Can Dentists Tell If You Vape, Smoke, or Use Weed? Can your dentist tell if you vape? The answer is YES! Here's how we know: Dry mouth Leads to more plaque & cavities Inflamed gums Nicotine reduces How Dentists Can Tell If You Vape: Oral Health Effects Can your dentist tell if you smoke or vape? , Short answer: not really but there is a subtle tell., Nicotine is a vasoconstrictor, which means it can reduce blood flowso when your gums should be Can a Dentist Tell If You Smoke?