title: Correlation of Beta Angle with Antero-Posterior Dysplasia Indicators and FMA: An Institution Based Cephalometric Study.
abstract: BACKGROUND
  Beta angle utilizes three skeletal landmarks - point A, point B, and point C (the apparent axis of the condyle). It is formed between A-B line and point A perpendicular to C-B line. Further this angle indicates the severity and the type of skeletal dysplasia in the sagittal dimension and it changes with the growth pattern of the patient. Hence, it is important to study the dependence of beta angle on the growth pattern.
  
  
  OBJECTIVE
  The present study was designed to evaluate the correlation of Beta angle with point A-Nasion-point B (ANB) angle, points A and B to palatal plane (App-Bpp), Wit's appraisal and Maxillary-Mandibular plane angle Bisector (MMB) and Frankfort-Mandibular plane Angle (FMA) in Skeletal Class I, Class II and Class III malocclusion groups.
  
  
  METHODS
  Pre-treatment lateral head cephalo-grams of 120 subjects in age group of 15-25 years were obtained. Three skeletal Class I, Class II and Class III malocclusion groups (40 each) were assorted on the basis of ANB, MMB, App-Bpp, Wit's appraisal and FMA. Analysis of variance (ANOVA) and mean differences were calculated to compare the study groups. Bivariate correlations among different parameters of these groups were obtained.
  
  
  RESULTS
  Normal values of beta angle in skeletal Class I group, skeletal Class II group and skeletal Class III group was 31.33±3.25, 25.28±4.28 and 40.93±4.55 respectively. Overall beta angle showed a strong correlation with all parameters of anterio-posterior dysplasia indicators except FMA.
  
  
  CONCLUSIONS
  Beta angle shows weak correlation with FMA and is not affected by growth pattern/jaw rotation. The normal values are in same range irrespective of the differences in craniofacial morphology.
authors.affiliation: Senior Lecturer, Department of Orthodontics and Dentofacial Orthopedics, Genesis Institute of Research and Dental Science , Ferozepur, Punjab, India .
authors.forename: Gurinder
authors.initials: G
authors.lastname: Singh
authors.affiliation: Associate Professor, Department of Orthodontics and Dentofacial Orthopedics, Dr. Harvansh Singh Judge Institute of Dental Sciences , Panjab University, Chandigarh, India .
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Verma
authors.affiliation: Senior Lecturer, Department of Orthodontics and Dentofacial Orthopedics, Dr. Harvansh Singh Judge Institute of Dental Sciences, Panjab University , Chandigarh, India .
authors.forename: Devinder Preet
authors.initials: DP
authors.lastname: Singh
authors.affiliation: Reader, Department of Orthodontics and Dentofacial Orthopedics, Mithila Minority Dental College and Hospital , Darbhanga, Bihar, India .
authors.forename: Sumit Kumar
authors.initials: SK
authors.lastname: Yadav
authors.affiliation: Demonstrator, Department of Oral Pathology and Microbiology, Post Graduate Institute of Dental Sciences , Rohtak, Haryana, India .
authors.forename: Achla Bharti
authors.initials: AB
authors.lastname: Yadav
keywords: Bivariate correlations; Malocclusion; Skeletal dysplasia