Dental glossary — terms beginning with L

Labial, from the Latin "labium", the lip. In dentistry it is a term of spatial orientation meaning "towards the lip".

Smile line, the line the edge of the upper lip follows when smiling.

Lesion, a disturbance or damage. Where a tooth is affected by caries, for example, the decayed area is called a carious lesion.

Laser treatment, in dentistry the laser is used above all in treating the gums. Gum disease affects many patients and leads to tooth loss more often than caries does. Conventional treatments are frequently quite arduous and painful for patients. gum caries

Local anaesthesia, elimination of pain at the site being treated; the patient remains conscious.

Gapped dentition, the term for a natural dentition in which one or more teeth are missing.