Dentists can often tell if a patient smokes occasionally by examining the teeth and gums. Nicotine and tar from cigarettes can stain the teeth, cause gum disease, and lead to other oral health problems.
Smoking is a major risk factor for oral cancer, and dentists play an important role in screening for and diagnosing this disease. By identifying patients who smoke, dentists can help them to quit and reduce their risk of developing oral cancer.