An oral torus is a lesion made of compact bone and occurs along the palate or the mandible inside the mouth. The palatal torus or "torus palatinus" occurs along the palate, close to the midline, whereas the mandibular torus or "torus mandibularis" occur along the lingual side of the mandible.

Occurrences of tori are more frequent in women than in men. Tori are associated with adulthood and rarely appear before the age of 15. The palatal version of tori have a higher occurrence in Native American and Inuit populations.

Treatment is not necessary unless they become an obstruction to chewing or prosthetic appliances.

Torus mandibularis "(pl. tori mandibulares)" (or mandibular torus "(pl. mandibular tori)" in English) is a bony growth in the mandible along the surface nearest to the tongue. Mandibular tori are usually present near the premolars and above the location of the mylohyoid muscle's attachment to the mandible. In 90% of cases, there is a torus on both the left and right sides, making this finding a predominantly bilateral condition.

The prevalence of mandibular tori ranges from 5% - 40%. It is less common than bony growths occurring on the palate, known as torus palatinus. Mandibular tori are more common in Asian and Inuit populations, and slightly more common in males. In the United States, the prevalence is 7% - 10% of the population.

It is believed that mandibular tori are caused by several factors. They are more common in early adult life and are associated with bruxism. The size of the tori may fluctuate throughout life, and in some cases the tori can be large enough to touch each other in the midline of mouth. Consequently, it is believed that mandibular tori are the result of local stresses and not due solely to genetic influences.

Mandibular tori are usually a clinical finding with no treatment necessary. It is possible for ulcers to form in the area of the tori due to trauma. The tori may also complicate the fabrication of dentures. If removal of the tori is needed, surgery can be done to reduce the amount of bone, but the tori may reform in cases where nearby teeth still receive local stresses.

Torus palatinus "(pl. tori palatini)" [palatinus torus "(pl. palatal tori)" in English] is a bony protrusion on the palate. Palatal tori are usually present on the midline of the hard palate. Most palatal tori are less than 2 cm in diameter, but their size can change throughout life.

Prevalence of palatal tori ranges from 9–60% and are more common than bony growths occurring on the mandible, known as torus mandibularis. Palatal tori are more common in Asian, Native American and Inuit populations, and twice more common in females. In the United States, the prevalence is 20% - 35% of the population with similar findings between black and white people.

Although some research suggest palatal tori to be an autosomal dominant trait, it is generally believed that palatal tori are caused by several factors. They are more common in early adult life and can increase in size. In some older people, the size of the tori may decrease due to bone resorption. It is believed that tori of the lower jaw are the result of local stresses and not solely on genetic influences.

Sometimes, the tori are categorized by their appearance. Arising as a broad base and a smooth surface, flat tori are located on the midline of the palate and extend symmetrically to either side. Spindle tori have a ridge located at their midline. Nodular tori have multiple bony growths that each have their own base. Lobular tori have multiple bony growths with a common base.

Palatal tori are usually a clinical finding with no treatment necessary. It is possible for ulcers to form on the area of the tori due to repeated trauma. Also, the tori may complicate the fabrication of dentures. If removal of the tori is needed, surgery can be done to reduce the amount of bone present.

Since alveolar osteitis is not primarily an infection, there is not usually any pyrexia (fever) and cervical lymphadenitis (swollen glands in the neck), and only minimal edema (swelling) and erythema (redness) is present in the soft tissues surrounding the socket.

Signs may include:

- An empty socket, which is partially or totally devoid of blood clot. Exposed bone may be visible or the socket may be filled with food debris which reveals the exposed bone once it is removed. The exposed bone is extremely painful and sensitive to touch. Surrounding inflamed soft tissues may overlie the socket and hide the dry socket from casual examination.

- Denuded (bare) bone walls.

Symptoms may include:

- Dull, aching, throbbing pain in the area of the socket, which is moderate to severe and may radiate to other parts of the head such as the ear, eye, temple and neck. The pain normally starts on the second to fourth day after the extraction, and may last 10–40 days. The pain may be so strong that even strong analgesics do not relieve it.

- Intraoral halitosis (oral malodor).

- Bad taste in the mouth.

A maxillary torus is only removed in instances where it is problematic. This includes cases where in an edentulous patient, it extends to the vibrating line, preventing a posterior seal of the denture and posterior seal at the fovea palatinae. Other indications for removal include frequent trauma to the torus, owing to its size or the thinness of the mucoperiosteum overlying it, disturbance of speech, and rapid growth in patients who are cancer-phobic.

In the initial phase of the disease, the mucosa feels leathery with palpable fibrotic bands. In the advanced stage the oral mucosa loses its resiliency and becomes blanched and stiff. The disease is believed to begin in the posterior part of the oral cavity and gradually spread outward.

Other features of the disease include:

- Xerostomia

- Recurrent ulceration

- Pain in the ear or deafness

- Nasal intonation of voice

- Restriction of the movement of the soft palate

- A budlike shrunken uvula

- Thinning and stiffening of the lips

- Pigmentation of the oral mucosa

- Dryness of the mouth and burning sensation

- Decreased mouth opening and tongue protrusion

While identifying the causes of tongue thrust, it is important to remember that the resting posture of the tongue, jaw, and lips are crucial to normal development of mouth and its structures. If tongue rests against the upper front teeth, the teeth may protrude forward, and adverse tongue pressure can restrict the development of the oral cavity. The tongue lies low in the mouth or oral cavity and is typically forwarded between upper and lower teeth. If tongue thrust behavior is not corrected, it may affect the normal dental development. The teeth may be pushed around in different directions during the growth of permanent teeth.

Since dry socket occurs exclusively following a dental extraction, it could be considered both a complication and an iatrogenic condition, but this does not take into account both the reason why the tooth required extraction (i.e., extraction may have been unavoidable due to significant pain and infection) and also the fact that many dry sockets are the result of poor compliance with postoperative instructions, notably refraining from smoking in the days immediately after the procedure.

A ranula usually presents as a translucent blue, dome-shaped, swelling in the tissues of the floor of the mouth. If the lesion is deeper, then there is a greater thickness of tissue separating from the oral cavity and the blue translucent appearance may not be a feature. A ranula can develop into a large lesion many centimeters in diameter, with resultant elevation of the tongue and possibly interfering with swallowing (dysphagia). The swelling is not fixed, may not show blanching and is non-painful unless it becomes secondarily infected. The usual location is usually lateral to the midline, which may be used to help distinguish it from a midline dermoid cyst. A cervical ranula presents as a swelling in the neck, with or without a swelling in the mouth. In common with other mucoceles, ranulas may rupture and then cause recurrent swelling. Ranulas may be asymptomatic, although they can fluctuate rapidly in size, shrinking and swelling, making them hard to detect.

OMD refers to abnormal resting posture of the orofacial musculature, atypical chewing, and swallowing patterns, dental malocclusions, blocked nasal airways, and speech problems. OMD are patterns involving oral and/orofacial musculature that interferes with normal growth, development, or function of structures, or calls attention to itself. OMD are found in both children and adults. OMD that are commonly seen in children include tongue thrust that is also known as swallowing with an anterior tongue posture. OMD also refers to factors such as nonnutritive sucking behaviors, such as thumb sucking, clenching, bruxing, etc. that led to abnormal development of dentition and oral cavity. OMD in adult and geriatric population are due to various neurological impairments, oral hygiene, altered functioning of muscles due to aging, systemic diseases, etc.

Tongue thrusting is a type of orofacial myofunctional disorder, which is defined as habitual resting or thrusting the tongue forward and/or sideways against or between the teeth while swallowing, chewing, resting, or speaking. Abnormal swallowing patterns push the upper teeth forward and away from the upper alveolar processes and cause open bites. In children, tongue thrusting is common due to immature oral behavior, narrow dental arch, prolonged upper respiratory tract infections, spaces between the teeth (diastema), muscle weakness, malocclusion, abnormal sucking habits, and open mouth posture due to structural abnormalities of genetic origin. Large tonsils and adenoids also contribute to tongue thrust swallowing.

From the dental perspective, teeth move in relation to the balance of the soft tissue; the normal relationship of teeth lies in occlusion; and any deviation from the normal occlusion can lead to dental distress. Tongue posture plays an important role in swallowing and dentofacial growth. In case of tongue thrust swallowing, the tip of the tongue can come against or between the dentition; the midpoint may be collapsed or extended unilaterally or bilaterally; or the posterior part of the hard palate. In these conditions, there are chances of abnormal dentofacial growth and other concerns regarding development of the craniofacial complex.

There are pertinent symptomatic questions that can be considered for the diagnosis of tongue thrust swallow. Some of these questions are geared toward tongue protrusion and an opening of lips when the client is in repose; habitual mouth breathing; digit sucking; existence of high and narrow palatal arch; ankyloglossia (tongue-tie); malocclusions, (Class II, III); weak chewing muscles (masseter); weak lip muscles (orbicularis oris); overdeveloped chin muscles (mentalis); muscular imbalance; abnormal dentition.

Tongue thrusting and speech problems may co-occur. Due to unconventional postures of the tongue and other articulators, interdental and frontal lisping are very common. The alveolar sounds /s/ and /z/ are produced more anteriorly thus leading to interdental fricative like sounds, /th/.

Formation on the lower jaw occurs much less commonly than on the upper jaw. They are painless and have no risk of turning into cancer, although they may slowly expand over years, or sometimes more rapidly.

Hair abnormalities are very prominent in majority of the cases of TDO. Kinky/curly hair that is unusually dry and easily sheds is present at birth. In 80% of cases, the hair has a more relaxed appearance by adolescence. The presence of this hair texture type is a defining characteristic between a diagnosis of TDO verses amelogenesis imperfecta with hypomaturation. Additionally, in TDO the nails are usually abnormally thin, brittle, and split frequently. Cranial deficiencies are marked by the presence of having a long skull relative to its width, or protrusive foreheads due to increased thickness of the cranial bones and premature closing of the associated sutures in the skull. The long bones in the body (arms, legs) are also abnormally long and tend to fracture very easily. Osteosclerosis, commonly seen in TDO cases is characterized by an increase in bone density, affecting the skull and the mastoid process located behind the jawbone on the skull, as well as a shortened ramus seen in people with TDO. There are no known pathological problems associated with hair and bone changes in people with this disease. Changes in the long bones tend to appear later in development, but changes in the teeth appear once the teeth being to form, called primary dentition. The hair and bone abnormalities are evaluated radiographically during initial diagnosis, and visually during the course of the disease. Radiographic exams may be repeated if there is suspect of fracture.

Buccal exostoses are considered different entities to osteomas (e.g. seen in Gardner syndrome), even though the two lesions are histopathologically identical.

The fluid within a ranula has the viscous, jellylike consistency of egg white.

In the oral cavity 100% of people diagnosed with TDO have taurodontism which is characterized by vertically enlarged pulp chambers at the expense of the roots of the teeth; the floor of the pulp chamber and furcation is moved apically down. This is due to the failure of the Hertwig epithelial root sheath which maps the shape of the forming tooth roots during active differentiation. Amelogenesis imperfecta, an abnormal formation of the enamel or external layer of the crown of the tooth, may also be present where the tooth enamel may be thin or absent. There are several clinical subsets of amelogenesis imperfecta, but common to TDO is the hypoplastic-hypomaturation subtype; the hypomaturation-hypoplastic is less common in individuals with TDO. The difference between the 2 dominant subtypes is the changes seen in the enamel matrix, and the phenotypic type that predominates. The hypoplastic-hypomaturation type of amelogenesis imperfecta with TDO occurs where the tooth enamel depicts a generalized pitted pattern, with open contacts between the teeth as well as an open bite. A smaller amount of cases are of the hypomaturation-hypoplastic case type, in which the enamel structure is softer due to the under maturation of ameloblasts during development. Mandibular prognathism also called a severe underbite, is also a prominent feature in TDO. Prognathism defects are diagnosed based the level of severity that this condition interferes with being able to chew or speak properly.

Due to improper tooth development, TDO patients suffer from high rates of dental caries causing dental abscess. The under maturation of the enamel causes the tooth structure to be softer, and more susceptible to the effects of bruxism due to abnormalities in skeletal development. The oral abnormalities are evaluated by radiographs and visual examination. Oral radiographs are frequently repeated due to the high incidence of infection due to abnormal biting patterns seen in TDO cases.

Hairy tongue largely occurs in the central part of the dorsal tongue, just anterior (in front) of the circumvallate papillae, although sometimes the entire dorsal surface may be involved. Discoloration usually accompanies hairy tongue, and may be yellow, brown or black. Apart from the appearance, the condition is typically asymptomatic, but sometimes people may experience a gagging sensation or a bad taste. There may also be associated oral malodor (intra-oral halitosis).

A great many diseases involve the mouth, jaws and orofacial skin. Some example pathologies which can involve the oral and maxillofacial region are listed. Some are more common than others, and this list is by no means complete. The examples are considered according to a surgical sieve.

Oral and maxillofacial pathology (also termed oral pathology, stomatognathic disease, dental disease, or mouth disease) refers to the diseases of the mouth ("oral cavity" or "stoma"), jaws ("maxillae" or "gnath") and related structures such as salivary glands, temporomandibular joints, facial muscles and perioral skin (the skin around the mouth). The mouth is an important organ with many different functions. It is also prone to a variety of medical and dental disorders.

The specialty oral and maxillofacial pathology is concerned with diagnosis and study of the causes and effects of diseases affecting the oral and maxillofacial region. It is sometimes considered to be a specialty of dentistry and pathology. Sometimes the term head and neck pathology is used instead, but this might imply that the pathologist deals with otorhinolaryngologic disorders (i.e. ear, nose and throat) in addition to maxillofacial disorders. In this role there is some overlap between the expertise of head and neck pathologists and that of endocrine pathologists.

There is a diffuse, gray-white, milky opalescent appearance of the mucosa which usually occurs bilaterally on the buccal mucosa. Less often, the labial mucosa, the palate or the floor of mouth may be affected. The surface of the area is folded, creating a wrinkled, white streaked lesion. Apart from the appearance, the lesion is entirely asymptomatic.

Oral submucous fibrosis (OSMF or OSF) is a chronic, complex, premalignant (1% transformation risk) condition of the oral cavity, characterized by juxta-epithelial inflammatory reaction and progressive fibrosis of the submucosal tissues (the lamina propria and deeper connective tissues). As the disease progresses, the jaws become rigid to the point that the person is unable to open the mouth. The condition is remotely linked to oral cancers and is associated with areca nut or betel quid chewing, a habit similar to tobacco chewing, is practiced predominantly in Southeast Asia and India, dating back thousands of years.

True hyposalivation may give the following signs and symptoms:

- Dental caries (xerostomia related caries) – Without the anticariogenic actions of saliva, tooth decay is a common feature and may progress much more aggressively than it would otherwise ("rampant caries"). It may affect tooth surfaces that are normally spared, e.g., cervical caries and root surface caries. This is often seen in patients who have had radiotherapy involving the major salivary glands, termed radiation-induced caries.

- Acid erosion. Saliva acts as a buffer and helps to prevent demineralization of teeth.

- Oral candidiasis – A loss of the antimicrobial actions of saliva may also lead to opportunistic infection with "Candida" species.

- Ascending (suppurative) sialadenitis – an infection of the major salivary glands (usually the parotid gland) that may be recurrent. It is associated with hyposalivation, as bacteria are able to enter the ductal system against the diminished flow of saliva. There may be swollen salivary glands even without acute infection, possibly caused by autoimmune involvement.

- Dysgeusia – altered taste sensation (e.g., a metallic taste) and dysosmia, altered sense of smell.

- Intraoral halitosis – possibly due to increased activity of halitogenic biofilm on the posterior dorsal tongue (although dysgeusia may cause a complaint of nongenuine halitosis in the absence of hyposalivation).

- Oral dysesthesia – a burning or tingling sensation in the mouth.

- Saliva that appears thick or ropey.

- Mucosa that appears dry.

- A lack of saliva pooling in the floor of the mouth during examination.

- Dysphagia – difficulty swallowing and chewing, especially when eating dry foods. Food may stick to the tissues during eating.

- The tongue may stick to the palate, causing a clicking noise during speech, or the lips may stick together.

- Gloves or a dental mirror may stick to the tissues.

- Fissured tongue with atrophy of the filiform papillae and a lobulated, erythematous appearance of the tongue.

- Saliva cannot be "milked" (expressed) from the parotid duct.

- Difficulty wearing dentures, e.g., when swallowing or speaking. There may be generalized mucosal soreness and ulceration of the areas covered by the denture.

- Mouth soreness and oral mucositis.

- Lipstick or food may stick to the teeth.

- A need to sip drinks frequently while talking or eating.

- Dry, sore, and cracked lips and angles of mouth.

- Thirst.

However, sometimes the clinical findings do not correlate with the symptoms experienced. E.g., a person with signs of hyposalivation may not complain of xerostomia. Conversely a person who reports experiencing xerostomia may not show signs of reduced salivary secretions (subjective xerostomia). In the latter scenario, there are often other oral symptoms suggestive of oral dysesthesia ("burning mouth syndrome"). Some symptoms outside the mouth may occur together with xerostomia.

These include:

- Xerophthalmia (dry eyes).

- Inability to cry.

- Blurred vision.

- Photophobia (light intolerance).

- Dryness of other mucosae, e.g., nasal, laryngeal, and/or genital.

- Burning sensation.

- Itching or grittiness.

- Dysphonia (voice changes).

There may also be other systemic signs and symptoms if there is an underlying cause such as Sjögren's syndrome, for example, joint pain due to associated rheumatoid arthritis.

Hairy tongue (lingua villosa) refers to a marked accumulation of keratin on the filiform papillae on the dorsal surface of the tongue, giving a hair-like appearance. Black tongue (lengua negra) refers to a black discoloration of the tongue, which may or may not be associated with hairy tongue. However, the elongated papillae of hairy tongue usually develop discoloration due to growth of pigment producing bacteria and staining from food. Hence the term black hairy tongue, although hairy tongue may also be discolored yellow or brown. Transient, surface discoloration that is not associated with hairy tongue can be brushed off. Drug-induced black hairy tongue specifically refers to BHT that develops because of medication.

Early Childhood Caries (ECC), formerly known as nursing bottle caries, baby bottle tooth decay, night bottle mouth and night bottle caries, is a disease that affects teeth in children aged between birth and 71 months. ECC is characterized by the presence of 1 or more decayed (noncavitated or cavitated lesions), missing (due to caries), or filled tooth surfaces in any primary tooth. ECC has been shown to be a very common, transmissible bacterial infection, usually passed from the primary caregiver to the child. The main bacteria responsible for dental caries is Streptococcus mutans (S. Mutans) and Lactobacillus. There is also evidence that supports that those who are in lower socioeconomic populations are at greater risk of developing ECC.

By definition, BMS has no signs. Sometimes affected persons will attribute the symptoms to sores in the mouth, but these are in fact normal anatomic structures (e.g. lingual papillae, varices). Symptoms of BMS are variable, but the typical clinical picture is given below, considered according to the Socrates pain assessment method (see table). If clinical signs are visible, then another explanation for the burning sensation may be present. Erythema (redness) and edema (swelling) of papillae on the tip of the tongue may be a sign that the tongue is being habitually pressed against the teeth. The number and size of filiform papillae may be reduced. If the tongue is very red and smooth, then there is likely a local or systemic cause (e.g. eythematous candidiasis, anemia).

In health, the dorsal surface of the tongue is covered in tuft like projections called lingual papillae (some of which are associated with taste buds), which give the tongue an irregular surface texture and a white-pink color. Geographic tongue is characterized by areas of atrophy and depapillation (loss of papillae), leaving an erythematous (darker red) and smoother surface than the unaffected areas. The depapillated areas are usually well demarcated, and bordered by a slightly raised, white, yellow or grey, serpiginous (snaking) peripheral zone. A lesion of geographic tongue may start as a white patch before the depapillation occurs. In certain cases there may be only one lesion, but this is uncommon; the lesions will typically occur in multiple locations on the tongue and coalesce over time to form the typical map-like appearance. The lesions usually change in shape, size and migrate to other areas, sometimes within hours. The condition may affect only part of the tongue, with a predilection for the tip and the sides of the tongue, or the entire dorsal surface at any one time. The condition goes through periods of remission and relapse. Loss of the white peripheral zone is thought to signify periods of mucosal healing.

There are usually no symptoms other than the unusual appearance of the tongue, but in some cases persons may experience pain or burning e.g. when eating hot, acidic, spicy or other kinds of foods (e.g. cheese, tomatoes, fruit). Where there is a burning symptom, other causes of a burning sensation on the tongue are considered, such as oral candidiasis.