The document discusses dental stains, which can be extrinsic or intrinsic in nature. Extrinsic stains are located on the tooth surface and caused by external factors like plaque, foods/beverages, tobacco, and medications. Intrinsic stains are within the tooth structure due to conditions, materials, medications, and genetic/hereditary factors. Treatment depends on the specific cause and may include cleaning, bleaching, restorations, or consulting medical experts in case of underlying systemic issues. Maintaining good oral hygiene can help prevent extrinsic staining.

9. Red extrinsic stain at gingival margin and interproximal and incisal region-habit of chewing pan.

11. Sever tobacco stain

17. Intrinsic dental discoloration caused by trauma to the mandibular incisors that led to pulpal necrosis.

21. Tetracycline staining of mandibular teeth caused by the ingestion of tetracycline when the patient was aged 3 years.

22. Severe fluorosis of the teeth.