ABSTRACT
SUMMARY: Subjects with maxillary skeletal classes II and III not only express alterations in the hard and soft maxillofacial tissues, but also in the morphology and dimensions of the upper airway. A small space in the upper airway has been associated with sleep disorders, such as snoring and mainly obstructive sleep apnea/hypopnea syndrome (OSAHS). Consequently, interest has increased due to the influence of orthognathic surgery in the airway space. Although there are studies in the literature that have compared upper airway spaces, most have evaluated the changes using two-dimensional images, mainly lateral skull X-rays. The present study aimed to determine the airway volume in subjects with skeletal classes II and III who underwent bimaxillary orthognathic surgery. 80 CBCT exams from 40 subjects obtained before and 6 months after surgery were used. There were 20 class II and 20 class III subjects. For the volumetric analysis, a 3D rendering of the upper airway was made in previously established segments, and then the airway volume was calculated using the 3D Slicer® software version 4.11 (Slicer, USA). The statistical analysis by t-test of related samples revealed statistically significant volumetric increases in the nasopharynx, laryngopharynx, and total volume in class II patients. However, in class III patients, there were significant increases in the nasopharynx and total volume, while the volume was maintained in the oropharynx and laryngopharynx.
Sujetos con clases esqueletales II y III maxilares, no solamente expresan alteraciones en los tejidos duros y blandos maxilofaciales, sino también en la morfología y dimensiones de la vía aérea superior. Un espacio reducido a nivel de la vía aérea superior se asocia a trastornos del sueño como ronquidos y principalmente el síndrome de apnea/hipoapnea obstructiva del sueño (AOS); debido a esto, ha aumentado el interés por la influencia de la cirugía ortognática en el espacio de la vía aérea. Si bien existen en la literatura estudios que han comparado los espacios de la vía aérea superior, la mayoría de los estudios han evaluado los cambios utilizando imágenes bidimensionales, principalmente radiografías laterales de cráneo. El objetivo del presente estudio fue determinar el volumen de la vía aérea en sujetos con clases esqueletales II y III sometidos a cirugía ortognática bimaxilar. Se utilizaron 80 exámenes CBCT pertenecientes a 40 sujetos obtenidos previo a la cirugía y 6 meses después de realizada. Veinte sujetos clase II y 20 clase III. Para el análisis volumétrico se realizó un renderizado 3D de la vía área superior en segmentos previamente establecidos y posteriormente se calculó el volumen de dicha vía aérea con la utilización del software 3D Slicer ®versión 4.11 (Slicer, USA). El análisis estadístico realizado por t-test de muestras relacionadas, arrojó en pacientes clase II aumentos volumétricos estadísticamente significativos en nasofaringe, laringofaringe y volumen total. Mientras que en pacientes clase III, se observó aumentos significativos en Nasofaringe y volumen total y mantención de volumen en orofaringe y laringofaringe.
Subject(s)
Humans , Pharynx/diagnostic imaging , Orthognathic Surgical Procedures , Pharynx/anatomy & histology , Cone-Beam Computed Tomography , Malocclusion, Angle Class II/surgery , Malocclusion, Angle Class III/surgeryABSTRACT
Abstract The aim of the study is to evaluate pharyngeal airway dimensions and hyoid bone position according to different Class II malocclusion types in Turkish population. Materials and Methods: The retrospective clinical study consisted of patients divided into 3 subgroups with skeletal Class II malocclusion. A total of 221 individuals (131 females and 90 males) were included in the study. Individuals with skeletal Class II malocclusion were divided into three subgroups as maxillary prognathia, mandibular retrognathia and combined. In the cephalometric analysis; 8 nasopharyngeal, 7 oropharyngeal, 2 hypopharyngeal, 9 hyoid measurements and 4 area measurements were used. The distribution of sex and growth-development stages of the patients were compared with the Pearson chi-square test. One-way ANOVA was used to evaluate patients. Tukey Post-Hoc tests were used for bilateral comparisons for significant parameters. SPSS package program was used for data analysis. Results were considered statistically significant at p0.05). When the position of the hyoid bone was evaluated, a statistically significant difference was found between the three groups in the measurements of Hy-Pg (mm) (p<0.05). Conclusion: Linear and areal nasopharyngeal airway dimensions are similar in subgroups of Class II malocclusions, while the distance of the hyoid bone from the pogonion is less in the mandibular retrognathia group.
Resumen El objetivo del estudio es evaluar las dimensiones de las vías respiratorias faríngeas y la posición del hueso hioides según los diferentes tipos de maloclusión de clase II en la población turca. Materiales y métodos: El estudio clínico retrospectivo consistió en pacientes divididos en 3 subgrupos con maloclusión esquelética de Clase II. Un total de 221 individuos (131 mujeres y 90 hombres) fueron incluidos en el estudio. Los individuos con maloclusión esquelética de Clase II fueron divididos en tres subgrupos como prognatismo maxilar, retrognatismo mandibular y combinados. En el análisis cefalométrico se utilizaron 8 medidas nasofaríngeas, 7 orofaríngeas, 2 hipofaríngeas, 9 medidas hioides y 4 medidas de área. La distribución del sexo y las etapas de desarrollo del crecimiento de los pacientes se compararon con la prueba de chi cuadrado de Pearson. Se utilizó un ANOVA unidireccional para evaluar a los pacientes. Las pruebas Tukey Post-Hoc se usaron para comparaciones bilaterales de parámetros significativos. El programa del paquete SPSS se usó para el análisis de datos. Los resultados se consideraron estadísticamente significativos a un nivel de significación p0.05). Cuando se evaluó la posición del hueso hioides, se encontró una diferencia estadísticamente significativa entre los tres grupos en las mediciones de Hy-Pg (mm) (p<0.05). Conclusión: Las dimensiones de las vías respiratorias nasofaríngeas lineales y areales son similares en los subgrupos de maloclusiones de Clase II, mientras que la distancia del hueso hioides al pogonion es menor en el grupo de retrognacia mandibular.
Subject(s)
Humans , Male , Female , Cephalometry/methods , Malocclusion, Angle Class II , TurkeyABSTRACT
Objective: This study aims to evaluate the pharyngeal airway dimensions among Chinese adults in relation to Class I and Class II facial skeletal patterns using three-dimensional cone-beam computed tomography (CBCT) images. Materials and Methods: A total of 156 initial CBCT images were evaluated, which were classified into skeletal Class I and Class II according to ANB angle with mean (SD) age being 22.56 ± 4.0 years and 22.32 ± 3.6 years. The pharyngeal airway volume, airway area, minimum cross-sectional area (MCA) and the distance from uvula (tip of the soft palate) to mental spine (U-MS distance) were assessed with Dolphin imaging software. Results: Compared with Class I group, Class II group displayed significantly smaller pharyngeal airway volume, airway area and MCA (P <.01, P =0.03, and P =0.008, respectively), and shorter U-MS distance (P <.001). Comparing gender subgroups, the female subgroup showed the smallest airway measurement. Spearman correlation test results showed that the airway volume and area had a significant positive correlation with U-MS distance (r = 0.22, P = 0.005, and r = 0.28, P < 0.005, respectively) and negative correlation with ANB angle (r = −0.23, P = 0.002, and r = −0.21, P = 0.007, respectively). Conclusions: Pharyngeal airway volume, airway area, MCA, and the U-MS distance were smaller in skeletal Class II than Class I Chinese adult subjects and lower in female Class II subgroup. Additionally, there was a correlation observed between the mandibular distance (U-MS), ANB angle and airway size.
ABSTRACT
This study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of the patients with skeletal class II division 1 or division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group (79 for pre-peak, 40 for peak, 40 for post-peak). Total 159 lateral cephalograms (70 for skeletal class I, 51 for skeletal class II, division 1, and 38 for skeletal class II, division 2) were selected.The growth of anteroposterior dimension of the pharyngeal airway were statistically significant among growth periods. The dimension for the nasopharyngeal and oropharyngeal airway space was the smallest in the division 1 skeletal class II group followed by class II division 2 and skeletal class I.
Subject(s)
Adolescent , HumansABSTRACT
OBJECTIVE: The purpose of this study was to compare the changes induced in the pharyngeal airway space by orthodontic treatment with bodily retraction of the mandibular incisors and mandibular setback surgery without extraction. METHODS: This retrospective study included 63 adult patients (32 men and 31 women). Thirty-three patients who had been treated via four-bicuspid extraction and bodily retraction of the mandibular incisors (incisor retraction, IR group) were compared with 30 patients who had been treated via mandibular setback surgery (MS group) without extraction. Lateral cephalograms were acquired and analyzed before (T1) and after treatment (T2). RESULTS: The superior pharyngeal airway space did not change significantly in either group during treatment. The middle pharyngeal airway space decreased by 1.15 ± 1.17 mm and 1.25 ± 1.35 mm after treatment in the IR and MS groups, respectively, and the decrease was comparable between the two groups. In the MS group, the inferior pharyngeal airway space (E-IPW) decreased by 0.88 ± 1.67 mm after treatment (p < 0.01). The E-IPW was larger in the MS group than in IR group at T1, but it did not differ significantly between the two groups at T2. No significant correlation was observed between changes in the pharyngeal airway space and the skeletal and dental variables in each group. CONCLUSIONS: The middle pharyngeal airway space decreased because of the posterior displacement of the mandibular incisors and/or the mandibular body. The E-IPW decreased only in the MS group because of the posterior displacement of only the mandibular body.
Subject(s)
Adult , Humans , Male , Incisor , Retrospective StudiesABSTRACT
BACKGROUND: The posterior movement of mandible was known as the main cause of the changes in the pharyngeal airway space (PAS) and the postoperative obstructive sleep apnea (OSA). The purpose of this study was to know the changes of PAS and position of hyoid bone. METHODS: Lateral cephalographies of 13 patients who had undergone sagittal split ramus osteotomy (SSRO) setback surgery were taken preoperatively (T1), postoperatively within 2 months (T2), and follow-up after 6 months or more (T3). On the basis of F-H plane, diameters of nasopharynx, oropharynx, and hypopharynx were measured. The movements of the soft palate, tongue, and hyoid bone were also measured. RESULTS: The amount of mandible setback was 7.5 +/- 3.8 mm. In the measurements of PAS, there was a statistically significant decrease of 2.8 +/- 2.5 mm in nasopharynx (P < 0.01), and 1.7 +/- 2.4 mm in oropharynx (P < 0.01) were observed after surgery. The hypopharynx decreased 1.0 +/- 2.1 mm after surgery and continuously decreased 1.0 +/- 2.8 mm at follow-up. The changes in hyoid bone position showed the posterior movement only after surgery and posteroinferior movement at follow-up. CONCLUSIONS: The PAS such as nasopharynx, oropharynx, and hypopharynx showed relatively high correlation with the amount of mandibular setback. The change of resistance in upper airway may be important for the prevention of OSA after mandibular setback surgery.
Subject(s)
Humans , Follow-Up Studies , Hyoid Bone , Hypopharynx , Mandible , Nasopharynx , Oropharynx , Osteotomy, Sagittal Split Ramus , Palate, Soft , Retrospective Studies , Sleep Apnea, Obstructive , TongueABSTRACT
OBJECTIVES: The purpose of this study was to evaluate changes in the pharyngeal airway space and hyoid bone position after mandibular setback surgery with bilateral sagittal split ramus osteotomy (BSSRO) and to analyze the correlation between the amount of mandibular setback and the amount of change in pharyngeal airway space or hyoid bone position. MATERIALS AND METHODS: From January 2010 to February 2013, a total of 30 patients who were diagnosed with skeletal class III malocclusion and underwent the same surgery (BSSRO) and fixation method in the Division of Oral and Maxillofacial Surgery, Department of Dentistry at the Ajou University School of Medicine (Suwon, Korea) were included in this study. Lateral cephalograms of the 30 patients were assessed preoperatively (T1), immediately postoperatively (T2), and 6 months postoperatively (T3) to investigate the significance of changes by time and the correlation between the amount of mandibular setback and the amount of change in the airway space and hyoid bone position. RESULTS: Three regions of the nasopharynx, oropharynx, and hypopharynx were measured and only the oropharynx showed a statistically significant decrease (P<0.01). A significant posterior and inferior displacement of the hyoid bone was found 6 months after surgery (P<0.01). Analysis of the correlation between the amount of mandibular setback and the amount of final change in the airway space and hyoid bone position with Pearson's correlation showed no significant correlation. CONCLUSION: In this study, the oropharynx significantly decreased after mandibular setback surgery, and changes in the surrounding structures were identified through posteroinferior movement of the hyoid bone during long-term follow-up. Therefore, postoperative obstructive sleep apnea should be considered in patients who plan to undergo mandibular setback surgery, and necessary modifications to the treatment plan should also be considered.
Subject(s)
Humans , Dentistry , Follow-Up Studies , Hyoid Bone , Hypopharynx , Malocclusion , Nasopharynx , Oropharynx , Osteotomy, Sagittal Split Ramus , Retrospective Studies , Sleep Apnea, Obstructive , Surgery, OralABSTRACT
Facial deformities are related to morphological differences and the mandible position shows differences in maxillomandible relation. The aim of this research was to compare the pharyngeal airway space (PAS) in subjects with class II and class III facial deformities We included 28 adult subjects with skeletal characteristics associated to class II or class III according to the SNA angle and dental overjet; subjects with facial asymmetry and other facial deformities and subjects with facial trauma or facial surgery history were excluded. Cone beam computed tomography was realized (CBCT) to asses the nasopharynx, oropharynx, hypopharynx, as well as the distance measured between the mandible genial spine and hyoid bone; data analysis were realized by descriptive analysis and statistical analysis using t test with 0.05 to show statistical differences. Class II subjects presented minor values in all of the measurements; in the oropharynx and the hypopharynx we observed the most important differences, with nasopharynx showing statistically significant differences (p<0.05). In conclusion class II subjects presented a minor pharyngeal airway space and it is suggested that this information should be used in the diagnosis process and prior to surgical treatment.
Las deformidades faciales son asociadas a diferencias en la posición mandibular evidenciando diferencias en la relación maxilomandibular. El objetivo de esta investigación fue comparar el espacio aéreo faríngeo en sujetos con deformidad facial clase II y clase III. Se incluyeron 28 sujetos con características esqueletales asociadas a clase II o clase III seguidos de la evaluación del angulo SNA y el resalte dentario; se excluyeron los sujetos con asimetría facial y otras deformidades faciales y sujetos con historia de trauma facial o historia de cirugía facial; se realizó la tomografía computadorizada cone beam para evaluar el área de nasofaringe, orofaringe, hipofaringe y la distancia entre la espina geni mandibular y el hueso hioides; los datos se analizaron con estadística descriptiva y la prueba t usando un valor de 0,05 para establecer significancia estadística. Se observó que los sujetos de clase II presentaron valores menores a los sujetos clase III en todas las mediciones realizadas; en el área de orofaringe e hipofaringe se observaron las diferencias mas importantes, estadísticamente significativas (p<0,05). Se puede concluir que los sujetos con deformidad facial clase II presentan un espacio de vía aérea faríngea más estrecho y se sugiere que este temática sea resuelta en la etapa de diagnóstico previo a la selección de tratamientos quirúrgicos o no quirúrgicos.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Pharynx/anatomy & histology , Pharynx/diagnostic imaging , Malocclusion, Angle Class II , Malocclusion, Angle Class III , Oropharynx/anatomy & histology , Oropharynx/diagnostic imaging , Nasopharynx/anatomy & histology , Nasopharynx/diagnostic imaging , Cone-Beam Computed Tomography , Hypopharynx/anatomy & histology , Hypopharynx/diagnostic imagingABSTRACT
OBJECTIVE: The aim of this study was to evaluate long-term changes in the pharyngeal airway dimensions after functional appliance treatment in adolescents with skeletal Class II malocclusions. METHODS: Pharyngeal airway dimensions were compared between subjects with skeletal Class II malocclusions (n = 24; mean age: 11.6 +/- 1.29 years) treated with a Class II bionator and age-matched control subjects with skeletal Class I occlusions (n = 24; mean age: 11.0 +/- 1.21 years) using a series of lateral cephalograms obtained at the initial visit (T0), after treatment (T1), and at the completion of growth (T2). RESULTS: The length of the nasopharyngeal region was similar between adolescents with skeletal Class I and Class II malocclusions at all time points, while the lengths of the upper and lower oropharyngeal regions and the pharyngeal airway areas were significantly smaller in the skeletal Class II adolescents before treatment when compared to the control adolescents (p < 0.05). However, following treatment with a functional appliance, the skeletal Class II adolescents had increased pharyngeal airway dimensions, which became similar to those of the control subjects. CONCLUSIONS: Functional appliance therapy can increase the pharyngeal airway dimensions in growing adolescents with skeletal Class II malocclusions, and this effect is maintained until the completion of growth.
Subject(s)
Adolescent , Humans , Activator Appliances , MalocclusionABSTRACT
OBJECTIVE: Lateral cephalometric radiographs have been the main form of resource for assessing two dimensional anteroposterior airway changes. The purpose of this study was to evaluate the three dimensional volumetric change in the upper airway space in Class III malocclusion patients who underwent mandibular setback surgery. METHODS: Three dimensional cone-beam computed tomographs (CBCT) and their three dimensional reconstruction images were analyzed. The samples consisted of 20 adult patients (12 males and 8 females) who were diagnosed as skeletal Class III and underwent mandibular setback surgery. CBCTs were taken at 3 stages - Baseline (1.8 weeks before surgery), T1 (2.3 months after surgery), and T2 (1 year after surgery). Pharyngeal airway was separated according to the reference planes and reconstructed into the nasopharynx, the oropharynx and the hypopharynx. Measurements at Baseline, T1, and T2 were compared between groups. RESULTS: The result showed the volume of the pharyngeal airway decreased significantly 2.3 months after surgery (p < 0.001) and the diminished airway did not recover after 1 year post-surgery. The oropharynx was the most decreased area. CONCLUSIONS: These findings suggest that mandibular setback surgery causes both short-term and long-term decrease in the upper airway space.
Subject(s)
Adult , Humans , Male , Cone-Beam Computed Tomography , Hypopharynx , Malocclusion , Nasopharynx , Oropharynx , Orthognathic SurgeryABSTRACT
OBJECTIVE: CBCT has become popular for orthodontic diagnosis and treatment planning in recent times. The 3D pharyngeal airway space needs to be analysed using a 3D diagnostic tool. The aim of this study was to analyse the pharyngeal airway of different craniofacial morphology using CBCT. METHODS: The sample compromised 102 subjects divided into 3 groups (Class I, II, III) and 6 subgroups according to normal or vertical craniofacial patterns. All samples had CBCT (VCT, Vatech, Seoul, Korea) taken for orthodontic treatment. The pharyngeal airway was assessed according to the reference planes: aa plane (the most anterior point on the anterior arch of atlas), CV2 plane, and CV3 plane (most infero-anterior point on the body of the second & third cervical vertebra). The intergroup comparison was performed with one-way ANOVA and duncan test as a second step. RESULTS: The results showed the pharyngeal airway and anteroposterior width of group 2 (Class II) in aa plane, CV2 plane, CV3 plane were significant narrower than in group 3 (Class III). There was no significant difference between vertical and normal craniofacial patterns except for the anteroposterior pharyngeal width of Group 1 (Class I) in aa plane. CONCLUSIONS: Subjects with Class II patterns have a significantly narrower pharyngeal airway than those with Class III. However there was no difference in pharyngeal airway between vertical and normal craniofacial morphology.
Subject(s)
Cone-Beam Computed TomographyABSTRACT
BACKGROUND: Uvulopalatopharyngoplasty (UPPP) is one of the most common treatments for patients with obstructive sleep apnea syndrome (OSAS) who suffer from repetitive apnea and oxygen desaturation during sleep. It is important to properly manage the patient's airway in the PACU after surgery in order to prevent potential airway-related postoperative complications. METHODS: 20 patient cases of ASA I or II who were over 20 years old and had undergone UPPP under general anesthesia were reviewed. In PACU, Posterior pharyngeal airway space (PAS) was measured on a lateral cranial radiograph at both supine and sitting positions and the blood pressure and oxygen saturation were measured. RESULTS: PAS significantly increased in the sitting position (avg. 11.7 mm in supine, 15.7 mm in sitting, P < 0.05) but there was no influence on the blood pressure or oxygen saturation. CONCLUSIONS: PAS is associated with the patency of the airway and the increase of PAS in patients in the sitting position while in the PACU is helpful to airway management following UPPP.
Subject(s)
Humans , Airway Management , Anesthesia, General , Apnea , Blood Pressure , Oxygen , Sleep Apnea, Obstructive , Supine PositionABSTRACT
OBJECTIVE: The purpose of this study was to evaluate the upper airway dimensional change according to maxillary superior movement after orthognathic surgery and to identify the relationship between the amount of maxillary movement and upper airway dimensional changes. METHODS: The samples consisted of 24 adult patients (9 males and 15 females) who had a skeletal discrepancy and had received presurgical orthodontic treatment. They underwent Le Fort I superior impaction osteotomy and mandibular setback surgery. Cephalometric x-rays were taken at 3 stages - T0 (before orthognathic surgery), T1 (just or within 2 weeks after orthognathic surgery), T2 (6 months after surgery) RESULTS: 1, Pharyngeal airway space (PAS (R)-nasopharynx) was decreased after surgery (T1) but recovered at 6 months after surgery; 2, Pharyngeal airway space (PAS (NL)-palatal plane) was increased after surgery and at 6 months after surgery; 3, Pharyngeal airway space (PAS (OL)-occlusal plane) was increased at T1 and was decreased at T2; 4, Soft palate thickness was increased at T1 but it became the same or thinner at T2; 5, There is no statistically significant relation between the amount of maxillary superior movement and pharyngeal airway space. CONCLUSIONS: These findings suggested that the maxillary superior movement of about an average of 4.40 +/- 1.14 mm did not affect upper pharyngeal airway space changes.
Subject(s)
Adult , Humans , Male , Orthognathic Surgery , Osteotomy , Palate, SoftABSTRACT
PURPOSE: This study was aimed at measuring the changes in the hyoid bone position, tongue position, and pharyngeal airway space in subjects with mandibular setback osteotomies. METHODS: Twenty patients were evaluated retrospectively for their changes in pharyngeal airway space, tongue and hyoid bone positions. All patients underwent surgical mandibular setback using bilateral sagittal split osteotomies. The cephalometric analysis was performed preoperatively, and 1 week, 3-6 months, and 1 year postoperatively. RESILT: The hyoid bone moved inferiorly and posteriorly immediately after surgery, and it returned to the preoperative position during follow-up period. The nasopharyngeal airway space was not significantly changed after surgery. A considerable decrease in the oropharyngeal and hypopharyngeal airway spaces following mandibular setback surgery was found. The upper and lower tongue was posteriorly repositioned immediately after surgery. During follow-up period, the hypopharyngeal airway space and lower tongue posture returned to the preoperative positions, but the oropharyngeal airway space and upper tongue posture were not significantly changed. The position of pogonion remarkably changed to backward immediately after surgery, but slightly anterior advancement was found during follow-up period. CONCLUSION: Immediately after mandibular setback surgery, the oropharyngeal and hypopharyngeal airway spaces obviously decreased due to posterior and inferior repositions of the tongue and hyoid bone. During follow-up period, lower tongue and hyoid bone returned to the preoperative positions, it was related to advancement of the pogonion in this period. The narrowing of the oropharyngeal airway space and posterior movement of the upper tongue posture were relatively permanent after mandibular setback surgery. We suspected this phenomenon had an influence on maintaining the total volume of oral cavity against mandibular setback.
Subject(s)
Humans , Follow-Up Studies , Hyoid Bone , Mouth , Osteotomy , Posture , Prognathism , Retrospective Studies , TongueABSTRACT
Various studies have documented a variability of hyoid bone position in relation to changed mandibular position or head position. The aim of this study was to evaluate the hyoid bone position and inclination on the lateral cephalometric radoigraphs of two group of patients exhibiting Class I normal occlusion and Class III maloccluslon, so to verify the relatlonships between hyoid bone position, pharyngeal airway and relative mandibular position In the class I group, there were 16 femailes, while the Class III group consisted of males and females. The results were as follows 1. By the length of A-Aph, N-APH, and GoP-PPH, the hyoid of Class IIIgroup was more anteriorly and inferiorly positioned than Class I group 2. On the analysis of soft tissue airway, the measurement(PNS-ad) of Class III group were smaller than Class I group 3. In the comparison of the variances betwwen male and female, hyoid bone was inferiority positioned and showed sinificantly more lager pharyngetal with of haled tissue in the Class I male and In the Class III male, same tendancy about hyoid position and pharyngeal wldth was seen and more anteriorly positioned 4. There was no statiscally significances between pharyngeal airway measurements and relative mandidular position, but statistical significance between wits appraisal and hyold bone position was seen. 5. The S-N-Pog which shows relative mandibular protrusion inverse ratio in the in the analysis with A-APH , N-APH and Facial ratio with LAH-Mp also showed Inverse ratio.