13 Issue 6 | 2018 | CDA at W ork When is a dentist considered too impaired to practise? Is there an objective measure of marijuana impairment? No, not yet. Certainly, practising while impaired, from either drugs or alcohol, would be considered professional misconduct; but cannabis is new territory. Generally, it’s the provincial regulatory authorities that deal with dentists’ requirements to practise. The question is, how many hours must pass after I’ve smoked cannabis before I can treat a patient? This is an emerging discussion that is evolving quickly. For example, the Canadian Armed Forces recently announced that they were debating the specifics of cannabis impairment in light of pending legalization. Should there be a 24-hour rule that you can’t go to work or be on duty for 24 hours after having any amount of cannabis? How are impairment levels affected when both alcohol and cannabis are involved? For driving, a blood alcohol concentration of more than 0.08% is considered a criminal offence throughout Canada, and the provinces have their own rules for drivers that define the legal limits of blood alcohol levels. Where this gets difficult is when alcohol is combined with cannabis: what are the different levels of impairment for that combination? The combined effect of taking these two substances, and defining impairment in a way that considers the interaction between THC level (the active ingredient in marijuana) and blood alcohol content, is something that not many jurisdictions in the world have to deal with. On top of that, the level of impairment defined by the Criminal Code is different from the level of impairment that would constitute professional misconduct in the workplace. What should a dentist say to a patient who they suspect may have come to a dental appointment impaired? My approach is to start a conversation. Rather than relying on medical histories, I’ll start filling out the medical history together with the patient. The way in which they respond to questions gives me a good sense of where they’re at cognitively. I’ve found that if you can establish a rapport, in a very non-judgmental and open way, patients will often disclose if they are using cannabis. The next questions to consider are how much cannabis did the patient have, and can the treatment we have planned for that day be done safely on someone who is impaired? In my experience, it really can’t. Without knowing exactly how much THC was in the cannabis they smoked, it’s hard to know how they will react to treatment. Without knowing exactly how much THC was in the cannabis they smoked, it’s hard to know how a patient will react to treatment. Dr. Aaron Burry This interviewhasbeencondensedandedited. Theviewsexpressedarethoseoftheauthor anddonotnecessarilyreflecttheopinions orofficialpoliciesoftheCanadianDental Association. ManagingCannabis Impairment In The Dental Office We askedDr. Aaron Burry, CDA’s associate director of professional affairs, about how to handle cannabis impairment in the dental office.