Normal Anatomy or Oral Pathology

Dr. Karen Burgess
Authored By:
Dr. Karen Burgess
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When you visit the dentist, part of the initial check-up is to look at the soft tissues of the mouth, as well as the teeth and bones. Looking at the tissue around the outside of the mouth is called the extra-oral exam, while the intraoral exam looks at the tissues inside the mouth. The dentist is looking for different lumps, bumps, spots, patches or anything else unusual. Most of these lumps and bumps are just variations of the normal anatomy of your mouth. However if the dentist finds anything unusual, it is important that they record it properly so that it can diagnosed. The following are terms your dentist may use to describe the appearance of features that can be observed in oral examinations.

  • A macule is a spot. Macules are well defined, flat, have a different color than the surrounding tissue and are usually less than 5 mm in diameter.
  • A patch is a larger spot. This is also a pigmented area that is generally greater than 5 mm in diameter.
  • A plaque is a slightly raised plateau-like area, and can be pigmented or not.
  • A polyp is a mass of tissue that projects outward from the surface of the mucous membranes.
  • A papule is a small slightly raised area less than 5 mm in diameter. It may be pigmented or may be the same color as the surrounding tissue.
  • A nodule is a lump larger than 5 mm. It may be visible or it may only be detectable by palpation.
  • A vesicle is a small blister less than 5 mm in diameter. It is raised, well defined and filled with clear fluid.
  • A bulla is a vesicle that is larger than 5 mm.
  • An ulcer is usually a depressed or crater-like area on the mucosa where there is a loss of the epithelium, which is the surface layer, and is often yellow white in colour.
  • An erosion is a shallow ulcer where the epithelium may only be partially destroyed. These often are red in color.
  • A petechia is a spot approximately 1 to 2 mm in diameter where blood has leaked into the surrounding tissue. These are often found in multiples, and are called petechiae.
  • An ecchymosis is a flat bruised area of haemorrhage larger than 2mm in diameter.
  • A hematoma is a localized collection of blood outside of a blood vessel that may appear raised.

Some of these shapes and appearances are a part of normal anatomy, such as polyps, nodules, macules, or papules, while others are usually due to pathology, such as ulcers, vesicles, or bullae.

After determining what type of shape it is, the dentist will accurately describe it in a way that someone else could picture the area without seeing it.

  1. The number will be recorded. For example ‚Äď is there one ulcer or three ulcers?
  2. The size will be measured accurately in 2 or 3 dimensions. For example, a white patch could measure 8 x 7 mm, while a torus is three dimensional so this one would measure 17 x 10 x 10 mm.
  3. The doctor will record the color of the area, as this may also help with the diagnosis. Vascular lesions, for example usually appear purple because there is blood in them.
  4. The location should also be documented. White areas on the floor of the mouth are more worrisome than white areas along the buccal mucosa which is the inner cheek.
  5. The surface texture may help in the diagnosis of the condition. Smooth mucosa-covered bumps often start from the underlying tissues, while papillary, or cauliflower-like lesions may be due to a virus.
  6. The consistency or feel of a mass may help determine the diagnosis.

The next step is to determine if it is normal anatomy of the mouth and throat. The following are considered to be part of the normal anatomy:

  1. The Stensen’s duct is the duct of the parotid salivary gland and the opening can be flat or polyp shaped. Milking saliva from this duct confirms that this is the Stensen’s duct.
  2. The Wharton’s duct is the duct of the submandibular gland, and the openings are on either side of the frenulum in the floor of the mouth.
  3. The sublingual glands open into the floor of the mouth in the fold of tissue called the plica sublingualis.
  4. Normal bumps on the tongue are called papillae.
    1. Filiform papillae are hair-like or thread-like projections on the front two thirds of the top of the tongue, and are usually pink or white in colour.
    2. Fungiform papillae also occur on the top of the tongue, with a higher concentration near the tip. They are mushroom shaped, and deep red in colour and contain a few taste buds.¬† Fungiform means ‚Äúshaped like fungi or mushrooms‚ÄĚ.
    3. Circumvallate or vallate papillae are 8 to 12 mushroom-shaped bumps, each surrounded with a circular trough. Circumvallate means ‚Äúaround a valley or trench‚ÄĚ. They are located in a V shape at the junction of the front two thirds of the tongue and the back third or the base of the tongue.
    4. Foliate papillae appear as 3 to 4 small folds on the side of the back of the tongue.  They are a pinkish red, soft, and contain taste buds.  They may also contain lymphoid tissue and appear yellowish beige in colour.
  5. Most people have masses of lymphoid tissue in their mouth and throat, such as the tonsils.
    1. Lingual tonsils are yellowish beige bumps on the top of the back part of the tongue, and may sometimes also be seen on the sides of the tongue. These collections of lymphoid tissue can vary in size, and may enlarge when someone has a cold. These are considered normal when they are soft, appear symmetrical, and are covered with intact mucosa. If one side is larger than the other side, or if one is firm or ulcerated, then this should be further evaluated.
    2. Pharyngeal tonsils are normal masses in the throat. These tonsils may be small or large. Normal tonsils are usually, soft, symmetrical, non-ulcerated, and asymptomatic. They may be smooth or bumpy. They often have a slightly yellow to beige appearance due to the lymphoid tissue. There may be necrotic material lodged in the tonsillar crypts which will appear as indentations in the tonsils. This material is called tonsillar concretion and is made up of dead mucosa, bacteria, and foreign material. This generally comes out on its own and does not need treatment, however, it also may smell, and cause bad breath. If this material calcifies, it is called a tonsillolith. If someone has had a tonsillectomy, you may see a scar in this area. The scar usually appears as pale lines.

There are other normal conditions that some people have and others do not. These are called ‚Äúvariations of normal‚ÄĚ. These conditions should be described, recorded, and when correctly diagnosed, do not need treatment.¬† It is common to see these conditions on oral examinations.

  1. Fordyce granules are sebaceous glands that are commonly seen on buccal mucosa or lip. They appear as groups of slightly raised, yellowish-beige papules measuring 1 to 3 mm in diameter.
  2. Fissured tongue is a common condition characterized by the presence of multiple grooves on the top or occasionally on the sides of the tongue and is reported in 2% to 5% of the population.
  3. Crenations are indentations on the sides of the tongue that are a result of the impressions from the teeth. These may be more obvious in people who press their tongue against their teeth as a habit.  
  4. Varicosities are dilated veins often seen on the underside of the tongue, particularly in older people, and may be seen in other areas such as the buccal mucosa or the lips. They are purple in colour and blanch when pressed.
  5. Plica Fimbriata are the fringe-like folds of mucosa on underside of the tongue on either side of the frenulum.
  6. Ankyloglossia, or tongue tied, is an uncommon condition where the frenulum is shorter than average. The person cannot protrude or lift his or her tongue as much as the average person.
  7. Leukoedema is a milky, white-gray translucent appearance on both sides of the buccal mucosa when the tissue is at rest. There may appear to be white streaks, due to the folding of the mucosa. This appearance disappears when the mucosa is stretched. Leukoedema is more common with people who have naturally dark skin.
  8. A palatal torus occurs in the midline of the roof of the mouth. Palatal tori do not need treatment unless they will interfere with a denture.
  9. Mandibular tori are seen on the inner surfaces of the lower jaw in the premolar region. They are rounded mucosa-covered bony swellings typically on both sides of the mouth.
  10. Exostoses are rounded protuberances or swellings of bone in other areas usually seen on the outer surfaces of the jaws.
  11. Retrocuspid papillae are firm, pink papules on the inner gums of the lower canines. They are more common in children, and may regress with age.

There are other conditions that are minor oral pathologies commonly seen on oral examination. They are classified as pathology, but are not worrisome, and do not need treatment. The appearance should be recorded and followed at regular check-ups.

  1. Linea alba or white line, appears as a white horizontal line along the buccal mucosa at the level of the occlusal plane, which is where the teeth meet. This is a common condition seen on both sides of the mouth due to frictional irritation or sucking trauma.
  2. Scars on the inner surface of the lower lip are seen frequently, and are often due to trauma as a child. There can also be scars from tonsillectomy.
  3. Mucosal tags are the oral equivalent of a skin tag. These are commonly seen on the frenulum inside the upper lip. It may be the result of healing after trauma to the frenulum. These appear as a small, soft, pink, bump.
  4. Gingival grafts appear as thicker, lighter pink mucosa often on the lower gums by the canine tooth. The person should remember having tissue taken from the hard palate for the graft.
  5. Papillitis, or transient lingual papillitis, is inflammation of one or several of the fungiform papillae on the top of the tongue. They appear slightly enlarged, and are usually white in color, but can be red or yellow. The papule or papules can be very painful. The cause is unknown and usually resolves in several days without treatment.
  6. Acute trauma from cheek biting is commonly seen along biting line of the inner cheek. If someone has bitten their cheek recently, there may be two areas of bruising corresponding to the indentation of the teeth. There may also be a ragged white area where the mucosa has been torn.
  7. Chronic cheek biting is called morsicatio buccarum. In people that habitually chew on their buccal mucosa, the area has a white, ragged slightly translucent appearance. This can also occur on the inside of the lips and the tongue.
  8. Geographic tongue appears as multiple circular or semicircular red areas on the tongue. There is usually, but not always, a slightly raised yellowish-white semicircular rim or border. The red areas may move around with time, thus its proper name is ‚Äúerythema migrans‚ÄĚ which is Latin for red areas moving. Geographic tongue is easily diagnosed if there are obvious areas with a classic appearance. It is harder to diagnose if there are only 1 or 2 small circular red areas with a faint yellow-white raised rim. Geographic tongue is seen in approximately 2% of the population, and is more common in people with fissured tongue.
  9. Hairy tongue is a benign condition of unknown cause where the filiform papillae become elongated, and hair-like. They may pick up stains from tobacco, coffee, tea or pigment-producing bacteria. Hairy tongue is more common after oral radiation treatment, and in patients that smoke. This is a very difficult condition to cure, but gently scraping or brushing the tongue may help.

An extraoral and intraoral examination may be completed as part of your dental checkup. By performing these examinations, your dentist can identify possible abnormalities or simply confirm that the different lumps, bumps, and spots are a part of your mouth’s normal anatomy. Some conditions may require further assessment and your dentist may book a follow-up appointment or refer you to a specialist to determine a diagnosis.