Bolton tooth size discrepancy among different malocclusion groups in two different ethnic groups of Nepalese population

Introduction: The tooth size ratios may vary among different ethnic groups and different malocclusion groups. The objective of this study is to see the tooth size discrepancies in two major ethnic groups of Nepal; Indo-Aryans and Tibeto-Burmans and different malocclusion groups and compare it with the Bolton’s study. Materials and Method: The anterior and overall ratios were compared between Indo-Aryans and Tibeto-Burmans according to different malocclusion groups with Bolton’s study with one sample t-test. The differences in ratios in ethnic groups and gender were seen with one sample t-test. The differences in mesio-distal tooth width amongst the two ethnic groups were seen. One sample ANOVA was used to see any correlation between the ethnic groups and the different malocclusion groups. Result: The anterior ratio and overall ratio in Indo- Aryans and Tibeto-Burmans in all the malocclusion groups were greater than the Bolton’s study but was not statistically significant. There was significant differences in anterior ratio between Indo-Aryans (77.63 + 2.74%) and Tibeto-Burmans (78.51 + 2.76%), p value= 0.024. There were no statistical significant differences in the anterior and overall ratio amongst males and females. The mesio-distal tooth size was greater in Tibeto-Burmans as compared to Indo-Aryans expect for maxillary right and left central incisors. Conclusion: The Tibeto-Burmans had higher anterior ratio as compared to Indo-Aryans. The Tibeto-Burmans had broader teeth as compared to Indo-Aryans except for maxillary central incisors.

Digital analysis of tooth sizes among individuals with different malocclusions: A study using three-dimensional digital dental models

Objective: It is aimed to examine the tooth sizes of digital models of patients with different malocclusions with the help of three-dimensional measurement software. Methods: Digital models of 252 patients aged between 13 and 25 years of age were included. According to the Angle classification, three different malocclusion groups were allocated such that there were 84 patients in each group, plaster models of patients scanned with the three-dimensional model browser 3Shape R700 3D Scanner (3Shape A/S Copenhagen, Denmark) and transferred to the digital format. 3Shape Ortho Analyzer (3Shape A/S Copenhagen, Denmark) software was used for making the necessary tooth size measurements. Results: When the measurements were evaluated, it was determined that significant changes occurred between tooth sizes of individuals with different malocclusions. Generally, higher values were observed in mesiodistal and buccolingual tooth dimensions of class II individuals compared to other groups. There was no difference between the groups in the anterior ratio values, but when the overall ratio values were evaluated among the groups, a statistically significant difference was determined. Class II malocclusion group was found to have a significantly lower overall ratio of occurrence. Conclusion: Individuals with different malocclusions differ in tooth size.

Bolton Ratio of Different Angle’s Classifications in a School Children Sample of Erbil City

Aims of this study were to determine both the Bolton anterior and overall ratios in a representative sample of Erbil schoolchildren of Normal occlusion and Cl I, Cl II div I, div II, and Cl III malocclusion, also to find if there are any gender differences. Numerical data were obtained, comprised of 320 samples study casts of students with a mean age of 13–15 years selected from different schools in Erbil City. The casts were divided into 5 groups according to the type of malocclusion: Normal (n = 64), Cl I (n = 64), Class II div I (n = 64), Class II div II (n = 64), and Class III subjects (n = 64). The measurement of the greatest mesiodistal width of the teeth was performed using digital Vernier directly on the study casts, from the distal surface of the left first molar to the distal surface of the right first molar. The overall and anterior ratios between the maxillary and mandibular teeth were computed and evaluated using Bolton’s method. The results revealed that the mean anterior ratio (78.863) was higher and statistically signifi cantly different from anterior Bolton’s (77.2) and also the mean overall ratio was not statistically signifi cant different from Bolton’s ratio (91.3) (P = 0.239), with respect to the overall and anterior ratios among all the groups, statistically significant differences were found. Differences between genders were analyzed using a t-test. The results showed that there were no signifi cant differences between males and females. There were non-significant differences between the findings of the present study and those of Bolton’s study for overall ratio and anterior ratio, but among all five classifications, there was a significant difference of Erbil population not similar to Bolton ratio and there was no significant difference between males and females.

Hubungan antara diskrepansi ukuran gigi anterior rahang atas dan rahang bawah terhadap profil jaringan lunak wajah berdasarkan analisis BoltonThe correlation between maxillary and mandibular anterior size discrepancy and soft tissue facial profile based on Bolton analysis

Pendahuluan: Diskrepansi ukuran gigi dan profil wajah merupakan dua faktor yang membantu dalam proses penegakan diagnosis dan penentuan rencana perawatan ortodonti. Pengukuran diskrepansi ukuran gigi dapat dilakukan dengan analisis Bolton, analisis ini dapat menunjukkan rasio lebar mesiodistal antara gigi pada maksila dan gigi pada mandibula. Profil wajah dapat digunakan sebagai guideline dalam menentukan estetik wajah yang ingin dicapai setelah perawatan. Tipe profil wajah dapat diinterpretasi dari hasil fotografi ekstraoral, pada penelitian ini analisis Bolton yang dilakukan hanya meliputi rasio anterior saja. Penelitian ini bertujuan untuk menganalisis hubungan antara diskrepansi ukuran gigi rahang atas dengan ukuran gigi rahang bawah berdasarkan analisis Bolton terhadap profil jaringan lunak wajah pada mahasiswa Fakultas Kedokteran Gigi Universitas Padjadjaran. Metode: Penelitian analitik observasional diawali dengan pengambilan sampel dengan teknik purposive sampling dan didapatkan 50 orang sampel mahasiswa Fakultas Kedokteran Gigi angkatan 2016 kemudian dilakukan analisis rasio anterior Bolton pada model studi dan interpretasi hasil foto profil ekstraoral. Uji korelasi Pearson dilakukan untuk mengetahui korelasi dari kedua variabel tersebut. Hasil: Rata-rata anterior ratio dari 50 orang sampel sebesar 79,53% ±2,61 dengan profil wajah lurus sebanyak 33 orang (66%) dan profil wajah cembung sebanyak 17 orang (34%) dengan rata-rata derajat konveksitas 172,11°. Uji korelasi Pearson menghasilkan nilai p-value (0,896) yang lebih besar dari α=0,05. Tidak ada korelasi yang signifikan antara diskrepansi ukuran gigi dan profil wajah. Simpulan: Tidak terdapat hubungan antara diskrepansi ukuran gigi dan profil wajah.Kata kunci: Analisis Bolton, diskrepansi ukuran gigi, profil wajah. ABSTRACTIntroduction: Tooth size discrepancy and facial profile are two crucial factors for helping diagnosis and treatment planning of orthodontic treatment. Bolton analysis could measure tooth size discrepancy; and the analysis result shows the ratio of mesiodistal width between maxillary and mandibular teeth. The facial profile could be used as a guideline for aesthetic result in orthodontic treatment. The facial profile can be analysed from an extraoral profile photograph. In this research, we only calculate the anterior ratio of the sample. The purpose of this study was to determine the correlation between maxillary and mandibular anterior size discrepancy and soft tissue facial profile of the students of the Faculty of Dentistry Universitas Padjadjaran based on Bolton analysis. Methods: The research was conducted with observational analytic methods. The sampling method was conducted using the purposive sampling method, which resulted in 50 samples taken from students of the Faculty of Dentistry Universitas Padjadjaran batch 2016. Analysis of the sample’s anterior ratio was measured on the study cast with Bolton analysis and interpretation of the extraoral profile photograph. Both variables (tooth size discrepancy and facial profile type) were then analysed with Pearson’s correlation test to determine the correlation between the two variables. Results: The average anterior ratio from 50 samples was 79.53% ± 2.61, and the most common facial profile type was straight/orthognathic, which was found in 33 samples (66%) followed by convex in 17 samples (34%) with average facial convexity was 172.11°. The result of Pearson’s correlation test showed that the p-value was 0.896, which was higher than α = 0.05. There was no significant correlation between tooth size discrepancy and soft tissue facial profile. Conclusion: There is no correlation between tooth size discrepancy and soft tissue facial profile.Keywords: Bolton analysis, tooth size discrepancy, facial profile.

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

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.

Applicability of Bolton’s Analysis: A Study on Tibetan Community

Aim This study aimed to evaluate the anterior and overall ratios of Tibetan population residing at Mundgod and to compare the obtained ratios to the ratios available from Bolton’s study. Materials and Methods The study consists of randomly selected 120 samples of Tibetan population ranging in age from 15 to 25 years, residing at Mundgod, Karnataka (60 males and 60 females). After measuring the width of each tooth, overall and anterior ratios were measured using formula proposed by Bolton. Statistical Analysis Anterior and overall tooth ratios obtained from the study were compared to standard Bolton’s ratio by one-sample t-test. The differences between males and females were compared by independent samples t-test. Results The overall ratio was significantly lower for both males (P = 0.03) and females (P = 0.001) at 90.20 and 88.93, respectively, when compared to the Bolton’s value of 91.3, whereas anterior ratio for males (P = 0.001) was significantly higher at 77.9 when compared to Bolton’s value of 77.2. The combined values of males and females when compared to Bolton’s value, i.e., the combined overall ratio (P = 0.001) was significantly lower at 89.5 and the combined anterior ratio (P = 0.016) was significantly higher at 78.7. Conclusion In the present study, significant difference was observed between the overall and anterior ratios in Tibetan population as compared to the Bolton’s value. Therefore, Bolton’s original data cannot be applied for Tibetan population.

Bolton’s Tooth Size Discrepancy in Malaysian Orthodontic Patients: Are Occlusal Characteristics Such as Overjet, Overbite, Midline, and Crowding Related to Tooth Size Discrepancy in Specific Malocclusions and Ethnicities?

Introduction Tooth size, occlusal traits, and ethnicity are closely interrelated, and their impact on desirable orthodontic treatment outcome cannot be underestimated. This study was undertaken to assess the occlusal characteristics and ethnic variations in occlusion of Malaysian orthodontic patients and evaluate their correlation with Bolton’s tooth size discrepancy. Materials and Methods On 112 pretreatment study models of orthodontic patients, molar relationship, overjet, overbite, spacing, crowding, midline shift, and Bolton’s ratios were assessed. ANOVA, one-sample t-test, Chi-squared test, and Spearman’s rho correlation coefficient were used for statistical analysis. Results Significant difference between anterior ratio of our study and Bolton’s ideal values was found, for the entire study sample and Chinese ethnic group. Differences between races and malocclusion groups were not statistically significant (P > 0.05). Significant correlations were found as follows – in Angle’s Class I malocclusion between 1) anterior ratio and overbite, 2) overall ratio and maxillary crowding and spacing; in Angle’s Class II malocclusion between 1) anterior ratio and overjet and midline shift, 2) overall ratio and mandibular crowding; in Angle’s Class III malocclusion between 1) anterior ratio and mandibular crowding and both maxillary and mandibular spacing 2) overall ratio and mandibular crowding. Conclusions Significant differences in anterior ratio and Bolton’s ideal values for the Malaysian population were found, indicating variations in anterior tooth size as compared to Caucasians. Statistically significant correlations existed between Bolton’s ratios and occlusal traits. These findings can be applied clinically in diagnosis and treatment planning by keeping in mind the specific discrepancies that can occur in certain malocclusions and addressing them accordingly.

Tooth width Ratio in Crowding and Noncrowding dentition among patient Attending BSMMU

Crowding is a common presentation among thepatients seeking orthodontic treatment. The cause of crowding could be various such as mesiodistal tooth width discrepancy, boney discrepancy among the jaw, earlyloss of deciduous molar, different patterns of malocclusion, ethnic group, nutritional and developmental factor.Materials and Methods: One hundred cases were selected among which 31 were male and 69 were female, 70 cases had crowded dentition and 30 cases had non crowded dentition. Bolton’s Overall ratio and Anterior ratio were calculated for every case and comparison was done among crowded and non crowded dentitions.Result: Mean Overall ratio and mean anterior ratio were found to be 91.06% and 79.66% Neither Overall ratio nor Anterior ratio was significant for crowding and non crowding cases. On comparing for male and female, only anterior ratio was found to be significant in female in crowding and non crowding cases. Ban J Orthod & Dentofac Orthop, April 2014; Vol-4 (1-2), P.12-15

THE RELIABILITY OF THE BOLTON RATIO WHEN APPLIED TO THE INDONESIAN POPULATION

Objective: The objective of this study is to determine whether Bolton ratio can be applied clinically to the Indonesian population and to determine a more suitable Bolton ratio for the Indonesian population.Methods: This study was conducted on 120 readily available study models of treated cases comprising 37 males and 83 females. Two investigators separately measured the mesiodistal crown width of maxillary and mandibular tooth on each study model using sliding calipers. According to Bolton’s method, the overall and anterior ratios from each sample were calculated and the mean was generated. Using Student’s t-test with a 95% confidence interval, the investigators compared whether there is a significant difference between the ratio from Bolton’s samples and the ratio from the Indonesian samples.Results: The result of this study showed that, for Indonesian samples, the overall ratio is 89.7±2.05, while the anterior ratio is 76.4±2.76. Student’s t-test showed that there is a statistically significant difference (p<0.05) between the results of this study and that of Bolton’s study for both the anterior and overall ratios.Conclusion: It can be concluded that there is a difference between Indonesian population and Caucasian population in tooth size and Bolton ratio value. Therefore, original Bolton ratio value cannot be used as an accurate diagnostic tool for Indonesian population.

Determination of Bolton Norms for Indian Population Sample

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.