Prevalence and location of the posterior superior alveolar artery using cone-beam computed tomography

PURPOSE: Insufficient knowledge of the anatomy of the maxillary sinuses prior to sinus graft surgery may lead to perioperative or postoperative complications. This study sought to characterize the position of the posterior superior alveolar artery (PSAA) within the maxillary sinuses using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 300 patients with edentulous posterior maxillae, including 138 females and 162 males with an age range of 33-86 years, who presented to a radiology clinic between 2013 and 2015 were enrolled in this retrospective cross-sectional study. The distance from the inferior border of the PSAA to the alveolar crest according to the residual ridge classification by Lekholm and Zarb, the distance from the PSAA to the nasal septum and zygomatic arch, and the diameter and position of the PSAA were all assessed on patients' CBCT scans. The data were analyzed using the Mann-Whitney test and the t-test. RESULTS: The PSAA was detected on the CBCT scans of 87% of the patients; it was located beneath the sinus membrane in 47% of cases and was intraosseous in 47% of cases. The diameter of the artery was between 1 and 2 mm in most patients (72%). The mean diameter of the artery was 1.29±0.39 mm, and the mean distances from the PSAA to the zygomatic arch, nasal septum, and alveolar crest were 22.59±4.89 mm, 26.51±3.52 mm, and 16.7±3.96 mm, respectively. CONCLUSION: The likelihood of detecting the PSAA on CBCT scans is high; its location is intraosseous or beneath the sinus membrane in most patients. Determining the exact location of the PSAA on CBCT scans preoperatively can help prevent it from being damaged during surgery.

in vitro assessment of antimicrobial and cytotoxic effects of nanosilver

The antimicrobial activity of silver nanoparticles has been investigated in medical fields in recent years, but there are few studies regarding its effect on oral microorganisms. The aim of the present study was to evaluate the in vitro antimicrobial and toxicity properties of nanosilver against two dental plaque microorganisms and Human Gin-gival Fibroblast [HGF] cell line. Antibacterial effects of nanosilver colloidal solution were determined by minimal inhibitory concentration [MIC] and minimal bactericidal concentration [MBC] using microdilution method. Standard strains of Streptococcus sanguis and Actinomyces viscosus were used. For toxicity assessment, MTT and LDH tests were performed under controlled conditions. Different concentrations of nanosilver were prepared and their toxic effects on HGF were determined after 24, 48 and 72 hours. The MIC of nanosilver solution for S. sanguis and A. viscosus were 16 and 4 microg/ml, respectively. The MBC of nanosilver was 64 microg/ml for S. sanguis and 16 microg/ml for A. viscosus. MTT results showed that after 24 hours the concentrations of > 0.5 microg/ml of nanosilver solution affected cell viability when compared with control group. After 48 and 72 hours only the concentration of > 5 microg/ml showed significant effect on cultured cell viability. LDH release test demonstrated toxic effect only after 48, 72 hours by 20 and 50 microg/ml of nanosilver. The results demonstrated that beside its antibacterial activity against S. sanguis and A. viscosus, nanosilver mediated a concentration and time dependent cytotoxicity on HGF