Beneath the tongue is the area known as the floor of the mouth, where a normally thin strip of tissues called the lingual frenulum (also frenum) connects the floor of the mouth to the tongue. In some infants, the frenulum is very thick and severely limits the movement of the tongue, leading to difficulty with feeding. This disorder is called ankyloglossia. In cases where breastfeeding is inhibited, a frenectomy may be done to release the tongue. (See Chapter 11: Oral Findings).

Near the attachment of the frenulum to the floor of the mouth are the tiny openings (Wharton’s ducts) of the submandibular salivary glands. The ducts of the sublingual salivary glands are present on either side of the Wharton’s ducts. In addition, there are 2 large salivary glands, known as the Parotid glands. The Parotid glands are located along the sides of the jaw, just below and in front of the ears, between the masseter muscle and the skin. These glands empty through tiny holes called Stenson's ducts, which appear as small bumps on the inside of the cheeks near the maxillary second molars.

Failure of these glands to produce saliva leads to xerostomia, which can be caused by medical conditions (eg, Sjogren’s, sarcoidosis, lupus), medications (eg, antihistamines), or illicit drugs (eg, Crystal Meth). Examination of these glands, especially the Parotids, might lead to the discovery of parotitis (see Chapter 11: Oral Findings).