Dry Human Skulls Research Articles

Study of pterion and asterion in adult human skulls of north Gujarat region

Introduction: The floor of the temporal fossa is bounded superiorly by the frontal and parietal bones and inferiorly by the greater wing of the sphenoid and squamous part of the temporal bone. All four bones of one side meet at a around H-shaped sutural junction known as Pterion. Asterion found at the junction of the lambdoid, occipitomastoid and parietomastoid sutures. Materials and Methods: 110 dry human adult aged skull of unknown sex without any gross pathology or abnormality were studied. Sutural pattern of the pterion was observed on both sides of each skull. The sutural pattern of pterion was classified as per Murphy’s criteria, into 4 types – sphenoparietal, frontotemporal, epipteric or stellate. On both sides of each skull, the sutural pattern of the asterion was classified into type I and type II. Result: Sphenoparietal was the most common type of pterion observed, 80.9% of total pterion. Epipteric was the least common type of pterion observed, 8.18% of total pterion. Frontotemporal was not observed in any skull. Sphenoparital, stellate and epipteric type of pterion shows bilateral symmetry. Most common type of asterion observed to be type II, found in 91.18% of total asterion. Bilateral symmetry only found in type II asterion. Conclusion: Observations of our study may be applicable with other commonly used method like radiological analysis for better prediction of different type of sutural morphology. Knowledge of sutural morphology may helpful for better surgical safety and efficacy. Keywords: Pterion, Asterion, Skull, Suture.

Determination of the accuracy of imaging methods to evaluate bone in maxilla for implant placement- An invitro study

Introduction: Dental implants are now treatment of choice in replacing of missing teeth. Treatment outcomes with dental implants are predictable and favourable. Long term implant survival is dependent on proper implant planning and case selection. Precision in dental implant placement is the sine qua non for dental implant success. Radiographic examinations are the only non-invasive technique for visualizing the bone topography, volume and location of vital structures like mandibular canal and maxillary sinuses. In this study we have tried to evaluate commonly used radiographic modalities in implant planning, orthopantomograph (OPG) and computed tomography (CT) and tried to compare their accuracy with direct measurements with skull sectioning at predetermined maxillary first molar region. Materials and Methods: Ten dry human skulls were subjected to OPG, CT and skull sectioning respectively. Measurements on height and width of the alveolar bone were noted at the maxillary first molar region and results were compared. Results: The mean height of alveolar bone measured using OPG, CT and Skull sectioning was found to be 12mm, 9.4mm and 9.3mm respectively. The mean value of width of alveolar bone measured using CT and skull sectioning was found to be equal at 10.3mm. Additionally, the mean rate of magnification for OPG was found to be 40%, whereas for CT it was just 2%. Keywords: Orthopantomography, Computed tomography, Dental Implants, Maxillary sinus.

Occipital condyles and its relation with hypoglossal canal: Anatomical study in central Indian population

Introduction: For transcondylar approach, most relevant step during surgical process is the resection of OC. Also it is important to have knowledge about it relevant anatomy and its relation with hypoglossal canal. This helps to avoid any iatrogenic injury during craniovertebral surgeries. Aims: The present study helps us to understand the morphological and morphometric data of occipital condyles and its relation with hypoglossal canal and its importance in transcondylar approach. Materials and Methods: The study was performed on 85 adult human dry skulls of unknown age and sex, obtained from Dept. of Anatomy, LNMC& JK hospital, Bhopal, India. Manual vernier calliper was used for the measurement. The length of the OC was measured. Also its shape was noted. In addition to all this, the different location of hypoglossal canal in relation to OC were assessed. Statistical Analysis: Mean and standard deviation of the parameters were analysed. Comparision was made of left and right side using unpaired t test and p value was calculated. Percentage of location of hypoglossal canal was calculated in relation with occipital condyles. Results: The mean of the length of occipital condyle on right side were found to be 21.24 mm and on left side 20.71 mm. The most common shape was quadrilateral type. The most common location of intracranial orifice of hypoglossal canal was located at location 4 and extracranial orifice was detected at location 3. Conclusion: All these parameters will be useful for performing various transcondylar surgical approaches and for reaching lesions in middle and posterior part of cranial base. Keywords: Occipital condyles, Hypoglossal canal, Transcondylar approach, Morphometry.

A STUDY ON THE OCCURRENCE OF WORMIAN BONES IN ADULT DRY SKULLS

Background: Sutural or wormian bones are islands of bone that are commonly found in the sutures of the skull mainly along the lambdoid suture. These sutural bones which are irregular in size, shape and number may arise from separate centres of ossification. The prior knowledge about the Wormian bones is important because they are present in normal individuals as well as in various disorders such as osteogenesis imperfect, rickets, etc. Aim: To study the occurence of wormian bones in adult dry skulls Materials and Methods: The present study was carried out on 95 adult dry human skulls in the department of Anatomy, Adichunchanagiri Institute of Medical Sciences, B G Nagara. Skulls with fractures and deformities were excluded from the study. Intact skulls were cleaned thoroughly and observed for the presence of wormian bones along the sutures of skull. Results: Out of 95 skull bones studied, 24 (25.26%) skulls showed the presence of wormian bones. We also observed that maximum number of such bones (single or multiple) were present along the lambdoid suture followed by lambda, asterion, sagittal suture & coronal suture. A very small wormian bone was also found near the bregma of the skull. Conclusion: The awareness about the occurrence of wormian bones and their topographical distribution will guide the clinicians mainly neurosurgeons in their practice. These bones mimic fracture lines in radiograph; therefore radiologists must also be aware of this normal variation. KEY WORDS: Wormian bone, Lambdoid suture, skull.

Biometric analysis of the area of the foramen magnum using the ImageJ software, and its correlation with the Radinsky and Teixeira formulas

Introduction: The knowledge of biometrics in the area of the foramen magnum is of importance in the pathophysiology of several disorders of the craniocervical junction, as well as for anthropology, anatomy and forensic medicine. The analysis of the area using image technology is still very scarce in the literature. Objective: Determine the area of the foramen magnum using ImageJ and correlate it with the areas calculated by the formulas of Radinsky and Teixeira. Methodology: 104 human dry skulls of adults were studied, 62 male and 42 female, belonging to the anatomy laboratories of the Universities: Tiradentes (UNIT) and Federal de Sergipe (UFS). To calculate the area of the foramen magnum, the ImageJ software was used, while the measures, length and width, were performed using a digital caliper. The areas calculated by ImageJ were compared to those calculated using the Radinsky and Teixeira formula. Results: The area of the foramen magnum measured by ImageJ ranged from 532.14 to 1135.79mm², with an overall average of 758.71mm². According to Radinsky's formula, the area of the foramen magnum varied from 610.35 to 1233.09mm², with an average of 828.25mm²; and in Teixeira, the area ranged from 633.67 to 1241.29mm², with an average of 840.16mm². The Cronbach's alpha correlating the three methods was equal to 0.950. Conclusion: The calculation of the area of the foramen magnum, using the ImageJ software was significantly close to the area calculated by the formulas of Radinsky and Teixeira (Cronbach's alpha=0.950), proving to be useful for forensic practice. Sexual dismorphism can be found, varying its appearance in literature, but only in relation to its size, but not its shape. However some other authors seem to have not found any sexual dismorphism.

MORPHOLOGY AND MORPHOMETRIC ANALYSIS OF FORAMEN MAGNUM IN ADULT HUMAN SKULLS

Background: The Foramen magnum is an important landmark present at the base of the skull, it serves as a transitional zone between spine and skull. It is closely related to vital structures such as medulla oblongata, meninges, anterior and posterior spinal arteries, vertebral arteries and spinal accessory nerve, passing through it hence thorough knowledge of foramen magnum is required. These structures passing may undergo compression in case of foramen magnum herniation, meningiomas and foramen magnum achondroplasia. Aims: The present study aims in performing the morphometric analysis foramen magnum and to classify it based on its shape. Materials and methodology A total number of 64 adult dry human skulls were evaluated from the Department of Anatomy, ESIC MC & PGIMSR, Rajajinagar, Bengaluru, Karnataka. Results: The mean antero-posterior diameter was found to be 34.10 ± 2.63 mm, mean transverse diameter was 28.07 ± 1.87 mm, with mean area of 752.07 ± 111.97 mm2 and foramen magnum index was 1.21 ± 0.12. The foramen magnum shapes were classified as oval (30%), circle (12%), hexagonal (3%), pentagonal (5%), egg (17%), leaf (6%), irregular (27%). Conclusion: The morphometry along with other parameters can be used for sex determination in partially damaged skull bones of unknown individuals. The obtained data is useful not only for anatomists but also the neurosurgeons, otorhinolaryngologist and radiologists. Keywords: Foramen Magnum, Morphometry, Meningioma, Achondroplasia, Antero-Posterior Diameter, Transverse Diameter, Foramen Magnum Area, Foramen Magnum Index.

Existence of Foramen of Huschke In Human Dry Skulls

Existence of Foramen of Huschke In Human Dry Skulls

Sex determination through biauricular breadth and biasterionic breadth in dry human skull bones - A morphometric study

Sex determination through biauricular breadth and biasterionic breadth in dry human skull bones - A morphometric study

Morphological and Morphometric Analysis of Greater Palatine Foramen in Dry Human Skulls of South Indian Population

Morphological and Morphometric Analysis of Greater Palatine Foramen in Dry Human Skulls of South Indian Population

Morphometric Analysis of Cranial Base of South Indian Human Dry Skull

Morphometric Analysis of Cranial Base of South Indian Human Dry Skull

Influence of CBCT Different Voxel Sizes on Soft Tissue Thickness Measurement

Objective: The aim of this study is to assess the effect of different CBCT voxel sizes on the soft tissue thickness measurements in a variety of maxillary and mandibular regions. Methods: Two thicknesses (less than 2.0 mm and more than 2.0 mm) of pink baseplate wax as simulated soft tissue were overlaid on a maxilla and mandible of a dry human skull. The thicknesses were measured with a digital caliper as the physical measurements. The skull was scanned using CBCT with four different voxel sizes (0.20, 0.25, 0.30 and 0.4 mm). CBCT measurements were compared to the physical measurements. Intraclass Correlation Coefficient was used to assess both intra- and inter-observer reliability. Significance was considered to be 5% (P ≤ 0.05). Results: Results showed a significant difference between the CBCT measurements using the 0.3 and 0.4 mm voxel sizes scans compared to the physical measurements when wax thickness was less than 2.0 mm. On the other hand, no significant difference was found for the CBCT measurements using the four voxel sizes when thickness was greater than 2.0 mm. Conclusions: CBCT scans with voxel sizes of 0.3 mm and 0.4 mm provide accurate simulated soft tissue measurements when the thickness is more than 2.0 mm. However, when greater visualization of details are required, scans with lower voxel sizes is required. Therefore, in a clinical situation, it is of great importance to customize the resolution protocol according to the accuracy needed.

Dental Condition as A Factor Modifying the Transmission of the Sound Vibration in the Skull Bones

Dental deficiencies coexist with hearing loss, and dental treatment can improve hearing acuity. To prove that different dentition affects the transmission of acoustic vibrations through bone conduction, we prepared six dry human skulls to reconstruct teeth and soft tissues. We measured the transmission of vibrations from the maxilla to the cochlea, in the toothless jaw (TJ), jaw with lateral defects with frame dentures (FD), toothless jaw with complete dentures (CD), and jaw with reconstructed dentition (RD). Each skull was flexibly suspended. The maxilla was stimulated with the bone vibrator Radioear B71. The vibrations of the pyramid were measured perpendicularly using the Polytec PSV-400-M2 scanning vibrometer. Characteristics of frequencies differed simultaneously on the left (l) and right (r) side of each skull. In all states (from 234 Hz to 5 kHz), we identified 10–21 resonant (R) and 9–21 antiresonant (AR) frequencies unilaterally (+/− 5%). In about 30% of cases, they were each time inconsistent with the “physiological” state-RD. In the 500 Hz–2 kHz frequency range (necessary for understanding speech), the effective vibrations velocities vRMS (mm/s) near cochlea were significantly lower in RD than in tree states, where (depending on the dentures) the least energy reached cochlea in FD and the most in TJ.

Elongated styloid process in a dry human skull and its relation to the Eagle’s Syndrome: case report and biometrical assessment

The purpose of the present study was to report a case of an elongated styloid process in a dry human skull and present its biometrical values. The styloid processes of the skull from an 80-year-old Brazilian female individual were inspected and 10 measures were performed bilaterally. Despite small differences between the right and left styloid processes regarding the antero-posterior and lateral-medial widths on the three thirds measured, one must highlight the considerable differences showed on the total length of the styloid process (left side: 65.94; right side: 28.90) and on the length of the sheath of the styloid process, which was of 30.01mm on the left side and it was not acquired on the right side because of its small dimensions. The paper discusses its findings from an anatomical and clinical perspectives, providing anatomical basis for a better understanding of the Eagle’s syndrome.

Sex determination using mastoid length and biasterionic breath in dry human skulls - A morphometric analysis

Sex determination using mastoid length and biasterionic breath in dry human skulls - A morphometric analysis

Incidence and clinical relevance of pterygospinous bar and pterygoalar bridges in dry human skulls

Incidence and clinical relevance of pterygospinous bar and pterygoalar bridges in dry human skulls

Sex determination by basion-nasospinale length and cranial base length in dry human skull bones - A morphometric study

Sex determination by basion-nasospinale length and cranial base length in dry human skull bones - A morphometric study

Morphological and Morphometrical Analysis of Glasscock’s Triangle and Its Clinical Applications in Dry Human Skull Bones

Morphological and Morphometrical Analysis of Glasscock’s Triangle and Its Clinical Applications in Dry Human Skull Bones

Comparative study of the accuracy of CBCT implant site measurements using different software programs

PurposeTo measure and compare the accuracy of the linear dimensions of implant sites recorded from cone beam computed tomography (CBCT) images using Blue Sky Plan, coDiagnostiX, and RadiAnt. Materials and MethodsFive human dry skulls were imaged with a CBCT device then sectioned to obtain sample transverse cross-sections of the edentulous ridges, and the height and width of the ridge were measured with a digital caliper to provide the gold standard measurements. The CBCT datasets were exported in DICOM format and imported into the three test software programs which were used to obtain reformatted sectional images corresponding to the sample transverse cross-sections, and the height and width of the edentulous ridge was recorded using the linear measurement tool. Reliability of the measurements were measured using the intraclass correlation coefficient. One-sample t-test (test value: zero) was used to test the statistical significance of the mean of the absolute errors for each software program. Analysis of Variance with Repeated Measures was used to test the statistical significance of the difference between the means of the absolute errors obtained by the different software programs. Statistical significance was set at a p-value of 0.05. ResultsThe reliability of the gold standard and image measurements were excellent. All three software programs demonstrated a statistically significant mean absolute measurement error of between 0.43 and 0.56 mm (p-value < 0.01), but no significant difference in error values was found between any of the tested programs (p- value = 0.18). ConclusionsThere was no statistically significant difference in accuracy of linear CBCT measurements of implant sites recorded using Blue Sky Plan, coDiagnostiX, and RadiAnt.

Surface Marker-Assisted for Orbital Navigation Surgery: A Dry Skull Study

The purpose of this study was to explore a surface marker-assisted method for orbital floor reconstruction. Six adults, dry human skulls were used in this study. First, an individualised, 0.4 mm aluminum orbital implant was prepared for orbital floor bilaterally. Four physical implant surface markers in the anterior and posterior aspects of the implant were created and subjected for an optical scan. Preoperative cone beam computed tomography (CBCT) scans were obtained for all orbital floors. The Digital Imaging and Communications in Medicine (DICOM) data were retrieved, imported and virtually reconstructed with its respective orbital implant stereolithography (STL) data by using iPlan CMF (Version 3.0, BrainLab, Germany). Navigation image-fusion technique was performed for each skull following navigation-assisted reconstruction and postoperative CBCT. Computed tomography (CT)-assisted measurements of the implant positions were evaluated between the virtually planned and realized implant positions in its translational differences sagittal and coronal planes. All statistical analysis was performed using PASW® Statistics Version 18. Results showed that38 out of the 48 surface markers evaluated showed a small elevation in realized compared to the virtual orbital implant position. Translation for the Euclidean metric showed differences of less than 1.00 mm in all surface markers except at the posterior ledge and anterior when assessed in the sagittal plane. The study showed that the placement of surface marker-assisted in orbital navigation surgery provides a consistent orbital implant position.

Fusion of intra-oral scans in cone-beam computed tomography scans

PurposeThe purpose of this study was to evaluate the clinical accuracy of the fusion of intra-oral scans in cone-beam computed tomography (CBCT) scans using two commercially available software packages.Materials and methodsTen dry human skulls were subjected to structured light scanning, CBCT scanning, and intra-oral scanning. Two commercially available software packages were used to perform fusion of the intra-oral scans in the CBCT scan to create an accurate virtual head model: IPS CaseDesigner® and OrthoAnalyzer™. The structured light scanner was used as a gold standard and was superimposed on the virtual head models, created by IPS CaseDesigner® and OrthoAnalyzer™, using an Iterative Closest Point algorithm. Differences between the positions of the intra-oral scans obtained with the software packages were recorded and expressed in six degrees of freedom as well as the inter- and intra-observer intra-class correlation coefficient.ResultsThe tested software packages, IPS CaseDesigner® and OrthoAnalyzer™, showed a high level of accuracy compared to the gold standard. The accuracy was calculated for all six degrees of freedom. It was noticeable that the accuracy in the cranial/caudal direction was the lowest for IPS CaseDesigner® and OrthoAnalyzer™ in both the maxilla and mandible. The inter- and intra-observer intra-class correlation coefficient showed a high level of agreement between the observers.Clinical relevanceIPS CaseDesigner® and OrthoAnalyzer™ are reliable software packages providing an accurate fusion of the intra-oral scan in the CBCT. Both software packages can be used as an accurate fusion tool of the intra-oral scan in the CBCT which provides an accurate basis for 3D virtual planning.