Differences in Pharyngeal Characteristics According to Angle Class of Malocclusion

SUMMARYObjectives: To investigate potential differences in the pharynx, the soft palate, the pharyngeal tonsil, and the tongue between patients with different Angle Classes of malocclusion.Study Design: Pre-treatment lateral cephalograms of 116 normal breathing individuals aged between 9 and 12 years were analyzed. 20 linear and 4 angular measurements, as well as 5 variables concerning the surface area of the pharynx and the soft palate were evaluated.Results: The angle formed by the palatal plane and the base of the skull had lower values in Class II groups. The soft palate height was smaller in Class II, div. 1 group. The angle between the soft and hard palates was smaller in Class III, followed by Class I, Class II, div. 2, and Class II, div. 1, with increasing values. The distance of the tongue from the palatal plane was larger in Class I and Class III groups. The surface area of the oropharynx was larger in Class III than in Class II groups. The total surface area of the pharynx had higher values in Class III than in Class II/1.Conclusion: Subjects with Class II malocclusion may be more prone to develop respiratory related disorders, such as obstructive sleep apnea, followed by Class I and Class III subjects.

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Mandibular symphysis morphology and dimensions in different anteroposterior jaw relationships

The Angle Orthodontist ◽

10.2319/030513-185.1 ◽

2013 ◽

Vol 84 (2) ◽

pp. 304-309 ◽

Cited By ~ 8

Author(s):

Susan N. Al-Khateeb ◽

Emad F. Al Maaitah ◽

Elham S. Abu Alhaija ◽

Serene A. Badran

Keyword(s):

Correlation Coefficient ◽

Alveolar Bone ◽

Pearson Correlation ◽

Class Ii ◽

Class I ◽

Pearson Correlation Coefficient ◽

Strongly Correlated ◽

Class Iii ◽

Mandibular Symphysis ◽

Lateral Cephalograms

ABSTRACT Objective: To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions. Materials and Methods: Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient. Results: Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r = 0.83 and between Id-Me and LAFH it was r = 0.81. Conclusions: The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.

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The duration of pubertal growth peak among three skeletal classes

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.21.5.067-074.oar ◽

2016 ◽

Vol 21 (5) ◽

pp. 67-74 ◽

Cited By ~ 3

Author(s):

Waqar Jeelani ◽

◽

Mubassar Fida ◽

Attiya Shaikh ◽

◽

...

Keyword(s):

Class Ii ◽

Growth Potential ◽

Class I ◽

Maturation Stage ◽

Class Iii ◽

Pubertal Growth ◽

Lateral Cephalograms ◽

Wide Range ◽

Significant Difference ◽

The Mean

ABSTRACT Introduction: Pubertal growth peak is closely associated with a rapid increase in mandibular length and offers a wide range of therapeutic modifiability. Objective: The aim of the present study was to determine and compare the mean ages of onset and duration of pubertal growth peak among three skeletal classes. Methods: A retrospective cross-sectional study was conducted using lateral cephalograms of 230 subjects with growth potential (110 males, 120 females). Subjects were categorized into three classes (Class I = 81, Class II = 82, Class III = 67), according to the sagittal relationship established between the maxilla and the mandible. The cervical vertebral maturation stage was recorded by means of Baccetti's method. The mean ages at CS3 and CS4 and the CS3-CS4 age interval were compared between boys and girls and among three skeletal classes. Results: Pubertal growth peak occurred on average four months earlier in girls than boys (p = 0.050). The average duration of pubertal growth peak was 11 months in Class I, seven months in Class II and 17 months in Class III subjects. Interclass differences were highly significant (Cohen's d > 0.08). However, no significant difference was found in the timing of pubertal growth peak onset among three skeletal classes (p = 0.126 in boys, p = 0.262 in girls). Conclusions: Girls enter pubertal growth peak on average four months earlier than boys. Moreover, the duration of pubertal growth peak is on average four months shorter in Class II and six months longer in Class III subjects as compared to Class I subjects.

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THE RELIABILITY OF BETA ANGLE IN ASSESSING CLASS II SKELETAL BASE IN MALABAR POPULATION

10.36106/ijar/1200937 ◽

2020 ◽

pp. 1-3

Author(s):

Sreehari S

Keyword(s):

Class Ii ◽

Class I ◽

Lateral Cephalograms ◽

Beta Angle ◽

Pre Treatment

The study aims to assess the ability of Beta angle, a cephlometric angle used to measure anterio - posterior skeletal base relationship to identify class II skeletal base.63 pre-treatment cephalograms were selected in to Class II group based on angle ANB, from 123 lateral cephalograms. The Beta angle values obtained were analyzed. The angle Beta is sensitive and specic in differentiating a Class II from a Class I

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A “new vista” in the assessment of antero-posterior jaw relationship

APOS Trends in Orthodontics ◽

10.4103/2321-1407.159412 ◽

2015 ◽

Vol 5 ◽

pp. 151-155

Author(s):

Divi Mittal ◽

Shivanand Venkatesh ◽

Prashantha Govinakovi Shivamurthy ◽

Silju Mathew

Keyword(s):

Sensitivity And Specificity ◽

Roc Curves ◽

Class Ii ◽

Class I ◽

Class Iii ◽

Operating Characteristics ◽

Lateral Cephalogram ◽

Skeletal Class ◽

Lateral Cephalograms ◽

Posterior Discrepancy

Aim The purpose of this investigation was to (1) compare the credibility of four recently introduced cephalometric measurements in assessing the antero-posterior jaw relationship; (2) To assess the correlation between various measurements used for assessment of antero-posterior discrepancy, including Yen linear, Yen angle, W angle and Pi angle. Materials and Methods The sample size for the study consisted of 45 subjects with age group of 15-19 years (mean age 17 ± 2.1) and was subdivided into Skeletal Class I, II and III groups of 15 each based upon the ANB angle derived from the pre treatment lateral cephalogram. Landmarks were located and Yen angle, Yen linear, W angle and Pi angle were assessed for each group. All the lateral cephalograms were traced by a single examiner. Intra examiner reliability was assessed by Intraclass co-efficient correlation (ICC) test. Correlation coefficients were obtained for each of parameters to compare their relationship with other parameters in Class I group. Receiver operating characteristics (ROC) curves were run to examine sensitivity and specificity of all the angles. Results The results showed that ICC for all the groups were ≥0.90 showing good repeatability of the measurements. There was statistically significant correlation between Yen angle and ANB angle, Yen linear and Yen angle for Class I group, between W angle and Yen angle for Class II group, between Yen angle, Yen linear and ANB for Class III group. ROC curves showed that Pi angle had 100% sensitivity and specificity to discriminate a Class II and a Class III group from a Class I and a Class III group from a Class II. Yen linear and W angle showed very low specificity to differentiate a Class II from a Class I group. Interpretation and Conclusion The new parameters considered in the study were found to be equally reliable and are not affected much by local remodeling due to tooth movements or by occlusal or Frankfurt horizontal plane. These parameters measure the antero-posterior discrepancy more consistently and accurately, with Pi angle being the most accurate.

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Evaluating Distance between Vibrating Line and Fovea Palatinae in Class I, Class II and Class III Soft Palate Types

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2020/v32i4331073 ◽

2021 ◽

pp. 78-86

Author(s):

Bharat Kumar ◽

Muhammad Abbas ◽

Asma Naz ◽

Naresh Kumar ◽

Shahid Ali ◽

...

Keyword(s):

Statistical Analysis ◽

Oral Health ◽

Soft Palate ◽

Class Ii ◽

Health Sciences ◽

Class I ◽

Age Group ◽

Class Iii ◽

Significant Difference ◽

The Mean

Objective: The objective of this study was to evaluate the mean distance between the vibrating line and fovea palatinae in Class I, Class II and Class III Soft Palate types. Methodology: This study was conducted at Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences Karachi among 197patients. Duration of study was six months. All patients were examined for vibrating line clinically, assessed using phonation method. Subsequently, distance between vibrating line and fovea paltatinae was measured with uncalibrated compass in various contours of soft palate. Results: Out of 197 patient, the vibrating line was seen in130 (64%) anterior to fovea palatinae, whereas, 67 (34%) vibrating line was at the fovea palatinae. The mean distance of those anterior located vibrating line from fovea palatine was calculated as 2.13 (±0.82) mm in Class, 2.07 (±0.69) mm in Class II and 1.80 (±0.82) mm in Class III soft palate contours. Statistical analysis showed no significant between gender, while statistically significant difference among age group and mean distance of anterior located vibrating line from fovea palatinae were found. Conclusions: The mean distance of vibrating line which is predominately found anterior to the fovea palatinae was 2.07 (±0.77) mm.

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Equation between Incisor Inclination Correction and Anteroposterior Movement of Point A to determine the Actual Magnitude of Maxillomandibular Difference

World Journal of Dentistry ◽

10.5005/jp-journals-10015-1454 ◽

2017 ◽

Vol 8 (4) ◽

pp. 300-303

Author(s):

Sathyashree Krishnamurthy ◽

Pooja Mehta

Keyword(s):

Class Ii ◽

Reference Plane ◽

Clinical Scenario ◽

Class Iii ◽

Center Of Rotation ◽

Lateral Cephalograms ◽

Angular Measurements ◽

The Mean ◽

Incisor Inclination ◽

Division 2

ABSTRACT Aim To determine the actual position of point A by performing incisor inclination correction in class II division 2 and class III. Also, to determine the relation between the degree of incisor inclination correction and anteroposterior movement of point A by studying pre- and postalignment lateral cephalograms. Materials and methods The pre- and postalignment lateral cephalograms of 33 class II division 2 and 33 class III patients treated orthodontically were traced manually and analyzed. The linear anteroposterior measurements of point A and center of rotation in relation to the vertical reference plane and angular measurements of upper incisor to maxillary plane were calculated. Results In class II division 2 category, the mean change in inclination from pre- to postalignment was 15.27°, mean change in position of center of rotation was -1.29 mm, and mean change in position of point A from pre- to postalignment was -2.67 mm. In class III category, the mean change in inclination from pre- to postalignment was -5.85°, mean change in position of center of rotation from pre- to postalignment was 1.94 mm, and mean change in position of point A from pre- to postalignment was 1.77 mm. Conclusion The results of the study confirmed that for every 10° proclination of the upper incisor in class II division 2, point A moves 0.3 mm palatally and for every 10° retroclination of the upper incisor in class III, point A moves 0.73 mm labially. Clinical significance In the clinical scenario of severely retroclined/proclined incisors, point A cannot depict the actual anterior limit of maxilla. Hence, when we use SNA to determine the anteroposterior position of maxilla and ANB to determine maxillomandibular difference, invariably we get altered values. Therefore, it is necessary to find an equation between the degree of incisor inclination correction and anteroposterior movement of point A. How to cite this article Shivamurthy PG, Krishnamurthy S, Mehta P, Mathew S. Equation between Incisor Inclination Correction and Anteroposterior Movement of Point A to determine the Actual Magnitude of Maxillomandibular Difference. World J Dent 2017;8(4):300-303.

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Twin block appliance: Effect on pharyngeal airway

Journal of Kathmandu Medical College ◽

10.3126/jkmc.v7i4.23299 ◽

2018 ◽

Vol 7 (4) ◽

pp. 147-152

Author(s):

Vivek Bikram Thapa ◽

Amrita Shrestha ◽

Prabesh Sherchan ◽

Prakash Poudel ◽

Luna Joshi

Keyword(s):

Soft Palate ◽

Class Ii ◽

Class Ii Malocclusion ◽

Twin Block ◽

Skeletal Class ◽

Pharyngeal Airway ◽

Skeletal Class Ii ◽

Obstructive Sleep ◽

Lateral Cephalograms ◽

Mandibular Retrusion

Background: Mandibular retrusion is the main cause of Skeletal Class II malocclusion characterized by skeletal retrusion of mandible with skeletal or dentoalveolar protrusion of maxillary. Objectives: This study was conducted to evaluate effect of treatment with twin-block appliances on pharyngeal dimensions. Methodology: This study was conducted in in the Department of Orthodontics & Dentofacial Orthopedics in Kathmandu Medical College. Twenty patients of age group 7 to 14 years with skeletal class II malocclusion with mandibular retrusion were selected. Variables evaluated were depth of nasopharynx; height of nasopharynx; depth of oropharynx; depth of hypopharynx; soft palate length; soft palate thickness and soft palate inclination. The lateral cephalograms were obtained for all subjects before the start of treatment and after a follow-up period of approximately three months in treatment. Results: Results showed that depth of nasopharynx increased by 1 mm, height of nasopharynx increased by 0.78 mm, depth of nasopharynx increased by 1.97 mm, depth of hypopharynx increased by 0.79 mm, soft palate length decreased by 4 mm, soft palate thickness increased by 2 mm and soft palate inclination decreased by 7.01 mm. The results for depth of pharynx and soft palate thickness were statistically significant. Conclusion: This study concluded that the use of twin block appliance for class II patients corrects sagittal dimension of oropharynx and hypopharynx. Early intervention for mandibular retrognathism in class II malocclusion helps enlarge the airway dimensions and decrease potential risk of obstructive sleep apnea syndrome for growing patients in the future.

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Mandibular symphysis morphology and lower incisor angulation in different anteroposterior jaw relationships and skeletal growth patterns – a cephalometric study

Medicine and Pharmacy Reports ◽

10.15386/mpr-1356 ◽

2020 ◽

Vol 93 (1) ◽

pp. 97-104

Author(s):

Sandhya Jain ◽

Prateek Puniyani ◽

Arwa Saifee

Keyword(s):

Sampling Method ◽

Class Ii ◽

Growth Patterns ◽

Class I ◽

Strongly Correlated ◽

Class Iii ◽

Lower Incisor ◽

Mandibular Symphysis ◽

Lateral Cephalograms ◽

Cephalometric Study

Objective. The purpose of the present study was to assess the symphyseal morphology and lower incisor angulation in different anteroposterior relationship and in different growth patterns and to investigate whether the symphyseal morphology had any correlation with dentofacial parameters. Method. Random Sampling method and lateral cephalograms of 90 subjects, age group 16-30 years, were divided into 30 in each group, i.e. Class I, Class II & Class III after calculating the following parameters (ANB angle, wits appraisal). After that, groups were again divided into 10 in each subgroup i.e. Average, Horizontal and Vertical growers. Results. Results showed the increase in actual symphysis width, inclination of the alveolar part, total height of symphysis and reduction in overall width along with retroclination of lower incisors in class III subjects as compared to class I and class II. Similarly actual and overall width of the symphysis were decreased and inclination of the alveolar part, symphyseal height and symphyseal ratio were increased in vertical growers. Conclusion. The dimensions and configuration of Mandibular Symphysis in class III was found to be different than those in Class I and Class II relationships; the alveolar part of Mandibular Symphyseal compensated for the skeletal relationship in the Class III pattern. Mandibualr Symphysis dimensions were strongly correlated to anterior facial dimensions. Similarly the dimensions and configuration of Mandibular Symphysis was also different in vertical growers as compared to horizontal and average growers, moreover symphyseal morphology and lower incisor angulation had a correlation with dentofacial parameters.

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Assessment of Positional Variation of Maxillary Permanent First Molar with respect to the Infrazygomatic Crest (Key Ridge) in Skeletal Class I, II and III Cases

World Journal of Dentistry ◽

10.5005/jp-journals-10015-1237 ◽

2013 ◽

Vol 4 (4) ◽

pp. 228-234 ◽

Cited By ~ 1

Author(s):

Ranjit Kamble ◽

Ananya Hazarey ◽

Pushpa Hazarey ◽

Jeet Singh

Keyword(s):

Vertical Plane ◽

Class Ii ◽

Class I ◽

Root Tip ◽

Control Group ◽

Class Iii ◽

Skeletal Class ◽

Permanent Molar ◽

Positional Variation ◽

Lateral Cephalograms

ABSTRACT Introduction To assess the positional variations of maxillary first permanent molar in horizontal and vertical plane with respect to infrazygomatic crest (key ridge) in skeletal class I, II and III cases. Materials and methods A total of 103 lateral cephalograms comprising of 40 skeletal class I (control group), 35 class II and 28 class III cases were selected and analyzed. Six parameters were chosen to compare the vertical and the horizontal variations of first permanent molars. Results The angulation of maxillary first molar with respect to key ridge in class II and III was 2.42° and 6.97° as compared to class I which was 5.35°. The mesiobuccal cusp tip of maxillary first molar from key ridge in class II and III was 2.11 and 5.46 mm respectively as compared to class I (1.62 mm). The mesiobuccal root tip of maxillary first molar from key ridge in class II and III was 2.14 and 2.82 mm as compared to class I (1.27 mm). Conclusion The maxillary first molar was not directly under the infrazygomatic crest and was ahead of the key ridge in all the groups. The maxillary first permanent molar was placed more mesially in class II and III cases as compared to the class I cases but, in class III, it was more upright as compared to class I and II. How to cite this article Kamble R, Hazarey A, Hazarey P, Singh J. Assessment of Positional Variation of Maxillary Permanent First Molar with respect to the Infrazygomatic Crest (Key Ridge) in Skeletal Class I, II and III Cases. World J Dent 2013;4(4):228-234.

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The SAR Angle: A Contemorary Sagital Jaw Dysplasia Marker

Orthodontic Journal of Nepal ◽

10.3126/ojn.v4i2.13891 ◽

2014 ◽

Vol 4 (2) ◽

pp. 16-20

Author(s):

Sonahita Agarwal ◽

Jitendra Bhagchandani ◽

Praveen Mehrotra ◽

Sudhir Kapoor ◽

Raj Kumar Jaiswal

Keyword(s):

Class Ii ◽

Mean Value ◽

Cutoff Point ◽

Class I ◽

Class Iii ◽

Receiver Operating Characteristic Curves ◽

Lateral Cephalograms ◽

Skeletal Pattern ◽

Beta Angle ◽

The Mean

Introduction: Cephalometric analysis forms the backbone of orthodontic diagnosis and treatment planning. However most of the angles used to assess antero-posterior jaw base discrepancy are based on landmarks that change with age, jaw rotation and orthodontic treatment. Walkers point is one landmark that has been suggested to be stable and easy to locate on radiograph.Objective: To derive SAR angle based on Walkers point, points M and G to assess true sagittal discrepancy.Materials & method: Sixty pretreatment lateral cephalograms of North Indian subjects were grouped in three classes of skeletal pattern based on fulfillment of any two of the three criteria: ANB angle, Witt’s appraisal and Beta angle. The mean and SD for the SAR angle in three groups were calculated. ANOVA one-way of variance and Newman-Keuls tests were done to compare the groups.Result: The mean value for SAR angle of Class I skeletal pattern group was 55.98o (SD 2.24), whereas mean value for Class II and Class III skeletal groups were 50.18o and 63.65o with standard deviations 2.70 and 2.25 respectively. The receiver operating characteristic curves show that the cutoff point between Class I and Class II groups could be considered a SAR angle of approximately 53o, and the cutoff point between Class I and Class III groups could be considered a SAR angle of approximately 59o.Conclusion: The SAR angle can be a reliable diagnostic aid to assess the sagittal jaw discrepancy more consistently.

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