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Purpose: To assess the prevalence of radiographic signs of maxillary sinus pathology in patients undergoing dental implant treatment and to compare the efficacy of panoramic radiography, computed tomography (CT), and three-dimensional (3D) CT with Implametric software in the diagnosis of sinus pathology., Materials and Methods: Thirty patients were selected at random from those being treatment-planned to receive implant-supported restorations in the maxilla and who had a panoramic radiograph, a conventional CT scan in acetate, and a 3D CT scan in digital format. The radiographic maxillary sinus findings were categorized as: (1) no sign of pathology, (2) mucosal thickening, (3) mucous cyst, or (4) occupation of the entire sinus., Results: Seventeen women and 13 men were included, with a mean age of 50.9 years. There was a 38.3% prevalence of radiographic abnormalities (23.3% mucosal thickenings, 10% mucous cysts, and 5% occupation of the entire sinus). Of the 23 sinuses that displayed radiographic signs of pathology, only 1 (4.3%) was correctly diagnosed by the panoramic radiograph., Conclusions: The most common radiographic maxillary sinus finding was mucosal thickening, followed by mucous cysts and occupation of the whole sinus. Conventional CT can be considered a reliable method for the diagnosis of maxillary sinus pathology.

Purpose: To determine the prevalence, location, and size of maxillary sinus septa, and to compare the results of panoramic radiographs and computed tomography (CT) scans., Materials and Methods: This study included 30 patients, 17 women and 13 men, with a mean age of 50.9 years (range, 28-73 years), undergoing treatment planning for implant-supported restorations in the maxilla. Three observers analyzed the panoramic radiographs, the conventional CT scans in acetate, and the Implametric 3-dimensional CT (3Dent, Valencia, Spain). The maxillary sinus septa of each patient and the type of septa, as well as its location and size, were recorded., Results: In 60 maxillary sinuses, panoramic radiographs showed 32 septa (53.3%); CT in acetate showed 42 septa (70%); and Implametric 3-dimensional CT showed 40 septa (66.7%). Most septa (60%) were located in the middle region of the maxillary sinus, 22.5% in the posterior region, and 17.5% in the anterior region. The mean height of the septa was 4.78 ± 1.76 mm. Panoramic radiographs led to an erroneous diagnosis in 46.5% of the cases., Conclusions: Maxillary sinus septa are a frequent anatomic variation. They can be found in any of the maxillary sinus regions independently of patient edentulism. The panoramic radiograph can lead to false-positive and false-negative findings in the visualization of septa in almost half of cases. Therefore, whenever a maxillary sinus lift is planned, a thorough study of the affected sinus should be made using CT., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

This review analyzes articles published on the presence of septa in maxillary sinuses. An automated search was conducted on PubMed using different key words. This search resulted in 11 papers in which the presence of antral septa was assessed. These septa are barriers of cortical bone that arise from the floor or from the walls of the sinus and may even divide the sinus into two or more cavities. They may originate during maxillary development and tooth growth, in which case they are known as primary septa; or they may be acquired structures resulting from the pneumatization of maxillary sinus after tooth loss, in which case they are called secondary septa. Several methods have been used in their study, direct observation on dried skulls or during sinus lift procedures; and radiographic observation using panoramic radiographs or computed tomographs. Between 13 and 35.3% of maxillary sinuses have septa. They can be located in any region of the maxillary sinus and their size can vary between 2.5 and 12.7 mm in mean length. Some authors have reported a higher prevalence of septa in atrophic edentulous areas than in non-atrophic ones. If a sinus lift is conducted in the presence of maxillary sinus septa, it may be necessary to modify the design of the lateral window in order to avoid fracturing the septa.

The aim of this paper was to review the procedures adopted when a perforation of the sinus membrane takes place during a direct sinus lift for filling with bone graft; and the survival of implants in those cases in which perforation of the sinus membrane occurred. A bibliographical search in PUBMED was carried out of articles published from 1997 to 2008, with the key words "sinus perforation" and "membrane perforation". All articles specifying the two following criteria were included: (a) procedure in the case of perforation of the sinus membrane during direct sinus lift; and (b) the number and survival rate of implants placed in direct sinus lift with perforated and non perforated membrane. Six articles fulfilled the inclusion criteria. In all the articles the sinus lift was continued when a perforation of the sinus membrane took place. In maxillary sinus lift procedures with perforation of the membrane a 88.6% implant survival rate was obtained, and in maxillary sinus lifts with intact membrane the survival rate rose to 98%. In case of small perforation of the sinus membrane, it is possible to continue with the procedure; there is no consensus on the procedure when a perforated membrane is to be repaired, but the method of choice according to the majority of authors is to use a reservable membrane. In the case of large perforation, there is no consensus either, although the majority of authors choose to abandon the procedure. The survival of the implants diminishes when they are placed in sinus lifts with perforated membrane.

Objectives The aim of this study was to perform an ultrastructural study of the bone-to-biomaterial interface and biomaterial mineral degradation in retrieved bone biopsies following maxillary sinus augmentation using bovine xenografts (Endobon®) in 15 clinical cases. Materials and methods Nine months after sinus lifting, bone cores were harvested from the maxillary sinus. The specimens were processed for observation under a scanning electron microscope with backscattered electron imaging ( SEM- BSE). In addition, chemical analysis and elemental mapping of the mineral composition were generated using a microanalytical system based on energy-dispersive X-ray spectrometry ( EDX). Results No clinical complications occurred during surgery. Scanning electron microscopy revealed that newly formed bone was closely attached to the xenograft. Elemental analysis showed a significantly high Ca/ P ratio in the residual biomaterials (3.031 ± 0.104) compared with the interface (2.908 ± 0.115) and new bone (2.889 ± 0.113), which suggests that there may be a gradual diffusion of Ca ions from the biomaterial into the newly forming bone at the interface as part of the biomaterial's resorption process. EDX analysis of the residual bovine biomaterial showed particle categories with different mean Ca/ P ratios according to size, pointing to different stages of the resorption process. Conclusions The biomaterial proved to be biocompatible and osteoconductive when used as a bone substitute for maxillary sinus elevation. The grafting material used is not a completely resorbable material over the time period covered by this study. [ABSTRACT FROM AUTHOR]