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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.
Osteoporotic bone marrow defect is a condition which may be found in the body of the mandible. It is usually painless and found during routine radiographs. It appears as a poorly defined radiolucency (dark area) where there was a previous history of an extraction of a tooth. It may resemble a metastatic disease.
It is a localized increase of hematopoietic bone marrow that creates a radiolucent radiographic defect. They occur more commonly in women in the midyears and show a predilection for the molar region of the mandible. They are especially common in extraction sites. Scattered trabeculae may extend short distances into the defect or, in some instances, through it, giving the defect a fairly characteristic appearance. Naturally there are no clinical symptoms.
Treatment in fibrous dysplasia is mainly palliative, and is focused on managing fractures and preventing deformity. There are no medications capable of altering the disease course. Intravenous bisphosphonates may be helpful for treatment of bone pain, but there is no clear evidence that they strengthen bone lesions or prevent fractures. Surgical techniques that are effective in other disorders, such as bone grafting, curettage, and plates and screws, are frequently ineffective in fibrous dysplasia and should be avoided. Intramedullary rods are generally preferred for management of fractures and deformity in the lower extremities. Progressive scoliosis can generally be managed with standard instrumentation and fusion techniques. Surgical management in the craniofacial skeleton is complicated by frequent post-operative FD regrowth, and should focus on correction of functional deformities. Prophylactic optic nerve decompression increases the risk of vision loss and is contraindicated.
Managing endocrinopathies is a critical component of management in FD. All patients with fibrous dysplasia should be evaluated and treated for endocrine diseases associated with McCune–Albright syndrome. In particular untreated growth hormone excess may worsen craniofacial fibrous dysplasia and increase the risk of blindness. Untreated hypophosphatemia increases bone pain and risk of fractures.
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.
Fibrous dysplasia is a disorder where normal bone and marrow is replaced with fibrous tissue, resulting in formation of bone that is weak and prone to expansion. As a result, most complications result from fracture, deformity, functional impairment, and pain. Disease occurs along a broad clinical spectrum ranging from asymptomatic, incidental lesions to severe disabling disease. Disease can affect one bone (monostotic) or multiple (polyostotic), and may occur in isolation or in combination with cafe-au-lait skin macules and hyperfunctioning endocrinopathies, termed McCune-Albright syndrome. More rarely, fibrous dysplasia may be associated with intramuscular myxomas, termed Mazabraud's syndrome. Fibrous dysplasia is very rare, and there is no known cure. Fibrous dysplasia is not a form of cancer.
This defect may easily be mistaken for a cyst or tumor. Biopsy is required to rule these out.
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.
A systematic review reported that there is some evidence that rinsing with chlorhexidine (0.12% or 0.2%) or placing chlorhexidine gel (0.2%) in the sockets of extracted teeth reduces the frequency of dry socket. Another systematic review concluded that there is evidence that prophylactic antibiotics reduce the risk of dry socket (and infection and pain) following third molar extractions of wisdom teeth, however their use is associated with an increase in mild and transient adverse effects. The authors questioned whether treating 12 patients with antibiotics to prevent one infection would do more harm overall than good, in view of the potential side effects and also of antibiotic resistance. Nevertheless, there is evidence that in individuals who are at clear risk may benefit from antibiotics. There is also evidence that antifibrinolytic agents applied to the socket after the extraction may reduce the risk of dry socket.
Some dentists and oral surgeons routinely debride the bony walls of the socket to encourage hemorrhage (bleeding) in the belief that this reduces the incidence of dry socket, but there is no evidence to support this practice. It has been suggested that dental extractions in females taking oral contraceptives be scheduled on days without estrogen supplementation (typically days 23–28 of the menstrual cycle). It has also been suggested that teeth to be extracted be scaled prior to the procedure.
Prevention of alveolar osteitis can be exacted by following post-operative instructions, including:
1. Taking any recommended medications
2. Avoiding intake of hot fluids for one to two days. Hot fluids raise the local blood flow and thus interfere with organization of the clot. Therefore, cold fluids and foods are encouraged, which facilitate clot formation and prevent its disintegration.
3. Avoiding smoking. It reduces the blood supply, leading to tissue ischemia, reduced tissue perfusion and eventually higher incidence of painful socket.
4. Avoiding drinking through a straw or spitting forcefully as this creates a negative pressure within the oral cavity leading to an increased chance of blood clot instability.
Most of the etiologic considerations regarding senile osteoporosis are not very clear for physicians yet. But based on the current evidence attached to clinical experimentation, it has been determined that the pathogenesis of the disease is clearly related to a deficiency of zinc. Such deficiency is known to lead to an increment of endogenous heparin, which is most likely caused by mast cell degranulation, and an increase in the bone resorption (calcium discharge in the bones) reaction of prostaglandin E2, which constrain the formation of more bone mass, making bones more fragile. These co-factors are shown to play an important role in the pathogenetic process attached to senile osteoporosis as they enhance the action of the parathyroid hormone.
The intake of calcium in elder people is quite low, and this problem is worsened by a reduced capability to ingest it. This, attached to a decrease in the absorption of vitamin D concerning metabolism, are also factors that contributes to a diagnosis of osteoporosis type II.
By definition, a nonunion will not heal if left alone. Therefore the patient's symptoms will not be improved and the function of the limb will remain impaired. It will be painful to bear weight on it and it may be deformed or unstable. The prognosis of nonunion if treated depends on many factors including the age and general health of the patient, the time since the original injury, the number of previous surgeries, smoking history, the patient's ability to cooperate with the treatment. In the region of 80% of nonunions heal after the first operation. The success rate with subsequent surgeries is less.
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.
Bone stimulation may be with either electromagnetic or ultrasound waves. Ultrasound stimulation has tentative evidence of supporting better healing in long bones that have not healed after three months. Evidence; from a Cochrane review however, does not show that ultrasound decreases rates of nonunion. Another review has, however, suggested it as an alternative to surgery.
The primary treatment for CAMT is bone marrow transplantation.
Bone Marrow/Stem Cell Transplant is the only thing that ultimately cures this genetic disease. Frequent platelet transfusions are required to ensure that platelet levels do not fall to dangerous levels, although this is not always the case. It is known for patients to continue to create very small numbers of platelets over time.
Treatment consists mainly of high dose antibiotics for active infections and prophylactic antibiotics for prevention of future infections. GM-CSF therapy or bone marrow transplant might be considered for severe cases. Prognosis is difficult to predict, but patients receiving treatment are generally able to survive to adulthood.
Certain medications have been associated with an increase in osteoporosis risk; only glucocorticosteroids and anticonvulsants are classically associated, but evidence is emerging with regard to other drugs.
- Steroid-induced osteoporosis (SIOP) arises due to use of glucocorticoids – analogous to Cushing's syndrome and involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug prednisone is a main candidate after prolonged intake. Some professional guidelines recommend prophylaxis in patients who take the equivalent of more than 30 mg hydrocortisone (7.5 mg of prednisolone), especially when this is in excess of three months. Alternate day use may not prevent this complication.
- Barbiturates, phenytoin and some other enzyme-inducing antiepileptics – these probably accelerate the metabolism of vitamin D.
- L-Thyroxine over-replacement may contribute to osteoporosis, in a similar fashion as thyrotoxicosis does. This can be relevant in subclinical hypothyroidism.
- Several drugs induce hypogonadism, for example aromatase inhibitors used in breast cancer, methotrexate and other antimetabolite drugs, depot progesterone and gonadotropin-releasing hormone agonists.
- Anticoagulants – long-term use of heparin is associated with a decrease in bone density, and warfarin (and related coumarins) have been linked with an increased risk in osteoporotic fracture in long-term use.
- Proton pump inhibitors – these drugs inhibit the production of stomach acid; this is thought to interfere with calcium absorption. Chronic phosphate binding may also occur with aluminium-containing antacids.
- Thiazolidinediones (used for diabetes) – rosiglitazone and possibly pioglitazone, inhibitors of PPARγ, have been linked with an increased risk of osteoporosis and fracture.
- Chronic lithium therapy has been associated with osteoporosis.
In terms of treatment for individuals with Nezelof syndrome, which was first characterized in 1964, includes the following(how effective bone marrow transplant is uncertain) :
- Antimicrobial therapy
- IV immunoglobulin
- Bone marrow transplantation
- Thymus transplantation
- Thymus factors
The treatment of osteopenia is controversial. Currently, candidates for therapy include those at the highest risk of osteoporotic bone fracture based on bone mineral density and clinical risk factors. As of 2008, recommendations from the US National Osteoporosis Foundation (NOF) are based on risk assessments from the World Health Organization (WHO) Fracture Risk Assessment Tool (FRAX). According to these recommendations, consideration of therapy should be made for postmenopausal women, and men older than 50 years of age, if any one of the following is present:
1. Prior hip or vertebral fracture
2. T-score of −2.5 at the femoral neck or spine, excluding secondary causes
3. T-score between −1.0 and −2.5 at the femoral neck or spine "and" a 10-year probability of hip fracture ≥3% "or" a 10-year probability of major osteoporotic fracture ≥20%
4. Clinicians' judgment in combination with patient preferences indicate treatment for people with 10-year fracture probabilities above or below these levels.
When medical therapy is pursued, treatment includes medications with a range of actions. Commonly used drugs are bisphosphonates including alendronate, risedronate, and ibandronate; selective estrogen receptor modulators (SERMs) such as raloxifene; estrogen; calcitonin; and teriparatide.
Studies have shown that the actual benefits of these drugs may be marginal. Approximately 270 women with osteopenia might need to be treated with drugs for three years so that one of them could avoid a single vertebral fracture.
Strontium ranelate has been approved in 27 European countries, having been found to build bone both by slowing the work of osteoclasts and by stimulating osteoblasts. On January 10, 2014, the European Pharmacovigilance Risk Assessment Committee recommended that strontium ranelate, marketed as Protelos or Protos by Servier, should be treated with caution when used to treat osteoporosis, as randomised trials have shown an increased risk of non-fatal myocardial infarction in patients with ischemic heart disease or uncontrolled hypertension patients. There is no increased risk of non-fatal myocardial infarction in healthy patients.
Other (natural) forms of available strontium include strontium lactate, strontium gluconate, strontium carbonate, and strontium citrate. Food sources include spices (especially basil), seafood, whole grains, root and leafy vegetables, and legumes. Strontium should not be taken with calcium supplements, to improve absorption.
Gene therapy is a relatively new concept in the field of SCID. This therapy is currently undergoing clinical trial and has cured a small number of children suffering from X-linked SCID and recessive allele SCID. Gene therapy aims to correct the underlying genetic abnormality in SCID. In the case of RD, the genetic abnormality would be AK2 malfunction. Stem cells are taken from an affected child's blood or bone marrow. Then in laboratory conditions the stem cells are manipulated and corrected with gene technology. They are then injected back into the patient. Similarly, in bone transplant, stem cells are able to find their way back through tracking mechanisms.
Osteopenia is a condition in which bone mineral density is lower than normal. It is considered by many doctors to be a precursor to osteoporosis. However, not every person diagnosed with osteopenia will develop osteoporosis. More specifically, osteopenia is defined as a bone mineral density T-score between −1.0 and −2.5.
Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare inherited disorder.
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.
The survival range is estimated to be 3 days to 17 weeks without treatment. Patients die due to bacterial or viral infections. Aggressive treatment with antibiotics is required and bone marrow transplant is common. Patients undergoing bone marrow transplant, specifically from a matched sibling, have a higher 5 year survival rate than those receiving a transplant from other donors.
Radiotherapy is the main choice of treatment for both SPB and extramedullary plasmacytoma, and local control rates of >80% can be achieved. This form of treatment can be used with curative intent because plasmacytoma is a radiosensitive tumor. Surgery is an option for extramedullary plasmacytoma, but for cosmetic reasons it is generally used when the lesion is not present within the head and neck region.
Treatment of this disorder involves treatment of the underlying cancer.
Treatment is supportive.
- The aplastic anemia and immunodeficiency can be treated by bone marrow transplantation.
- Supportive treatment for gastrointestinal complications and infections.
- Genetic counselling.