Fatemeh Gorjizadeh; Maryam Javaheri Mahd; Abdo Rahim Maktabi
Abstract
Background: Prediction of the mesio-distal width of the unerupted premolars and canine is an important point to the practitioner.
Objectives: The main goal of this study was to find the relationship of the teeth size to be used when needed in treatments planning. Materials and Methods: 200 plaster casts ...
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Background: Prediction of the mesio-distal width of the unerupted premolars and canine is an important point to the practitioner.
Objectives: The main goal of this study was to find the relationship of the teeth size to be used when needed in treatments planning. Materials and Methods: 200 plaster casts including 5600 teeth were measured and studies. A caliper with accuracy of 0.1 mm was used for measuring teeth and most teeth were measured twice and the average value was considered as the teeth size. In all cases, the vernier calipers jaws were moved along the teeth longitudinal axis and the biggest width was measured in the contact point area.
Results: Tables of mesiodistal widths of the permanent teeth and some equations were prepared. The measurement difference varied from 0 to 0.04 mm. the average value of difference was 0.016 mm with SD of 0.02 mm. All teeth in male are bigger than those in female and this different is most evident in canine teeth, especially the lower jaw canine teeth.
Conclusions: At the end of this study an equation was found which was used to measure the total value of mesiodistal width of canine and premolar teeth of upper and lower jaws in a simple and exact way.
Mohammad Hossein Toode Zaeim; Soghra Yassaei; Hoori Mir Mohamad Sadeghi; Valiollah Rafiei
Abstract
Aim: A high percentage of the problems in finishing phase are due to tooth size imbalances that can be diagnosed in initial stages of treatment. The purpose of present study is to evaluate the frequency of anterior tooth size discrepancies by Bolton Analysis among class I, II and III malocclusions.Materials ...
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Aim: A high percentage of the problems in finishing phase are due to tooth size imbalances that can be diagnosed in initial stages of treatment. The purpose of present study is to evaluate the frequency of anterior tooth size discrepancies by Bolton Analysis among class I, II and III malocclusions.Materials and methods: The mesio-distal widths of six anterior teeth in 90 paired casts of patients (class I, II, and III), who were selected non-randomly, were measured. Chi-square test was performed to compare the frequency of anterior tooth size discrepancies between the three malocclusion groups. Analysis of variance was used to compare the mean anterior Bolton ratios as a function of skeletal anterior-posterior malocclusions and both genders. Mean mesio-distal width of six anterior teeth were compared by Analysis of variance in 3 skeletal malocclusion groups. Statistical differences were determined at the 95% confidence level.Results: Discrepancy was greater in class I and III than in class II. No sex difference was shown to exist in Bolton anterior ratio. mesio-distal width of upper laterals had greater variation coefficient.
Conclusion: Difference of mean anterior tooth size discrepancies among three skeletal class I, II and III malocclusions were not statistically significant.
Hamid reza Fattahi; Hamid reza Pakshir; Rohollah Razmdideh
Abstract
Introduction: This study was designed to compare the tooth size discrepancy as a factor of skeletal mal-occlusion in orthodontic patient population of Shiraz.
Materials and Methods: The study employed the pretreatment models of 200 patients, which were selected through a random available sampling method. ...
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Introduction: This study was designed to compare the tooth size discrepancy as a factor of skeletal mal-occlusion in orthodontic patient population of Shiraz.
Materials and Methods: The study employed the pretreatment models of 200 patients, which were selected through a random available sampling method. The mesiodistal dimensions of teeth were measured by digital electron calipers (accurate to 0.01 mm) and the Bolton indices were determined. The study population was divided into four malocclusion groups according to Angle classification (Class I, Class II Div 1, Class II Div 2 and Class III). The data were analyzed using ANOVA and Duncan tests by SPSS software and the level of significance was p<0.05.
Results: The mean anterior ratio (79.01) of the total malocclusion group had a statistically significant difference with that of Bolton (77.2) but no significant difference was found for the overall ratio. The posterior and overall ratios of Class III malocclusion group were statistically greater than the other malocclusion groups. However, regarding the anterior ratio, the Class Ill group had a greater mean than Class II with no difference with Class I malocclusion group.
Conclusion: Comparing the two types of Class II malocclusion for ratios, no significant differences were observed.