Mustafa Yal?ın/Beyza Kaya/Nihat La?in/Emre Arı: Purpose: The aim of this study was to analyze stress distribution on four different implant designs and four different qualities of cortical bone surrounding the implant crest modules using three-dimensional finite element analysis. Materials and Methods: Four different implant designs of the same diameter and length (3.75 ± 11.5 mm) were used. Rhinoceros 4.0 3D modeling software was used for preparing the four types of bone quality (D1, D2, D3, and D4). Mandibular second premolar crowns were constructed as prosthetic superstructures of the implants, and a total force of 300 N was vertically applied to the crowns. Stress distribution on dental implants and cortical bone of D1, D2, D3, and D4 bone quality was evaluated. Results: Among all of the implants, the maximum von Mises stress value on cortical bone surrounding the neck region of the implants was found in D4 bone quality, while the minimum stress was detected in D1 bone quality. The stress distribution on the threads of dental implants exhibited the most homogeneous distribution in D1 bone quality, while higher von Mises stress values were observed in the apical blade segment of the implants in D3 and D4 bone quality. Conclusion: It was found that the maximum stress of cortical bone surrounding the implant crest module decreased as the bone density increased. The microthreads on the implant crest module might cause an increase in stress to cortical bone surrounding the neck region of implants.

Aim: To evaluate the prevalence, diameter, localization of the posterior superior alveolar artery (PSAA) and the relationship between PSAA and the floor of the maxillary sinus and the thickness of the maxillary sinus lateral wall using cone-beam computed tomography (CBCT). Material and Methods: In this retrospective study, more than 500 CBCT images were retrieved. Out of them 156 CBCT images were related to the sinus floor elevation, among which 120 CBCT images were enrolled in the study based on the inclusion criteria, and 36 CBCT images were excluded. A total of 120 CBCT images of the PSSA from 60 patients comprising 32 (53.3%) men and 28 (46.7%) women were analyzed. Statistical data were analyzed using SPSS for Windows version 22. Descriptive statistics (mean, standard deviation, frequency) were used for the analyses. Results: The ages of the participants ranged between 26 and 76 years and the mean age was 54.48 ± 10.92 years. The PSAA was detected on the right side in 95% of the CBCT scans and on the left side in 85% of the maxillary sinuses. At the first detection point (FDP) and last detection point (LDP), the mean values of the distance between the inferior border of the PSAA and the floor of the maxillary sinus were 9.54 ± 4.27 mm and 7.91 ± 4.75 mm, respectively. The mean diameters of the PSAA at the FDP and LDP were 1.36 ± 0.46 mm and 1.12 ± 0.35 mm, respectively. Conclusion: Detection of the characteristics of the PSAA by using CBCT is crucial for handling the sinus floor elevation procedures uneventfully.

The authors report a rare case of intraosseous hemangioma of the mandible in a 14-year-old male. Surgical intervention with embolization is as important as histological and radiological examination to reduce the bleeding complication. Magnetic resonance angiography is paramount of importance in these lesions to detect the supplier arteries.

Background: To determine whether degree of the nasal septum deviation (NSD) can affect the frequency of antral pseudocyst (AP) formation by cone beam computed tomography (CBCT). Materials and methods: This retrospective study was included 466 CBCT images. The NSD were categorized into four groups according to the degree: Control group (no NSD, 0°-2°), Group A (2°-9°), Group B (9°-15°), and Group C (≥15°). The predictor variables were demographic factors (patient’s age and gender) and anatomic factors (different degrees of nasal septum angulation). The outcome variable was presence of AP. Results: Of the 466 cases, 242 (51.9%) had no NSD, 66 (14.2%) had an angle of 2°-9°, 111 (23.8%) had an angle of 9°-15°, and 47 (10.1%) had an angle of over 15°. The prevalence of AP was 2.04 (95% CI, 1.37 to 3.03; p=0.001) times higher in the presence of NSD. Significant increases in presence of AP occurred with NSD in Group A (2.37 times higher; P=.003) and Group B (2.07 times higher; P=.003) compared to control by univariate analysis. Conclusions: Although there is no sufficient evidence to suggest that NSD is a definitive etiological factor for AP development, our findings indicated that NSD increased the risk of AP formation. Background: To determine whether degree of the nasal septum deviation (NSD) can affect the frequency of antral pseudocyst (AP) formation by cone beam computed tomography (CBCT). Materials and methods: This retrospective study was included 466 CBCT images. The NSD were categorized into four groups according to the degree: Control group (no NSD, 0°-2°), Group A (2°-9°), Group B (9°-15°), and Group C (≥15°). The predictor variables were demographic factors (patient’s age and gender) and anatomic factors (different degrees of nasal septum angulation). The outcome variable was presence of AP. Results: Of the 466 cases, 242 (51.9%) had no NSD, 66 (14.2%) had an angle of 2°-9°, 111 (23.8%) had an angle of 9°-15°, and 47 (10.1%) had an angle of over 15°. The prevalence of AP was 2.04 (95% CI, 1.37 to 3.03; p=0.001) times higher in the presence of NSD. Significant increases in presence of AP occurred with NSD in Group A (2.37 times higher; P=.003) and Group B (2.07 times higher; P=.003) compared to control by univariate analysis. Conclusions: Although there is no sufficient evidence to suggest that NSD is a definitive etiological factor for AP development, our findings indicated that NSD increased the risk of AP formation.