infection. If the individual has also abused alcohol, this may result in the patient being immuno-compromised and at risk when using drugs such as acetaminophen and monoamine oxidase inhibitors .
Chemical abuse is a serious national problem that has the potential to affect all of our lives. As dental health professionals, we need to be aware the systemic and oral health effects of drug abuse and how to provide safe and adequate treatment. As healthcare professionals, it is essential that we become familiar with drug abuse and how it affects our patient’s health and our own lives.
For the full list of references, please contact Tom Roberts on 01923 851756 or email [email protected]