Browsing by Author "Rakocevic, Zoran (57197600169)"

Although seen frequently during dissections and autopsies, Hyperostosis frontalis interna (HFI) – a morphological pattern of the frontal bone thickening – is often ignored and its nature and development are not yet understood sufficiently. Current macroscopic classification defines four grades/stages of HFI based on the morphological appearance and size of the affected area; however, it is unclear if these stages also depict the successive phases in the HFI development. Here we assessed 3D-microarchitecture of the frontal bone in women with various degrees of HFI expression and in an age- and sex-matched control group, hypothesizing that the bone microarchitecture bears imprints of the pathogenesis of HFI and may clarify the phases of its development. Frontal bone samples were collected during routine autopsies from 20 women with HFI (age: 69.9 ± 11.1 years) and 14 women without HFI (age: 74.1 ± 9.7 years). We classified the HFI samples into four groups, each group demonstrating different macroscopic type or stage of HFI. All samples were scanned by micro-computed tomography to evaluate 3D bone microarchitecture in the following regions of interest: total sample, outer table, diploe and inner table. Our results revealed that, compared to the control group, the women with HFI showed a significantly increased bone volume fraction in the region of diploe, along with significantly thicker and more plate-like shaped trabeculae and reduced trabecular separation and connectivity density. Moreover, the inner table of the frontal bone in women with HFI displayed significantly increased total porosity and mean pore diameter compared to controls. Microstructural reorganization of the frontal bone in women with HFI was also reflected in significantly higher porosity and lower bone volume fraction in the inner vs. outer table due to an increased number of pores larger than 100 μm. The individual comparisons between the control group and different macroscopic stages of HFI revealed significant differences only between the control group and the morphologically most pronounced type of HFI. Our microarchitectural findings demonstrated clear differences between the HFI and the control group in the region of diploe and the inner table. Macroscopic grades of HFI could not be distinguished at the level of bone microarchitecture and their consecutive nature cannot be supported. Rather, our study suggests that only two different types of HFI (moderate and severe HFI) have microstructural justification and should be considered further. It is essential to record HFI systematically in human postmortem subjects to provide more data on the mechanisms of its development. © 2016 Anatomical Society

Although seen frequently during dissections and autopsies, Hyperostosis frontalis interna (HFI) – a morphological pattern of the frontal bone thickening – is often ignored and its nature and development are not yet understood sufficiently. Current macroscopic classification defines four grades/stages of HFI based on the morphological appearance and size of the affected area; however, it is unclear if these stages also depict the successive phases in the HFI development. Here we assessed 3D-microarchitecture of the frontal bone in women with various degrees of HFI expression and in an age- and sex-matched control group, hypothesizing that the bone microarchitecture bears imprints of the pathogenesis of HFI and may clarify the phases of its development. Frontal bone samples were collected during routine autopsies from 20 women with HFI (age: 69.9 ± 11.1 years) and 14 women without HFI (age: 74.1 ± 9.7 years). We classified the HFI samples into four groups, each group demonstrating different macroscopic type or stage of HFI. All samples were scanned by micro-computed tomography to evaluate 3D bone microarchitecture in the following regions of interest: total sample, outer table, diploe and inner table. Our results revealed that, compared to the control group, the women with HFI showed a significantly increased bone volume fraction in the region of diploe, along with significantly thicker and more plate-like shaped trabeculae and reduced trabecular separation and connectivity density. Moreover, the inner table of the frontal bone in women with HFI displayed significantly increased total porosity and mean pore diameter compared to controls. Microstructural reorganization of the frontal bone in women with HFI was also reflected in significantly higher porosity and lower bone volume fraction in the inner vs. outer table due to an increased number of pores larger than 100 μm. The individual comparisons between the control group and different macroscopic stages of HFI revealed significant differences only between the control group and the morphologically most pronounced type of HFI. Our microarchitectural findings demonstrated clear differences between the HFI and the control group in the region of diploe and the inner table. Macroscopic grades of HFI could not be distinguished at the level of bone microarchitecture and their consecutive nature cannot be supported. Rather, our study suggests that only two different types of HFI (moderate and severe HFI) have microstructural justification and should be considered further. It is essential to record HFI systematically in human postmortem subjects to provide more data on the mechanisms of its development. © 2016 Anatomical Society

To improve our understanding of hyperostosis frontalis interna (HFI), we investigated whether HFI was accompanied by changes in the postcranial skeleton. Based on head CT scan analyses, 103 postmenopausal women were divided into controls without HFI and those with HFI, in whom we measured the thickness of frontal, occipital, and parietal bones. Women in the study underwent dual energy x-ray absorptiometry to analyze the bone density of the hip and vertebral region and external geometry of the proximal femora. Additionally, all of the women completed a questionnaire about symptoms and conditions that could be related to HFI. Women with HFI had a significantly higher prevalence of headaches, neurological and psychiatric disorders, and a significantly lower prevalence of having given birth. Increased bone thickness and altered bone structure in women with HFI was localized only on the skull, particularly on the frontal bone, probably due to specific properties of its underlying dura. Bone loss in the postcranial skeleton showed the same pattern in postmenopausal women with HFI as in those without HFI. Recording of HFI in medical records can be helpful in distinguishing whether reported disorders occur as a consequence of HFI or are related to other diseases, but does not appear helpful in identifying women at risk of bone loss. © 2016 Taylor & Francis.

The aim of the present study was to investigate the influences of the presence and position of a lower third molar (M3) on the fragility of mandibular angle and condyle, using finite element analysis. From computed tomographic scans of a human mandible with normally erupted M3, two additional virtual models were generated: a mandibular model with partially impacted M3 and a model without M3. Two cases of impact were considered: a frontal and a lateral blow. The results are based on the chromatic analysis of the distributed von Mises and principal stresses, and calculation of their failure indices. In the frontal blow, the angle region showed the highest stress in the case with partially impacted M3, and the condylar region in the case without M3. Compressive stresses were dominant but caused no failure. Tensile stresses were recorded in the retromolar areas, but caused failure only in the case with partially impacted M3. In the lateral blow, the stress concentrated at the point of impact, in the ipsilateral and contralateral angle and condylar regions. The highest stresses were recorded in the case with partially impacted M3. Tensile stresses caused the failure on the ipsilateral side, whereas compressive stresses on the contralateral side. © 2015 European Association for Cranio-Maxillo-Facial Surgery.

The aim of the present study was to investigate the influences of the presence and position of a lower third molar (M3) on the fragility of mandibular angle and condyle, using finite element analysis. From computed tomographic scans of a human mandible with normally erupted M3, two additional virtual models were generated: a mandibular model with partially impacted M3 and a model without M3. Two cases of impact were considered: a frontal and a lateral blow. The results are based on the chromatic analysis of the distributed von Mises and principal stresses, and calculation of their failure indices. In the frontal blow, the angle region showed the highest stress in the case with partially impacted M3, and the condylar region in the case without M3. Compressive stresses were dominant but caused no failure. Tensile stresses were recorded in the retromolar areas, but caused failure only in the case with partially impacted M3. In the lateral blow, the stress concentrated at the point of impact, in the ipsilateral and contralateral angle and condylar regions. The highest stresses were recorded in the case with partially impacted M3. Tensile stresses caused the failure on the ipsilateral side, whereas compressive stresses on the contralateral side. © 2015 European Association for Cranio-Maxillo-Facial Surgery.

Although the concept of the occlusal load transfer through the facial skeleton along the buttresses has been extensively studied, there has been no study to link microarchitecture of the mid-facial bones to the occlusal load distribution. The aim of this study was to analyze micro-structural properties of the mid-facial bones in relation to occlusal stress. The study was performed by combining the three-dimensional finite element analysis (3D FEA) and micro-computed tomography analysis (micro-CT). Clenching was simulated on the computer model of the adult male human skull which was also used as a source of bone specimens. After the FEA was run, stress was measured at the specific sites in cortical shell and trabecular bone of the model along and between the buttresses. From the corresponding sites on the skull, twenty-five cortical and thirteen cancellous bone specimens were harvested. The specimens were classified into high stress or low stress group based on the stress levels measured via the FEA. Micro-architecture of each specimen was assessed by micro-CT. In the high stress group, cortical bone showed a tendency toward greater thickness and density, lower porosity, and greater pore separation. Stress-related differences in microstructure between the groups were more pronounced in trabecular bone, which showed significantly greater bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) in the high stress group. Our results suggest that the mid-facial bones in the adult dentate male skull exhibit regional variations in cortical and trabecular bone micro-architecture that could be a consequence of different occlusal stress. © 2014 Elsevier Inc.

Although the concept of the occlusal load transfer through the facial skeleton along the buttresses has been extensively studied, there has been no study to link microarchitecture of the mid-facial bones to the occlusal load distribution. The aim of this study was to analyze micro-structural properties of the mid-facial bones in relation to occlusal stress. The study was performed by combining the three-dimensional finite element analysis (3D FEA) and micro-computed tomography analysis (micro-CT). Clenching was simulated on the computer model of the adult male human skull which was also used as a source of bone specimens. After the FEA was run, stress was measured at the specific sites in cortical shell and trabecular bone of the model along and between the buttresses. From the corresponding sites on the skull, twenty-five cortical and thirteen cancellous bone specimens were harvested. The specimens were classified into high stress or low stress group based on the stress levels measured via the FEA. Micro-architecture of each specimen was assessed by micro-CT. In the high stress group, cortical bone showed a tendency toward greater thickness and density, lower porosity, and greater pore separation. Stress-related differences in microstructure between the groups were more pronounced in trabecular bone, which showed significantly greater bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) in the high stress group. Our results suggest that the mid-facial bones in the adult dentate male skull exhibit regional variations in cortical and trabecular bone micro-architecture that could be a consequence of different occlusal stress. © 2014 Elsevier Inc.

Understanding of the occlusal load distribution through the mid-facial skeleton in natural dentition is essential because alterations in magnitude and/or direction of occlusal forces may cause remarkable changes in cortical and trabecular bone structure. Previous analyses by strain gauge technique, photoelastic and, more recently, finite element (FE) methods provided no direct evidence for occlusal load distribution through the cortical and trabecular bone compartments individually. Therefore, we developed an improved three-dimensional FE model of the human skull in order to clarify the distribution of occlusal forces through the cortical and trabecular bone during habitual masticatory activities. Particular focus was placed on the load transfer through the anterior and posterior maxilla. The results were presented in von Mises stress (VMS) and the maximum principal stress, and compared to the reported FE and strain gauge data. Our qualitative stress analysis indicates that occlusal forces distribute through the mid-facial skeleton along five vertical and two horizontal buttresses. We demonstrated that cortical bone has a priority in the transfer of occlusal load in the anterior maxilla, whereas both cortical and trabecular bone in the posterior maxilla are equally involved in performing this task. Observed site dependence of the occlusal load distribution may help clinicians in creating strategies for implantology and orthodontic treatments. Additionally, the magnitude of VMS in our model was significantly lower in comparison to previous FE models composed only of cortical bone. This finding suggests that both cortical and trabecular bone should be modeled whenever stress will be quantitatively analyzed. © 2014 Elsevier GmbH.

Understanding of the occlusal load distribution through the mid-facial skeleton in natural dentition is essential because alterations in magnitude and/or direction of occlusal forces may cause remarkable changes in cortical and trabecular bone structure. Previous analyses by strain gauge technique, photoelastic and, more recently, finite element (FE) methods provided no direct evidence for occlusal load distribution through the cortical and trabecular bone compartments individually. Therefore, we developed an improved three-dimensional FE model of the human skull in order to clarify the distribution of occlusal forces through the cortical and trabecular bone during habitual masticatory activities. Particular focus was placed on the load transfer through the anterior and posterior maxilla. The results were presented in von Mises stress (VMS) and the maximum principal stress, and compared to the reported FE and strain gauge data. Our qualitative stress analysis indicates that occlusal forces distribute through the mid-facial skeleton along five vertical and two horizontal buttresses. We demonstrated that cortical bone has a priority in the transfer of occlusal load in the anterior maxilla, whereas both cortical and trabecular bone in the posterior maxilla are equally involved in performing this task. Observed site dependence of the occlusal load distribution may help clinicians in creating strategies for implantology and orthodontic treatments. Additionally, the magnitude of VMS in our model was significantly lower in comparison to previous FE models composed only of cortical bone. This finding suggests that both cortical and trabecular bone should be modeled whenever stress will be quantitatively analyzed. © 2014 Elsevier GmbH.

Background: Developmental disturbances of the paranasal sinuses are proposed as the cause of osteoma. We examined whether such disturbances may result in the frequent presence of anatomical variations of the paranasal sinuses in patients with osteoma. Methodology/Principal: The study was performed retrospectively on 2,820 patients subjected to CT examination during 2005 - 2011. Demographic and CT characteristics of osteoma, and associated pathological lndings were evaluated for 104 patients with diagnosed osteoma. The presence of anatomical variations was assessed for 51 osteoma patients with a complete medical history, and for 1,233 patients from a control group. Results: The prevalence of osteomas was found to be 3.69%, with male to female ratio 1.08:1. The frontal sinus was most commonly aected. The presence of anatomical variations was more frequent in patients with osteoma than in controls, with signi!cant dierences con!rmed for the sphenomaxillary plate, infraorbital cell, and crista galli pneumatization. Conclusions: The paranasal sinus osteoma is associated with higher prevalence of anatomical variations. This can be explained either by the stronger in#uence of genetic and/or environmental factors on the development of the paranasal sinuses in patients with osteoma, or by their higher susceptibility to abovementioned factors.

Dysbiosis of the microbiome on the airway mucosa leads to the development of chronic inflammatory and allergic disorders. The aim of this study was to consider the potential diagnostic criteria for allergic fungal rhinosinusitis (AFRS) and nonallergic fungal rhinosinusitis (FRS), and the role of fungal presence in an environment for the development of AFRS. In this study, 136 patients were divided into two groups: patients with positive specific immunoglobulin E (sIgE) and fungal finding (AFRS group), and patients with negative sIgE and positive fungal finding (FRS group). The study design included: anamnesis data, sIgE, eosinophil count and skin-prick test, rhinology and computerized tomography (CT) observation and mycological finding. Our results showed: (i) the prevalence in Serbia is: AFRS 1.3%, FRS 2.8%; (ii) 30.4% patients with sIgE+ had more often severe and recurrent chronic rhinosinusitis (CRS) (P = .005) and the presence of polyps (P = .025); (iii) 46.4% patients with sIgE+ had positive fungi on the sinonasal mucosa and were considered as AFRS; (iv) patients with AFRS had more frequent asthma (P = .024) and chronicity of CRS >10 years (P = .000). The persistent fungal presence and prolonged duration of CRS could be a silent threat for the progression of inflammation and development of FRS. Lavage with hypertonic-NaCl should be included in the everyday hygiene routine in an effort to decrease fungal load and antigenic exposure. The presence of allergological parameters and better response to corticosteroid therapy in AFRS patients should be considered as crucial diagnostic criteria for AFRS. © The Author 2017.

Background: The analysis of morphometric right-left symmetry of the salivary glands is important for assessing unilateral changes discovered in these organs during diagnostic imaging. Study design: A study was carried out on 18 adult human autopsy neck and maxillofacial specimens from both sexes (14 males, 4 females), with age range of 17 to 73 years (mean age 49.9 years). The submandibular duct was injected with contrast medium and images were made in two projection planes. Results: Morphometry performed using the obtained radiographs included: (a) caliber (mean proximal, middle, and distal = 1.73 mm, 1.82 mm, and 1.77 mm), (b) length (mean = 37.2 mm); (c) genu of the submandibular duct (mean = 114°); and (d) longitudinal and transverse diameters of the gland (mean = 44.1 mm and 25.9 mm). Comparison of these morphometric parameters between the right and the left glands revealed no statistically significant differences. Conclusion: There is a high level of right-left symmetry in linear morphometric parameters of the submandibular gland. © 2006 Mosby, Inc. All rights reserved.

Background: The analysis of morphometric right-left symmetry of the salivary glands is important for assessing unilateral changes discovered in these organs during diagnostic imaging. Study design: A study was carried out on 18 adult human autopsy neck and maxillofacial specimens from both sexes (14 males, 4 females), with age range of 17 to 73 years (mean age 49.9 years). The submandibular duct was injected with contrast medium and images were made in two projection planes. Results: Morphometry performed using the obtained radiographs included: (a) caliber (mean proximal, middle, and distal = 1.73 mm, 1.82 mm, and 1.77 mm), (b) length (mean = 37.2 mm); (c) genu of the submandibular duct (mean = 114°); and (d) longitudinal and transverse diameters of the gland (mean = 44.1 mm and 25.9 mm). Comparison of these morphometric parameters between the right and the left glands revealed no statistically significant differences. Conclusion: There is a high level of right-left symmetry in linear morphometric parameters of the submandibular gland. © 2006 Mosby, Inc. All rights reserved.