The tongue is examined using both direct and indirect vision. The most common place for cancer to occur on the tongue is the lateral border and the base of the tongue (very high risk area). Grasp the tip of the tongue with a gauze square and roll the tongue over on one side to observe the lateral border then repeat for the other side (Figure 48). Use the mirror to examine the posterior lateral borders if necessary (Figure 49).
Have the patient raise the tongue to the roof of the mouth to observe the ventral surface (Figure 50).
The tissues should appear pink in color with a rough surface texture on the dorsal surface and a smoother surface texture on the ventral surface. The tongue should be symmetrical in shape and in function.
Use a bidigital technique to palpate the entire tongue between the finger and thumb of one hand (Figure 51).
The tissues of the tongue should feel soft and resilient with no palpable indurations or masses. The clinician should identify the normal anatomy of the tongue including:
Atypical findings on the dorsal surface of the tongue are common. They include: fissuring (Figure 52), scalloping (Figure 53), benign migratory glossitis (Figure 54) and enlarged papillae, among others. A lingual thyroid may rarely be found on the posterior dorsal surface at the foramen cecum. Lingual varicosities are a common finding on the ventral surface of the tongue, especially in older patients. The Glands of Blandin-Nuhn (minor salivary glands found on the ventral surface of the tongue) may become enlarged prompting the need for a referral or diagnostic procedure to confirm the origin.
The tongue is the most common intraoral site for oral cancer. Therefore, any sign of pathology should be investigated thoroughly. Some of the pathological findings that are found on the tongue include:
It is also important to note if the tongue is coated with dental biofilm. The tongue is home to the highest number of bacteria found anywhere in the oral cavity. Bacteria located on the tongue have been associated with halitosis, increased pH of the saliva, and periodontal disease. Tongue cleaning and methods of cleaning the tongue should be stressed during patient education.