title: Smoking and periodontal disease.
mesh_terms: D005881:Gingiva / Q000098:blood supply / Q000187:drug effects; D006801:Humans; D009538:Nicotine / Q000494:pharmacology; D010510:Periodontal Diseases / Q000209:etiology*; D012907:Smoking / Q000009:adverse effects*
chemical_list: D009538:Nicotine