Sex estimation of frontal sinus volume from computed tomography scans in a Western Australian adult population.

With the increasing use of radiological three-dimensional imaging, different metric and morphological aspects of the frontal sinuses (FS) have been examined relative to their potential to aid human identification, including sex estimation. The aim of this study is to assess the validity of the metric analysis of the FS volume for estimating sex in a Western Australian (WA) adult population, following the Michel et al. (2015) method. The right, left and total frontal sinus volume (TFSV) from 99 computed tomography scans (47 males and 52 females) of WA individuals aged 18-40 years were three-dimensionally reconstructed using OsiriX® and their volumes acquired in mm3. Sexual dimorphism in the TFSV was tested, and the accuracy of the Michel et al. (2015) formulae was calculated. Population-specific regression equations were also produced. There was a significant difference between the mean TFSV in males and females. The classification accuracy derived from the Michel et al. (2015) formulae was 59.6%. The WA-specific logistic regression analysis yielded an accuracy of 57.2%. The low accuracy rates preclude the use of the sex estimation method in the WA population, but the volume analysis confirmed the individual variability of the frontal sinuses, which may be useful for personal identification.

Growth and microanatomy of the paranasal sinuses in two species of New World monkeys.

Paranasal sinuses of living apes and humans grow with positive allometry, suggesting a novel mechanism for bone enlargement. Here, we examine the paranasal sinuses of the owl monkey (Aotus spp.) and a tamarin (Saguinus midas) across postnatal development. The prediction that paranasal sinuses grow disproportionately faster than the main nasal chamber is tested. We used diffusible iodine-based contrast-enhanced computed tomography and histology to study sinuses in eight Aotus and three tamarins ranging from newborn to adult ages. Sinuses were segmented at the mucosa-air cavity interface and measured in volume. All sinuses were lined by a ciliated respiratory epithelium, except for the ethmoid air cells in Aotus, which are lined in part by olfactory epithelium. An age comparison indicates that only the maxillary sinus and ethmoid air cells are present in newborns, and two additional sinuses (invading the orbitosphenoid and the frontal bone), do not appear until late infancy or later. Comparing newborns and adults, the main nasal airway is 10 times larger in the adult Aotus and ~ 6.5 times larger in adult Saguinus. In contrast, the maxillary sinus far exceeds this magnitude of difference: 24 times larger in the adult Aotus and 46 times larger in adult Saguinus. The frontal sinuses add significantly to total paranasal space volume in both species, but this growth is likely delayed until juvenile age. Results suggest ethmoid air cells expand the least. These results support our prediction that most paranasal sinuses have a distinctly higher growth rate compared to the main nasal chamber.

Change of frontal sinus in age of according to the international frontal sinus anatomy classification.

BACKGROUND: The radiological and surgical anatomy of the frontal sinus should be well-known in all age groups to successfully manage frontal sinus diseases and reduce the risk of complications in sinus surgery. PURPOSE: To define frontal sinus and frontal cells according to the International Frontal Sinus Anatomy Classification (IFAC) criteria in pediatrics and adults. MATERIAL AND METHODS: A total of 320 frontal recess regions of 160 individuals (80 pediatric, 80 adults) who underwent a computed tomography (CT) scan of the paranasal sinus (PNS) were included in the study. Agger nasi cells, supra agger cells, supra agger frontal cells, suprabullar cells, suprabullar frontal cells, supraorbital ethmoid cells, and frontal septal cells were evaluated in the CT analysis. RESULTS: The incidence rates of the investigated cells were determined to be 93.1%, 41.9%, 60.0%, 76.3%, 58.5%, 18.8%, and 0% in the pediatric group, respectively, and 86.3%, 35.0%, 44.4%, 54.4%, 46.9%, 19.4%, and 3.4% in the adult group, respectively. Considering the unilateral and bilateral incidence of the cells, agger nasi cells were highly observed bilaterally in both the pediatric group (89.87%) and the adult group (86.48%). CONCLUSION: Our study results show that IFAC can be used as a guide to increase the chance of surgical treatment in the pediatric and adult groups and that the prevalence of frontal cells can be determined radiologically and contributes to the generation of estimations of the prevalence of frontal cells.

The dimensional and morphological assessment of the frontal sinus in sex estimation among different populations.

BACKGROUND: The purpose of the present study was to determine the dimorphic potential of the frontal sinus (FS) index, area, and the combination of both variables to ascertain its accuracy in sex discrimination among Bosnian, Chinese, and Nepalese. METHODS: A retrospective study analyzed the digital standardized lateral cephalometric of 654 Bosnian, Chinese, and Nepalese adult patients (116 females, 102 males; age range 17-40 years). The following FS parameters were analyzed: The maximum height, width, and area of the FS, and the ratio of height and width was calculated as the FS index. The measurements were analyzed using logistic regression analysis for the FS index, area, and combined FS index and area. RESULTS: Statistically significant differences were observed between the mean values of the FS index and the area between females and males in each population. The highest frequency of bilateral absence of FS was detected among females, specifically in Chinese (6.6%). Logistic regression equation derived from the present study differentiated between sexes with higher classification percentages for the FS index and area with 62.4%, 75.2%, and 78.4% among Bosnian, Chinese, and Nepalese subjects, respectively. CONCLUSIONS: The results of the present study highlight the implications of the combined FS index and area as a reliable approach in sex estimation in forensic science whenever both the FS structure and lateral cephalometric are available.

Computed tomography analysis of the anterior ethmoid genu of the frontal recess in non-diseased sinuses.

OBJECTIVE: Knowledge of anatomical variations of the frontal recess and frontal sinus and recognition of endoscopic landmarks are vital for safe and effective endoscopic sinus surgery. This study revisited an anatomical landmark in the frontal recess that could serve as a guide to the frontal sinus. METHOD: Prevalence of the anterior ethmoid genu, its morphology and its relationship with the frontal sinus drainage pathway was assessed. Computed tomography scans with multiplanar reconstruction were used to study non-diseased sinonasal complexes. RESULTS: The anterior ethmoidal genu was present in all 102 anatomical sides studied, independent of age, gender and race. Its position was within the frontal sinus drainage pathway, and the drainage pathway was medial to it in 98 of 102 cases. The anterior ethmoidal genu sometimes extended laterally and formed a recess bounded by the lamina papyracea laterally, by the uncinate process anteriorly and by the bulla ethmoidalis posteriorly. Distance of the anterior ethmoidal genu to frontal ostia can be determined by the height of the posterior wall of the agger nasi cell rather than its volume or other dimensions. CONCLUSION: This study confirmed that the anterior ethmoidal genu is a constant anatomical structure positioned within frontal sinus drainage pathway. The description of anterior ethmoidal genu found in this study explained the anatomical connection between the agger nasi cell, uncinate process and bulla ethmoidalis and its structural organisation.

Anterior ethmoid and frontal sinus drainage pathways: five patterns formed and defined by their bony walls.

PURPOSE: To perform endoscopic sinus surgery safely and effectively, surgeons need to visualize the complex anatomy of the anterior ethmoid and frontal sinus region. Because this anatomy is so variable and individualized, the foundation of understanding lies in identifying, following, and visualizing the drainage pathway patterns and anticipating possible variations. METHODS: We studied 100 sides (50 cases: 22 male, 28 female, aged 12-86, average age 46.5 years, ± 19.5) using computed tomography (CT) and multiplanar reconstruction (MPR) to identify and classify the drainage pathways leading to the frontal sinus and anterior ethmoidal cells. RESULTS: Analysis revealed five patterns of drainage pathways defined by their bony walls: between the uncinate process and the lamina papyracea [UP-LP]; between the uncinate process and the middle turbinate [UP-MT]; between the uncinate process and the accessory uncinate process [UP-UPa]; between the uncinate process and the basal lamella of the ethmoidal bulla [UP-BLEB]; and between the basal lamella of the ethmoidal bulla and the basal lamella of the middle turbinate [BLEB-BLMT]. In most cases, BLEB formed the posterior wall of the drainage pathway of the frontal sinus, indicating BLEB could be one of the most important landmarks for approaching the frontal sinus. CONCLUSIONS: As endoscopic sinus surgery depends on an understanding of this anatomy, this study may help surgeons to identify and follow the drainage pathways more accurately and safely through the anterior ethmoid to the frontal sinus.

The dimensional and morphological assessment of frontal air sinus in different ages, genders and ethnicities (Arabian-Caucasian and Han-Chinese sub-populations).

OBJECTIVE: This study aimed to assess the dimensional and morphological measurements of the frontal air sinuses in different ages and genders in the two ethnicities. MATERIALS AND METHODS: This retrospective study included 360 subjects (160 males and 200 females) of both ethnicities. Subjects were divided based on age and gender into four groups, including an equal number of both males and females, for each age and ethnic group. The frontal air sinus dimensions were measured utilizing lateral cephalometric radiographs and computed using Winceph version 9.0 software. The frontal air sinus dimensions were compared between age groups in both genders and between ethnicity using an independent sample t test. The relationship between the frontal air sinus dimensions and subjects' age was evaluated using Pearson's correlation coefficient. RESULT: The frontal air sinuses measurements were larger in males than females in both ethnicities, except for the frontal sinus index, which was found to be larger in females than males. The frontal air sinus surface area and height showed statistically significant differences between the two age groups in both ethnicities (P < 0.05). The Arabian-Caucasian patients had a larger frontal sinus surface area, height, and depth than the Han-Chinese patients in both age groups. CONCLUSION: The size of the frontal air sinus increases with age; and continues to expand after the age of 20 years. Based on the Arabian-Caucasian and Han-Chinese sub-population findings, the frontal sinus is an effective tool for determining gender and appears to have potential in ethnicity identification.

Anatomic misconceptions regarding the agger nasi cell: A preliminary analysis utilizing endoscopic anatomic dissection and three-dimensional computed tomography.

The agger nasi cell is a key anatomic landmark in endoscopic frontal sinus surgery. However, discord amongst authors regarding anatomic definition and prevalence raises questions of its suitability as a surgical landmark. The purpose of this investigation is to evaluate the agger nasi cell using radiographic imaging correlated with endoscopic anatomic dissection to consider the cell's role as a surgical landmark and to explore if three-dimensional computed tomography (3D-CT) technology can provide enhanced insight into this anatomy. CT scans of 11 cadaveric sinonasal complexes were studied using triplanar CT or 3D-CT scanning with stereoscopic 3D imaging. Endoscopic dissections were performed and video recorded. Attention was given to identify agger nasi pneumatization and its origin. Pneumatization of the agger nasi region was noted in 4/11 cases (36.4%) (in two cases the pneumatization arose from the frontal recess, in two from a true agger nasi cell). The agger nasi region appeared as solid unpneumatized bone in 4/11 cases (36.4%). In 3/11 cases (27.3%) limited pneumatization was noted, bordering on but not pneumatizing the agger nasi proper. It may be confusing for otolaryngologic surgeons in training to rely on the "agger nasi cell" as a surgical landmark due to misconceptions regarding the anatomy, prevalence and anatomic definitions. Using standard CT scans to teach anatomy may have shortcomings as compared to the gold standard of surgical dissection. However, new 3D-CT holds promise to more accurately reflect small microanatomic features and provide an improved road map of a patient's anatomy in surgery.

Volumetric Assessment of the Frontal Sinus in Female Adolescents and Its Relationship with Craniofacial Morphology and Orthodontic Treatment: A Pilot Study.

The present study aimed to evaluate the correlation between frontal sinus morphology and craniofacial morphology, and to investigate the effects of orthodontic treatment on the development of the frontal sinus in female adolescents (mean age: 13.9 ± 1.3 years). In total, 53 patients were recruited and underwent cephalography and computed tomography before and after orthodontic treatment. Of these patients, most had a bilaterally symmetrical fan-shaped frontal sinus without any fusion. The average size and volume of the frontal sinus before orthodontic treatment were 45.8 ± 12.3 mm in breadth, 29.8 ± 7.3 mm in height, 22.7 ± 5.1 mm in depth, and 5151.6 ± 2711.4 mm2 in volume. Sinus volume in patients with skeletal Class III malocclusion tended to be larger than that in patients with skeletal Class I and II malocclusion. Upon comparison with the pretreatment measurements, the sizes and volumes of the frontal sinus were significantly larger following orthodontic treatment, regardless of the skeletal pattern; however, since these changes were small, the increases in the size and volume of the frontal sinus may have been caused by pubertal growth and not orthodontic treatment. The clinical relevance of the frontal sinus remains controversial.

Nasal Spine of the Frontal Bone: A Consistent Landmark for Safe Outside-In Frontal Drill-Out.

BACKGROUND: Outside-in frontal drill out entails drilling the frontal sinus floor in the midline before identifying and dissecting the frontal recesses. It is a more direct approach, especially in revision surgery or cases with challenging anatomy. OBJECTIVES: The aim of this study was to highlight the anatomical and surgical concepts for easy and safe outside-in frontal drill out by a preclinical anatomic study on cadaveric heads. In addition, to review our experience with this approach over a 5-year period for challenging frontal sinus pathologies. METHODS: The study included 2 sectors; a preclinical study, in which 5 cadaveric heads were dissected and studied to identify and standardize the anatomical landmarks of this approach. This was followed by a clinical case series which included 22 patients with challenging frontal sinus pathologies that were treated with this proposed approach. RESULTS: We concluded from the anatomic study that the nasal spine of the frontal bone (NSFB) and its anatomical orientation in relation to the nasal branch of the anterior ethmoidal artery (NBAEA) is a consistent landmark that enables the surgeon to identify the correct coronal trajectory of drilling to avoid injury of the cribriform and the skull base. The clinical case series included 22 patients that were successfully treated with the proposed approach. No intraoperative nor postoperative complications were reported in this study. Long-term follow-up showed that the frontal neo-ostium was patent in all cases (n = 22). CONCLUSION: Outside-in frontal drill-out is a safe and easy approach; especially in challenging frontal sinus pathologies; using the NSFB and its anatomical coronal orientation to the NBAEA as a consistent landmark, anterior to the skull base. This approach offers early, safe, and direct bone removal without the need for initial identification and dissection of the frontal recess.

Ontogenetic patterns in human frontal sinus shape: A longitudinal study using elliptical Fourier analysis.

Frontal sinus morphology is highly variable across individuals, but little is known regarding how or at what age that variation is reached. Existing ontogenetic studies are conflicting and often cross-sectional in nature, limiting understanding of individualistic growth. Studies investigating sinus growth with longitudinal series often focus on lateral cephalograms and consequently do not capture the sinus morphological features that are most relevant to clinical and medicolegal settings (e.g., arcade/scalloping, width-to-height dimensions, asymmetry). Longitudinal analysis of sinus morphology from frontal radiographs is important to understand when sinus morphology stabilizes. The purpose of this study was to investigate at what age the frontal sinus attains its final shape, and whether sex-based differences in ontogeny are evident, using a longitudinal sample of posterior-anterior (PA) frontal radiographs from the AAOF Legacy Collection. Frontal sinus outlines were manually traced in 935 radiographs from 111 individuals (55F/56M) spanning 8-29 years of age. Outlines were subjected to elliptical Fourier analysis (EFA) and underwent principal components analysis (PCA). PC1 (51.02% of variation) appears to represent the relative height and breadth of the sinus, PC2 (11.73%) and PC3 (10.03%) captures the degree of relative complexity in the outlines. Individual PC scores were plotted against age-in-months with individual Loess growth curves. Overall, younger individuals typically display relatively shorter, flatter sinuses, increasing in vertical complexity with age. Mixed-effect models on PC1 indicate significant effects for the repeated measure of years (p < 0.001). Within individuals, Euclidean distances of PCs between each sinus outline and their oldest-age outline (i.e., final morphology) were calculated and plotted against age-in-months with Loess growth curves. The results indicate that final frontal sinus morphology is mostly attained by 20 yoa regardless of sex. There is sexual dimorphism in ontogenetic trajectories: females attain frontal sinus shape earlier than males. Specifically, Loess growth curves of the Euclidean distances to final sinus shape indicate that female shape shows decreased development at 14-16 yoa, with males approaching stabilization at 18-20 yoa. These trends were supported by paired t-tests on PC1 between each year and the oldest age, whereby significant differences end for females starting at 15 and 18 yoa for males. The timing of shape-stabilization in the current study closely aligns with previous studies on linear and size dimensions, indicating a close relationship between the ontogeny of frontal sinus shape and size. This research has several implications in diverse fields. Documenting ontogenetic patterns in modern humans could lead to more accurate interpretations of frontal sinus variation in hominin lineages. Understanding the age at which frontal sinus shape and size stabilizes in pediatric populations has important clinical implications, with future studies needed to investigate if/how sinus development directly relates to sinonasal disease susceptibility (e.g., sinusitis), surgical complications, and/or expected trauma patterns. For forensic practitioners utilizing frontal sinus comparisons for decedent identifications, it is important to know at what age these features stabilize to understand how much change may be expected between antemortem and postmortem radiographs.

Morphological and dimensional variations of the frontal air sinuses in a group of adolescent Caucasians and Chinese in different skeletal malocclusions: a cross-sectional cephalometric study.

OBJECTIVE: This study aimed to evaluate the morphological and dimensional variations of the frontal air sinuses in a group of adolescent Caucasians and Chinese with different skeletal malocclusions in both genders. MATERIALS AND METHODS: This retrospective study included 290 adolescent Caucasians and Chinese patients with 145 each. Each sample included 90 females and 55 males and was categorized based on ANB angle in reference to each population norms into 65 skeletal class I, 50 skeletal class II, and 30 skeletal class III malocclusions. All linear, angular, and surface area measurements of the frontal air sinuses were evaluated using lateral cephalometric radiographs and calculated using Winceph version 8 software. The frontal air sinus parameters were compared between genders and the two ethnic groups using an independent sample t-test. ANOVA with Tukey's post hoc tests were used to compare the frontal air sinus parameters between the three skeletal malocclusions. RESULT: The frontal air sinus width and surface area were found to be significantly greater in Caucasians when compared with Chinese patients. According to gender, the frontal air sinus length, width, and surface area, as well as the glabella convexity, were greater in males than females, while the frontal air sinus index (length/width) was significantly greater in females than males in both ethnic groups. In both ethnic groups, the frontal air sinus surface area was significantly greater in skeletal class III malocclusion when compared to skeletal class I and class II malocclusions in Caucasians (P = 0.0022) and Chinese (P = 0.0097). There was a weak-to-moderate correlation between the frontal air sinus parameters and the nasio, sella, and glabella positions (R = -0.56 to 0.62). CONCLUSION: The frontal air sinus dimensions and surface area varied greatly in between ethnic groups, genders, and malocclusion types. The frontal air sinus parameters were correlated with nasion, sella, and glabella positions. CLINICAL RELEVANCE: These findings could assist orthodontists, ENT specialist, and forensic medical investigators to focus on the size of frontal sinus during treatment planning, the relationship between the size of frontal air sinus and malocclusions, and age determination.

Three-dimensional computed tomography analysis of frontal recess cells according to the International Frontal Sinus Anatomy Classification (IFAC) - difficulties in identification of frontal recess cells in patients with diffuse primary chronic rhinosinusitis?

<br><b>Introduction:</b>The International Frontal Sinus Anatomy Classification (IFAC) is a consensus document created to standardize and specify the naming of cells within the region of the frontal recess and frontal sinus.</br> <br><b>Aim:</b> The aim of this study was to analyze the difficulties in identifying cells according to the IFAC in patients with diffuse primary chronic rhinosinusitis.</br> <br><b>Material and methods:</b> Three independent reviewers examined triplanar computed tomography (CT) scans to assess the anatomy of the frontal recess using the IFAC system. CT scans were chosen randomly and divided into 3 groups: CT scans of patients not presenting sinus complaints (control group), CT scans of patients affected by diffuse primary chronic rhinosinusitis non-type 2, and CT scans of patients affected by diffuse primary chronic rhinosinusitis type 2.</br> <br><b>Results:</b> Identification of all frontal cell types was accurate in patients not presenting sinus complaints (P-value < 0.05). Patients scoring 9 or more points in the Lund-Mackay scoring system demonstrated a statistically increased risk of improper identification of frontal recess cells (P-value < 0.0001).</br> <br><b>Conclusions:</b> Due to a large number of possible anatomical variants and changes caused by the chronic inflammatory disease, the IFAC nomenclatura is easier to apply to non-type 2 primary diffuse CRS patients with low scores in the L-M score scale than to primary diffuse type 2 CRS patients with higher M-L scores.</br>.

Nasosinusal Endoscopic Anatomy and Physiology

The present article focuses on the analysis of the nasal cavity's anatomy succinctly and descriptively. This essay was carried out through a bibliographic review, directed to the detailed anatomy of the nasal cavity, and the structures that form its sinuses. We have identified the need formore studies directed to the related anatomical area so that the improved knowledge of this region ensures a nasoendoscopic treatment with better effectiveness and no complications.

Computed Tomography Analysis of the Anterosuperior Portion of the Bulla Lamella in Chinese Subjects and Its Surgical Significance in Endoscopic Frontal Sinusotomy.

INTRODUCTION: The anterosuperior portion of the bulla lamella can extend into the frontal sinus and form the supra bulla frontal cell (SBFC) and supraorbital ethmoid cell (SOEC). This can affect the frontal drainage pathway and make surgery more challenging. OBJECTIVES: The aim of the study was to compare the anatomical characteristics of SBFC and SOEC in Chinese chronic rhinosinusitis (CRS) patients and explore the relationship between the cells and frontal sinusitis (FS). The surgical skills in dealing with these cells were also studied. METHODS: We prospectively identified SBFC and SOEC in 114 patients with CRS by computed tomography (CT). The sides of the patients were divided into groups A (with FS) and B (without FS). CT scans were analyzed to distinguish the SBFC, SOEC, and the drainage pathway. Statistical analysis was conducted to determine whether the cells were associated with the occurrence of FS. RESULTS: The prevalence of frontal cells was as follows: SBFC: 9.65%, SOEC: 21.93%. There was an association between the presence of SBFC and FS (p < 0.05). The anterior drainage pathway was present in patients with SBFC and SOEC, anterolateral pathway in those with SBFC/SOEC coexisting with the frontal septal cell, and anteromedial pathway in those with SBFC/SOEC coexisting with the supra agger frontal cell. CONCLUSIONS: There was an association between the presence of SBFC and the occurrence of FS. Extension of the anterosuperior portion of the bulla lamella into the frontal sinus obstructed the drainage pathway posteriorly. Understanding the anatomy may help surgeons thoroughly dissect the bulla lamella.

Computer-aided superimposition of the frontal sinus via 3D reconstruction for comparative forensic identification.

The anatomical uniqueness of the frontal sinus morphology has been widely used for comparative forensic identification using various techniques, mostly including 2D X-rays or one fixed slice of an axial computed tomography (CT) scan image. However, computer-aided 3D automatic graphical comparison techniques can provide accurate comparisons between two 3D models that allow users to comply with even the strictest deviation standards, avoiding error-prone identification of frontal sinuses with similar morphologies. The study proposes the use of a computer-aided comparative paradigm based on the 3D-3D frontal sinus model superimposition process and further assesses the anatomical uniqueness of frontal sinuses using a large Chinese Han sample. Three hundred thirty-six patients older than 20 years with two multi-slice CT scans were collected. Frontal sinus 3D models were semi-automatically segmented through Dolphin Imaging software. Automatic pairwise comparisons of 336 matched pairs from the same person and 340 mismatched pairs from different individuals with an analysis of average root mean square (RMS) point-to-point distance were performed using Geomagic Studio Qualify software. RMS ranged between 0.005 and 1.032 (mean RMS 0.390 ± 0.25 mm) in the group of matches and between 1.107 and 19.363 (mean RMS 4.49 ± 2.69 mm) in the group of mismatches. On average, the RMS value was over ten-fold greater in mismatches than in matches. Statistically significant differences in RMS between the group of matches and mismatches were assessed using the Mann-Whitney U test (p < 0.05). This study supports the value of the frontal sinus with a 3D computer-aided superimposition method for human identification with large samples when DNA, fingerprints, and dental materials are not accessible.

A stepwise approach to open surgery for the frontal sinus.

BACKGROUND: Despite advances in endoscopic techniques, there are still instances when the frontal sinus must be approached externally. Given its variable anatomy, the frontal sinus continues to present a challenge to the surgeon. Our rule of thumb capitalises on the consistent embryological development of the frontal sinus, aiding safe external access. METHODS AND RESULTS: The presented stepwise approach includes trephination, fenestration, an osteoplastic flap and obliteration. The obliteration procedure has produced good results in managing those patients with disabling symptoms despite multiple endoscopic procedures.

Frontal sinus anatomy of the noble Swéerts-Sporck family and verification of their biological relationships using similarity analysis.

The evaluation of frontal sinus similarity is one way to detect biological relationships, especially in small groups, including families of historically known personalities. However, possibilities for studying this issue are currently limited. This contribution deals with the frontal sinuses of a rare osteological sample with known genealogical data, members of the noble Swéerts-Sporck family from the 17th to 20th centuries. The aim is to verify whether the frontal sinuses reflect documented family relationships. Basic dimensions of the frontal sinus such as total surface area and volume, and maximum height and width, and also morphology and anatomical features were evaluated using computed tomography scans. The portions of the frontal sinus above the "external supraorbital line" were analyzed. The degree of similarity between biologically related individuals was determined for each variable and compared with their known biological distance. The degree of similarity based on dimensions was evaluated using both the unadjusted measured data and standardized data adjusted to size. For the unadjusted dimensions, a positive correlation between morphological similarity and biological relatedness was apparent. On the other hand, no positive correlation was apparent for most of the standardized data. Only total volume showed a very weak indication of a positive trend in the standardized data, but this was weaker than in the original values. A positive quantifiable relationship between morphological patterns and biological distance is not clearly indicated. However, nonmetric features do support the documented relationships of the individuals.

Morphological analysis of three-dimensionally reconstructed frontal sinuses from Chinese Han population using computed tomography.

The uniqueness and reliability of frontal sinuses for personal identification have gained wide recognition in forensics. However, few studies have assessed the usefulness of a three-dimensional (3D) model of the frontal sinus for human identification. This study aimed to develop standardized techniques to classify the frontal sinus according to its 3D morphological metrics and discover the usefulness of the 3D frontal sinus model in identification of Chinese Han population. One hundred and ninety-six computed tomography (CT) scans of patients older than 20 years (84 males and 112 females) were collected. A 3D frontal sinus digital model was segmented using Dolphin Imaging software. The following morphological metrics of the 3D frontal sinus were used to develop the coding system: bilateral or unilateral, spatial relationships of the two sides, number of septations, superior volume side, the shape of the 3D model of each side, shape of the medial surface and frontal ostium on each side, number of accessory septations on each side, number of supra-orbital cells of the medial surface and lateral surface on each side, and number of the arcades on each side. The new coding system accurately identified all of our research individuals. This study discovered a number of individual variations in the 3D frontal sinus morphology patterns. A coding system, which is based on these morphological patterns, exposes the morphological variants of frontal sinuses and presents the usefulness of 3D frontal sinus model for human identification.

Frontal sinus: is it a predictor for vertical malocclusions?

The aim of the present study was to evaluate 3D frontal sinus morphology in consideration with different vertical facial developments. The study was conducted with the pre-treatment CBCT images of 87 patients, who were divided into 3 groups according to the sum of the posterior angle. The frontal sinus measurements were performed on the axial, sagittal, and coronal sections of the CBCT images. Craniofacial measurements were performed on the lateral cephalograms, obtained from the CBCT scans. Normal distribution of the data was confirmed by the Kolmogorov-Smirnov test. ANOVA, followed by post hoc Duncan tests, was used to compare the differences among the three groups. The relationships between sinus dimensions and craniofacial parameters were assessed by the Pearson's correlation coefficient (P < 0.05). The maximum anterior-posterior dimension of the frontal sinuses (0.017), the width of the right (0.020) and left (0.041) frontal sinuses, and the anterior-posterior dimension of the left (0.038) frontal sinus were significantly smaller in the hyperdivergent group compared to hypodivergent group. There was no significant difference between groups in terms of the height of the frontal sinuses. Significant correlation was noted between the maximum anterior-posterior dimension of the frontal sinus and SN-PP, N-Me, N-ANS, SN-GoGn, Post. sum, and Jarabak's ratio. No significant correlation between the height of the frontal sinuses and the craniofacial measurements was found. Individuals with vertical growth pattern presented decreased anterior-posterior dimension of the frontal sinuses, revealing significant correlations with vertical craniofacial parameters.