Nasal Airway Volume Research Articles

Three-dimensional assessment of the nasopharyngeal airway in Down syndrome during the mixed dentition period: a case-control study.

In this retrospective case-control study, we aimed to evaluate the nasopharyngeal airway volume of children with Down syndrome (DS) and compare the results with those of control participants well matched for sex and age. Fifteen children with DS (mean age = 9.43 ± 0.38 years; 8 boys, 7 girls) and 15 control participants (mean age = 9.51 ± 0.40 years; 8 boys, 7 girls) were enrolled. The nasopharyngeal airway volume and the cross-sectional morphology were measured with cone-beam computed tomography taken for orthodontic treatment. All measurements were assessed by analysis of covariance (ANCOVA) using Bonferroni post hoc pairwise comparison tests. Covariates were body height and body weight, and the ANB angle and the mandibular plane angle. Significance was set at P < .0019. Nasal airway, superior airway, and total airway volumes of DS participants were significantly smaller than those of the control participants in ANCOVA results adjusted for ANB angle and mandibular plane angle (P = .000). In ANCOVA results adjusted for body height and body weight, no statistically significant differences in the volume measurements were found. The results indicate that the nasopharyngeal airway volume differs between children with and without DS and that the airway volume tends to be smaller in DS children than in children without DS.

Assessment of nasal respiration and three-dimensional airway volume changes in orthognathic surgery patients

ObjectivesThe aim of this study was to evaluate the effect of maxillary movements in orthognathic surgery on nasal airway volume change and its correlation with airflow and resistance. Materials and methodsThis study included 25 patients (8 male, 17 female) with Class II (6 patients) or Class III (19 patients) malocclusion. All patients underwent Le Fort I and bilateral sagittal split ramus osteotomy. Nasal airflow and resistance were measured by using rhinomanometry and acoustic rhinometry pre and six months post-operatively. Nasal volume was measured using computed tomography before surgery and six months after surgery. ResultsNasal volume increased in 10 out of 11 patients with CCW (counterclockwise) rotation and decreased in 1 patient while, nasal volume increased in 5 patients with CW (clockwise) rotation and decreased in 9 patients. Superior nasal airway volume increased significantly, while the effects on nasal flow and resistance were not significant. Additionally, no significant correlation was found between airway volume changes and variations in airflow and resistance. ConclusionCCW rotation in orthognathic surgery patients significantly increased superior nasal airway volume but did not improve nasal airway flow and resistance

Nasal Airway Volumes are More Asymmetric in Skeletally Mature Patients With Cleft lip and Palate Than Controls on 3-Dimensional Analysis.

This study assesses nasal airway volumes in skeletally mature patients with CLP and healthy controls and examines the relationship among nasal volumes, cleft laterality, and facial asymmetry. Computed tomography images from patients with CLP and controls were analyzed using Mimics Version 23.0 (Materialise, Leuven, Belgium). Relationships among nasal airway volume, cleft laterality, and facial asymmetry were compared. The 89 patients in this study included 66 (74%) CLP and 23 (17%) controls. Nasal airway volumes in CLP were more asymmetric than controls (26.8±17.5% vs. 17.2±14.4%; P=0.015). In UCLP, the smaller nasal airway was on the cleft side 81% of the time (P<0.001). Maximum airway stenosis was on the cleft side 79% of the time (P<0.001), and maximum stenosis was on the same side as the smaller airway 89% of the time (P<0.001). There was a mild linear relationship between nasal airway asymmetry and maximum stenosis (r=0.247, P=0.023). On 3-dimensional image reconstruction, the septum often bowed convexly into the cleft-sided nasal airway with a caudal deviation towards the noncleft side. Nasal airway asymmetry was not associated with facial midline asymmetry (P>0.05). The nasal airway is more asymmetric in patients with cleft lip and palate compared with the general population, with the area of maximum stenosis usually occurring on the cleft-sided airway. In patients with unilateral cleft lip and palate, the septum often bows into the cleft side, reducing the size of that nasal airway. Nasal airway asymmetry did not correlate with facial asymmetry.

Evaluation of nasal septal deviation and maxillary bone and nasal airway dimensions and volumes using cone-beam computed tomography in patients with unilateral palatal canine displacement: a retrospective study.

To detect any association between palatally displaced canine (PDC) and nasal septal deviation (NSD), palatal bone thickness and volume, and nasal airway dimensions and volume. A total of 92 patients were included and subdivided into two groups: group 1, unilateral PDCs (44 patients), and group 2, normally erupted canines (NDCs) (48 subjects). The following variables were measured using cone-beam computed tomography: presence and type of NSD, nasal width, inferior conchae, hard palate and nasal septum thickness, maxillary bone and nasal airway volumes. NSD was detected in 77% and 50% of PDC and NDC subjects, respectively. Within the PDC subjects, significant differences between the displaced and nondisplaced sides were detected. Palate thickness was increased in the canine region and reduced in the molar region. Compared with the control group, PDC subjects had reduced palate thickness and lower nasal airway volume. Two predictors were significant for predicting the odds of PDC occurrence: NSD and maxillary bone volume. NSD is more frequent in PDC subjects. PDC subjects have reduced palate thickness and decreased nasal airway volume. In the presence of NSD, the odds of developing PDC increase by 3.35 times, and for each one-unit increase in the maxillary bone volume, the odds of developing PDC decrease by 20%.

Effectiveness of out-fracture of the inferior turbinate with reduction nasal bone fracture.

The nasal bone, being the most protruding bone in the center of the facial bones, is particularly susceptible to damage. Nasal bone fractures can often result in secondary deformation and dysfunction of the nose, including septal fractures. Studies on functional or intra-nasal complications have been rarely reported after nasal bone fracture reduction. To evaluate the severity of nasal obstruction and its improvement following nasal bone fracture reduction using inferior turbinoplasty. We conducted a retrospective review of data from 50 patients with symptomatic nasal obstruction between January to December 2010. All patients underwent preoperative Computed tomography evaluation, and symptom changes and nasal cavity volume were analyzed using a visual analog scale and acoustic rhinometry before and after surgery. Closed reduction and out-fracture of both inferior turbinates performed by the same surgeon. Treatment outcomes were assessed by comparing changes in the nasal airway volume measured using acoustic rhinometry before and after surgery. The minimal cross-sectional area (MCA) was also analyzed based on the Stranc classification. Before reduction, the mean MCA for all cases was 0.59 ± 0.06 cm2, which represented an 11% decrease compared to the average size of a Korean adult (0.65 ± 0.03 cm2). The MCA for frontal impact was 0.60 ± 0.02 cm2 and for lateral impact, it was 0.58 ± 0.03 cm2. After reduction via inferior turbinoplasty, the MCA improved to 0.64 ± 0.04 cm2. This study suggests that turbinoplasty is helpful in addressing nasal obstruction. Out-fracture of the inferior turbinate is an effective and durable technique that can be easily performed to enlarge the nasal airway with minimal morbidity.

Genetic Subtypes of Apert Syndrome Are Associated With Differences in Airway Morphology and Early Upper Airway Obstruction.

Apert syndrome is predominantly caused by 2 paternally inherited gain-of-function mutations in the FGFR2 gene, Pro253Arg, and Ser252Trp. Studies comparing phenotypic features between these 2 mutations have established differences in syndactyly severity and incidence of cleft palate. Obstructive sleep apnea can be debilitating in a subset of patients with Apert syndrome, yet is not well understood. This study aims to determine whether FGFR2 mutations impart differential effects on airway physiology and morphology. Patients with Apert syndrome and confirmatory molecular testing were reviewed for polysomnography, nasal endoscopy, microlaryngoscopy and bronchoscopy, and computed tomography imaging. Obstructive apnea-hypopnea index and oxygen saturation nadir, nasal airway volumes, choanal cross-sectional area, and midfacial cephalometric dimensions were compared across mutation types. Twenty-four patients (13 Ser252Trp, 11 Pro253Arg) were included. Severe obstructive sleep apnea (obstructive apnea-hypopnea index>10) occurred in 8 (62%) patients with Ser252Trp mutations compared with 1 (9%) patient with Pro253Arg mutations ( P =0.009). Computed tomography imaging at 1 year of age demonstrated that nasopharyngeal airway volumes were 5302±1076mm 3 in the Ser252Trp group and 6832±1414mm 3 in the Pro253Arg group ( P =0.041). Maxillary length (anterior nasal spine-posterior nasal spine, P =0.026) and basion-anterior nasal spine ( P =0.007) were shorter in patients with Ser252Trp mutations. The findings suggest that the Ser252Trp mutation in Apert syndrome is associated with higher severity obstructive sleep apnea and decreased nasopharyngeal airway volume. Heightened clinical awareness of these associations may inform treatment planning and family counseling.

New insights into the variability of upper airway morphology in modern humans.

The biological adaptation of the human lineage to its environment is a recurring question in paleoanthropology. Particularly, how eco-geographic factors (e.g., environmental temperature and humidity) have shaped upper airway morphology in hominins have been subject to continuing debate. Nasal shape is the result of many intertwined factors that include, but are not limited to, genetic drift, sexual selection, or adaptation to climate. A quantification of nasal airway (NA) morphological variation in modern human populations is crucial to better understand these multiple factors. In the present research, we study 195 in vivo CT scans of adult individuals collected in five different geographic areas (Chile, France, Cambodia, Russia, and South Africa). After segmentation of the nasal airway, we reconstruct 3D meshes that are analyzed with a landmark-free geometric morphometrics method based on surface deformation. Our results highlight subtle but statistically significant morphological differences between our five samples. The two morphologically closest groups are France and Russia, whose NAs are longer and narrower, with an important protrusion of the supero-anterior part. The Cambodian sample is the most morphologically distinct and clustered sample, with a mean NA that is wider and shorter. On the contrary, the Chilean sample form the most scattered cluster with the greatest intra-population variation. The South African sample is morphologically close to the Cambodian sample, but also partially overlaps the French and Russian variation. Interestingly, we record no correlation between NA volume and geographic groups, which raises the question of climate-related metabolic demands for oxygen consumption. The other factors of variation (sex and age) have no influence on the NA shape in our samples. However, NA volume varies significantly according both to sex and age: it is higher in males than in females and tends to increase with age. In contrast, we observe no effect of temperature or humidity on NA volume. Finally, we highlight the important influence of asymmetries related to nasal septum deviations in NA shape variation.

Changes in inflammatory biomarkers in the nasal mucosal secretion after septoplasty

Deviated nasal septum (DNS) is suggested to be associated with nonspecific inflammation of the nasal mucosa. The authors hypothesized septoplasty may reduce nasal mucosal inflammation, therefore the authors aimed to measure various inflammatory biomarkers in the nasal secretion following septoplasty. Prospectively, 17 patients undergoing elective septoplasty were included. Symptomatic changes after septoplasty were evaluated with Sino-nasal Outcome Test (SNOT-22) and Nasal obstruction symptom evaluation (NOSE) scores. Using acoustic rhinometry, changes of the nasal airway volume were measured. Nasal secretion was collected within 2 weeks and 3 months before and after septoplasty, respectively. The inflammatory biomarker high-mobility group box 1 (HMGB1) and vasoactive intestinal peptide (VIP), and inflammatory cytokines including tumor necrosis factor α (TNF α), interferon γ (IFN-γ), interleukin-4 (IL-4), eotaxin-1, and regulated upon activation, normal T cell expressed and presumably secreted (RANTES) were quantified in the nasal secretion by enzyme-linked immunosorbent assays or multiplex bead array assays. The patients' mean age was 30.5 ± 6.8 (ranging from 19 to 43), consisting of 15 male and 2 female patients. The median SNOT-22 and NOSE scores changed from 54 to 14 and 78 to 15, respectively, both showing a significant decrease. In acoustic rhinometry, nasal cavity volume of convex side significantly increased after septoplasty, whereas significant discrepancy of nasal airway volume between concave and convex sides became insignificant. No significant difference was noted both before and after septoplasty between the concave and convex sides in all seven biomarkers. The HMGB1, RANTES, IL-4, and TNF-α concentrations following septoplasty showed significant decrease in 34 nasal cavities of 17 patients (all p < 0.05). However, when the 17 concave and 17 convex sides were analyzed separately, the significant reduction in four biomarkers were only significant in the concave sides (all p < 0.05), but not significantly reduced in convex sides. Septoplasty may have benefited not only in normalizing the nasal airflow and symptom improvement, but also in nonspecific inflammation attenuation in the nasal airway.

Is maxillary expansion effective in treatment of obstructive sleep apnoea syndrome? A systematic review of systematic reviews.

Background Maxillary expansion (ME) might be beneficial in improving airway dimensions and obstructive sleep apnoea syndrome (OSAS) in patients with constricted maxillae. The aim of this overview is to present clinicians with a summary of the evidence. Data from systematic reviews and meta-analyses were evaluated to investigate the effect of ME on OSAS.Methods An electronic search was commenced in five databases, in addition to a manual search until July 2021. Screening of articles started with title and abstract followed by full-text assessment. Systematic reviews with/without meta-analyses were included. Critical appraisal was done using A Measurement Tool to Assess Systematic Reviews (AMSTAR) 2, Level of Research Design scoring and criteria of body of evidence scores. The search, study selection and critical appraisal were completed by three reviewers.Results In total, 14 systematic reviews with/without meta-analyses were included. The quality of available evidence ranged between low to high, based on the overall quality evaluation.Conclusions Based on the available evidence, maxillary expansion might be able to improve the nasal airway volume and OSAS in both growing and adult patients in the short term. ME can be considered as one of the treatment options in cases with OSAS.

Clinical and 3-dimensional radiographic assessment of nasal airway volume in adult orthodontic patients following mini-screw assisted rapid maxillary expansion: A prospective clinical study

Clinical and 3-dimensional radiographic assessment of nasal airway volume in adult orthodontic patients following mini-screw assisted rapid maxillary expansion: A prospective clinical study

Evaluating the changes in nasal airway volume and nasal airflow after surgically assisted rapid maxillary expansion

This study aims to compare the changes in the nasal airway volume and nasal airflow using acoustic rhinometry (AR), rhinomanometry (RMN), and dental volumetric tomography (DVT) after surgically assisted rapid maxillary expansion (SARME). Our study consists of 13 adults, 3 male and 10 female patients, aged between 15 and 26, with completed skeletal development. In our study, DVT imaging was obtained twice, preoperation and 3 months after expansion. AR and RMN measurements were recorded, and Visual Analog Score (VAS) and Nasal Obstruction Symptom Evaluation (NOSE)Scale surveys were scored at preoperation and 3 months after expansion. Nasopharyngeal-oropharyngeal airway volume and areas were calculated using the Romexis 3.8.3.R (Planmeca,Helsinki, Finland) and Nemotec V2019 (Madrid, Spain) software programs. IBM SPSS Statistics 22 (SPSS IBM, Armonk, New York) was used for statistical analysis. Comparing the preoperation and postexpansion measurements by both software programs revealed a statistically significant increase in the nasopharyngeal airway volume. No statistically significant change was observed in the oropharyngeal airway volume. Furthermore, we found a statistically significant increase in VAS but a significant decrease in NOSE. According to our findings, nasal airway volume increased after SARME, and although there was no significant change in nasal resistance, patients' quality of life increased significantly.

Changes in the nasal and pharyngeal airway volume with miniscrew-assisted rapid palatal expansion appliances

Objectives: The purpose of this study was to assess the volumetric changes in the nasal and pharyngeal airway volume in patients with maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion (MARPE) appliances. Material and Methods: The pre- and post-treatment cone-beam computed tomography scans of 20 subjects who underwent treatment with the MARPE appliance as part of their orthodontic treatment were included in the study. Pre- and post-expansion airway volume measurements of the nasal cavity, nasopharynx, and oropharynx were measured. Linear measurements of the skeletal structures surrounding the nasal cavity were taken to assess the pattern of airway expansion. Paired t-tests were used to evaluate nasal and pharyngeal airway volume changes with expansion. Pearson correlation test was utilized to assess the relationship between nasal and pharyngeal volume changes. Results: A total of 17 out of 20 samples had a successful split of the mid-palatal sutures. A significant increase in nasal airway volume (12.0%) was found post-expansion. In addition, a significant increase in linear measurements of the nasal cavity base width in the frontal plane (7.1%) and both the anterior and posterior widths in the transverse dimension (9.4% and 3.4%, respectively) were found. Significant positive correlations were found between airway volumes and increase in width of the maxillary expansion appliance. Conclusion: The effects of maxillary expansion with a MARPE appliance include an increase in nasal cavity volume, but not the nasopharyngeal and the oropharyngeal airway volume. The nasal cavity expands in a triangular pattern in both the frontal and transverse dimensions following orthopedic expansion with the MARPE appliance. Increase in airway volume is a result of the increase in width of the maxillary expansion appliance.

QS1: Nasopharyngeal Airway and Subcranial Space Analysis in Pfeiffer Syndrome

Background:Tracheotomy in infancy helps patients with Pfeiffer syndrome survive by preventing respiratory crisis, however, difficulty in decannulation consequently may be a challenge. This study attempts to investigate the regional abnormalities of the nasopharyngeal airway in Pfeiffer syndrome, to provide an anatomic basis for the upper airway surgical treatment and decannulation.Method:Seventy-two preoperative CT scans (Pfeiffer syndrome, n=30; control, n=42) were included in this study. The airway volume, cross-sectional area, and cephalometrics, were measured using Materialise software.Results:Patients with Pfeiffer syndrome developed a 50% (p<0.001) reduction of nasal airway volume, and a 44% (p=0.003) restriction in pharyngeal airway volume. The cross-sectional area of Pfeiffer patients at the choana, was only half that of normals’ (p<0.001). The posterior width of nasal airway in Pfeiffer syndrome was shortened by 13% (p=0.003), and the height was reduced by 21% (p<0.001). The cross-sectional areas at condylion and gonion levels, indicating the caliber of pharyngeal airway at entrance and midsection, were reduced by 67% (p<0.001) and 47% (p<0.001), respectively, when compared with normals.Conclusion:Nasal airway volume in Pfeiffer syndrome is significantly restricted, in length, height and width, along with the choanal stenosis in all cases in this cohort. The reduced anteroposterior length of nasal airway contributes to the shortened maxilla, more than the anteroposterior position. The limited nasal pathway height and width results from the hypoplastic sphenoid. Mediolateral and anteroposterior restricted dimensions are evident across the entire course of pharyngeal airway. Therefore, mediolateral maxillary expansion likely benefits Pfeiffer syndrome patients, in addition to maxillomandibular advancement.

Airway Growth in Preoperative Patients with Crouzon Syndrome.

Background: Obstructive sleep apnea is common in patients with Crouzon syndrome, yet it may be caused by multiple factors. This study aims to investigate the natural history of airway development in preoperative Crouzon patients, from infants to adults. Methods: Preoperative computed tomography (CT) scans (Crouzon syndrome, n = 73; control, n = 87) were divided into five age subgroups. CT scans were measured using Materialise software. Results: Before 6 months of age, nasal airway volume in patients with Crouzon syndrome was smaller than normal by 37% (p = 0.002), and the cross-sectional area at the choana reduced by 45% (p < 0.001). The reduction of nasal airway volume and cross-sectional area reached their nadir at 2 years of age, with shortening of 44% and 63% (both p < 0.001), respectively. They gradually caught up to normal dimensions after 6 years of age. Between 2 and 6 years, the pharyngeal airway in patients with Crouzon syndrome reduced 44% (p = 0.011) compared with controls. However, the airway cross-sectional area at condylion and gonion levels was less than normal, before 6 months (35%, p = 0.024) and (44%, p = 0.006) after 2 years of age, respectively. This reduction remains into adulthood. Conclusion: Nasal airway volume is more limited in children with Crouzon syndrome who are younger than 2 years of age. Whereas after 2 years of age, the pharyngeal airway develops significant volume restriction, leading to timing and specific treatment area foci based on the site of temporal maximal constriction.

Growth patterns of the airway in Crouzon syndrome patients with different types of cranial vault suture synostosis

The severity of obstructive respiratory difficulty varies among affected Crouzon syndrome patients. The aim of this study was to investigate the correlation between the restricted airway volume in Crouzon syndrome and the associated type of cranial vault suture synostosis. Computed tomography scans of 68 unoperated Crouzon syndrome patients and 89 control subjects were subgrouped into four types: type I, bilateral coronal synostosis; type II, sagittal synostosis; type III, pansynostosis; type IV, perpendicular combinations of synostoses. Measurements were made using Mimics software. Of type I Crouzon patients, 42% had a restricted nasal airway (P=0.002), while the pharyngeal airway volume was not significantly reduced. Type II Crouzon patients grew normal segmental airway volumes. Crouzon patients of type III developed simultaneously reduced nasal and pharyngeal airway volumes in infancy, by 38% (P=0.034) and 51% (P=0.014), respectively. However, the nasal airway achieved a normal volume by 2 years of age without any intervention, while the pharyngeal airway remained significantly reduced up to 6 years of age, by 42% (P=0.013), compared to controls. Type IV Crouzon patients developed a reduced nasal airway volume (32%, P=0.048) and a non-significant restricted pharyngeal airway (18%, P=0.325). Airway compromise in Crouzon syndrome is variable when associated with different craniosynostosis fusion patterns. Type II (sagittal synostosis) Crouzon patients grew a normal nasopharyngeal airway volume. Those with types I (bicoronal synostosis) and IV (perpendicular synostoses) had significantly restricted nasal airways and a tendency towards a reduced pharyngeal volume. Type III (pansynostosis) Crouzon infants had the worst restriction of both airways, although there was some improvement with age.

Nasopharyngeal airway and subcranial space analysis in Pfeiffer syndrome

Tracheotomy in infancy helps patients with Pfeiffer syndrome to survive by preventing respiratory crisis, but difficulty in decannulation may consequently be a challenge. This study has investigated the regional abnormalities of the nasopharyngeal airway in children with Pfeiffer syndrome to provide an anatomical basis for the surgical treatment and decannulation of the upper airway. Seventy-two preoperative computed tomograms (CT) (Pfeiffer syndrome n=30; control n=42) were included. The airway volume, cross-sectional area, and cephalometrics were measured using Materialise software. Patients with Pfeiffer syndrome developed a 50% (p<0.001) reduction of nasal airway volume, and a 44% (p=0.003) restriction in pharyngeal airway volume. In patients with Pfeiffer syndrome the cross-sectional area at the choana was only half that of the controls (p<0.001). The posterior width of the nasal airway in patients with Pfeiffer syndrome was shortened by 13% (p=0.003), and the height reduced by 21% (p<0.001). The cross-sectional areas at the condylion and gonion levels, which indicate the calibre of the pharyngeal airway at the entrance and midsection, were reduced by 67% (p<0.001) and 47% (p<0.001), respectively, when compared with the controls. The volume of the nasal airway in patients with Pfeiffer syndrome was significantly restricted in length, height, and width, and by choanal stenosis in all cases in this cohort. The reduced anteroposterior length of the nasal airway contributed to the shortened maxilla more than the anteroposterior position. The limited height and width of the nasal pathway was the result of a hypoplastic sphenoid. Restricted mediolateral and anteroposterior dimensions were evident across the entire course of the pharyngeal airway. Mediolateral maxillary expansion in addition to maxillomandibular advancement is therefore likely to benefit these patients.

Novel 3D segmentation for reliable volumetric assessment of the nasal airway: a CBCT study.

Nasal airway obstruction affects up to one-third of Americans and is one of the most common complaints by patients to otolaryngologists. Nasal airway obstruction and obstructive sleep apnea syndrome (OSAS) are closely related. The aim of this study was to use the 3D imaging software, ITK-SNAP as a platform to define a gold standard for anatomically accurate boundaries of the nasal airway in 3D CBCT and to create a more reliable and precise 3D CBCT segmentation of the nasal airway for assisting diagnosis, treatment, and monitoring of nasal airway obstruction and OSAS. After review of the literature to identify established parameters using CBCT and CT technology for the segmentation of the nasal airway, and the existing drawbacks, a gold standard for locating the anatomical boundaries of the nasal airway using CBCT is proposed. This new method aims at standardization of segmentation and quantification, allowing for more reliable comparison between studies. ITK-SNAP software was used to segment three CBCT samples of healthy patients aged 21 to 59 years, who were patients of record, with CBCT obtained for either orthodontic, endodontic, or prosthodontic treatment planning purposes. <br />Results: The literature search identified 11 studies describing nasal airway parameters utilizing CBCT and CT. A great variation was detected on where the anatomical boundaries for the nasal airway were selected. A new standard in the identification of anatomical boundaries of the nasal airway is proposed for consistent segmentation and quantification using 3D CBCT by using the following landmarks: the inferior ANS-PNS border, the anterior nares border, the posterior sella-PNS border, and superiorly the border in alignment with the base of the skull (excluding the ostia, frontal, ethmoidal, and sphenoidal air cells). The three segmented samples were volumetrically measured, and statistically analyzed. The mean average Hounsfield unit intensity using the CBCT samples in this study was 629 with a standard deviation of 190. <br />Conclusion: The literature indicates a lack of a gold standard using CBCT technology for the segmentation of the nasal airway. With the proposed standard in this study, it is possible to quantify the nasal airway volume and thereby its reduction. For the general dental practitioner, this is an important aspect during the evaluation of overall airway assessment. This information can be useful in the diagnosis and treatment of airway compromised dental patients. (Quintessence Int 2021;52:154-164; doi:10.3290/j.qi.a45429).

Airway Development Relevant to Cranial Vault Suture Synostosis Subtype in Apert Syndrome

Introduction: Based on an established classification system of Apert syndrome subtypes, we aim to directly analyze the correlation between segmented airway volume changes and different skull suture synostosis, so as to provide individualized surgical planning for each subgroup of Apert patients. Methods: CT scans of 44 unoperated Apert syndrome and 53 controls were included and subgrouped as: type I. Bilateral coronal synostosis; type II. Pansynostosis; type III. Perpendicular combinations of cranial vault synostosis. CT scans were measured using Mimics and 3-matics software. Results: Type I developed a 41% ( P = .116) reduction in the nasal cavity, yet a normal sized pharyngeal airway. The reduced nasal airway was linked to the decreased cross sectional area ( r = 0.598, P = .001), vertical dimension ( r = 0.719, P &lt; .001), and narrower width ( r = 0.727, P &lt; .001). Type II developed proportionally reduced nasal airway and pharyngeal airway volumes (both 47%, P = .113 and P = .041), along with the proportionally restricted cross sectional areas at choana and condylion levels by 62 to 65%. This reduction is related to the cranial base length ( r = 0.712, P = .048), and also cranial base angulation ( r = 0.780, P = .023). Nasal and pharyngeal airway developed normal volume in type III. However, the cross sectional areas at the gonion level diminished by 74% ( P &lt; .001). Conclusion: Airway development is influenced by subtype of Apert suture synostosis. Type II pansynostosis Apert patients developed synchronous reduced nasal and pharyngeal airways, which is correlated with the slightly flattened cranial base. Type I bicoronal patients have a smaller nasal cavity, but normally sized hypopharynx. Yet, type III patients developed normal nasopharyngeal airway volume overall.

One Versus Two Stages Surgery of Secondary Cheilorhinoplasty and Alveolar Cleft Grafting

Purpose: This study was planned to evaluate clinically and radiographically, the outcomes of secondary cheilorhinoplastyeither simultaneously with or six months after alveolar cleft grafting for patients with unilateral cleft lip nose deformity.Materials and Methods: Interventional, comparative study carried out on twenty patients with unilateral cleft lip nosedeformity, were divided randomly into two groups, group I: secondary cheilorhinoplasty was performed simultaneously withalveolar cleft grafting, group II: secondary cheilorhinoplasty was performed six months after it. Patients were assessed bothclinically and radiographically.Results: Clinically, significant improvement in functional results regarding NOSE scale and in aesthetic results of nose and lip postoperatively in both groups with no significant difference between them. Radiographically, significant improvement in thenasal airway volume and septal deviation postoperatively in both groups with no significant differences between them.Conclusion: No significant differences clinically and radigraphically between one and two stages surgery. Standardizedphotographs are efficient and can be used for aesthetic evaluation of nose and lip. CBCT and computer software are reliabletools for measuring nasal airway volume and septal deviation for assessment of nasal obsruction. NOSE scale is a reliable toolfor nasal function evaluation and POSAS is an efficient tool for scar assessment.

A Novel Classification of Relationship Between Nasal Septum and Inferior Turbinate Associated With Nasal Airway Obstruction in Patients With Unilateral Alveolar Cleft.

This study aims to investigate nasal morphologies associated with nasal airway obstruction in unilateral alveolar cleft patients. A total of 234 unilateral alveolar cleft cases were performed cone beam computed tomography scans. The digital imaging and communication in medicine data were imported into Simplant Pro software. The radiographic features including nasal septum deviation and inferior turbinate hypertrophy as well as nasal airway volume and sinusitis were analyzed. A new radiographic classification of relationship between nasal septum and inferior turbinate (NS-IT) on the cleft side was proposed and three types of NS-IT relationship (type I, II and III) were identified in 234 cases. The statistical analysis revealed that the nasal airway volume on non-cleft side was significantly higher than that on cleft side in each of three types (P < 0.0001), while no difference of nasal airway volume on non-cleft side was found among three types. In addition, the nasal airway volume on non-cleft side in type I and II was significantly higher than that in type III (P < 0.0001). Also, type III presented higher rate of maxillary sinusitis (P = 0.0154) and ethmoid sinusitis on cleft side (P = 0.0490) than type I and II. The other indexes including clinical variances were not significant among three types. Unilateral alveolar cleft patients with type III NS-IT relationship could have nasal airway obstruction and higher rate of maxillary and ethmoid sinusitis on cleft side, which may be taken into account at primary cleft repair and alveolar bone grafting treatment.