lingual surface of tooth

The lingual surface of a tooth is the inner surface that faces the tongue. In the lower jaw, it is directly adjacent to the tongue, and in the upper jaw it faces the palate, where it may also be referred to as the palatal surface. It is opposite to the facial surface of the tooth.

The lingual surface is located on the tongue-facing side of every tooth in both the upper and lower dental arches. Upper teeth have this surface facing the hard palate and tongue, while lower teeth have it directly adjacent to the tongue.

The lingual surface plays a role in food processing, swallowing, and speech articulation. The tongue presses against lingual surfaces during swallowing and during production of certain speech sounds such as dental consonants. The surface contour also helps guide food during mastication.

The lingual surface may be associated with acid erosion, particularly in individuals with gastroesophageal reflux or frequent vomiting, which exposes the inner tooth surfaces to stomach acid. Calculus buildup and gum disease may also be associated with lower anterior lingual surfaces.

The lingual surface is examined using a dental mirror to deflect the tongue and provide a view of the inner tooth surfaces. Dentists assess for erosion, caries, calculus, and gingival recession along the lingual gumline during routine oral examinations.