ORTHODONTICS
RELIABILITY OF PANORAMIC RADIOGRAPHS TO DETERMINE GONIAL AND FRANKFURT MANDIBULAR HORIZONTAL ANGLES IN DIFFERENT SKELETAL PATTERNS
Ali Maghsoudi Nejad 1a, Abdolreza Jamilian 1b, Shahin Emami Meibodi 1c, Ladan Hafezi 2d, Saeed Khosravi 3e, Salvatore Cappabianca 4f, Letizia Perillo 5g
1
Department of Orthodontics, Tehran Dental Branch, Islamic Azad University( IAU), Tehran, Iran
2
Department of Oral Radiology, Tehran Dental Branch, Islamic Azad University( IAU), Tehran, Iran
3
Department of Education Management, Tehran University of Medical Sciences( TUMS), Tehran, Iran
4
Departments of Radiology, Second University of Naples, Naples, Italy
5
Departments of Orthodontics, Second University of Naples, Naples, Italy a
DDS b
DDS, PhD, Professor, Fellow of Orthognathic Surgery c
DDS, Associate Professor d
DDS, Assistant Professor e
MSc, Lecturer f
PhD, Professor gDDS, PhD, Professor
Cite this article: Nejad AM, Jamilian A, Meibodi SE, Hafezi L, Khosravi S, Cappabianca S, Perillo L. Reliability of panoramic radiographs to determine Gonial and Frankfurt Mandibular Horizontal Angles in different skeletal patterns. Stoma Edu J. 2016; 3( 1): 81-85.
ABSTRACT
Received: August 8, 2015 Received in revised form: August 17, 2015
Accepted: May 3, 2016 Published online: January 18, 2016
Background: Gonial and Frankfurt mandibular plane angles are two of the most important measurements required for orthodontic treatment and orthognathic surgery. Currently, lateral cephalograms are used for the determination of Go and FMA angles; however, in this method, measuring individual gonial angles becomes difficult due to the superimposed images of anatomical structures in a lateral cephalogram. Objectives: The aim of the present study is to check the possible application of panoramic radiograph to determine gonial and Frankfurt mandibular plane angles. Material and Methods: A total of 90 panoramic and 90 cephalometric radiographs were obtained retrospectively from patients who attended our orthodontic clinic. The mean age of the patients was 18.9 ± 5.9 years. Gonial and Frankfurt mandibular angles were determined on both lateral cephalograms and OPGs and the patients were divided into three groups of horizontal, normal, and vertical growers. Pearson’ s correlation coefficient was used for data evaluation. Results: Pearson’ s correlation coefficient showed that there were significant correlations between the means of Gonial and Frankfurt mandibular plane angles determined by OPG and Lateral cephalograms.( p < 0.01) Conclusion: Panoramic radiograph can be reliably used to determine of gonial and Frankfurt mandibular angle and thus reduce the need for obtaining further cephalometric images from patients. Keywords: orthopantomograms, lateral cephalograms, Gonial angle( Go), Frankfurt mandibular plane angle( FMA), skeletal patterns evaluation.
1. Introduction
Gonial angle( Go) and Frankfurt mandibular plane angle( FMA) are two of the most important measurements required for orthodontics, dentofacial orthopedics and orthognathic surgery. Go and FMA are commonly used to indicate the vertical or horizontal growth pattern of patients. Go and FMA having mean values of 130 ° ± 7 ° and 25 ° ± 5 °, respectively, are good indicators of vertical and horizontal growth pattern. Increased values of these angles show downward and backward rotation of the mandible which is characteristic of high angle patients; while their decreased values would be indicative of upward and forward rotation of the mandible which is in return characteristic of horizontal growers. 1 Recognizing the growth pattern of patients is of utmost importance in the treatment planning phase. Currently, lateral cephalograms are used for the determination of Go and FMA angles; however, with this method, measuring individual gonial angles becomes difficult due to the superimposed images of anatomical structures in a lateral
* Corresponding author: Professor Abdolreza Jamilian, DDS, PhD No 2713, Vali Asr St. Tehran 1966843133, Iran Tel: 0098-21-22011892, Fax: 0098-21-22022215, e-mail: info @ jamilian. net
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