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Ovarian cancer forms 4% of all cancers and approximately 23% of all gynecological cancers in women and is responsible for the 47% of deaths related to cancers of the genital tract of women. Tumor markers are the biochemical substances which can be detected in the presence of tumors. Generally they are either the products of tumoral tissues or secreted from the normal cells which are in the interaction with tumoral ones. The present authors attempted to determine the efficacy of the tumor marker CA-125 and HE4 to differentiate the malign cases from the benign adnexal masses. A total of 76 patients with the appropriate criteria were included in the study. They were divided into three groups; healthy control group (n=31), ones with benign masses (n=23), and ones with malign ovarian masses (n=22). In the study, when the cut-off values were accepted as 55I U/ml for CA-125 and 150 pM for HE4 in differentiation of benign and malign groups, the sensitivity was found as 59.09%, specificity 91.3%, PPV 86.67% and NPV 70% LR = +6.8. This combination gives one false positive result to every five positive cases which were detected as high. With the combination of CA-125 and HE4, the value of sensitivity was found decreased as expected, although the value of the specificity increased. [ABSTRACT FROM AUTHOR]

Abstract: Having studied the effect of maxillary advancement and maxillary impaction in parts 1 and 2 of this research, the purpose of this study was to investigate the biomechanical behavior of different fixation models in inferiorly and anteriorly repositioned maxilla following Le Fort I osteotomy. Two separate three-dimensional finite element models, simulating the inferiorly advanced maxilla at Le Fort I level, were used to compare 2- and 4-plate fixation. Model INF-2 resulted in 247897 elements and 53247 nodes and INF-4 consisted of 273130 elements and 59917 nodes. The stresses occurring in and around the bone and plate–screw complex were computed. The highest Von Mises stresses on the plates and maximum principal stresses on the bones were found in INF-2, especially under horizontal and oblique loads, when compared with INF-4. The present biomechanical study shows that the traditionally used 4-plate fixation technique, following Le Fort I inferior and anterior repositioning surgery, without bone grafting, provides fewer stress fields on the maxillary bones and fixation materials. [Copyright &y& Elsevier]

Abstract: The aim of the second part of this study was to evaluate the mechanical behaviour of 2- versus 4-plate fixation and bony structures after Le Fort I impaction surgeries using three-dimensional finite element analysis (3D-FEA). Two 3D-FEA models were created to fixate the impacted maxilla at the Le Fort I level as 2-plate fixation at the piriform rims (IMP-2 model) and 4-plate fixation at the zygomatic buttresses and piriform rims (IMP-4 model). The IMP-2 model contained 225664 elements and 48754 nodes and the IMP-4 model consisted of 245929 elements and 53670 nodes. The stresses in each maxillary model were computed. The models were loaded on one side, at the molar–premolar region, in vertical, horizontal and oblique directions to reflect the chewing process. It was concluded that the use of 4-plate fixation following Le Fort I advancement surgery provides fewer stress fields on the maxillary bones and fixation materials than 2-plate fixation from a mechanical point of view. [Copyright &y& Elsevier]

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. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to evaluate the mechanical behavior of different fixation methods used in bilateral sagittal split ramus osteotomy (BSSRO). Part 1 comprises of the results of the analysis for mandibular advancement, four different fixation configurations of six hole fragmentation mini plates with monocortical screws and lag screws and posterior loading conditions in the molar and premolar region. The finite element analysis method (FEA) appears suitable for simulating complex mechanical stress situations in the maxillofacial region. The mechanical behavior of selected lag screws with linear or triangular configuration and double parallel or single oblique six hole mini plates with monocortical screws were compared by FEA after 5mm BSSRO advancement procedure. Four separate three-dimensional finite element models of the mandible were created to simulate the BSSRO and corresponding fixation methods. These models consisted of 122,717 elements and 25,048 nodes. The mechanical parameters of the materials studied were adopted from the literature or were based on manufacturer''s information. 500 N posterior occlusal loads were simulated on the distal segments. The commercial finite element solver MSC Marc software was utilized to calculate the stress fields on both the segments and fixative appliances. It was concluded that the use of 2.0mm lag screws placed in a triangular configuration following the BSSRO advancement surgery provides sufficient stability with any rotational movement and less stress fields at the osteotomy site, when compared with the other rigid fixation methods used in the current study. [Copyright &y& Elsevier]

Abstract: Chondrosarcomas are the malignant cartilagenous tumors and they are seen rarely in the head and neck area. They are usually slow growing lesions. The head and neck chondrosarcomas may show an aggressive course and the occurrence of this malignant cartilagenous tumor in the parapharyngeal space is only a few. They are mostly located in relation with jaw bones and base of the skull. Chondrosarcomas of the parapharyngeal space are limited in number and among them there is no low-grade one. In this case report, a case of low-grade chondrosarcoma which was treated with a simple excision without neck dissection was reported. [Copyright &y& Elsevier]