Little is known about how different types of substances affect oral health. Our objective was to examine the respective effects of alcohol, stimulants, opioids, and marijuana on oral health in substance-dependent persons. Using self-reported data from 563 substance-dependent individuals, we found that most reported unsatisfactory oral health, with their most recent dental visit more than 1 year ago. In multivariable logistic regressions, none of the substance types were significantly associated with oral health status. However, opioid use was significantly related to a worse overall oral health rating compared to 1 year ago. These findings highlight the poor oral health of individuals with substance dependence and the need to address declining oral health among opioid users. General health and specialty addiction care providers should be aware of oral health problems among these patients. In addition, engagement into addiction and medical care may be facilitated by addressing oral health concerns.