Usual diagnosis is via radiograph, patient history, biopsy is rarely needed. Periodic follow ups should included additional radiographs that show minimal growth or regression.

Osteonecrosis of the jaw is classified based on severity, number of lesions, and lesion size. Osteonecrosis of greater severity is given a higher grade, with asymptomatic ONJ designated as grade 1 and severe ONJ as grade 4.

The treatment should be tailored to the cause involved and the severity of the disease process. With oral osteoporosis the emphasis should be on good nutrient absorption and metabolic wastes elimination through a healthy gastro-intestinal function, effective hepatic metabolism of toxicants such as exogenous estrogens, endogenous acetaldehyde and heavy metals, a balanced diet, healthy lifestyle, assessment of factors related to potential coagulopathies, and treatment of periodontal diseases and other oral and dental infections.

In cases of advanced oral ischaemic osteoporosis and/or ONJ that are not bisphosphonates related, clinical evidence has shown that surgically removing the damaged marrow, usually by curettage and decortication, will eliminate the problem (and the pain) in 74% of patients with jaw involvement. Repeat surgeries, usually smaller procedures than the first, may be required. Almost a third of jawbone patients will need surgery in one or more other parts of the jaws because the disease so frequently present multiple lesions, i.e., multiple sites in the same or similar bones, with normal marrow in between. In the hip, at least half of all patients will get the disease in the opposite hip over time; this pattern occurs in the jaws as well. Recently, it has been found that some osteonecrosis patients respond to anticoagulation therapies alone. The earlier the diagnosis the better the prognosis. Research is ongoing on other non-surgical therapeutic modalities that could alone or in combination with surgery further improve the prognosis and reduce the morbidity of ONJ. A greater emphasis on minimizing or correcting known causes is necessary while further research is conducted on chronic ischaemic bone diseases such as oral osteoporosis and ONJ.

In patients with bisphosphonates-associated ONJ, the response to surgical treatment is usually poor. Conservative debridement of necrotic bone, pain control, infection management, use of antimicrobial oral rinses, and withdrawal of bisphosphonates are preferable to aggressive surgical measures for treating this form of ONJ. Although an effective treatment for bisphosphonate-associated bone lesions has not yet been established, and this is unlikely to occur until this form of ONJ is better understood, there have been clinical reports of some improvement after 6 months or more of complete cessation of bisphosphonate therapy.

Computed tomography is the most sensitive and specific of the imaging techniques. The facial bones can be visualized as slices through the skeletal in either the axial, coronal or sagittal planes. Images can be reconstructed into a 3-dimensional view, to give a better sense of the displacement of various fragments. 3D reconstruction, however, can mask smaller fractures owing to volume averaging, scatter artifact and surrounding structures simply blocking the view of underlying areas.

Research has shown that panoramic radiography is similar to computed tomography in its diagnostic accuracy for mandible fractures and both are more accurate than plain film radiograph. The indications to use CT for mandible fracture vary by region, but it does not seem to add to diagnosis or treatment planning except for comminuted or avulsive type fractures, although, there is better clinician agreement on the location and absence of fractures with CT compared to panoramic radiography.

There are various classification systems of mandibular fractures in use.

A related condition, bisphosphonate-associated osteonecrosis of the jaw (BON), has been described as a side-effect of amino-bisphosphonates, a class of phosphorus-based drugs that inhibit bone resorption and are used widely for treating osteoporosis, bone disease in cancer and some other conditions.

BON, sometimes called "bis-phossy jaw",

is primarily associated with the use of intravenous bisphosphonates in the treatment of cancer. The percentage incidence of BON from this use is approximately 1000 times higher than the incidence of BON caused by the use of oral bisphosphonates.

Well defined, rounded or triangular radiodensity, that is uniformly opaque. There is no lucent component. Found near the root apex or in the inter-radicular area. Root resorption and tooth movement are rare.

Generally buccal exostoses require no treatment. However, they may be easily traumatized causing ulceration, or may contribute to periodontal disease if they become too large, or can interfere with wearing a denture (false teeth). If they are creating problems, they are generally removed with a simple surgical procedure under local anesthetic.

Radium jaw is an occupational disease brought on by the ingestion and subsequent absorption of radium into the bones of radium dial painters and those consuming radium-laden patent medicines. The symptoms are necrosis of the mandible (lower jawbone) and the maxilla (upper jaw), constant bleeding of the gums, and (usually) after some time, severe distortion due to bone tumors and porosity of the lower jaw.

The condition is similar to phossy jaw, an osteoporitic and osteonecrotic illness of matchgirls, brought on by phosphorus ingestion and absorption. The first written reference to the disease was by a dentist, Dr. Theodor Blum (1924), who described an unusual mandibular osteomyelitis in a dial painter, naming it radium jaw".

The disease was determined by Dr. H.S. Martland in 1924 to be symptomatic of radium paint ingestion, after many female workers from various radium paint companies reported similar dental and mandibular pain. Symptoms were present in the mouth due to use of the lips and tongue to keep the radium-paint paintbrushes properly shaped. The disease was the main reason for litigation against the United States Radium Corporation by the Radium Girls.

Another prominent example of this condition was the death of American golfer and industrialist Eben Byers in 1932, after taking large doses of Radithor, a radioactive patent medicine containing radium, over several years. His illness garnered much publicity, and brought the problem of radioactive quack medicines into the public eye. "The Wall Street Journal" ran a story (in 1989 or after) titled "The Radium Water Worked Fine until His Jaw Came Off",

Crowding of the teeth is treated with orthodontics, often with tooth extraction, clear aligners, or dental braces, followed by growth modification in children or jaw surgery (orthognathic surgery) in adults. Surgery may be required on rare occasions. This may include surgical reshaping to lengthen or shorten the jaw (orthognathic surgery). Wires, plates, or screws may be used to secure the jaw bone, in a manner similar to the surgical stabilization of jaw fractures. Very few people have "perfect" alignment of their teeth. However, most problems are very minor and do not require treatment.

Phossy jaw, formally phosphorus necrosis of the jaw, is an occupational disease of those who work with white phosphorus, also known as "yellow phosphorus", without proper safeguards. It was most commonly seen in workers in the match-stick industry in the 19th and early 20th century. Modern occupational hygiene practices have eliminated the working conditions which caused this disease. This disease is caused by the vapour of white phosphorus, which destroys the bones of the jaw.

To establish appropriate alignment and occlusion, the sizes of upper and lower front teeth, or upper and lower teeth in general, need to be proportional. Inter-arch tooth size discrepancy (TSD) is defined as a disproportion in the mesio-distal dimensions of teeth of opposing dental arches, which can be seen in 17% to 30% of orthodontic patients.

In disease states, maxillary prognathism is associated with Cornelia de Lange syndrome; however, so-called false maxillary prognathism, or more accurately, retrognathism, where there is a lack of growth of the mandible, is by far a more common condition.

Prognathism, if not extremely severe, can be treated in growing patients with orthodontic functional or orthopaedic appliances. In adult patients this condition can be corrected by means of a combined surgical/orthodontic treatment, where most of the time a mandibular advancement is performed. The same can be said for mandibular prognathism.

They are more common in males than females, occurring in a ratio of about 5:1. They are strongly associated with the presence of torus mandibularis and torus palatinus.

Treatment of condylar resorption is controversial. Orthognathic surgery may be done to reconstruct and stabilize the condyles and disc of the temporomandibular joint. Anti-infammatory medication is also used to slow the resorption process. Orthodontics may be used to treat the occlusion. Arthrocentesis, and arthroscopic surgery are also sometimes used to treat disc displacement and other symptoms.

Brachygnathism or colloquially Parrot Mouth, is the uneven alignment of the upper and lower teeth in horses. In serious cases, the upper teeth protrude beyond the lower teeth. Problem with parrot mouth occur if the molars at the back of the mouth are also uneven, resulting in large hooks forming on the upper molars and the rear of the lower back molars. Horses with parrot mouth often require dental treatment at least every six months to remove the hooks and maintain alignment.

The equivalent conditions in humans are termed retrognathism or prognathism depending on whether the lower jaw is too far back or too far forward respectively.

Prognathism is the positional relationship of the mandible or maxilla to the skeletal base where either of the jaws protrudes beyond a predetermined imaginary line in the coronal plane of the skull. In general dentistry, oral and maxillofacial surgery and orthodontics, this is assessed clinically or radiographically (cephalometrics). The word "prognathism" derives from Greek "pro" ("forward") and γνάθος "gnáthos" ("jaw"). One or more types of prognathism may result in the common condition of malocclusion, in which an individual's top teeth and lower teeth do not align properly.

Dilaceration is a developmental disturbance in shape of teeth. It refers to an angulation, or a sharp bend or curve, in the root or crown of a formed tooth.

The precise frequency of pycnodysostosis has not been determined. Pycnodysostosis can be classified in the large group of genetic diseases that are individually uncommon, but collectively important because of the sum of their numbers, and their heavy impact upon affected individuals.

Cavitations are an area of dead bone caused by a dearth of blood flow to that part of the bone. A cavitation is a hole in the blood vessel that cannot be visually detected with the naked eye. Jawbone cavitations, also called neuralgia-inducing cavitational osteonecrosis (NICO) if they are associated with pain, are extraction sites in the jaw that have not healed.

The initial evaluation involves radiographs (X-rays) of the affected site, but the only way to confirm the diagnosis is by sampling the tissue via biopsy or needle aspiration.

Pycnodysostosis (from Greek: πυκνός (puknos) meaning "dense", "dys" ("defective"), and "ostosis" ("condition of the bone")), is a lysosomal storage disease of the bone caused by a mutation in the gene that codes the enzyme cathepsin K.

The condition is thought to be due to trauma or possibly a delay in tooth eruption relative to bone remodeling gradients during the period in which tooth is forming. The result is that the position of the calcified portion of the tooth is changed and the remainder of the tooth is formed at an angle.

The curve or bend may occur anywhere along the length of the tooth, sometimes at the cervical portion, at other times midway along the root or even just at the apex of the root, depending upon the amount of root formed when the injury occurred.

Such an injury to a permanent tooth, resulting in dilaceration, often follows traumatic injury to the deciduous predecessor in which that tooth is driven apically into the jaw.

Craniomandibular osteopathy, also known as lion's jaw, is a developmental disease in dogs causing extensive bony changes in the mandible and skull. In this disease, a cyclical resorption of normal bone and replacement by immature bone occurs along the inner and outer surfaces of the affected bones. It usually occurs between the ages of 3 and 8 months. Breeds most commonly affected include the West Highland White Terrier, Scottish Terrier, Cairn Terrier, and Boston Terrier. It is rare in large-breed dogs, but it has been reported. Symptoms include firm swelling of the jaw, drooling, pain, and difficulty eating.

It is an inherited disease, especially in Westies, in which it has been recognized as an autosomal recessive trait. Canine distemper has also been indicated as a possible cause, as has "E. coli" infection, which could be why it is seen occasionally in large-breed dogs. Growth of lesions will usually stop around the age of one year, and possibly regress. This timing coincides with the normal completion of endochondral bone growth and ossification. If the disease is extensive, especially around the tympanic bulla (middle ear), then the prognosis is guarded.

A similar disease seen in young Bullmastiffs is known as calvarial hyperostotic syndrome. It is also similar to human infantile cortical hyperostosis. It is characterized by irregular, progressive bony proliferation and thickening of the cortical bone of the calvaria, which is part of the skull. Asymmetry of the lesions may occur, which makes it different from craniomandibular osteopathy. Symptoms include painful swelling of the skull, fever, and lymph node swelling. In most cases it is self-limiting.

A diastema (plural diastemata) is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. Diastemata are common for children and can exist in adult teeth as well. Diastemata are primarily caused by imbalance in the relationship between the jaw and the size of teeth. If the labial frenulum (lip tissue) pulls, it can also push the teeth apart and cause a diastema between the center of the two front teeth.