Comment on the American Association of Oral and Maxillofacial Surgeons statement on bisphosphonates

Pharmacologic augmentation of implant fixation in osteopenic bone

Osteoporosis presents a challenge for successful implant fixation due to an impaired healing response. Preclinical studies have consistently reported reduced osseointegration capability in trabecular bone. Although clinical studies of implant success in dentistry have not found a negative effect due to osteoporosis, low bone mass is a significant risk factor for implant migration in orthopedics. Pharmacologic treatment options that limit bone resorption or upregulate formation have been studied preclinically. While, both treatment options improve implant fixation, direct comparisons to-date have found anti-catabolic more effective than anabolic treatments for establishing implant fixation, but combination approaches are better than either treatment alone. Clinically, anti-catabolic treatments, particularly bisphosphonates have been shown to increase the longevity of implants, while limited clinical evidence on the effects of anabolic treatment exists. Preclinical experiments are needed to determine the effects of osteoporosis and subsequent treatment on the long-term maintenance of fixation and recovery after bone loss.

Bisphosphonate-related osteonecrosis of the jaw in non-malignant bone disease

Bisphosphonates such as alendronate, risedronate and zoledronate have revolutionised the treatment for osteoporosis and Paget's disease. These drugs reduce fracture risk and probably mortality in patients with osteoporosis. However, they have a long in vivo half-life following cessation and may be associated with delayed dental healing and even the devastating complication of osteonecrosis of the jaw (ONJ). Extensive media attention highlighting this issue has caused much concern among patients and healthcare professionals. This paper seeks to provide treating clinicians with a balanced multi-disciplinary review of the available evidence pertaining to this issue and practical advice regarding prevention and management of ONJ.

Practical considerations for treatment of patients taking bisphosphonate medications: an update

Osteonecrosis of the jaw--bisphosphonate-related (ONJ-BR) is an established clinical entity associated with both oral and intravenous (IV) bisphosphonate therapy. An update for the general practitioner on the indications for bisphosphonate therapy and both risk assessment and prevalence of ONJ-BR is provided. Management philosophy within a local unit is illustrated through four brief case studies. It is not uncommon to encounter patients on bisphosphonate therapy in the dental practice environment; the vast majority of these will be on oral bisphosphonates as part of their management for osteoporosis. The risk of developing ONJ-BR is rare in these patients compared with those receiving treatment for skeletal complications associated with cancer, many of whom will be managed with IV bisphosphonates. Although rare, it is important to recognize the potential risk of ONJ-BR. Whilst most patients on oral bisphosphonates can be managed no differently from other patients, it should be appreciated that the relative risk of long-term cumulative exposure, comorbidity and other factors are still to be determined. Surgical intervention and extractions can place the patient at risk of ONJ-BR and vigilance is necessary to ensure that healing progresses satisfactorily. Early referral to the local hospital should be sought if there is cause for concern.

CLINICAL RELEVANCE

Although the risk of ONJ-BR is low in non-oncological indications, it is important to be aware that it exists and to know how the risk may be minimized.

[Optimizing orthodontic treatment in patients taking bisphosphonates]

Bisphosphonates have unique pharmacological characteristics unlike those of any other drug group. Millions of adults take oral bisphosphonates for long-term treatment of osteoporosis and osteopenia; some of these people will most likely also seek orthodontic treatment. Adverse dental effects from bisphosphonates have been reported, including decreased tooth movement, impaired bone healing, and osteonecrosis in the mandible and the maxilla. Osteonecrosis has been rarely observed after bisphosphonate use for osteoporosis. However, adverse drug effects might occur more frequently in orthodontic patients, and they would probably be noted before the end-stage pathology of osteonecrosis. Adverse effects during orthodontic treatment, including decreased tooth movement, could last for years after the drug therapy is stopped. Successful orthodontic treatment requires optimal bone healing to prevent excessive tooth mobility. Bisphosphonates appear to have two bone elimination rates - a fast elimination of weeks from the bone surface and a slow elimination of years after incorporation into the bone structure. This article presents methods to clinically and radiographically monitor orthodontic patients who are taking oral bisphosphonates. Efforts to minimize adverse effects and optimize orthodontic procedures with physician-approved drug holidays are discussed. The orthodontic treatment results of three patients who received bisphosphonate therapy are reported.

Temporomandibular joint: disorders, treatments, and biomechanics

Temporomandibular joint (TMJ) is a complex, sensitive, and highly mobile joint. Millions of people suffer from temporomandibular disorders (TMD) in USA alone. The TMD treatment options need to be looked at more fully to assess possible improvement of the available options and introduction of novel techniques. As reconstruction with either partial or total joint prosthesis is the potential treatment option in certain TMD conditions, it is essential to study outcomes of the FDA approved TMJ implants in a controlled comparative manner. Evaluating the kinetics and kinematics of the TMJ enables the understanding of structure and function of normal and diseased TMJ to predict changes due to alterations, and to propose more efficient methods of treatment. Although many researchers have conducted biomechanical analysis of the TMJ, many of the methods have certain limitations. Therefore, a more comprehensive analysis is necessary for better understanding of different movements and resulting forces and stresses in the joint components. This article provides the results of a state-of-the-art investigation of the TMJ anatomy, TMD, treatment options, a review of the FDA approved TMJ prosthetic devices, and the TMJ biomechanics.

Osteonecrosis of the jaw complicating bisphosphonate treatment for bone disease in multiple myeloma: an overview with recommendations for prevention and treatment

Osteonecrosis of the Jaw (ONJ) is a recently recognised and potentially highly morbid complication of bisphosphonate therapy in the setting of metastatic malignancy, including myeloma. Members of the Medical and Scientific Advisory Group of the Myeloma Foundation of Australia formulated guidelines for the management of bisphosphonates around the issue of ONJ, based on the best available evidence in June 2008. Prior to commencement of therapy, patients should have an oral health assessment and be educated about the risks of ONJ. Dental assessment should occur 6 monthly during therapy. If tooth extraction is required, sufficient time should be allowed for complete healing to occur prior to commencement of bisphosphonate. As the risk of ONJ increases with duration of bisphosphonate therapy, we recommend annual assessment of dose with modification to 3 monthly i.v. therapy or to oral therapy with clodronate for those with all but the highest risk of skeletal-related event. Established ONJ should be managed conservatively; a bisphosphonate "drug holiday" is usually indicated and invasive surgery should generally be avoided. These recommendations will assist with clinical decision making for myeloma patients who are at risk of bisphosphonate-associated ONJ.