Osteonecrosis of the jaw (ONJ) can be associated with nitrogen-containing bisphosphonates (NBPs) therapy. Various mechanisms of NBP-associated ONJ have been proposed and there is currently no consensus of the underlying pathogenesis. The detailed medical and dental histories of 30 ONJ patients treated with NBPs for malignant diseases (24) or osteoporosis (6) were analyzed. The necrotic bone was resected and analyzed histologically after demineralization. In 10 patients the perinecrotic bone was also resected and processed without demineralization. Alveolar bone samples from 5 healthy patients were used as controls. In 14 ONJ patients, serial technetium-99m-methylene diphosphonate scintigraphic scans were also available and confronted to the other data. Strong radionuclide uptake was detected in some patients several months before clinical diagnosis of ONJ. The medullary spaces of the necrotic bone were filled with bacterial aggregates. In the perinecrotic bone, the bacteria-free bone marrow characteristically showed an inflammatory reaction. The number of medullary inflammatory cells taken as an index of inflammation allowed us to discriminate two inflammation grades in the ONJ samples. Low-grade inflammation, characterized by marrow fibrosis and low inflammatory cells infiltration, increased numbers of TRAP + monoand multineacleated cells was seen in patients with bone exposure b 2 cm 2 . High-grade inflammation, associated with larger lesions, showed amounts of tartrate-resistant acid phosphatase + /calcitonin receptor − mono-and multinucleated cells, osteocyte apoptosis, hypervascularization and high inflammatory cell infiltration. The clinical extent of ONJ was statistically linked to the numbers of inflammatory cell. Taken together these data suggest that bone necrosis precedes clinical onset and is an inflammation-associated process. We hypothesize that from an initial focus, bone damage spreads centrifugally, both deeper into the jaw and towards the mucosa before the oral bone exposure and the clinical diagnosis of ONJ.

Atrophic posterior maxillae can be predictably rehabilitated using OSFE with a simultaneous implant placement. The new bone formed around implants after 1 year was stable after 5 years, irrespective of the presence or the absence of graft. Grafting was unnecessary to achieve an average bone augmentation of 3.8 mm, but more bone was gained with grafting.

Background:Little is known about the long-term outcome of implants placed in the atrophic maxilla using osteotome sinus floor elevation (OSFE) without grafting.

The Laryngoscope V C 2013 The American Laryngological, Rhinological and Otological Society, Inc. Potential Adverse Events of Endosseous Dental Implants Penetrating the Maxillary Sinus: Long-Term Clinical EvaluationSemaan Abi Najm, DDS, MS; Didier Malis, MD, DMD; Marc El Hage, DDS, MS; Sonia Rahban, DDS;Jean-Pierre Carrel, MD, DMD; Jean-Pierre Bernard, MD Objectives/Hypothesis: The aim of this study was to evaluate the nature and incidence of long-term maxillary sinus adverse events related to endosseous implant placement with protrusion into the maxillary sinus.Study Design: Retrospective cohort study. Methods: All patients who underwent placement of endosseous dental implants with clinical evidence of implant penetration into the maxillary sinus with membrane perforation were included in this study. Only patients with a minimum follow-up of 5 years after implant placement were included in this study. Maxillary sinus assessment was both clinical and radiological.Results: Eighty-three implants with sinus membrane perforation in 70 patients met the study's inclusion criteria. Mean age was 65.96 years 6 14.23. Twelve patients had more than one implant penetrating the maxillary sinus, and seven of them had bilateral sinus perforation. Estimated implant penetration was 3 mm in all cases. The average clinical and radiological follow-up was 9.98 years 6 3.74 (range 60-243 months). At the follow-up appointments, there were no clinical or radiological signs of sinusitis in any patient.Conclusion: This long-term study, spreading over a period of up to 20 years, indicates that no sinus complication was observed following implant penetration into the maxillary sinus. Furthermore, absence of occurrence of such complications is related to the maintenance of successful osseointegration. A contrario, and in the presence of an acute or chronic maxillary sinusitis, the differential diagnosis must always consider other potential odontogenic and nonodontogenic etiologies.

These results deserve further investigations involving a larger cohort. However, they strongly suggest that the guidelines of management of patients with ONJ related to NBPs have to be reconsidered.