Other factors such as toxicants can adversely impact bone cells. Infections, chronic or acute, can affect blood flow by inducing platelet activation and aggregation, contributing to a localized state of excess coagulability (hypercoagulability) that may contribute to clot formation (thrombosis), a known cause of bone infarct and ischaemia. Exogenous estrogens, also called hormonal disruptors, have been linked with an increased tendency to clot (thrombophilia) and impaired bone healing.

Heavy metals such as lead and cadmium have been implicated in osteoporosis. Cadmium and lead promotes the synthesis of plasminogen activator inhibitor-1 (PAI-1) which is the major inhibitor of fibrinolysis (the mechanism by which the body breaks down clots) and shown to be a cause of hypofibrinolysis. Persistent blood clots can lead to congestive blood flow (hyperemia) in bone marrow, impaired blood flow and ischaemia in bone tissue resulting in lack of oxygen (hypoxia), bone cell damage and eventual cell death (apoptosis). Of significance is the fact that the average concentration of cadmium in human bones in the 20th century has increased to about 10 times above the pre-industrial level.

The first three cases of bisphosphonate-associated osteonecrosis of the jaw were spontaneously reported to the FDA by an oral surgeon in 2002, with the toxicity being described as a potentially late toxicity of chemotherapy. In 2003 and 2004, three oral surgeons independently reported to the FDA information on 104 cancer patients with bisphosphonate-associated osteonecrosis of the jaw seen in their referral practices in California, Florida, and New York. These case series were published as peer-reviewed articles — two in the "Journal of Oral and Maxillofacial Surgery" and one in the "Journal of Clinical Oncology". Subsequently, numerous instances of persons with this ADR were reported to the manufacturers and to the FDA. By December 2006, 3607 cases of people with this ADR had been reported to the FDA and 2227 cases had been reported to the manufacturer of intravenous bisphosphonates.

The International Myeloma Foundation's web-based survey included 1203 respondents, 904 patients with myeloma and 299 with breast cancer and an estimate that after 36 months, osteonecrosis of the jaw had been diagnosed in 10% of 211 patients on zoledronate and 4% of 413 on pamidronate. A population based study in Germany identified more than 300 cases of osteonecrosis of the jaw, 97% occurring in cancer patients (on high-dose intravenous bisphosphonates) and 3 cases in 780,000 patients with osteoporosis for an incidence of 0.00038%. Time to event ranged from 23–39 months and 42–46 months with high dose intravenous and oral bisphosphonates. A prospective, population based study by Mavrokokki "et al.". estimated an incidence of osteonecrosis of the jaw of 1.15% for intravenous bisphosphonates and 0.04% for oral bisphosphonates. Most cases (73%) were precipitated by dental extractions. In contrast, safety studies sponsored by the manufacturer reported bisphosphonate-associated osteonecrosis of the jaw rates that were much lower.

Although the majority of cases of ONJ have occurred in cancer patients receiving high dose intravenous bisphosphonates, almost 800 cases have been reported in oral bisphosphonate users for osteoporosis or Pagets disease. In terms of severity most cases of ONJ in oral bisphosphonate users are stage 1–2 and tend to progress to resolution with conservative measures such as oral chlorhexidine rinses.

Owing to prolonged embedding of bisphosphonate drugs in the bone tissues, the risk for BRONJ is high even after stopping the administration of the medication for several years.

This form of therapy has been shown to prevent loss of bone mineral density (BMD) as a result of a reduction in bone turnover. However, bone health entails quite a bit more than just BMD. There are many other factors to consider.

In healthy bone tissue there is a homeostasis between bone resorption and bone apposition. Diseased or damaged bone is resorbed through the osteoclasts mediated process while osteoblasts form new bone to replace it, thus maintaining healthy bone density. This process is commonly called remodelling.

However, osteoporosis is essentially the result of a lack of new bone formation in combination with bone resorption in reactive hyperemia, related to various causes and contributing factors, and bisphosphonates do not address these factors at all.

In 2011, a proposal incorporating both the reduced bone turnover and the infectious elements of previous theories has been put forward. It cites the impaired functionality of affected macrophages as the dominant factor in the development of ONJ.

In a systematic review of cases of bisphosphonate-associated ONJ up to 2006, it was concluded that the mandible is more commonly affected than the maxilla (2:1 ratio), and 60% of cases are preceded by a dental surgical procedure. According to Woo, Hellstein and Kalmar, oversuppression of bone turnover is probably the primary mechanism for the development of this form of ONJ, although there may be contributing co-morbid factors (as discussed elsewhere in this article). It is recommended that all sites of potential jaw infection should be eliminated before bisphosphonate therapy is initiated in these patients to reduce the necessity of subsequent dentoalveolar surgery. The degree of risk for osteonecrosis in patients taking oral bisphosphonates, such as alendronate (Fosamax), for osteoporosis is uncertain and warrants careful monitoring. Patients taking dexamethasone and other glucocorticoids are at increased risk.

Matrix metalloproteinase 2 may be a candidate gene for bisphosphonate-associated osteonecrosis of the jaw, since it is the only gene known to be associated with bone abnormalities and atrial fibrillation, both of which are side effects of bisphosphonates.

Pathologic fracture of the mandible is a possible complication of OM where the bone has been weakened significantly.

OM of the jaws usually occurs in adult males. The mandible is affected more commonly than the maxilla. The most common cause of OM of the jaws is the spread of adjacent odontogenic infection. The second most common cause is following a fracture, usually of the mandible.

Osteitis is inflammation of bone. More specifically, it can refer to one of the following conditions:

- Osteomyelitis, or "infectious osteitis", mainly "bacterial osteitis")

- Alveolar osteitis or "dry socket"

- Condensing osteitis (or Osteitis condensans)

- Osteitis deformans (or Paget's disease of bone)

- Osteitis fibrosa cystica (or Osteitis fibrosa, or Von Recklinghausen's disease of bone)

- Osteitis pubis

- Radiation osteitis

- Osteitis condensans ilii

- Panosteitis, a long bone condition in large breed dogs

- In horses, pedal osteitis is frequently confused with laminitis.

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.

Overall, the incidence of dry socket is about 0.5–5% for routine dental extractions, and about 25–30% for impacted mandibular third molars (wisdom teeth which are buried in the bone).

Females are more frequently affected than males, but this appears to be related to oral contraceptive use rather than any underlying gender predilection. The majority of dry sockets occur in individuals aged between 20 and 40 which is when most dental extractions occur, although for any given individual it is more likely to occur in with increasing age.

Other possible risk factors include periodontal disease, acute necrotizing ulcerative gingivitis, local bone disease, Paget's disease of bone, osteopetrosis, cemento-osseous dysplasia, a history of previously developing a dry socket with past extractions and inadequate oral hygiene. Other factors in the postoperative period that may lead to loss of the blood clot include forceful spitting, sucking through a straw, and coughing or sneezing.

Stafne defect is uncommon, and has been reported to develop anywhere between the ages of 11 and 30 years old, (although the defect is developmental, it does not seem to be present form birth, implying that the lesion develops at a later age). Usually the defect is unilateral (on one side only) and most commonly occurs in men.

Smoking and tobacco use of any kind are associated with increased risk of dry socket. This may be partially due to the vasoconstrictive action of nicotine on small blood vessels. Abstaining from smoking in the days immediately following a dental extraction reduces the risk of a dry socket occurring.

Mandible fracture causes vary by the time period and the region studied. In North America, blunt force trauma (a punch) is the leading cause of mandible fracture whereas in India, motor vehicle collisions are now a leading cause. On battle grounds, it is more likely to be high velocity injuries (bullets and shrapnel). Prior to the routine use of seat belts, airbags and modern safety measures, motor vehicle collisions were a leading cause of facial trauma. The relationship to blunt force trauma explains why 80% of all mandible fractures occur in males. Mandibular fracture is a rare complication of third molar removal, and may occur during the procedure or afterwards. With respect to trauma patients, roughly 10% have some sort of facial fracture, the majority of which come from motor vehicle collisions. When the person is unrestrained in a car, the risk of fracture rises 50% and when an unhelmeted motorcyclist the risk rises 4-fold.

Why buccal exostoses form is unclear, but it may involve bruxism (tooth clenching and grinding), and genetic factors. Typically they first appear in early adulthood.

The healing time for a routine mandible fractures is 4–6 weeks whether MMF or rigid internal fixation (RIF) is used. For comparable fractures, patients who received MMF will lose more weight and take longer to regain mouth opening, whereas, those who receive RIF have higher infection rates.

The most common long-term complications are loss of sensation in the mandibular nerve, malocclusion and loss of teeth in the line of fracture. The more complicated the fracture (infection, comminution, displacement) the higher the risk of fracture.

Condylar fractures have higher rates of malocclusion which in turn are dependent on the degree of displacement and/or dislocation. When the fracture is intracapsular there is a higher rate of late-term osteoarthritis and the potential for ankylosis although the later is a rare complication as long as mobilization is early. Pediatric condylar fractures have higher rates of ankylosis and the potential for growth disturbance.

Rarely, mandibular fracture can lead to Frey's syndrome.

Dentin dysplasia (DD) is a rare genetic developmental disorder dentine production of the teeth, commonly exhibiting an autosomal dominant inheritance that causes malformation of the root. It affects both primary and permanent dentitions in approximately 1 in every 100,000 patients. It is characterized by presence of normal enamel but atypical dentin with abnormal pulpal morphology. Witkop in 1972 classified DD into two types which are Type I (DD-1) is the radicular type, and type II (DD-2) is the coronal type. DD-1 has been further divided into 4 different subtypes (DD-1a,1b,1c,1d) based on the radiographic features.

Diagnosis is mostly based on general examination and radiographs, and it should be taken when abnormality of the teeth is suspected as most of the affected teeth have normal clinical appearance.

Differential diagnosis is very important to have a definitive diagnosis as some radiographic or histologic features of dentine dysplasia may bear a resemblance to different disorders:

- Dentinogenesis Imperfecta

- Odontodysplasia

- Calcinosis

- Osteogenesis imperfecta

- Ehlers Danlos syndrome

- Goldblatt syndrome

- Schimke immuno-osseous dysplasia

- Brachio-skeleto-genital syndrome.

The squamous odontogenic tumor is a rare odontogenic tumor found in any area of the alveolar bone. Usually, there is a painless swelling with adjacent teeth becoming mobile. On radiographs, it presents as a radiolucency (dark area) between the teeth in a triangular shape. Clinically, it may present similar to periodontal disease.

The Stafne defect (also termed Stafne's idiopathic bone cavity, Stafne bone cavity, Stafne bone cyst (misnomer), lingual mandibular salivary gland depression, lingual mandibular cortical defect, latent bone cyst, or static bone cyst) is a depression of the mandible on the lingual surface (the side nearest the tongue). The Stafne defect is thought to be a normal anatomical variant, as the depression is created by ectopic salivary gland tissue associated with the submandibular gland and does not represent a pathologic lesion as such.

A Le Fort fracture of the skull is a classic transfacial fracture of the midface, involving the maxillary bone and surrounding structures in either a horizontal, pyramidal or transverse direction. The hallmark of Lefort fractures is traumatic "pterygomaxillary separation", which signifies fractures between the pterygoid plates, horseshoe shaped bony protuberances which extend from the inferior margin of the maxilla, and the maxillary sinuses. Continuity of this structure is a keystone for stability of the midface, involvement of which impacts surgical management of trauma victims, as it requires fixation to a horizontal bar of the frontal bone. The pterygoid plates lie posterior to the upper dental row, or alveolar ridge, when viewing the face from an anterior view. The fractures are named after French surgeon René Le Fort (1869–1951), who discovered the fracture patterns by examining crush injuries in cadavers.

Tooth ankylosis refers to a fusion (ankylosis) of teeth to bone. The condition is diagnosed with radiographs (X-rays), which show loss of the periodontal ligament space and blending of the root with the bone. Clinically the tooth sounds solid when percussed (tapped) compared to the dull, cushioned sound from normal teeth. Ankylosis of teeth is uncommon, more so in deciduous teeth than permanent teeth.

Dental trauma is most common in younger people, accounting for 17% of injuries to the body in those aged 0–6 years compared to an average of 5% across all ages. It is more frequently observed in males compared to females. Traumatic dental injuries are more common in permanent teeth compared to deciduous teeth and usually involve the front teeth of the upper jaw.

Repair with cementum or dentin occurs after partial root resorption, fusing the tooth with the bone. It may occur following dental trauma, especially occlusal trauma, or after periapical periodontitis caused by pulp necrosis. Ankylosis itself is not a reason to remove a permanent tooth, however teeth which must be removed for other reasons are made significantly more difficult to remove if they are ankylosed.

The prognosis depends upon the type, size and location of a cyst. Most cysts are entirely benign, and some may require no treatment. Rarely, some cystic lesions represent locally aggressive tumors that may cause destruction of surrounding bone if left untreated. This type of cyst are usually removed with a margin of healthy bone to prevent recurrence of new cysts. If a cyst expands to a very large size, the mandible may be weakened such that a pathologic fracture occurs.

Regular use of a mouthguard during sports and other high-risk activities (such as military training) is the most effective prevention for dental trauma. Custom made mouthguard is preferable as it fits well, provides comfort and adequate protection. However, studies in various high-risk populations for dental injuries have repeatedly reported low compliance of individuals for the regular using of mouthguard during activities. Moreover, even with regular use, effectiveness of prevention of dental injuries is not complete, and injuries can still occur even when mouthguards are used as users are not always aware of the best makes or size, which inevitably result in a poor fit.

One of the most important measures is to impart knowledge and awareness about dental injury to those who are involved in sports environments like boxing and in school children in which they are at high risk of suffering dental trauma through an extensive educational campaign including lectures,leaflets,Posters which should be presented in an easy understandable way.

Radicular cysts are by far the most common cyst occurring in the jaws.

Periodontosis is an obsolete term that was used to describe what was once thought to be certain type of unique and distinguishable chronic periodontal disease that manifested as degenerative bony changes without concomitant inflammation. Although utilized for more than 50 years, the term has since been dropped in favor of a more contemporary disease classification for periodontal disease.

Described by Gottlieb as a "diffuse atrophy of the alveolar bone," the term "periodontosis" was later applied and it gained acceptance as a disease entity, being defined as:

Noted as a rare disease, periodontosis was said to have been seen primarily in young patients. And despite being defined as being a "noninflammatory destruction of the periodontium," almost all cases did exhibit varying degrees of gingival inflammation.

Teeth are constantly subject to both horizontal and vertical occlusal forces. With the center of rotation of the tooth acting as a fulcrum, the surface of bone adjacent to the pressured side of the tooth will undergo resorption and disappear, while the surface of bone adjacent to the tensioned side of the tooth will undergo apposition and increase in volume.

In both primary and secondary occlusal trauma, tooth mobility might develop over time, with it occurring earlier and being more prevalent in secondary occlusal trauma. To treat mobility due to primary occlusal trauma, the cause of the trauma must be eliminated. Likewise for teeth subject to secondary occlusal trauma, though these teeth may also require splinting together to the adjacent teeth so as to eliminate their mobility.

In primary occlusal trauma, the cause of the mobility was the excessive force being applied to a tooth with a normal attachment apparatus, otherwise known as a "periodontally-uninvolved tooth". The approach should be to eliminate the cause of the pain and mobility by determining the causes and removing them; the mobile tooth or teeth will soon cease exhibiting mobility. This could involve removing a high spot on a recently restored tooth, or even a high spot on a non-recently restored tooth that perhaps moved into hyperocclusion. It could also involve altering one's parafunctional habits, such as refraining from chewing on pens or biting one's fingernails. For a bruxer, treatment of the patient's primary occlusal trauma could involve selective grinding of certain interarch tooth contacts or perhaps employing a nightguard to protect the teeth from the greater than normal occlusal forces of the patient's parafunctional habit. For someone who is missing enough teeth in non-strategic positions so that the remaining teeth are forced to endure a greater "per square inch" occlusal force, treatment might include restoration with either a removable prosthesis or implant-supported crown or bridge.

In secondary occlusal trauma, simply removing the "high spots" or selective grinding of the teeth will not eliminate the problem, because the teeth are already periodontally involved. After splinting the teeth to eliminate the mobility, the cause of the mobility (in other words, the loss of clinical attachment and bone) must be managed; this is achieved through surgical periodontal procedures such as soft tissue and bone grafts, as well as restoration of edentulous areas. As with primary occlusal trauma, treatment may include either a removable prosthesis or implant-supported crown or bridge.