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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.
Bone lesions in multiple myeloma patients may be treated with low-dose radiation therapy in order to reduce pain and other symptoms. Used in combination with immunochemotherapy, radiation therapy can be used to treat certain cancers when aimed at areas of bone lesion and softened bone.
Biophosphonates are drugs that are used to prevent bone mass loss and are often used to treat osteolytic lesions. Zoledronic acid (Reclast) is a specific drug given to cancer patients to prevent the worsening of bone lesions and has been reported to have anti-tumor effects as well. Zoledronic acid has been clinically tested in conjunction with calcium and vitamin D to encourage bone health. Denosumab, a monoclonal antibody treatment RANKl inhibitor that targets the osteocyte apoptosis regualtory RANKL gene, is also prescribed to prevent bone metastases and bone lesions. Most biophosphonates are co-prescribed with disease-specific treatments, such as chemotherapy or radiation for cancer patients.
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.
Medical management of OFC consists of Vitamin D treatment, generally alfacalcidol or calcitriol, delivered intravenously. Studies have shown that in cases of OFC caused by either end-stage renal disease or primary hyperparathyoidism, this method is successful not only in treating underlying hyperparathyoidism, but also in causing the regression of brown tumors and other symptoms of OFC.
In especially severe cases of OFC, parathyroidectomy, or the full removal of the parathyroid glands, is the chosen route of treatment. Parathyroidectomy has been shown to result in the reversal of bone resorption and the complete regression of brown tumors. In situations where parathyroid carcinoma is present, surgery to remove the tumors has also led to the regression of hyperparathyroidism as well as the symptoms of OFC.
Bone transplants have proven successful in filling the lesions caused by OFC. A report showed that in 8 out of 11 instances where cavities caused by OFC were filled with transplanted bone, the lesion healed and the transplanted bone blended rapidly and seamlessly with the original bone.
Five bisphosphonates are currently available. In general, the most commonly prescribed are risedronic acid, alendronic acid, and pamidronic acid. Etidronic acid and other bisphosphonates may be appropriate therapies for selected patients but are less commonly used. None of these drugs should be used by people with severe kidney disease.
- Etidronate disodium The approved regimen is once daily for six months; a higher dose is more commonly used. No food, beverage, or medications should be consumed for two hours before and after taking. The course should not exceed six months, but repeat courses can be given after rest periods, preferably of three to six months duration.
- Pamidronate disodium in intravenous form: the approved regimen uses an infusion over four hours on each of three consecutive days, but a more commonly used regimen is over two to four hours for two or more consecutive or nonconsecutive days.
- Alendronate sodium is given as tablets once daily for six months; patients should wait at least 30 minutes after taking before eating any food, drinking anything other than tap water, taking any medication, or lying down (patient may sit).
- Tiludronate disodium are taken once daily for three months; they may be taken any time of day, as long as there is a period of two hours before and after resuming food, beverages, and medications.
- Risedronate sodium tablet taken once daily for 2 months is the prescribed regimen; patients should wait at least 30 minutes after taking before eating any food, drinking anything other than tap water, taking any medication, or lying down (patient may sit).
- Zoledronic acid is given as an intravenous infusion; a single dose is effective for two years. This is recommended for most people at high risk with active disease.
Calcitonin, also called calcitonin-salmon, is a synthetic copy of a polypeptide hormone secreted by the ultimobranchial gland of salmon. Miacalcin is administered by injection, three times per week or daily, for 6–18 months. Repeat courses can be given after brief rest periods. Miacalcin may be appropriate for certain patients, but is seldom used. Calcitonin is also linked to increased chance of cancer. Due to the increased risk of cancer, the European Medicines Agency (EMA) recommended that calcitonin be used only on a short-term basis for 3 conditions for which it had previously been approved in the European Union: Paget's disease, acute bone loss resulting from sudden immobilization, and hypercalcemia caused by cancer.
The EMA said it based its recommendations on a review of the benefits and risks of calcitonin-containing medicines. Conducted by the agency's Committee for Medicinal Products for Human Use (CHMP), the review encompassed available data from the companies that market these drugs, postmarketing safety data, randomized controlled studies, 2 studies of unlicensed oral calcitonin drugs, and experimental cancer studies, among other sources.
CHMP found that "a higher proportion of patients treated with calcitonin for long periods of time develop cancer of various types, compared with patients taking placebo." The increase in cancer rates ranged from 0.7% for oral formulations to 2.4% for the nasal formulation. CHMP concluded that the benefits of calcitonin for osteoporosis did not exceed the risks. The nasal spray's only indication is for osteoporosis, thus justifying the drug's removal from the market.
As a solution for injection or infusion, calcitonin should be administered for no more than 4 weeks to prevent acute bone loss resulting from sudden immobilization, and normally for no more than 3 months to treat Paget's disease, the EMA said. The agency did not specify a time frame for the short-term use of calcitonin for treating hypercalcemia caused by cancer.
A variety of methods may be used to treat the most common being the total hip replacement (THR). However, THRs have a number of downsides including long recovery times and short life spans (of the hip joints). THRs are an effective means of treatment in the older population; however, in younger people they may wear out before the end of a person's life.
Other technicques such as metal on metal resurfacing may not be suitable in all cases of avascular necrosis; its suitability depends on how much damage has occurred to the femoral head. Bisphosphonates which reduces the rate of bone breakdown may prevent collapse (specifically of the hip) due to AVN.
Other treatments include core decompression, where internal bone pressure is relieved by drilling a hole into the bone, and a living bone chip and an electrical device to stimulate new vascular growth are implanted; and the free vascular fibular graft (FVFG), in which a portion of the fibula, along with its blood supply, is removed and transplanted into the femoral head. A 2012 Cochrane systematic review noted that no clear improvement can be found between people who have had hip core decompression and participate in physical therapy, versus physical therapy alone. More research is need to look into the effectiveness of hip core decompression for people with sickle cell disease.
Progression of the disease could possibly be halted by transplanting nucleated cells from bone marrow into avascular necrosis lesions after core decompression, although much further research is needed to establish this technique.
The infected tissue of the periapical cyst must be entirely removed, including the epithelium of the cyst wall; otherwise a relapse is likely to occur. Root canal treatment should be performed on the tooth if it is determined that previous therapy was unsuccessful. Removal of the necrotic pulp and the inflamed tissue as well as proper sealing of the canals and an appropriately fitting crown will allow the tooth to heal under uninfected conditions.
Surgical options for previously treated teeth that would not benefit from root canal therapy include cystectomy and cystostomy. This route of treatment is recommended upon discovery of the cyst after inadequate root canal treatment. A cystectomy is the removal of a cyst followed by mucosa and wound closure to reduce chances of cyst regeneration. This type of treatment is more ideal for small cysts.
A cystostomy is recommended for larger cysts that compromise important adjacent anatomy. The cyst is tamponaded to allow for the cyst contents to escape the bone. Over time, the cyst decreases in size and bone regenerates in the cavity space.
Marsupialization could also be performed, which involves suturing the edges of the gingiva surrounding the cyst to remain open. The cyst then drains its contents and heal without being prematurely closed. The end result is the same as the cystostomy, bone regeneration. For both a cystostomy and marsupialization, root resectioning may also be required in cases where root resorption has occurred.
Bisphosphonates are useful in decreasing the risk of future fractures in those who have already sustained a fracture due to osteoporosis. This benefit is present when taken for three to four years. Different bisphosphonates have not been directly compared, therefore it is unknown if one is better than another. Fracture risk reduction is between 25 and 70% depending on the bone involved. There are concerns of atypical femoral fractures and osteonecrosis of the jaw with long-term use, but these risks are low. With evidence of little benefit when used for more than three to five years and in light of the potential adverse events, it may be appropriate to stop treatment after this time. One medical organization recommends that after five years of medications by mouth or three years of intravenous medication among those at low risk, bisphosphonate treatment can be stopped. In those at higher risk they recommend up to ten years of medication by mouth or six years of intravenous treatment.
For those with osteoporosis but who have not had a fracture evidence does not support a reduction in fracture risk with risedronate or etidronate. Alendronate decreases fractures of the spine but does not have any effect on other types of fractures. Half stop their medications within a year. When on treatment with bisphosphonates rechecking bone mineral density is not needed. Another review found tentative evidence of benefit in males with osteoporosis.
Fluoride supplementation does not appear to be effective in postmenopausal osteoporosis, as even though it increases bone density, it does not decrease the risk of fractures.
Teriparatide ( a recombinant parathyroid hormone ) has been shown to be effective in treatment of women with postmenopausal osteoporosis. Some evidence also indicates strontium ranelate is effective in decreasing the risk of vertebral and nonvertebral fractures in postmenopausal women with osteoporosis. Hormone replacement therapy, while effective for osteoporosis, is only recommended in women who also have menopausal symptoms. It is not recommended for osteoporosis by itself. Raloxifene, while effective in decreasing vertebral fractures, does not affect the risk of nonvertebral fracture. And while it reduces the risk of breast cancer, it increases the risk of blood clots and strokes. Denosumab is also effective for preventing osteoporotic fractures but not in males. In hypogonadal men, testosterone has been shown to improve bone quantity and quality, but, as of 2008, no studies evaluated its effect on fracture risk or in men with a normal testosterone levels. Calcitonin while once recommended is no longer due to the associated risk of cancer and questionable effect on fracture risk.
Certain medications like alendronate, etidronate, risedronate, raloxifene and strontium ranelate can be helpful for the preventing of osteoporotic fragility fractures in postmenopausal women with osteoporosis.
Treatment for renal osteodystrophy includes the following:
- calcium and/or native vitamin D supplementation
- restriction of dietary phosphate (especially inorganic phosphate contained in additives)
- phosphate binders such as calcium carbonate, calcium acetate, sevelamer hydrochloride or carbonate, lanthanum carbonate, sucroferric oxyhydroxide, ferric citrate among others
- active forms of vitamin D (calcitriol, alfacalcidol, paricalcitol, maxacalcitol, doxercalciferol, among others)
- cinacalcet
- renal transplantation
- haemodialysis five times a week is thought to be of benefit
- parathyroidectomy for symptomatic medication refractive end stage disease
Treatment of Gorham's disease is for the most part palliative and limited to symptom management.
Sometimes the bone destruction spontaneously ceases and no treatment is required. But when the disease is progressive, aggressive intervention may be necessary. Duffy and colleagues reported that around 17% of patients with Gorham's disease in the ribs, shoulder, or upper spine experience extension of the disease into the chest, leading to chylothorax with its serious consequences, and that the mortality rate in this group can reach as high as 64% without surgical intervention.
A search of the medical literature reveals multiple case reports of interventions with varying rates of success as follows:
Cardiothoracic (heart & lung):
- Pleurodesis
- Ligation of thoracic duct
- Pleurperitoneal shunt
- Radiation therapy
- Pleurectomy
- Surgical resection
- Thalidomide
- Interferon alpha-2b
- TPN (total parenteral nutrition)
- Thoracentesis
- Diet rich in medium-chain triglycerides and protein
- Chemotherapy
- Sclerotherapy
- Transplantation
Skeletal:
- Interferon alpha-2b
- Bisphosphonate (e.g. pamidronate)
- Surgical resection
- Radiation therapy
- Sclerotherapy
- Percutaneous bone cement
- Bone graft
- Prosthesis
- Surgical stabilization
- Amputation
To date, there are no known interventions that are consistently effective for Gorham's and all reported interventions are considered experimental treatments, though many are routine for other conditions. Some patients may require a combination of these approaches. Unfortunately, some patients will not respond to any intervention.
Treatment is usually surgical removal of the gland(s) containing adenomas, but medication may also be required.
Weight-bearing endurance exercise and/or exercises to strengthen muscles improve bone strength in those with osteoporosis. Aerobics, weight bearing, and resistance exercises all maintain or increase BMD in postmenopausal women. Fall prevention can help prevent osteoporosis complications. There is some evidence for hip protectors specifically among those who are in care homes.
Treatment for TRs is limited to tooth extraction because the lesion is progressive. Amputation of the tooth crown without root removal has also been advocated in cases demonstrated on a radiograph to be type 2 resorption without associated periodontal or endodontic disease because the roots are being replaced by bone. However, X-rays are recommended prior to this treatment to document root resorption and lack of the periodontal ligament.
Tooth restoration is not recommended because resorption of the tooth will continue underneath the restoration. Use of alendronate has been studied to prevent TRs and decrease progression of existing lesions.
Medications that are sometimes required include estrogen replacement therapy in postmenopausal women and bisphosphonates. Bisphosphonates may improve bone turnover.
Newer medications termed "calcimimetics" used in secondary hyperparathyroidism are now being used in primary hyperparathyroidism. Calcimimetics reduce the amount of parathyroid hormone released by the parathyroid glands. They are recommended in patients in whom surgery is inappropriate.
Once the process is recognized, it should be treated via the VIPs — vascular management, infection management and prevention, and pressure relief. Aggressively pursuing these three strategies will progress the healing trajectory of the wound. Pressure relief (off-loading) and immobilization with total contact casting (TCC) are critical to helping ward off further joint destruction.
TCC involves encasing the patient’s complete foot, including toes, and the lower leg in a specialist cast that redistributes weight and pressure in the lower leg and foot during everyday movements. This redistributes pressure from the foot into the leg, which is more able to bear weight, to protect the wound, letting it regenerate tissue and heal. TCC also keeps the ankle from rotating during walking, which prevents shearing and twisting forces that can further damage the wound. TCC aids maintenance of quality of life by helping patients to remain mobile.
There are two scenarios in which the use of TCC is appropriate for managing neuropathic arthropathy (Charcot foot), according to the American Orthopaedic Foot and Ankle Society. First, during the initial treatment, when the breakdown is occurring, and the foot is exhibiting edema and erythema; the patient should not bear weight on the foot, and TCC can be used to control and support the foot. Second, when the foot has become deformed and ulceration has occurred; TCC can be used to stabilize and support the foot, and to help move the wound toward healing.
Walking braces controlled by pneumatics are also used. Surgical correction of a joint is rarely successful in the long-term in these patients. However, off-loading alone does not translate to optimal outcomes without appropriate management of vascular disease and/or infection. Duration and aggressiveness of offloading (non-weight-bearing vs. weight-bearing, non-removable vs. removable device) should be guided by clinical assessment of healing of neuropathic arthropathy based on edema, erythema, and skin temperature changes. It can take 6–9 months for the edema and erythema of the affected joint to recede.
While bone resorption is commonly associated with many diseases or joint problems, the term "osteolysis" generally refers to a problem common to artificial joint replacements such as total hip replacements, total knee replacements and total shoulder replacements. Osteolysis can also be associated with the radiographic changes seen in those with bisphosphonate-related osteonecrosis of the jaw.
There are several biological mechanisms which may lead to osteolysis. In total hip replacement, the generally accepted explanation for osteolysis involves wear particles (worn off the contact surface of the artificial ball and socket joint). As the body attempts to clean up these wear particles (typically consisting of plastic or metal), it triggers an autoimmune reaction which causes resorption of living bone tissue. Osteolysis has been reported to occur as early as 12 months after implantation and is usually progressive. This may require a revision surgery (replacement of the prosthesis).
Although osteolysis itself is clinically asymptomatic, it can lead to implant loosening or bone breakage, which in turn causes serious medical problems.
Even though more studies are necessary for an efficient evaluation of the role played by zinc in senile osteoporosis, doctors recommend a proper supplementation of dietary zinc.
Replacement estrogen has proved to be an efficient way to combat the loss of bone mass in women when such treatment is started in the menopausal stage of their lives. John R. Lee, a Harvard graduate who wrote a book on the subject, came to the conclusion that by adding supplementation with natural progesterone to an existing natural osteoporosis treatment program, bone density was increased every year by 3-5% until it stabilized at the bone density levels expected for a 35-year-old woman, this after studies in 100 women between 38 and 83 with an average of 62 years old.
Recovery from renal osteodystrophy has been observed following kidney transplantation. Renal osteodystrophy is a chronic condition with a conventional hemodialysis schedule. Nevertheless, it is important to consider that the broader concept of CKD-MBD, which includes renal osteodystrophy, is not only associated with bone disease and increased risk of fractures but also with cardiovascular calcification, poor quality of life and increased morbidity and mortality in CKD patients (the so-called bone-vascular axis). Actually, bone may now be considered a new endocrine organ at the heart of CKD-MBD.
The aim of treatment is to minimize pain and to restore as much normal function as possible. Most humerus fractures do not require surgical intervention. One-part and two-part proximal fractures can be treated with a collar and cuff sling, adequate pain medicine, and follow up therapy. Two-part proximal fractures may require open or closed reduction depending on neurovascular injury, rotator cuff injury, dislocation, likelihood of union, and function. For three- and four-part proximal fractures, standard practice is to have open reduction and internal fixation to realign the separate parts of the proximal humerus. A humeral hemiarthroplasty may be required in proximal cases in which the blood supply to the region is compromised. Fractures of the humerus shaft and distal part of the humerus are most often uncomplicated, closed fractures that require nothing more than pain medicine and wearing a cast or sling for a few weeks. In shaft and distal cases in which complications such as damage to the neurovascular bundle exist, then surgical repair is required.
There is no cure, although curative therapy with bone marrow transplantion is being investigated in clinical trials. It is believed the healthy marrow will provide the sufferer with cells from which osteoclasts will develop. If complications occur in children, patients can be treated with vitamin D. Gamma interferon has also been shown to be effective, and it can be associated to vitamin D. Erythropoetin has been used to treat any associated anemia. Corticosteroids may alleviate both the anemia and stimulate bone resorption. Fractures and osteomyelitis can be treated as usual. Treatment for osteopetrosis depends on the specific symptoms present and the severity in each person. Therefore, treatment options must be evaluated on an individual basis. Nutritional support is important to improve growth and it also enhances responsiveness to other treatment options. A calcium-deficient diet has been beneficial for some affected people.
Treatment is necessary for the infantile form:
- Vitamin D (calcitriol) appears to stimulate dormant osteoclasts, which stimulates bone resorption
- Gamma interferon can have long-term benefits. It improves white blood cell function (leading to fewer infections), decreases bone volume, and increases bone marrow volume.
- Erythropoietin can be used for anemia, and corticosteroids can be used for anemia and to stimulate bone resorption.
Bone marrow transplantation (BMT) improves some cases of severe, infantile osteopetrosis associated with bone marrow failure, and offers the best chance of longer-term survival for individuals with this type.
In pediatric (childhood) osteopetrosis, surgery is sometimes needed because of fractures. Adult osteopetrosis typically does not require treatment, but complications of the condition may require intervention. Surgery may be needed for aesthetic or functional reasons (such as multiple fractures, deformity, and loss of function), or for severe degenerative joint disease.
The long-term-outlook for people with osteopetrosis depends on the subtype and the severity of the condition in each person.The severe infantile forms of osteopetrosis are associated with shortened life expectancy, with most untreated children not surviving past their first decade. seems to have cured some infants with early-onset disease. However, the long-term prognosis after transplantation is unknown. For those with onset in childhood or adolescence, the effect of the condition depends on the specific symptoms (including how fragile the bones are and how much pain is present). Life expectancy in the adult-onset forms is normal.
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.