The question of whether or not a dentist can smoke weed is a complex one that depends on a number of factors, including the specific laws and regulations of the jurisdiction in which the dentist practices, the dentist's individual ethical beliefs, and the potential impact of marijuana use on the dentist's ability to perform their job safely and effectively.
In some jurisdictions, it is illegal for dentists to use marijuana, even for medical purposes. In other jurisdictions, dentists may be allowed to use marijuana for medical purposes, but they may still be subject to restrictions on their ability to practice while under the influence of the drug. Additionally, some dentists may choose not to use marijuana, even if it is legal in their jurisdiction, because they believe that it could impair their ability to provide safe and effective care to their patients.