“Meth Mouth” is a term used to describe the mouth of a methamphetamine user because of the rampant tooth decay that often occurs with the use of this dangerous drug. Meth mouth is unlike any other condition that causes tooth decay. Meth addiction can cause a perfectly healthy set of teeth to turn a grayish-brown, twist and begin to fall out in a very short amount of time, sometimes in just months. While smoking, sugar, and other drugs can also cause oral damage, none can compare with the trauma inflicted by meth use.
The exact causes of meth mouth are not fully understood. Various reports have attributed the decay to the corrosive effects of the chemicals found in the drug, such as anhydrous ammonia (found in fertilizers), red phosphorus (found on matchboxes) and lithium (found in batteries), which when smoked or snorted might erode the tooth's protective enamel coating; however, contrary to popular belief, recent studies suggest that meth mouth is not a result of the toxic chemicals but more a result of meth addiction itself.
Meth mouth can occur for a number of reasons. First, meth users often become less and less concerned with their personal hygiene and sometimes stop taking care of their teeth altogether. Second, meth users crave sugary drinks, like sodas, when they're high on meth. Having a high intake of these beverages can help to cause tooth decay. The sugar combined with poor oral hygiene is a terrible combination for the mouth. Third, the use of meth slows down saliva production in the mouth - which is a natural cleanser of the oral cavity. Also, meth stimulates the grinding and clenching of teeth - this is how the teeth break apart while they are decaying.
Meth cavities usually start between two teeth, moving from cuspid to cuspid across the network of enamel. Also, the desire to grind one's molars together can easily result in multiple teeth snapping right out of the meth user's mouth. The meth mouth epidemic is widespread in prisons as well, where clean, sharp teeth are not always valued. Prisons are now obligated to devote a growing portion of their health-care budgets to emergency dental care, which costs taxpayers in every state a small fortune each year.