Gum lead

It is a blue-black line with a width of about 1mm formed by the deposition of lead sulfide particles on the gingival edge of those who have been in long-term exposure to lead. It is produced by the action of hydrogen sulfide produced by the spoiled lead and the protein in the food residue between the dentition. The gingival margins of incisors, cuspids, and first molars are more common. Similar pigmentation can be seen in the mucosa of the cheeks, tongue, and other parts of the oral cavity. At present, lead lines can be seen in a large number of patients with lead poisoning by oral lead compounds or poor oral hygiene. Lead lines caused by occupational exposure are rare. Lead lines can only indicate that lead is absorbed in the body, and are not a characteristic indicator of clinical diagnosis of lead poisoning.