Changes In Upper Airway Research Articles

Quantifying Upper Airway Changes Following Mandibular Orthognathic Surgery.

The aim of this study was to quantify upper airway changes following mandibular orthognathic surgery. Treatment records of 50 patients who underwent mandibular orthognathic surgery were divided into 2 groups, that is, Group 1: Cases treated with Mandibular Advancement Surgery and Group 2: Cases treated with Mandibular Setback Surgery with 25 patients in each group. The Lateral Cephalogram and Acoustic Pharyngometry records of both groups were studied at T0 (01 week before surgery) and T1 (01 year postsurgery) for changes in linear airway measurements (Nasopharyngeal Airway Space - NAS, Superior Airway Space - SAS, Posterior Airway Space - PAS and Hypopharyngeal Airway Space (HAS)), hyoid bone position (Mandibular Plane Hyoid distance), mean area and mean volume. The percentage change and change in these parameters per millimeter advancement or setback of mandible at T1 was calculated. A significant increase in linear airway parameters (SAS and PAS); decrease in hyoid distance; and increase in volume and area of upper airway was observed at T1 in Group 1 and reverse was observed in Group 2. The change in airway parameters (SAS, PAS, mean volume and area) was more significant in Group 1 as compared to Group 2. In the current airway centric approach, meticulous assessment and prediction of long-term airway changes post surgery should be an integral part of ortho-surgical diagnosis and treatment planning and suitable modifications in the treatment plan must be made to cater for any potential adverse effects on airway.

Upper Airway Changes Following Different Orthognathic Surgeries, Evaluated by Cone Beam Computed Tomography: A Systematic Review and Meta-analysis.

This study sought to assess the upper airway changes following different orthognathic surgeries using cone-beam computed tomography. An electronic search of the literature was conducted in major electronic databases including Medline (PubMed), Web of Science, Scopus, and Open Grey for articles published up to January 20, 2018. Human studies that evaluated the changes in the volume and minimum cross-sectional area of the upper airway or its subdivisions in patients who had undergone orthognathic surgery by use of cone-beam computed tomography were included. Manual search of the bibliographies of the included articles was also conducted. The included studies underwent risk of bias assessment. A total of 1330 articles were retrieved. After excluding the duplicates and irrelevant articles, 41 studies fulfilled the eligibility criteria for this systematic review; out of which, 30 entered the meta-analysis. The majority of studies had a medium risk of bias. Mandibular setback, and maxillary advancement + mandibular setback decreased the volume of the upper airway (-6042.87 mm3 and -1498.78 mm3, respectively) and all its subdivisions in long-term (>3 months), except for the nasopharynx, the volume of which increased following maxillary advancement + mandibular setback. Mandibular advancement and maxillomandibular advancement both increased the upper airway volume in long-term (7559.38 mm3 and 7967.06 mm3, respectively); however, only the changes after the former procedure were significant. The minimum cross-sectional area increased after maxillomandibular advancement (161.43 mm2), and decreased following maxillary advancement + mandibular setback (-23.79 mm2) in long-term. There is moderate evidence to suggest that mandibular advancement is the only orthognathic movement that provides a statistically significant change in long-term upper airway volume.

Acoustic characterization of upper airway variations from wakefulness to sleep with respect to obstructive sleep apnea

The upper airway (UA) is in general thicker and narrower in obstructive sleep apnea (OSA) population than in normal. Additionally, the UA changes during sleep are much more in the OSA population. The UA changes can alter the tracheal breathing sound (TBS) characteristics. Therefore, we hypothesize the TBS changes from wakefulness to sleep are significantly correlated to the OSA severity; thus, they may represent the physiological characteristics of the UA. To investigate our hypothesis, we recorded TBS of 18 mild-OSA (AHI < 15) and 22 moderate/severe-OSA (AHI > 15) during daytime (wakefulness) and then during sleep. The power spectral density (PSD) of the TBS was calculated and compared within the two OSA groups and between wakefulness and sleep. The average PSD of the mild-OSA group in the low-frequency range (< 280Hz) was found to be decreased significantly from wakefulness to sleep (p-value < 10-4). On the other hand, the average PSD of the moderate/severe-OSA group in the high-frequency range (> 900Hz) increased marginally significantly from wakefulness to sleep (p-value <9 × 10-3). Our findings show that the changes in spectral characteristics of TBS from wakefulness to sleep correlate with the severity of OSA and can represent physiological variations of UA. Therefore, TBS analysis has the potentials to assist with diagnosis and clinical management decisions in OSA patients based on their OSA severity stratification; thus, obviating the need for more expensive and time-consuming sleep studies. Graphical abstract Tracheal breathing sound (TBS) changes from wakefulness to sleep and their correlation with Obstructive sleep apnea (OSA) were investigated in individuals with different levels of OSA severity. We also assessed the classification power of the spectral characteristics of these TBS for screening purposes. Consequently, we analyzed and compared spectral characteristics of TBS recorded during wakefulness (a combination of mouth and nasal TBS) to those during sleep for mild and moderate/severe OSA groups.

Morphologic and Aerodynamic Changes of Upper Airway in Pediatric Hemifacial Microsomia Patients Undergoing Distraction Osteogenesis.

Current studies on hemifacial microsomia (HFM) patients undergoing unilateral distraction osteogenesis (DO) mainly confined to description of facial morphology. This study was to investigate the effect of unilateral DO on upper airway in pediatric HFM patients using computational fluid dynamics. The investigators implemented the present retrospective study composed of 20 patients (age 9.5 ± 2.5 years, 11 males, 9 females) with moderate HFM performed unilateral DO on the ramus of mandible. Computational fluid dynamics models of the upper airway were obtained based on the computed tomography data sets which were taken before and 6 months after distraction. Morphologic and aerodynamic parameters were respectively computed and compared at peak inspiration. Paired t-tests were used to compare the differences between the before and after parameters with the significance set at P < 0.05. The authors observed that after DO, oropharynx and nasopharynx were the major expanded regions, average pressure increased in all cross-sections, average velocity decreased significantly except in the superior border of the epiglottis plane, and the airflow resistance significantly reduced in the whole upper airway (P < 0.05). The results indicate that unilateral DO may expand the constricted oropharynx and nasopharynx, obtain a relatively symmetrical airway shape and decrease the airflow resistance which consequently reduce the workload necessary for breathing and facilitate inspiration.

Computer-Assisted Quantitative Analysis of Drug-Induced Sleep Endoscopy for Obstructive Sleep Apnea/Hypopnea Syndrome.

To use computer-assisted quantitative measurements of upper airway changes during drug-induced sleep endoscopy (DISE) and to correlate these parameters with disease severities and physiologic changes in patients with obstructive sleep apnea/hypopnea syndrome (OSA). A retrospective study. Tertiary academic medical center. A total of 170 patients who failed continuous positive airway pressure therapy and then underwent upper airway surgery were enrolled. All patients received polysomnography and DISE preoperatively. We used ImageJ 1.48v to obtain maximal and minimal measurements, including cross-sectional areas and anterior-posterior and lateral diameters at 4 anatomic levels (retropalatal, oropharyngeal, retroglossal, and retroepiglottic) under DISE, and then computed the percentage changes. We analyzed the clinical values of DISE changes by computer-assisted analysis in patients with OSA and any correlations between these changes and polysomnography parameters. The percentage changes of upper airway showed significant collapses at all 4 anatomic levels (all P < .0001). We also found that the changes at retropalatal levels were significantly greater and that retroglossal levels were significantly smaller, while the changes of anterior-posterior diameters at retroglossal levels showed a significant positive association with apnea-hypopnea index and desaturation index. However, there were no statistically significant correlations between upper airway changes and obesity. Computer-assisted quantitative analysis could evaluate upper airway changes of OSA in an objective way and may help identify the sites of obstruction during DISE more accurately. Upper airway showed multilevel collapse with independent significant changes in patients with OSA, with the retropalatal and retroglossal levels playing important roles in particular.

Dynamic tongue base thickness measured by drug-induced sleep ultrasonography in patients with obstructive sleep apnea

The aim of this study was to determine the value of drug-induced sleep ultrasonography (DISU) for evaluating tongue base thickness (TBT) from the awake state to drug-induced sleep, to further understand the impact of dynamic changes in TBT in obstructive sleep apnoea (OSA) patients. From May 2017 to May 2018, thirty patients with OSA were prospectively recruited. Sleep was induced with propofol via use of a target-controlled infusion (TCI) system. The depth of sedation was monitored by the bispectral (BIS) index with BIS levels ranging from 50 to 70. The dynamic change in the tongue base from the awake state to drug-induced sleep was recorded. The correlation between TBT in the awake state and in drug-induced sleep with OSA severity was analysed. The mean TBT in drug-induced sleep was significantly greater than that in the awake state (66.2±4.8mm vs 61.6±4.6mm, P<0.001). TBT in drug-induced sleep was more correlated with AHI compared to TBT in the awake state (r=0.50 vs r=0.40). This study showed that TBT in drug-induced sleep had the largest AUC (Area Under the Curve) in the ROC (Receiver Operating Characteristics) analysis (0.875), providing a cut-off point of 63.20mm with 95% sensitivity for diagnosis of moderate versus severe OSA. Our findings validate the use of DISU in objectively assessing the tongue base collapse in OSA patients. It provides a convenient and non-invasive way to evaluate the upper airway changes in OSA patients in the future.

Changes of the upper airway and bone in microimplant-assisted rapid palatal expansion: A cone-beam computed tomography (CBCT) study.

To evaluate the changes of maxillary expansion and upper airway structure after microimplant assisted rapid palatal expansion (MARPE) using cone-beam computed tomography (CBCT). This retrospective study included 19 subjects (15 females and 4 males) aged 15-29 years old (mean, 19.95±4.39 years) with maxillary transverse deficiency treated with MARPE. CBCT was performed at the initial diagnosis and 3 months after MARPE treatment. Measurements were taken to evaluate the amount of total expansion, skeletal expansion, and dental expansion at the maxillary first premolar (P1), second premolar (P2), first molar (M1), second molar (M2) regions and upper airway changes. After MARPE treatment, the maxillary skeletal base expansion, skeletal expansion, alveolar expansion and dental expansion were achieved at the P1, P2, M1, M2 region. The nasopharyngeal volume significantly increased 8.48% after MARPE treatment compared with that before the treatment (P < 0.05). The change of nasal lateral width (NLW) was also significantly different before and after MARPE (P < 0.05). However, there were no statistically significant change in the oropharyngeal, palatopharyngeal, glossopharyngeal and airway total volume (all P > 0.05). MARPE can produce more transverse bone expansion, relieve maxillary transverse deficiency and improve upper airway ventilation.

Comparison of dimensions and volume of upper airway before and after mini-implant assisted rapid maxillary expansion.

To evaluate changes in dimensions and volume of upper airway before and after mini-implant assisted rapid maxillary expansion (MARME) and observe correlations between changes of upper airway and vertical skeletal pattern in young adults. In this retrospective study, 22 patients (mean age, 22.6 ± 4.5 years; 4 male 18 female) with transverse discrepancy underwent MARME. Cone beam computed tomography was taken before and 3 months after expansion. Vertical and horizontal dimensions and volume of the nasal cavity, nasopharyngeal, retropalatal, retroglossal and hypopharyngeal airway were compared before and after MARME. Correlations between changed volume and dimensions were explored, as well as the vertical skeletal pattern. Nasal osseous width, maxillary width, volume of the nasal cavity and nasopharynx increased significantly (P < .05). Enlarged nasopharyngeal volume correlated with increased nasal width at the PNS plane (P < .05). There were no correlations between expanded volume and maxillary width. No measurements except nasal cavity volume had a correlation with Sum angle. Increased maxillary width correlated negatively with hard palate thickness (P < .05). (1) MARME caused an increase in volume of the nasal cavity and nasopharynx, with expansion of nasal osseous width and maxillary width. (2) Enlarged nasal width at the PNS plane contributed to the increase in nasopharynx volume. Enlarged maxillary width showed no direct relation with increased volume. (3) In this study, it was unclear about the association between changes of the upper airway and vertical skeletal pattern because of complex structures. (4) Palate thickness affected skeletal expansion of the maxilla in MARME.

Age-related morphological changes in upper airway in adult patients with obstructive sleep apnea

Age-related morphological changes in upper airway in adult patients with obstructive sleep apnea

Upper Airway Changes following Functional Treatment with the Headgear Herbst or Headgear Twin Block Appliance Assessed on Lateral Cephalograms and Magnetic Resonance Imaging.

Objective The present study compared the changes in the upper airway dimensions and sleep-related breathing disorder (SRBD) condition between functional treatment with the headgear Herbst (HG-Herbst) and headgear Twin Block (HG-TB) appliance. Soft tissues were assessed on lateral cephalometric X-ray and magnetic resonance imaging (MRI). Materials and Methods Consecutive patients who sought orthodontic treatment at the Faculty of Dentistry of The University of Hong Kong were screened. Adolescents (12-17 year sold for boys and 10-15 years old for girls), with class II molar relationship and overjet >5 mm, with no severe transverse maxillary deficiency, were recruited. Patients were assigned either to the HG-Herbst or to the HG-TB treatment by stratified block randomisation, with sex as the stratification factor. Lateral cephalograms, magnetic resonance imaging (MRI), and the Paediatric Sleep Questionnaire (PSQ) were obtained at baseline and after treatment. Results 28 patients were enrolled, and 26 patients (13 in each group) completed the treatment. Following 1 year of functional appliance treatment, a significantly lower increase of the lower anterior facial height was observed in the HG-Herbst group compared to the HG-TB group (p = 0.024). However, no significant differences were observed in the upper airway structures or SRBD between the two groups. Conclusion The changes in upper airway dimensions and SRBD condition were not significantly different between the HG-Herbst and the HG-TB appliance treatment. Additional studies with larger sample size are warranted.

The Efficacy of Autologous Nebulized Platelet Rich Plasma (PRP) As an Early Adjuvant Therapeutic and Prognostic Treatment Modality in the Management of Inhalation Lung Injury

Background: Despite considerable advances in our knowledgeof the pathophysiology of inhalation injury, there arefew specific therapeutic options, and patient care is mainlysupportive. Platelets release growth factors and other immunesystem components to start healing process. By using nebulizedPlatelet Rich Plasma (PRP), platelets may reduce inflammationand stimulates bronchial tree healing. However, there are noclear data supporting or refuting the use of inhaled PRP ininhalation injury.Objective: To evaluate the role of nebulized autologousPlatelet Rich Plasma (PRP) in management of Smoke InhalationInjury (SII) as early adjuvant therapeutic and prognosticmodality.Methods: This is prospective study that included 40patients with burns 25-50% TBSA and have inhalation lunginjury. They were divided into 2 groups; 20 patients receivedaerosolized particles of nebulized PRP beside regular regimen.The other control group included 20 patients and receivedregular treatment regimen only.Results: There was a statistical significant difference(p<0.01) of biologic changes in upper airway with smokeinjury in study group patients compared to control grouppatients who received regular protocol measured at the samefollow-up time interval, relatively same TBSA and initialbronchoscopy scoring. The mean extubation time was 7±1days in study group compared to 14±1 days in control group.Study group less showed shorter hospital stay and less mortalityrate.Conclusion: The application of aerosolize the PRP solutionin the nebulizer with regular treatment protocol of inhalationburn patients could be a beneficial therapeutic tool for regeneratingof post burn damaged tracheo-broncho-pulmonarytree. Further studies on larger patient population with clinicaland pathological evidences are warranted

Effects of rapid maxillary expansion on upper airway volume: A three-dimensional cone-beam computed tomography study.

To compare changes in pharyngeal airway volume and minimal cross-sectional area (MCA) between patients undergoing rapid maxillary expansion (RME) and a matched control group and to identify markers for predicting airway changes using cone-beam computed tomography (CBCT). Pre- and posttreatment CBCT scans were selected of children who had RME (14 girls and 12 boys; mean age, 12.4 years) along with scans of a control group (matched for chronological age, skeletal age, gender, mandibular inclination) who underwent orthodontic treatment for minor malocclusions without RME. Changes in airway volume and MCA were evaluated using a standardized, previously validated method and analyzed by a mixed-effects linear regression model. Upper airway volume and MCA increased significantly over time for both the RME and matched control groups (P < .01 and P = .05, respectively). Although the RME group showed a greater increase when compared with the matched controls, this difference was not statistically significant. A reduced skeletal age before treatment was a significant marker for a positive effect on the upper airway volume and MCA changes (P < .01). Tooth-borne RME is not associated with a significant change in upper airway volume or MCA in children when compared with controls. The younger the skeletal age before treatment, the more positive the effect on the upper airway changes. The results may prove valuable, especially in RME of young children.

Residents' journal review

Residents' journal review

Volumetric upper airway changes following a new technique for Surgically-Assisted Maxillary Expansion (SAME).

Skeletal maxillary constriction (SMC) is one of the common skeletal discrepancies which are associated with alterations in the respiratory function. Today, many surgical techniques are used to expand the maxilla in adult patients with no consensus about the optimal technique. The present study aimed to investigate the changes of the upper airway volume resulting from the use of a new, minimally invasive surgically-assisted maxillary expansion (SAME) technique, and compare the results with the conventional SAME technique. A prospective study was conducted between September 2015 and July 2018. A total of 28 adult patients (11 males, 17 females; mean age: 19.1 ±2.7 years) with SMC underwent SAME. The sample was divided according to the applied surgical technique into 2 groups: the conventional osteotomy SAME (CO‑SAME) group consisted of 13 patients (18.7 ±2.2 years) and the selective osteotomy SAME (SO-SAME) group consisted of 15 patients (19.4 ±3.2 years). Cone beam computed tomography (CBCT) scans were initially obtained preoperatively (T1) and 3 months post expansion (T2). The upper airway was divided into 2 segments: retropalatal and retroglossal. The volume of each segment and the total airway volume (TAV) were assessed using the OnDemand3D® software. The total upper airway volume showed a significant increase after both CO‑SAME and SO-SAME (1.29 ±0.26 cc and 1.21 ±0.19 cc, respectively), with significant increases in retropalatal and retroglossal airway volumes (RPAV and RGAV) after both CO‑SAME and SO-SAME (RPAV - 0.73 ±0.10 cc and 0.83 ±0.10 cc, and RGAV - 0.56 ±0.23 cc and 0.38 ±0.23 cc, respectively). No significant differences were observed in the maxillary width (MW), TAV or RGAV between the 2 SAME techniques, whereas the increase in RPAV in the SO-SAME group was significantly greater than that of the CO‑SAME group. The new, minimally invasive SAME technique was an effective procedure to increase MW and the upper airway volume.

Three-dimensional evaluation of changes in upper airway volume in growing skeletal Class II patients following mandibular advancement treatment with functional orthopedic appliances.

The aim of this study was to assess three-dimensionally the upper airway changes following functional appliance treatment in growing Class II patients. Pre-and post-treatment Cone beam computed tomography scans of 20 patients (age range: 9 to 12; mean: 11.4 ± 1.0 years) were retrieved from the list of patients previously treated with functional appliances in the Postgraduate Clinic at the Section of Orthodontics, Aarhus University, Denmark. Total and partial volumes of the upper airway (ie, lower nasopharynx, velopharynx, and oropharynx) were calculated. To rule out the effect of growth, the changes in the functional appliance group were compared to an age-matched Class I group of 18 patients (age range: 8 to 14; mean: 11.8 ± 1.4 years). In the functional appliance group, all the partial and total volumes were significantly larger at the end of treatment when compared to the start of treatment ( P < .003). On the other hand, when comparing the changes for the total and partial volumes of the upper airway in the functional appliance group with the Class I group, a statistical difference was seen only for the oropharynx ( P = .022) and total volume ( P = .025), with the functional appliance group showing a larger volume increment. An increase in the upper airway volume was found after treatment with functional appliances. This difference was mainly related to the changes at the oropharynx level, which differed significantly from what was observed in the Class I group.

Soft palate cephalometric changes with a mandibular advancement device may be associated with polysomnographic improvement in obstructive sleep apnea.

It is unclear whether soft palate-associated changes in cephalometry associated with a mandibular advancement device (MAD) are independently associated with improvements in polysomnography (PSG) respiratory parameters in obstructive sleep apnea (OSA). This retrospective review aimed to identify the association between soft palate-associated changes in cephalometry and PSG changes after application of an MAD. Korean patients diagnosed with OSA who underwent cephalometry with or without an MAD were enrolled. All the patients were evaluated after undergoing full-night PSG twice: once with an MAD and once without. Cephalometric findings were measured using an image analyzer. Mean apnea-hypopnea index significantly decreased with an MAD from 36.4/h to 14.7/h (p<0.001). Retropalatal airway space significantly increased with an MAD from 6.6 to 7.3 mm (p=0.013). Soft palate length also significantly decreased with an MAD from 43.6 to 42.3 mm (p=0.02). Although these findings were shown by responders (patients with a reduction of apnea-hypopnea index by more than 50%), there were no significant changes in non-responders. However, retroglossal airway space did not significantly increase with an MAD even in responders. Improvement of OSA with an MAD can be predicted with soft palate-associated upper airway changes shown in cephalometry.

The influential factors on the morphological changes of upper airway associated with mouth opening.

This study aimed to evaluate the influential factors on the morphological changes of upper airway caused by mouth opening (MO). One hundred and thirty-eight obstructive sleep apnea-hypopnea syndrome (OSAHS) patients were enrolled. Anthropometric and demographic data, Friedman tongue position (FTP), and tonsil scores were recorded. Overnight polysomnography and upper airway computed tomography scans under two conditions (mouth closed [MC] and MO) were acquired. Morphological parameters of upper airway were compared between MC and MO. Stepwise multiple linear regression analyses were performed with the variation ratio of upper airway parameters (Para-VRs) from MC to MO as the dependent variable, with age, gender, body mass index, neck circumference, waist circumference, four mandibular indexes, net angle or amount of MO, FTP, and tonsil scores as the independent variables. Overall analysis and subgroup analyses based on OSAHS severity revealed that the minimal cross-sectional area of oropharyngeal lumen (OXmin) significantly decreased (P < 0.05) with MO, whereas the minimal cross-sectional area of velopharyngeal lumen (VXmin) did not significantly change with MO (P > 0.05). The net angle of MO or amount of MO combined with tonsil scores were identified to have significant positive correlation with EXP (OXmin-VR), [OXmin-VR was logarithmically transformed with an exponential function, EXP(n) = en ]; FTP appeared to be more related to EXP (VXmin-VR). Mouth opening induced a significant increase VXmin for patient subgroup with FTP grading I and a significant decrease VXmin for patient subgroup with FTP grading IV (P < 0.05). Wider MO combined with larger tonsils lead to narrower oropharyngeal airway. The relative position of tongue to soft palate is the main factor influencing the changes of velopharyngeal lumen with MO. 4 Laryngoscope, 128:2902-2909, 2018.

Impact of Bimaxillary Advancement Surgery on the Upper Airway and on Obstructive Sleep Apnea Syndrome: a Meta-Analysis

Upper airway changes following bimaxillary advancement surgery to treat obstructive sleep apnea syndrome remain controversial. The main objective of this systematic review and meta-analysis was to investigate the effects of bimaxillary advancement surgery on the upper airway (UA) of obstructive sleep apnea syndrome patients through examining changes three-dimensionally in vertical and supine position and through changes in oximetric variables (AHI, RDI, O2 Sat) and in the quality of life measured by the Epworth sleepiness scale (ESS). A thorough search of the PubMed, Scopus, Embase and Cochrane databases and a grey literature search (Opengrey) were conducted. No limit was placed on publication year or language. The inclusion criteria were: adult obstructive sleep apnea patients who had undergone bimaxillary advancement surgery, three-dimensional CBCT or CT and oximetric measurements and at least six weeks follow-up. Sample sizes of under 10 patients were excluded. Finally, 26 articles were included in the qualitative review and 23 in the meta-analysis. Bimaxillary advancement surgery has been shown to be beneficial in terms of increased upper airway size, improved oximetric indicators and the quality of life measured on the Epworth sleepiness scale.

Assessing the validity of ITK-SNAP software package in measuring the volume of upper airway spaces secondary to rapid maxillary expansion.

INTRODUCTION:The purpose of this study is to evaluate the validity of a free-access software package (ITK-SNAP) in segmenting and measuring the volume of upper airway spaces secondary to rapid maxillary expansion (RME).MATERIALS AND METHODS:Sixteen participants who required RME were recruited for this study. Preoperative (T1) and 6-month postoperative (T2) cone-beam computed tomographic scans of all participants were analyzed. OnDemand3D software packages was used for superimposition and orientation of the images, while ITK-SNAP software was used to measure the volume of airway spaces. At week one (W1), all volumetric measurements were carried out by one examiner and repeated after 1 week (W2). Paired t-test, the interclass correlation coefficient, and Dahlberg coefficients of reliability were used to assess the reproducibility.RESULTS:Student's t-test showed no significant difference between the W1 and W2 set of measurements (P > 0.05). Coefficients of reliability were above 95% and intraclass correlation coefficient ranged from 0.99 to 1.000, which altogether confirmed the satisfactory reproducibility of the measurements.CONCLUSIONS:ITK-SNAP software package is a reliable and cost-effective method to segment and measure upper airway changes subsequent to RME.

Bond Strength to Primary Teeth Dentin Following Disinfection with 2% Chlorhexidine

The aim of the study is to evaluate morphological changes in upper airways in patients undergoing therapy with removable functional orthopedic devices used in the treatment of the II skeletal classes by mandibular retraction.