Bisphosphonate associated osteonecrosis of the jaw.

In 2003, the first reports describing osteonecrosis of the jaw (ONJ) in patients receiving bisphosphonates (BP) were published. These cases occurred in patients with cancer receiving high-dose intravenous BP; however, 5% of the cases were in patients with osteoporosis receiving low-dose bisphosphonate therapy. We present the results of a systematic review of the incidence, risk factors, diagnosis, prevention, and treatment of BP associated ONJ. We conducted a comprehensive literature search for relevant studies on BP associated ONJ in oncology and osteoporosis patients published before February 2008.All selected relevant articles were sorted by area of focus. Data for each area were abstracted by 2 independent reviewers. The results showed that the diagnosis is made clinically. Prospective data evaluating the incidence and etiologic factors are very limited. In oncology patients receiving high-dose intravenous BP, ONJ appears to be dependent on the dose and duration of therapy, with an estimated incidence of 1%-12% at 36 months of exposure. In osteoporosis patients, it is rare, with an estimated incidence < 1 case per 100,000 person-years of exposure. The incidence of ONJ in the general population is not known. Currently, there is insufficient evidence to confirm a causal link between low-dose BP use in the osteoporosis patient population and ONJ. We concluded BP associated ONJ is associated with high-dose BP therapy primarily in the oncology patient population. Prevention and treatment strategies are currently based on expert opinion and focus on maintaining good oral hygiene and conservative surgical intervention.

Canadian consensus practice guidelines for bisphosphonate associated osteonecrosis of the jaw.

OBJECTIVE: Following publication of the first reports of osteonecrosis of the jaw (ONJ) in patients receiving bisphosphonates in 2003, a call for national multidisciplinary guidelines based upon a systematic review of the current evidence was made by the Canadian Association of Oral and Maxillofacial Surgeons (CAOMS) in association with national and international societies concerned with ONJ. The purpose of the guidelines is to provide recommendations regarding diagnosis, identification of at-risk patients, and prevention and management strategies, based on current evidence and consensus. These guidelines were developed for medical and dental practitioners as well as for oral pathologists and related specialists. METHODS: The multidisciplinary task force established by the CAOMS reviewed all relevant areas of research relating to ONJ associated with bisphosphonate use and completed a systematic review of current literature. These evidence-based guidelines were developed utilizing a structured development methodology. A modified Delphi consensus process enabled consensus among the multidisciplinary task force members. These guidelines have since been reviewed by external experts and endorsed by national and international medical, dental, oral surgery, and oral pathology societies. RESULTS: RECOMMENDATIONS regarding diagnosis, prevention, and management of ONJ were made following analysis of all current data pertaining to this condition. ONJ has many etiologic factors including head and neck irradiation, trauma, periodontal disease, local malignancy, chemotherapy, and glucocorticoid therapy. High-dose intravenous bisphosphonates have been identified as a risk factor for ONJ in the oncology patient population. Low-dose bisphosphonate use in patients with osteoporosis or other metabolic bone disease has not been causally linked to the development of ONJ. Prevention, staging, and treatment recommendations are based upon collective expert opinion and current data, which has been limited to case reports, case series, surveys, retrospective studies, and 2 prospective observational studies. RECOMMENDATIONS: In all oncology patients, a thorough dental examination including radiographs should be completed prior to the initiation of intravenous bisphosphonate therapy. In this population, any invasive dental procedure is ideally completed prior to the initiation of high-dose bisphosphonate therapy. Non-urgent procedures are preferably delayed for 3 to 6 months following interruption of bisphosphonate therapy. Osteoporosis patients receiving oral or intravenous bisphosphonates do not require a dental examination prior to initiating therapy in the presence of appropriate dental care and good oral hygiene. Stopping smoking, limiting alcohol intake, and maintaining good oral hygiene should be emphasized for all patients receiving bisphosphonate therapy. Individuals with established ONJ are most appropriately managed with supportive care including pain control, treatment of secondary infection, removal of necrotic debris, and mobile sequestrate. Aggressive debridement is contraindicated. CONCLUSION: Our multidisciplinary guidelines, which provide a rational evidence-based approach to the diagnosis, prevention, and management of bisphosphonate-associated ONJ in Canada, are based on the best available published data and the opinion of national and international experts involved in the prevention and management of ONJ.

Information and computer technology in oral and maxillofacial surgery.

The focus of this article is to provide the oral and maxillofacial surgeon with an overview of some of the recent information and computer technologies available in the marketplace as they relate to diagnostic imaging, implantology, orthognathic surgery, and craniofacial surgery. In so doing, the author hopes to highlight the various advantages and disadvantages of each of these technologies, and thus provide the clinician with a wider range armamentarium with which to treat his or her patient successfully and predictably.

Effects of estrogen on chondrocyte proliferation and collagen synthesis in skeletally mature articular cartilage.

PURPOSE: Estrogen has been shown to have a modulating effect on cartilage thickness. This investigation was performed to determine the effects of estrogen supplementation on cartilage thickness, cellular proliferation, and type II and X collagen production in skeletally mature rat cartilage, both in an organ culture and cell culture system. MATERIALS AND METHODS: Mandibular condyles were harvested from 8-week-old female Sprague Dawley rats and placed into tissue culture plates containing culture media with or without 17beta-estradiol supplementation. Organ cultures were labeled with 5-bromo-2'-deoxyuridine on culture day 2 or 4 to determine the effects of estrogen supplementation on the cellular mitotic index. Histomorphometric analysis of the organ culture sections was used to determine the thickness (microm) of the various cartilage zones, as well as the total cartilage thickness following estrogen exposure. Type X collagen was immunohistochemically identified in the ECM of hypertrophic chondrocytes using a rabbit anti-rat collagen type X antibody raised against the NCl domain. The reaction was visualized with an avidin-biotin peroxidase detection system (Vector Laboratories, Burlingame, CA). In a separate experiment, articulating cartilage chondrocytes were harvested by collagenase digestion and cultured at 5 x 10(5) cells per 35 mm tissue culture plate. Second subculture chondrocytes were divided into 2 groups: controls and [10(-8) M] 17beta-estradiol (E(2)-10(-8) M) and grown to confluence. The cell cultures were used to establish growth curves for each group using cell counts at 2-day intervals. RESULTS: In the organ culture experiment, 17beta-estradiol-treated condyles had a significant decrease in total cartilage thickness after 4 days in culture (P < .05). Estrogen supplementation resulted in a significant reduction in the mitotic index as early as culture day 2 (P < .05). Type X collagen deposition into the extracellular matrix was visibly increased in the hypertrophic chondrocyte zone for the estrogen-supplemented group on experimental days 2 and 4 compared with the control group. In the cell culture system, 17beta-estradiol [10(-8) M] decreased chondrocyte proliferation during logarithmic growth (P < .05) and at confluence (P < .05). CONCLUSION: These data show that estrogen decreased cartilage thickness by inhibition of chondrocyte proliferation and increased chondrocyte maturation. These observed effects showed the potential role of estrogen in the modulation of skeletally mature cartilage.

The American Association of Oral and Maxillofacial Surgeons Age-Related Third Molar Study.

PURPOSE: The purpose of this investigation was to assess the frequency of complications of third molar surgery, both intraoperatively and postoperatively, specifically for patients 25 years of age or older. MATERIALS AND METHODS: This prospective study evaluated 3,760 patients, 25 years of age or older, who were to undergo third molar surgery by oral and maxillofacial surgeons practicing in the United States. The predictor variables were categorized as demographic (age, gender), American Society of Anesthesiologists classification, chronic conditions and medical risk factors, and preoperative description of third molars (present or absent, type of impaction, abnormalities or association with pathology). Outcome variables were intraoperative and postoperative complications, as well as quality of life issues (days of work missed or normal activity curtailed). Frequencies for data collected were tabulated. RESULTS: The sample was provided by 63 surgeons, and was composed of 3,760 patients with 9,845 third molars who were 25 years of age or older, of which 8,333 third molars were removed. Alveolar osteitis was the most frequently encountered postoperative problem (0.2% to 12.7%). Postoperative inferior alveolar nerve anesthesia/paresthesia occurred with a frequency of 1.1% to 1.7%, while lingual nerve anesthesia/paresthesia was calculated as 0.3%. All other complications also occurred with a frequency of less than 1%. CONCLUSION: The findings of this study indicate that third molar surgery in patients 25 years of age or older is associated with minimal morbidity, a low incidence of postoperative complications, and minimal impact on the patients quality of life.

Biomaterials for use in frontal sinus obliteration.

Although fractures of the frontal sinus are infrequent (2-15% of victims of facial trauma), because of their proximity to the brain and eyes, the consequences of their management may have a significant impact on the patient. For frontal sinus injuries that affect the nasofrontal ducts or posterior wall, obliteration is indicated. Although frontal sinus surgery has been documented since 1750, a consensus as to the best material for obliteration has not been achieved. The particular autogenous and alloplastic materials for use in frontal sinus obliteration will be the focus of this review, with particular attention paid to assessing their physical properties, advantages, disadvantages, and complications. While numerous new alloplastic materials show promise for frontal sinus obliteration, autogenous fat remains the most popular and most frequently used material with the longest history of use, and it is versatile and reliable.

Comparison of 2 temporomandibular joint total joint prosthesis systems.

PURPOSE: The study goal was to evaluate the comparative outcomes of patients treated with temporomandibular joint (TMJ) total joint prostheses, using either the Christensen prosthesis (TMJ Inc, Golden, CO) (CP) or the TMJ Concepts prosthesis (TMJ Concepts Inc, Camarillo, CA; formerly Techmedica Inc) (TP). PATIENTS AND METHODS: Forty-five consecutive patients treated with either CP or TP total joint prostheses were evaluated. The CP group consisted of 23 patients (40 prostheses; average patient age, 38.8 years). The TP group consisted of 22 patients (38 prostheses; average patient age, 38.5 years). The average number of previous operations for the CP group was 3.9, whereas it was 2.6 for the TP group. The CP and TP groups had an average follow-up of 20.8 and 33.0 months, respectively. Patients were evaluated for incisal opening and occlusal and skeletal stability. A visual analog scale was used for subjective assessment of TMJ pain (0 = no pain, 10 = worst pain), jaw function (0 = normal function, 10 = no function), and diet (0 = no limitations, 10 = liquids only). Statistical analysis was performed using an independent t test, and a value of P <.05 was considered significant. RESULTS: The average postsurgical incisal opening for the CP group was 30.1 mm (increase of 6.7 mm), and that for the TP group was 37.3 mm (increase of 9.9 mm), indicating significant increase of the TP group (P =.008). The average postsurgical pain level for the CP group was 6.0, a decrease of 1.8, and that for the TP group was 4.1, a decrease of 3.1, indicating significant improvement for the TP group (P =.042). Postsurgical average jaw function for CP was 5.5, an improvement of 1.2. The postsurgical TP average was 3.9, an improvement of 3.0, showing significant improvement for the TP group (P =.008). Average postsurgical diet rating for the CP group was 5.4, an improvement of 1.8. The TP group average was 3.9, an improvement of 2.0, indicating significant improved eating ability for the TP group (P =.021). Skeletal and occlusal stability were good in both groups. CONCLUSION: The TP group had statistically significant improved outcomes compared with the CP group relative to postsurgical incisal opening, pain, jaw function, and diet. Both groups showed good skeletal and occlusal stability.