scholarly journals Analysis of Interarch Tooth Size Relationship in Nepalese Subjects with Normal Occlusion and Malocclusions

2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Rajeev Kumar Mishra ◽  
Dashrath Kafle ◽  
Rahul Gupta
Keyword(s):  
Study Groups ◽  
Class Ii ◽  
Class I ◽  
Tooth Size ◽  
Class Ii Malocclusion ◽  
Normal Occlusion ◽  
Size Discrepancy ◽  
Clinically Significant ◽  
Anterior Ratio ◽  
Overall Ratio

Introduction. A proportional relationship between the maxillary and mandibular teeth size is required for achieving good finish with proper overjet and overbite postorthodontic treatment. The aims and objectives of this study were to determine the anterior and overall Bolton’s ratio in Nepalese population, to compare Bolton’s ratio between subjects with normal occlusion, Class I malocclusion, and Class II malocclusion, to compare these results with Bolton’s norm, and to determine the frequency of clinically significant (beyond 2 SD) tooth size discrepancy compared to Bolton’s norm. Materials and Methods. The study models of the subjects with normal occlusion and Angle’s Class I malocclusion and Class II malocclusion and fulfilling the inclusion criteria were retrieved from department archives. An electronic digital caliper was used to measure mesiodistal tooth size of the maxillary and mandibular teeth anterior to the second molars. The study sample of 120 study models consisted of the normal occlusion group (n = 31), Class I malocclusion group (n = 47), and Class II malocclusion group (n = 42). These measurements were then used to obtain Bolton’s ratio in three groups of subjects. Bolton’s ratio of study groups was compared with each other and with Bolton’s original ratio. Results. The differences in tooth size ratio of the study groups were not significant statistically, when the groups were compared on the basis of malocclusion or gender. Statistically significant differences were exclusively observed between the study groups and Bolton’s original sample for the anterior ratio. The frequency of the clinically significant tooth size ratio discrepancy was lower for the overall ratio (9.1%) compared to the anterior ratio (22.5%). Conclusions. Bolton’s analysis on the Nepalese population sample shows that there was no significant difference observed on the anterior and overall tooth size ratios when these were compared based on Angle’s malocclusion classes or gender. The clinically significant anterior tooth size discrepancy was more prevalent than that of the overall ratio.

scholarly journals Overall and Anterior Tooth Size Ratios in a Group of Emiratis

2018 ◽  
Vol 12 (1) ◽  
pp. 655-663 ◽  
Author(s):  
Moaza Ghuloom Mohammad ◽  
Shazia Naser-ud Din ◽  
Amar Hassan Khamis ◽  
Athanasios E. Athanasiou
Keyword(s):  
Class Ii ◽  
Anterior Tooth ◽  
Class I ◽  
Tooth Size ◽  
Class Iii ◽  
Mean Values ◽  
Normal Occlusion ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy ◽  
Dental Casts

Objectives:The aims of this investigation in a group of Emiratis were (1) To study overall and anterior tooth size ratios in Class I normal occlusion, (2) To estimate overall and anterior tooth size ratios in different malocclusion groups, (3) To compare overall and anterior tooth size ratios in Class I normal occlusion with the Bolton standards, and (4) To determine the distribution of overall and anterior tooth size ratios ± 2 SD from Bolton mean values in all occlusion groups.Materials and Methods:In this cross-sectional investigation, consecutive patients’ files, including dental casts, were selected from the archives of orthodontic clinics of the Dubai Health Authority. The final sample was formed following the application of specific inclusion criteria. The sample consisted of 521 pairs of dental casts representing both sexes (males: 188; females: 333) and different malocclusion groups (Class I: 288; Class II: 110; Class III: 30) and Class I normal occlusion (93). The mean age of patients was 16.18y for Class I, 15.73y for Class II, 15.83y for Class III, and 16.55y for Class I normal occlusion. The dental casts were scanned and digitized by the first author using the Ortho Insight 3D laser scanner. Measurements were made regarding maxillary and mandibular sums of mesiodistal tooth dimension of the overall (6-6) and anterior (3-3) groups of teeth. Statistical analysis included descriptive statistics, pairedt-test and Analysis of Variance (ANOVA). The level of significance was set atp<0.05.Results:There were statistically significant differences among malocclusion groups with regard to overall and anterior tooth size ratios. However, the comparison between the Class I normal occlusion group and the Bolton standards showed no statistically significant differences. Only five cases in Class II malocclusion presented an anterior tooth size discrepancy outside plus 2 SD from Bolton mean values and one case in Class I malocclusion presented with an overall tooth size discrepancy outside plus 2 SD from Bolton mean values.Conclusion:This study of the different occlusion groups of the Emirati sample concluded that (a) Class I normal occlusion cases presented similar overall and anterior tooth size ratios to Bolton standards; (b) Overall and anterior tooth size ratios among different malocclusion groups exhibited statistically significant differences; (c) Five cases in Class II malocclusion presented an anterior tooth size discrepancy outside plus 2 SD from Bolton mean values, and (d) One case in Class I malocclusion presented an overall tooth size discrepancy outside plus 2 SD from Bolton mean values.

scholarly journals Thresholds for Clinically Significant Tooth-Size Discrepancy

2009 ◽  
Vol 79 (4) ◽  
pp. 740-746 ◽  
Author(s):  
Toshiya Endo ◽  
Kenji Uchikura ◽  
Katsuyuki Ishida ◽  
Isao Shundo ◽  
Kosuke Sakaeda ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Clinical Significance ◽  
Tooth Size ◽  
Class Iii ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy ◽  
Clinically Significant ◽  
Anterior Ratio ◽  
Overall Ratio ◽  
Large Groups

Abstract Objective: To determine an appropriate threshold for clinically significant tooth-size discrepancy using both a Bolton standard deviation (SD) definition and a millimetric definition. Materials and Methods: Mesiodistal tooth widths were measured in 250 pretreatment dental casts of patients with Class I, Class II, and Class III malocclusions. The anterior and overall ratios and the required amount of maxillary and mandibular corrections were calculated. The casts were divided into small, normal, and large groups according to the anterior and overall ratios categorized by the Bolton SD definition, and into small, normal, and large groups according to the required amount of maxillary and mandibular corrections expressed in millimeters. Results: The small and large anterior ratio groups which fell under the category of the 2 SD threshold did not always need maxillary or mandibular corrections greater than 2 mm, while the small and large overall ratio groups always needed maxillary and mandibular corrections greater than 2 mm. The small and large maxillary correction groups in the 2 mm threshold category did not always have anterior or overall ratios greater than 2 SDs from the Bolton mean. However, the small and large mandibular correction groups always had anterior ratios greater than 2 SDs and did not always have overall ratios greater than 2 SDs. Conclusions: The tooth-size discrepancies could be better expressed in terms of both percentage and actual amount of millimeters required for correction. The ratios outside 2 SDs from the Bolton mean and the discrepancies requiring more than 2 mm of maxillary and/or mandibular corrections are recommendable as the appropriate thresholds for clinical significance.

scholarly journals Effect of Bi-jaw Premolar Extractions on Tooth Size Discrepancy in an Indian Population having Class I Malocclusion: An in vitro Study

2017 ◽  
Vol 7 (2) ◽  
pp. 114-117
Author(s):  
Manish Sonawane ◽  
Ravindranath V Krishnan ◽  
Girish R Karandikar ◽  
Samay Tahilramani
Keyword(s):  
Indian Population ◽  
In Vitro Study ◽  
Class I ◽  
Tooth Size ◽  
Premolar Extraction ◽  
Indian Origin ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy ◽  
Overall Ratio

ABSTRACT Aim To evaluate the effect of bi-jaw premolar extractions on Bolton tooth size discrepancy in patients of Indian origin, all of which exhibited a bilateral Angle’s class I molar relationship. Materials and methods Ninety sets of pretreatment study casts, which constituted the sample for the study, were divided into three groups, namely, Bolton small (BS), Bolton normal (BN), and Bolton big (BB). Simulated bi-jaw extraction of premolars was carried out in four different combinations for each set of study cast. The four values of Bolton’s overall ratio (BOR) thus obtained were compared with the original BOR value. Results The BOR value reduced when subjected to any of the four combinations of bi-jaw premolar extractions. Conclusion Premolar extraction in any combination inevitably changes the BOR value, which potentially affects the settling of occlusion toward the finishing stages of orthodontic treatment. Clinical significance The present study provides an insight into the choice of bi-jaw premolar extraction combination for each of the three groups in patients exhibiting class I malocclusion in the Indian population. How to cite this article Tahilramani S, Karandikar GR, Krishnan RV, Sonawane M. Effect of Bi-jaw Premolar Extractions on Tooth Size Discrepancy in an Indian Population having Class I Malocclusion: An in vitro Study. J Contemp Dent 2017;7(2):114-117.

scholarly journals Determination of Bolton Norms for Indian Population Sample

2017 ◽  
Vol 7 (1) ◽  
pp. 33-36 ◽  
Author(s):  
TV Pawan Kumar ◽  
Prasad Chitra
Keyword(s):  
Population Sample ◽  
Tooth Size ◽  
Mean Values ◽  
Class 1 ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy ◽  
Anterior Ratio ◽  
Overall Ratio ◽  
Male Subjects

Introduction: Tooth size discrepancy varies between different ethnic groups and races. Bolton’s tooth size norms were originally determined in Caucasian population.Objective: To determine tooth size ratios for maxillary and mandibular dentition in Telangana population of Indian sample and to compare the ratios with standard Bolton norms.Materials & Method: The study sample comprised of 300 subjects (150 males and 150 females) aged between 14-25 years having Angle’s Class 1 molar relationship. Study models of all subjects were prepared and mesiodistal dimensions were measured to determine mean Bolton’s anterior ratio, overall ratio, over jet and overbite.Result: Evidence of sexual dimorphism was observed with Indian male subjects having greater mean values than the females. The determined mean for anterior tooth ratio was 80.88 ± 3.03%, overall tooth ratio 93.99 ± 3.11%, overjet 2.92 ± 0.62mm and overbite 2.96 ± 0.63mm. Statistically significant differences were found between Indian samples and Bolton Caucasian standards.Conclusion: The study provides evidence that tooth sizes are population specific. Mean values specific to particular population groups should be derived in order to make treatment planning more accurate and predictable.

scholarly journals Bolton ratio in subjects with normal occlusion and class-I malocclusion

2016 ◽  
pp. 24-28
Author(s):  
Hasnat Jahan ◽  
Md Zakir Hossain
Keyword(s):  
Gender Differences ◽  
Orthodontic Treatment ◽  
Permanent Dentition ◽  
Class I ◽  
Angle Class ◽  
Normal Occlusion ◽  
Pre Treatment ◽  
Anterior Ratio ◽  
Overall Ratio

Aim: To verify the presence of Bolton ratios [Overall ratio & Anterior ratio] in Bangladeshi individuals with normal occlusion and class-I malocclusion. Methods:The materials comprised 120 pre-treatment study cast [60 male & 60 female aged 13-17 years] ,divided into two groups,first group were selected from the models of 60 students who had normal occlusion without crowding [equal male & female] and second group were selected from 60 patients who had Angle class-I crowding[equal male &famale], applied for orthodontic treatment based on the following criteria –permanent dentition from the 1st right molar to the 1st left molar and no interproximal caries or restorations.Bolton anterior & overallratios were performed for the study casts of the subjects using slide caliper. Results: The results showed that  there was no significants differences between two groups .Also no significant gender differences were found in Bolton anterior& overall ratios. Ban J Orthod & Dentofac Orthop, April 2016; Vol-6 (1-2), P.24-28

scholarly journals Tooth Size Discrepancies among Different Malocclusions in a Japanese Orthodontic Population

2008 ◽  
Vol 78 (6) ◽  
pp. 994-999 ◽  
Author(s):  
Toshiya Endo ◽  
Ryota Abe ◽  
Hiroo Kuroki ◽  
Kenji Oka ◽  
Shohachi Shimooka
Keyword(s):  
Sex Differences ◽  
T Test ◽  
Class I ◽  
Tooth Size ◽  
Class Iii ◽  
Test Analysis ◽  
Size Correction ◽  
Clinically Significant ◽  
Overall Ratio ◽  
Student’S T

Abstract Objective: To identify the possible sex differences in anterior and overall tooth size ratios and to evaluate whether any differences exist in tooth size ratios and distributions of subjects with clinically significant tooth size discrepancies among Angle Class I, Class II, and Class III malocclusion groups with the corresponding skeletal characteristics in a Japanese population. Materials and Methods: Each malocclusion group comprised 60 subjects (30 males and 30 females). The mesiodistal width from first molar to first molar was measured on each pretreatment cast to the nearest 0.01 mm using digital calipers, and the anterior and overall ratios were calculated. Student's t-test, Welch t-test, analysis of variance, and χ2-test were performed for statistical analysis. Results: No statistically significant sex differences were found in anterior or overall ratio in any group. No significant differences in anterior or overall ratios were found among the malocclusion groups. No significant differences were found between the distributions of subjects with clinically significant tooth size discrepancies, categorized by the Bolton standard deviation definition and by the actual amount of change calculated for tooth size correction in millimeters, among the malocclusion groups except for the mandibular correction for the overall ratio between Class I and Class III subjects. Conclusion: Bolton's values can be used with confidence for the typical Japanese orthodontic population. The use of the actual millimeters of correction for the tooth size ratios could help orthodontists avoid underestimating the prevalence of clinically significant tooth size discrepancies.

Intermaxillary tooth size discrepancies among different malocclusion classes: a comparative study

2002 ◽  
Vol 26 (4) ◽  
pp. 383-387 ◽  
Author(s):  
Eman Alkofide ◽  
Hayder Hashim
Keyword(s):  
Size Analysis ◽  
Tooth Size ◽  
Class Iii ◽  
Mean Values ◽  
Normal Occlusion ◽  
Significant Difference ◽  
Important Diagnostic Tool ◽  
Males And Females ◽  
Anterior Ratio ◽  
Overall Ratio

The purpose of this study is to determine whether a difference exists in intermaxillary tooth size among different malocclusion groups in Saudi patients. The study consisted of 240 pretreatment orthodontic casts (Sixty cases in each malocclusion class, in addition to normal occlusion). The results of the study shows no significant difference in the incidence of tooth size discrepancies for the overall ratio and anterior ratio between the different malocclusion groups, except for the anterior ratio in class III malocclusion. Further, no statistical significant difference was observed between males and females. When the mean values of the present study were compared to that of Bolton's, a significant difference was found in all the malocclusion classes.We can conclude from this study that Bolton tooth size analysis is an important diagnostic tool, and should be taken into consideration before initiation of orthodontic treatment.

scholarly journals Mesiodistal Crown Diameter of Normal Occlusion and Different Malocclusion Groups for a Sample of Kurdish Population of Erbil City

2020 ◽  
Vol 10 (1) ◽  
pp. 32-37
Author(s):  
Rawand J. Othman ◽  
Jameel A. Alkhashan
Keyword(s):  
Class Ii ◽  
Division I ◽  
Class I ◽  
Tooth Size ◽  
Class Iii ◽  
Crown Diameter ◽  
Lower Canine ◽  
Tooth Width ◽  
Normal Occlusion ◽  
Division Ii

It is essential to know the tooth crown size to provide accurate diagnosis and treatment planning to ensure the satisfactory outcome of orthodontic treatment. The aim of the present study was to measure and compare mesiodistal crown diameter of a Kurdish sample in Erbil city with normal and different classes of malocclusion. The mesiodistal tooth width was measured by an electronic digital caliper on a total of 150 (75 males and 75 females) orthodontic models of secondary school students of different occlusal relationships (Class I normal occlusion, Class I, Class II division I, Class II division II, and Class III malocclusions). The results showed that (1) the maxillary right first molar was significantly larger than the left one and both maxillary right lateral incisors and first premolars were larger than their contralateral teeth at the level of P < 0.01. (2) Both upper and lower canine were significantly smaller in females than in males; (3) Class I malocclusion showed tendency toward larger teeth than the rest of the other occlusal categories; (4) no statistically significant differences in tooth size were found among the Class II division I, division II, and Class III malocclusions when compared to normal occlusion. In conclusion, females had smaller teeth than males and there was asymmetry between the right and left sides in tooth size and Class I malocclusion showed tendency toward larger teeth.

Sign in / Sign up

Export Citation Format

Share Document