Mostafa Shahabi; Farzin Heravi; Naser Firoozi
Abstract
Aim: Some cphalometric angles change during growth and in accordance with facial height and other 'facial landmarks which make it less reliable for orthodontic diagnosis. The purpose of this study was to find out relationship between Beta Angle and the anterior-posterior position of jaws.
Materials ...
Read More
Aim: Some cphalometric angles change during growth and in accordance with facial height and other 'facial landmarks which make it less reliable for orthodontic diagnosis. The purpose of this study was to find out relationship between Beta Angle and the anterior-posterior position of jaws.
Materials and Method: Sixty lateral cephalograms of 16 boys and 44 girls with class I, H or HI malocclusions were evaluated in our study. we traced all of the cephalograms to measure Beta angle and compare these values between different types of malocclusions. Data were annalized by means of T-student statistical test.
Results: Beta angle was 28.5° - 37.5° for class 1, less than 28.5° for class II and more than 37.5° for class III. There was no correlation between t3 angle and facial height.
Conclusion: Beta angle is independent from facial height. Beta Angle has an acceptable specificity and sensitivity for determining the anterior posterior position of Jaws (IJO 2006; 1: 184-7).
Farzin Heravi; Alireza Pourali
Abstract
Aim: Tanaka and Johnston have offered a very simple method for estimating mesio-distal witdh of unerupted canines and premolars; But it seems that these estimations are not appropriate for Iranian population. In this investigation we've tried to offer a new formula to estimate the width of unerupted ...
Read More
Aim: Tanaka and Johnston have offered a very simple method for estimating mesio-distal witdh of unerupted canines and premolars; But it seems that these estimations are not appropriate for Iranian population. In this investigation we've tried to offer a new formula to estimate the width of unerupted teeth in Iranians.
Material and method: In this study we measured the size of premolars and canins on 400 dental casts and did a regression analysis to find any correlation between the size of these teeth and four lower incisors.
Results: We found that using Tanaka and Johnston analysis in Iranian children, unerupted teeth estimated wider than actual size.This study showed that there was a strong correlation between the width of lower incisors and unerupted canine and premolars of both jaws in Iranian population.
Conclusion: As we found Tanaka and Johnson's formula will estimate canines and premolars wider and a new formula is offered for Iranian population.
