Illicit methamphetamine use is reported widely by news media and discussed increasingly among scholars, clinicians, and members of civic and law enforcement organizations and legislative bodies. This article examines the phenomenon of methamphetamine abuse, including its extent, its effects on both users and society, and its implications for dentistry. Meth mouth refers to a pattern of oral signs and symptoms of methamphetamine abuse, thought to include rampant caries and tooth fracture, leading to multiple tooth loss and edentulism.