Lead toxicity can be acute or chronic in nature. Acute toxicity occurs when there is sudden exposure to higher amounts of lead. Chronic lead toxicity is long term exposure to low amounts of lead. Either the way, both the forms of toxicity mainly damage the cell membrane, and interfere with DNA transcription process.
|Figure 1 Burtons Line|
Henry Burton, a London based physician, in 1840, described, a very thin, bluish purple coloured line at the tooth and gum interface i.e., on the marginal gingival. This line is a clinical sign of chronic lead toxicity. This narrow coloured line is seen on the neck of two or more teeth of either of the jaws. Even though it is a good indicator of lead toxicity, but, not seen in every case Apart from this, gums retain their normal colour and texture. This line was later named as “Burton line” This line is seen if the blood levels of lead are more than 10 µg/dl.
This line is most commonly noticed in children especially below the age of 6 years. This may be due to ingestion of chipped off lead based painting on the walls. Otherwise also, some children have the habit of biting the lead portion of their pencils which gives them pleasure of its taste. In adults this line is due to occupational exposure.
Mechanism of Burton’s line:
Burton’s line is caused due to the interaction of the circulating lead and the sulphur ions released by oral micro flora. This causes the deposition of lead sulphide at the tooth gum interface which is referred to as burtons line.
Significance of Burton line:
If a dentist encounters any patient with Burton’s line, then that patient should be informed about the chronic lead toxicity. Later, refer the patient to the physician to seek the appropriate medical treatment.
Once the lead is removed from the body, the Burtons line will disappear after some time.