Case Report: Development of medication-related osteonecrosis of the jaw in a patient on long-term infliximab therapy.

Medication-Related Osteonecrosis of the Jaw (MRONJ) is a challenging and evolving aspect of Oral and Maxillofacial Surgery. In recent years, several medications apart from those traditionally associated with MRONJ such as bisphosphates (BPs) and Denosumab (DMB) have been implicated in bony necrosis of the jaw. This aim of this report is to demonstrate a significant case of bone necrosis following dental extractions on a patient being treated with infliximab therapy for Crohn's disease. Several cases in literature have reported MRONJ associated with infliximab but very few patients have developed as significant a form of the disease as seen in this report. Previous investigators have proposed pathophysiological pathways via which TNF-α inhibitors such as infliximab have a causative mechanism for MRONJ. When osteoclastic activity is restricted via these pathways, bone healing is impaired and MRONJ can occur. However, it remains a diagnostic challenge to differentiate between antiresorptive MRONJ and chronic osteomyelitis with bone necrosis in patients with acquired immunodeficiency. This case aims to illustrate why the antiresorptive effects of TNF-α inhibitors need to be considered as a possible primary driver of bone necrosis in such patients.

Mandibular tori as bone grafts: an alternative treatment for periodontal osseous defects - clinical, radiographic and histologic morphology evaluation.

OBJECTIVES: The present study was designed to evaluate the clinical, radiographic and histochemical significance of using the mandibular tori as autogenous bone graft for treatment of intraosseous defects in patients with chronic periodontitis. MATERIALS AND METHODS: Twenty-eight sites from 14 patients with chronic periodontitis were included in this study. Each patient was treated with split mouth design; one site received torus mandibularis bone graft and the other site received a full-thickness fap alone. Histopathologic assessment was evaluated on removal of torus mandibularis to evaluate its histologic structure and by the end of the study 9 month later. Clinical and radiographic parameters were re-evaluated at 3 months interval for 1 year. RESULTS: The results of the present study revealed significant gain in the clinical attachment level (CAL) (88.4%, 4.53 ± 0.06 mm) for torus mandibularis sites compared to (39.7%, 2.01 ± 0.04 mm) for full-thickness fap. Moreover, there was a reduction in the probing pocket depth (PPD) of (75.4%, 5.75 ± 0.12 mm) for torus mandibularis sites and (49.6%, 3.73 ± 0.14 mm) for sites treated with a full-thickness fap only; CAL and PPD differences were significant at p-value ≤0.01. Concomitantly, significant radiographic increase in the bone height and density were recorded in the test group. CONCLUSION: The use of mandibular tori as autogenous bone graft could provide benefits as a periodontal therapeutic modality and enhance regenerative potential of periodontal intraosseous defects.

Does the presence or position of lower third molars alter the risk of mandibular angle or condylar fractures?

PURPOSE: The purpose of this study was to determine whether a relation exists between the presence of mandibular third molars (M3s) and mandibular angle and condylar fractures and whether the risk of these fractures varies with M3 position. MATERIALS AND METHODS: A retrospective cohort study was conducted in patients with mandibular fractures presenting to the oral and maxillofacial surgery service from April 2007 to March 2012. Data sources were patients' hospital charts and panoramic radiographs. Predictor variables were the presence and position of M3s. M3 position was based on the Pell and Gregory classification and angulation was determined by measuring the angle between the long axis of the M3 and the mandibular occlusal plane. Outcome variables were the presence of angle and condylar fractures. Other study variables included age, gender, and fracture etiology. Data were analyzed using the χ(2) test and Student t test. RESULTS: The study sample consisted of 446 patients with 731 mandibular fractures. Results showed that the risk of mandibular angle fracture was significantly higher in patients and mandible sides with impacted M3s (P < .001), whereas the risk of condylar fracture was significantly higher in patients and mandible sides lacking impacted M3s (P < .001). A relation between the position of M3s to angle or condylar fractures could not be found (P > .05). CONCLUSION: The presence of impacted M3s increased the risk of angle fracture and simultaneously decreased the risk of condylar fracture. However, no relation appeared to exist between M3 position and fracture pattern.

Effect of bilateral mandibular osteodistration on the condylar cartilage: an experimental study on rabbits.

UNLABELLED: Although various aspects of bone formation during distraction osteogenesis have been studied extensively, there are only limited experimental data concerning the influence of hyper-physiologic mandibular distraction rate on structural alterations in the temporomandibular joint (TMJ) condylar cartilage. The purpose of this study was to evaluate the effect of bilateral distraction osteogenesis of the mandibular body, at a hyper-physiologic rate and length, on the integrity of the condylar cartilage in rabbits. MATERIALS AND METHODS: Eighteen healthy adult male rabbits weighing 2 to 3 kg were assigned to 1 of 2 groups: the control group (n = 2 rabbits, 4 joints) or the study group (n = 16 rabbits, 32 joints) four rabbits (8 joints) in each subgroup according to the post-distraction period (1,2,3 or 4 weeks). In the control group, rabbits received sham surgery (Osteotomy without distraction) and then left to live for 4 weeks under the same condition of the study group then euthanized using intravenous overdose of pentobarbital sodium. In the study group, an extra oral custom-made distracter was employed to achieve bilateral mandibular hyper physiologic distraction (1.5 mm twice daily for 5 days) distraction. All animals were evaluated clinically and histomorphometrically and results analyzed by MINITABE 13.1 statistical package using ANOVA test. RESULTS: Animals underwent distraction showed obvious changes in condylar surface contour related to length of the follow up period, compared to the control; these changes seemed to be partly reversible. The most pronounced observation was the irregularities and resorption in the anterior part of the condylar cartilage and the subcondylar bone. Moreover, at the first two weeks, the area of resorption was invaded by large number of osteoclasts and chronic inflammatory cells which declined later in the 3rd and 4th weeks and replaced with osteoblastic activities. CONCLUSION: These experimental data showed that distraction rate of 3 mm per day may lead to degenerative or even early arthritic changes in the TMJ condylar cartilage in the 1st and 2nd post-distraction weeks. However, all condyles showed adaptive and remodeling sings in the following 3rd and 4th weeks.

Cyanoacrylate glue versus suture in peripheral nerve reanastomosis.

OBJECTIVE: To assess the effectiveness of n-butyl-2-cyanoacrylate glue compared with microsuturing technique in peripheral nerve reanastomosis in rats. STUDY DESIGN: Fourteen young adult white rats were used. Bilateral sciatic neurotomies were performed in 12 of them and then reanastomosed with 3 epineural microsutures in the right side (study group G1) and with n-butyl-2-cyanoacrylate glue in the left side (study group G2). On the remaining 2 rats (control group G3), sham surgery was done on both sides. Biopsies were harvested 12 weeks after surgery and examined under light microscope using Osmic acid stains. The number of nerve fibers was counted in the distal and proximal nerve segments, and the results were analyzed and compared in all groups. RESULTS: Adequate regeneration with no anastomotic ruptures was seen 12 weeks after surgery in G1 and G2. The histomorphometric assessment showed no statistically significant difference (P = .960) in the neurotization index of G1 (89.01%) compared with G2 (88.97%). There was a significant (P = .001) reduction in the mean number of axon counts distal to the repair in G1 (271.3) and G2 (272.8) compared with that of the proximal segments of each study group (304.6 and 303, respectively, as well as to that of G3 (348.5). CONCLUSION: Both n-butyl-2-cyanoacrylate adhesive and 3-microsuture techniques showed comparable neurotization indices and were equally adequate to stabilize the nerve during regeneration period.