Maxillary sinus septa increase the risk of membrane perforation during sinus floor elevation and grafting operations. This study was designed to evaluate the prevalence, morphology, localisation, ...aetiology, and orientation of maxillary sinus septa in dentate, completely edentulous, and partially edentulous sinus regions using cone beam computed tomography (CBCT), and possible patient-related factors were also assessed. Data from 300 patients (600 sinuses), 160 women and 140 men, with a mean (SD) age of 50.72 (13.99) years (range 20–83), who were undergoing treatment planning for implant-supported restorations in posterior maxillae, were analysed from reformatted CBCT scans. Sinus septa were detected in 132 (44%) patients. A total of 208 septa were found, and 187 (31.17%) single maxillary sinuses presented septa in 600 sinuses. Unilateral septa were found in 77 patients (58.3%) and bilateral septa in 55 patients (41.7%). Out of the 208 septa, 42 (20.19%) were in the anterior third, 124 (59.62%) were in the middle third, and 42 (20.19%) were in the posterior third. Further, 106 (50.96%) septa were in completely edentulous regions, 64 (30.77%) were in partially edentulous regions, and 38 (18.27%) were in dentate regions. The prevalence of septa was significantly higher in the middle third area of the completely edentulous sinus regions. The mean (SD) height of septa was 6.34 (3.05) mm, and the mean orientation was buccopalatal in 204 patients (98.08%). Maxillary sinus septa are common anatomical structures. To avoid possible complications during sinus augmentation, a detailed radiographic identification of anatomical structures in maxillary sinuses is needed.
Postoperative pain is well known and usually disturbing complication of surgery. Inflammation plays an important role in the development and progression of postoperative pain. We aimed to investigate ...possible relationship between preoperatively measured neutrophil-lymphocyte ratio (NLR) - as an inflammation marker - and postoperative analgesic demand in patients underwent orthognathic surgery.
We retrospectively investigated medical and anesthesia records of 177 patients underwent orthognathic surgery. Demographical data, preoperative NLR, type of surgery, modified Mallampati score, difficulty degree of intubation, duration of surgery, and postoperative analgesic (tenoxicam - as the first drug of choice, paracetamol, tramadol, or pethidine) usage were recorded. A cutoff value of NLR ≥2 was determined for inflammation threshold. Two groups (Group 1 NLR ≥2, Group 2 NLR <2) were compared for analgesic doses, numbers of patients needed analgesic treatment, and other parameters.
Mean administered tenoxicam dose was significantly higher in Group 1 than in Group 2 (P < 0.0001). Further, ratio of patients treated with tenoxicam in Group 1 was significantly higher than that in Group 2 (χ2 = 4.779, P = 0.029).
Preoperatively measured NLR may help to predict postoperative analgesic demand in patients undergoing orthognathic surgery, and thus sufficient postoperative pain control can be achieved with various preventive treatments taken at the perioperative period such as preemptive analgesia, local anesthetic administration at the end of surgery, or early administration of analgesics.
Objective: The aim of this study was to evaluate the mechanical behavior of different rigid fixation methods in mandibular angle fractures.
Materials and Methods: Three different three-dimensional ...finite element models of the mandible were developed to simulate the biomechanical responses of titanium plates and screws. The fracture lines were fixed with double 4-hole straight, 4-hole square, and 5-hole Y plates with monocortical screws. 150 N incisal occlusal loads were simulated on the models. The commercial ANSYS software was utilized to calculate the Von Mises stresses on fixative appliances.
Results: The highest Von Mises stress values were observed in the Y plate, whereas the lowest stress values have been found in the square plate.
Conclusions: The use of square plate led to better stability and lower mechanical stresses than other techniques.
Abstract The study aimed to calculate the location and intensity of the maximum stress fields on the fixation plates and surrounding maxilla following Le Fort I osteotomies after advancement ...procedures using three-dimensional finite element analysis. The models were generated using skull CT scan data. Le Fort I osteotomy simulations were made and two separate impacted maxillary models were designed. The ADV-2 model has 2 plate fixations bilaterally at the piriform rims, the ADV-4 model has 4 plate fixations at the zygomatic buttresses and piriform rims. The stress fields on bone, plate and screws were computed for each model. Posterior occlusal loads were simulated on one side in the molar–premolar region, in all three directions, reflecting the chewing forces. The increased locations of highest Von Mises stresses on the plates and highest maximum principle stresses on the bones were determined in ADV-2 models especially under horizontal and oblique loads when compared with ADV-4 models. Evaluation of the highest Von Mises stress values and maximum principal stress revealed that oblique load in the ADV-2 model received the highest values. 4-plate fixation following Le Fort I advancement surgery exerts less stress on the maxillary bones and fixation materials than 2-plate fixation.
Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work that introduced a strong spin-orbit interaction to the nuclear shell model potential. However, knowledge ...of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron-proton pairing, in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus (92)Pd. Gamma rays emitted following the (58)Ni((36)Ar,2n)(92)Pd fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution γ-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction. We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron-proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objective: The aim of the study was to evaluate the mechanical behavior of three different fixation methods used in the bilateral sagittal split ramus osteotomy.
Materials and Methods: Three ...different three-dimensional finite element models were created, each corresponding to three different fixation methods. The mandibles were fixed with double straight 4-hole, square 4-hole, and 5-hole Y plates.
150 N incisal occlusal loads were simulated on the distal segments. ANSYS software ((v 10; ANSYS Inc., Canonsburg, PA) was used to calculate the Von Mises stresses on fixative appliances.
Results: The highest Von Mises stress values were found in Y plate. The lowest values were isolated in double straight plate group.
Conclusions: It was concluded that the use of double 4-hole straight plates provided the sufficient stability on the osteotomy site when compared with the other rigid fixation methods used in this study.
Background and Aim: Selecting the optimum nasal passage for nasotracheal intubation is quite important in the maxillofacial surgeries for the success of intubation and the reduction of potential ...complications such as nasal mucosal laceration, epistaxis, avulsion of the inferior and middle turbinates, and septal laceration. Materials and Methods: The present study evaluates standard panoramic radiographs (PR) and posteroanterior cephalometric radiographs (PACR) to determine the optimal nasal passage for nasotracheal intubation and compares the results with those of routine anesthesiological occlusion and spatula tests (ST). The results of occlusion tests (OT), ST, and radiological assessments of 60 patients prior to nasotracheal intubation were compared with the nasal endoscopic assessment results, and complications were evaluated. Results: There was no significant association between the OT and nasal endoscopy results (P = 0.075). A significant association was found between the ST and nasal endoscopy results (P = 0.000), and between the radiological assessments and the nasal endoscopy results (P = 0.000). Compatibility with nasal endoscopy was 54% when the occlusion and ST were evaluated together, 75% when the OT and radiological assessments were evaluated together, and 86% when the ST and radiological assessments were evaluated together. The highest level of compatibility was 92% when all the tests were evaluated together. Conclusion: The simple tests alone were found to be inadequate for the selection of the optimal nasal passage. Evaluation of PR and PACR, which are commonly used in maxillofacial surgeries, together with simple anesthesiological examination tests would increase nasotracheal intubation success and decrease complications.
Abstract The aim of this study was to investigate and compare changes in the nasomaxillary complex substructures following orthopaedic rapid maxillary expansion (RME) and surgically assisted RME ...(SARME). 10 patients received RME, 10 patients received SARME, and 10 patients served as an untreated control group. Lateral and posteroanterior cephalograms were obtained for each individual at pre-expansion/pre-control (T1) and post-expansion/post-control (T2). Descriptive parameters and transversal measurements on maxillo-mandibular dentoalveolar structures and skeletal bases, right and left nasal cavity angles (NC/Lom/VL and CN/Lom/VL, respectively), total nasal cavity angle (NC/Lom/CN), nasal cavity width (NC-CN) and nasal septum angle (sn/Lom/VL) were also calculated. Paired t -tests were used to evaluate changes within groups following treatment/control. Analysis of variance (ANOVA) and Duncan's tests were used to compare changes between groups. With the exception of nasal septum deviation, all nasal parameters significantly increased following RME and SARME. The increases in the SARME group were greater than in the other groups, but no statistically significant differences were recorded between the RME and SARME groups. Neither RME nor SARME created positional changes in the nasal septum.
Background
SARS‐CoV‐2 virus requires host proteases to cleave its spike protein to bind to its ACE2 target through a two‐step furin‐mediated entry mechanism. Aprotinin is a broad‐spectrum protease ...inhibitor that has been employed as antiviral drug for other human respiratory viruses. Also, it has important anti‐inflammatory properties for inhibiting the innate immunity contact system.
Methods
This was a multicentre, double‐blind, randomized trial performed in four Spanish hospitals comparing standard treatment versus standard treatment + aprotinin for patients with COVID‐19 between 20 May 2020 and 20 October 2021. The primary efficacy outcomes were length of hospital stay and ICU admission. The secondary endpoints were each of the primary efficacy outcomes and a composite of oxygen therapy, analytical parameters and death. Safety outcomes included adverse reactions to treatment during a 30‐day follow‐up period. Treatment was given for 11 days or till discharge.
Results
With almost identical analytical profiles, significant differences were observed in treatment time, which was 2 days lower in the aprotinin group (p = .002), and length of hospital admission, which was 5 days shorter in the aprotinin group (p = .003). The incidence of discharge was 2.19 times higher (HR: 2.188 1.182–4.047) in the aprotinin group than in the placebo group (p = .013). In addition, the aprotinin‐treated group required less oxygen therapy and had no adverse reactions or side effects.
Conclusion
Inhaled aprotinin may improve standard treatment and clinical outcomes in hospitalized patients with COVID‐19, resulting in a shorter treatment time and hospitalization compared with the placebo group. The administration of aprotinin was safe.
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