Research Article

Bolton tooth size discrepancy among different malocclusion groups

in two different ethnic groups of Nepalese population

Dr. Umesh Parajuli1, Dr. Alok Kumar Jaiswal2, Dr. Manish Bajracharya3, Dr. Manju Pandey4,
Dr. Sapna Laxmi Tuladhar5
1
Associate Professor, Department of Orthodontics, College of Dental Surgery, Gandaki Medical College
2
Associate Professor, Department of Orthodontics, College of Dental Surgery, M B Kedia, Birgunj Nepal
3
Associate Professor, Department of Orthodontics, National Academy of Medical Sciences, Bir Hospital
4
Lecturer, Department of Orthodontics, College of Dental Surgery, Gandaki Medical College
5
Associate Professor, Department of Prosthodontics, College of Dental Surgery, Gandaki Medical College

Corresponding author: Dr. Umesh Parajuli; Email: drumeshparajuli@gmail.com

ABSTRACT

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.

KEYWORDS: Bolton’s study, Ethnic variation, Tooth size discrepancies

INTRODUCTION
Tooth size discrepancy is the disproportion between Researchers have shown that there are tooth size
teeth sizes of same arch or between opposing arches discrepancies in different malocclusion groups.3,4
in the anterior segment or both anterior and posterior Araujo and Souki5 found that Class I and Class III
segment.1 In some cases during the finishing phase of patients had greater tooth size discrepancy than Class II
the treatment it is difficult to co-ordinate the maxillary patients with mandibular tooth size excess and smaller
and mandibular arches due to tooth size discrepancies. maxillary teeth in Class III malocclusion groups.5,6
Wayne Bolton in 1958 generated equation to determine Mahmoud NM et al.4 found Class II Div 1 to have more
the anterior and overall ratio for tooth size discrepancy tooth size materials in maxillary arch and Class II Div
between maxillary and mandibular arches from fifty-five 2 to have more tooth size material in mandibular arch.
dental casts with ideal occlusion.2 Some other studies done by Uysal T and Sari Z,7 Crosby

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Orthodontic Journal of Nepal, Vol. 11 No. 1 January - June 2021
Parajuli U, Jaiswal AK, Bajracharya M, Pandey M, Tuladhar SL : Bolton tooth size discrepancy among different malocclusion groups in two different ethnic groups of Nepalese population

DR and Alexander CG,8 Johe RS et al.9 and Smith SS et Age group 12-35 years; considering the most common
al.10 showed no differences in tooth size discrepancies age group visiting department of orthodontic18 3) All
in different malocclusion groups. set of permanent teeth should be erupted excluding
third molars. The exclusion criteria were 1) Individuals
Studies have shown that there is variation in tooth size with over-retained deciduous teeth 2) Individuals
ratios in different ethnic group.11,12 In contrary some with proximal caries, abnormal morphology of teeth,
other studies have shown no differences in tooth size missing teeth. 3) Individuals with history of orthodontic
ratio in various ethnic groups.10,13 Broadly classifying treatment. After the clinical examination alginate
Nepal is inhabited by three major ethnic groups based impressions of maxillary and mandibular arches were
on place of origin and language; Tibeto-Burman, Indo- made for individuals meeting the inclusion criteria.
Aryan and Indigenous.14 The major population groups of The impressions were poured with dental stone to
Gandaki Province of Nepal are Brahmins 21%, Magars make study models. The mesio-distal width of 12 teeth
19%, Chettris 13% and Gurungs 11%.15 These populations from first molar to first molar on both maxillary and
are grouped based on ethnic origin into Indo-Aryan and mandibular arches were measured with digital vernier
Tibeto-Burman. The Indo-Aryan includes Brahmins caliper with accuracy of 0.01mm by a single operator
and Chettris and Tibeto-Burman includes Magars and who is an orthodontist. To avoid examiner fatigue only
Gurungs.14, 16Tooth size discrepancies in different ethnic 10 study models were be measured in a day.
groups and different malocclusion groups have not been
studied in Nepalese population. This study attempts Bolton’s anterior and over all tooth size ratio was
to find out any tooth size discrepancies prevalent in calculated. The individuals were grouped according to
two different ethnic groups included in the study and Angle’s molar relations into Angle Class I, Class II and
different malocclusion groups. Class III.

MATERIALS AND METHOD Twenty percentages of the samples that is 40 study

This was a hospital-based cross-sectional study models were re-measured by same investigator after
conducted at College of Dental Surgery, Gandaki two weeks and intra-class coefficient correlation was
Medical College for a period of four months from May used to see for intra-examiner reliability. The data
2020 to Oct 2020 after obtaining ethical clearance from management was performed using SPSS software
institutional review board (Ref no: 022/2076/2077). (version 20; SPSS Inc., Chicago, IL, USA). Bolton’s
Sample size calculation was based on 80% power anterior and overall tooth size ratios were calculated.
and significance level of 5%17 and considering 0.75 as The distribution of individuals according to Angle’s
maximum tolerable error rate and based on standard molar relationship into Angles Class I, Class II and
deviation of 2.5. Class III was calculated. One sample t-test was used to
N=[Z +(1-ß)]2X SD2/L2=(1.96+0.84)2X2.52 =87.11 compare the tooth size discrepancies in Class I, Class
0.75x0.75 II and Class III malocclusion groups in Indo-Aryans and
Tibeto-Burmans with Bolton’s norms. The comparisons
Where, Z=Confidence interval (95%, CI=1.96), of tooth size discrepancies between two ethnic groups
ß=probability of type II error= 0.16 , Standard Deviation= was done with one sample t-test and were compared
2.5, L= tolerable error=0.75 and N=Sample size. The with Bolton’s study with one sample t-test. The
sample size came to be 87.11. The sample consisted difference in tooth size discrepancies between males
of 200 patients, 100 in each group. The patients visiting and females in the two ethnic groups was also seen
outpatient department of College of Dental Surgery, with one sample t-test. The mesio-distal tooth size of
Gandaki Medical College were screened after getting maxillary 12 and mandibular 12 teeth were compared
the informed consent. The inclusion criteria were 1) between the two ethnic groups with one sample t-test.
Individuals of specified ethnic origin Brahmins, Chettris, Correlation between tooth size discrepancies and
Magars and Gurungs of Nepalese origin which was angles malocclusion groups in Indo-Aryans and Tibeto-
supported with surname, place of origin and with no Burmans was seen with one way ANOVA. The results
inter-ethnic mixing with inter-caste marriage which was were considered significant at the 5% uncertainty level
assessed for two generations from history taking. 2) (p<0.05).

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Orthodontic Journal of Nepal, Vol. 11 No. 1 January - June 2021
Parajuli U, Jaiswal AK, Bajracharya M, Pandey M, Tuladhar SL : Bolton tooth size discrepancy among different malocclusion groups in two different ethnic groups of Nepalese population

RESULT significant differences in anterior ratio and overall ratio

Study models of 200 patients with average age of both ethnic groups when compared with the Bolton’s
17.77±5.11 years were analyzed in the study. Out of study (Table 2). There were no statistical significant
them 100 were Indo-Aryans and 100 were Tibeto- differences in the anterior and overall ratio amongst
Burmans. Ninety three (46.50%) were females and males and females of both ethnic groups but the males
107(53.50%) were males. The distribution of patients had higher anterior and overall ratios (Table 3).
according to Angles malocclusion was Class I 105
(52.50%), Class II 62 (31%) and Class III 33(16.50%). The mesio-distal tooth size was greater in Tibeto-
Intra-examiner reliability was seen with intra-class Burmans as compared to Indo-Aryans expect for
coefficient correlation, which showed the intra class maxillary right and left central incisors which was
correlation ranged from 95.1 to 99.6 suggesting greater in Indo-Aryans (Table 4). The mesio-distal
reliability in intra-examiner measurements. The width of maxillary right canine, first premolar ,second
anterior ratio and overall ratio in Indo-Aryans and premolar, maxillary left first premolar, second premolar,
Tibeto-Burmans in all the malocclusion groups were first molar, mandibular left canine, first premolar, first
greater than the Bolton’s study but was not statistically molar, mandibular right canine, first premolar and first
significant (Table 1).There was significant differences molar were significantly greater in Tibeto-Burmans as
in anterior ratio between Indo-Aryans 77.63±2.74% and compared to Indo-Aryans (Table 4). One way ANOVA
Tibeto-Burmans 78.51±2.76%, p-value=0.024 (Table 2). showed no correlation in the ratios between the Indo-
The overall ratio of Tibeto-Burmans 92.22±2.42% was Aryans and Tibeto-Burmans when compared with Class
slightly greater than the Indo-Aryans 92.19±2.30% with I, Class II and Class III malocclusion groups (Table 5).
no statistical significance (Table 2). There were no

Table 1.Comparison of tooth size discrepancies in Class I, II and III malocclusion groups in Indo-Aryans and
Tibeto-Burmans with Bolton’s study

Anterior ratio Overall ratio

Ethnic Angle’s Mean±SD Mean±SD
n p-value p-value
Groups Malocclusion Bolton’s Present Bolton’s
Present Study
Study Study Study
I 47 77.41±2.54 0.935 91.94±2.22 0.776
Indo-
II 41 77.93±2.44 0.768 92.42±2.22 0.621
Aryans
III 12 77.42±4.25 0.962 92.40±2.98 0.730
77.2±1.65 91.3±1.91
I 58 78.41±2.52 0.634 92.02±1.99 0.721
Tibeto-
II 21 78.16±2.15 0.667 91.93±2.43 0.802
Burmans
III 21 78.99±3.83 0.653 92.92±3.32 0.639

Table 2.Comparison of tooth size discrepancies between Indo-Aryans and Tibeto-Burmans and with Bolton’s study

Anterior ratio Overall ratio

Ethnic
Present Study Bolton’s Study p-value Present Study Bolton’s Study p-value
Groups
Mean±SD Mean±SD Mean±SD Mean±SD
Indo-
77.63±2.74 0.877 92.19±2.30 0.701
Aryans
77.2±1.65 91.3±1.91
Tibeto-
78.51±2.76 0.638 92.22±2.42 0.705
Burmans
p-value 0.024* 0.928
*Significant p<0.05

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Orthodontic Journal of Nepal, Vol. 11 No. 1 January - June 2021
Parajuli U, Jaiswal AK, Bajracharya M, Pandey M, Tuladhar SL : Bolton tooth size discrepancy among different malocclusion groups in two different ethnic groups of Nepalese population

Table 3.Comparison of tooth size discrepancies in males and females in Indo-Aryans and Tibeto-Burmans

Anterior ratio Overall ratio

Ethnic Groups Male Female p-value Male Female p-value
Mean±SD Mean±SD Mean±SD Mean±SD
Indo-Aryans
77.84±2.69 77.39±2.80 0.422 92.49±2.33 91.86±2.26 0.166
n=100
Tibeto-Burmans
78.95±2.72 77.97±2.75 0.079 92.56±2.52 91.81±2.24 0.121
n=100

Table 4. Comparison of mesio-distal tooth size between Indo-Aryans and Tibeto-Burmans values are presented as
mean±standard deviation

Indo- Aryans Tibeto-Burmans

Quadrant Tooth p-value
Mean±SD Mean±SD
11 8.90±0.54 8.84±0.64 0.448
12 7.22±0.64 7.34±0.59 0.168
13 7.99±0.45 8.13±0.46 0.034*
Maxillary right
14 7.16±0.46 7.52±0.52 0.001*
15 6.79±0.44 6.97±0.56 0.009*

16 10.18±0.51 10.31±0.59 0.085

21 8.89±0.54 8.84±0.64 0.235

22 7.12±0.58 7.28±0.65 0.064

23 7.93±0.46 8.06±0.46 0.058

Maxillary left
24 7.19±0.44 7.58±0.50 0.001*

25 6.74±0.46 6.96±0.53 0.002*

26 10.09±0.48 10.29±0.54 0.008*
31 5.56±0.35 5.58±0.38 0.635
32 6.15±0.42 6.24±0.46 0.158

33 6.99±0.42 7.22±0.46 0.001*

Mandibular left
34 7.32±0.49 7.50±0.50 0.009*

35 7.19±0.54 7.32±0.53 0.099

36 11.28±0.59 11.47±0.65 0.037*

41 5.54±0.36 5.58±0.39 0.448
42 6.13±0.39 6.23±0.45 0.099
43 6.92±0.44 7.18±0.44 0.001*
Mandibular right
44 7.27±0.56 7.43±0.49 0.032*
45 7.17±0.59 7.27±0.57 0.250
46 11.18±0.67 11.43±0.65 0.009*
*Significant p<0.05

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Parajuli U, Jaiswal AK, Bajracharya M, Pandey M, Tuladhar SL : Bolton tooth size discrepancy among different malocclusion groups in two different ethnic groups of Nepalese population

Table 5.Correlation between anterior ratio and overall ratio and Angle’s malocclusion groups in two ethnic groups

Class I Class II Class III

Ethnicity TSD Total p-value
Mean±SD Mean±SD Mean±SD

Indo-Aryans Anterior ratio 77.41±2.54 77.93±2.44 77.42±4.25 77.63±2.74 0.650

(n=100) Overall ratio 91.94±2.22 92.42±2.22 92.40±2.98 92.19±2.30 0.595

Tibeto-Burmans Anterior ratio 78.41±2.52 78.16±2.15 78.99±3.83 78.51±2.76 0.616

(n=100) Overall ratio 92.02±1.99 91.93±2.43 92.92±3.32 92.22±2.42 0.325

DISCUSSION Uysal and Sari7. This is also in accordance to study done

Tooth size a discrepancy is based on ethnicity.13 Our by Mishra et al.20 in Nepalese population who compared
study showed that there was significant greater anterior the tooth size discrepancies in normal occlusion, Class
ratio in Tibeto-Burmans 78.51±2.76% as compared to I malocclusion and Class II malocclusion groups. Our
Indo-Aryans 77.63±2.74%, p= 0.024. The overall ratio was study showed that there was no difference in both
greater in Tibeto-Burmans 92.22±2.42% as compared anterior and overall ratio as compared between males
to Indo-Aryans 92.19±2.30% but was not statistically and females (Table 3). This is in agreement with
significant. Similar results were seen in study done by the study done by Mishra et al.20 and Hong et al.23 in
Mulimani et al.,3 the Chinese ethnic group had greater Nepalese population, M.A Ismail et al.24 and Mahmound
anterior tooth size ratio 78.1±2.23% than the Malay and NM et al.4 in Sudanese population, Endo et al.25 in
Indian. The overall ratio amongst the Chinese, Malay Japanese population. This finding is in contrary to the
and Indian in the Malaysian orthodontic patients was study done in Nepalese population by Jaiswal A et al.26
comparable which is in agreement with the present They found the males have significantly higher anterior
study.3 The greater anterior ratio amongst the Tibeto- ratio as compared to females. This difference again
Burmans could be attributed to the greater number could be attributed to ethnic distribution in the sample
of patients with Class III malocclusion (n= 21, 21%) in size considered.
this ethnicity as compared to Indo-Aryans (n= 12,12%).
Strujic et al.19 and Mahmound NM et al.4 Sudanese in The Tibeto-Burmans in this study had greater mesio-
their study also showed there was increase in the ratio distal tooth dimension as compared to Indo-Aryans
amongst Class III malocclusion groups.4 except for the maxillary central incisors. The mesio-
distal width of maxillary right canine, first premolar,
The anterior and overall ratios of both the ethnic groups second premolar, maxillary left first premolar, second
as compared to Bolton’s norms was higher but showed premolar, first molar, mandibular left canine, first
no significant differences (Table 2). The finding for premolar, first molar, mandibular right canine, first
the overall ratio was consistent with a study done in premolar and first molar showed statistically greater
Nepalese population by Mishra et al.20 but the finding for value in Tibeto-Burmans as compared to Indo-Aryans
anterior ratio was contradicting. The anterior ratio in the (Table 4). The variation of tooth size with ethnic group is
study done by Mishra et al. showed significant greater in concordance with study done in Nepalese population
ratio as compared to Bolton’s norms. This difference by Shrestha RM,27 in Saudi Arabian patients by Togoo
could be attributed to the differences in ethnic inclusion RA et al.28
in samples of two studies.
The greater anterior ratio in Tibeto-Burmans in this study
In our study there were no significant differences indicates that this group of patients might need inter-
in anterior and overall ratio in between different proximal reduction of tooth size material in mandibular
malocclusion groups within the two ethnic groups anterior region in order to achieve optimal overjet,
when compared to the Bolton’s study but the ratios overbite and midline relationship. This consideration
were slightly higher than the Bolton’s study which is in during the diagnosis and treatment planning stage
accordance to the findings by Machado V et al.21 in their might help clinician achieve good treatment results.
systematic review and meta-analysis (Table 1). This is in
accordance to the study done by O’ Mahony et al.22 and

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Jaiswal AK, Shrestha GK, Tuladhar W, Singh B, Gupta R : Prevalence of malocclusion in Parsa district: A comparative study

CONCLUSION CONFLICTS OF INTEREST

There were no significant differences in anterior ratio No potential conflict of interest relevant to this article
and overall ratio in Indo-Aryans and Tibeto-Burmans was reported.
in different malocclusion groups as compared to
Bolton’s original ratio. The Tibeto-Burmans had higher ACKNOWLEDGEMENTS
anterior ratio as compared to Indo-Aryans. There were We would like to thank Dr. Ima Gurung for helping with
no significant differences in anterior and overall ratio collection and compilation of data in this study.
in between males and females. There were statistical
differences in mesio-distal tooth size as compared
between Indo-Aryans and Tibeto-Burmans. OJN

REFERENCES

1. Shaye R. Contemporary Orthodontics, 4th ed. J Dent Educ 2007;71:1599–600. https://doi.org/10.1002/j.0022-0337.2007.71.12.

tb04437.x.
2. Bolton WA. Disharmony in tooth size and its relation to the analysis and treatment of malocclusion. Angle Orthod 1958;28:113–30.
https://doi.org/10.1043/0003-3219(1958)028<0113:DITSAI>2.0.CO;2.
3. Mulimani PS, Azmi MIB, Jamali NR, Basir NNBM, Soe HHK. 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? APOS Trends Orthod 2018;8:36–43. https://doi.org/10.4103/apos.apos_104_17.
4. Mahmoud N, Eltahir H, Mageet A. Tooth size discrepancy among different malocclusion groups in a Sudanese sample. J Orthod Endod
2017;3:10. https://doi.org/ 10.21767/2469-2980.100044.
5. Araujo E, Souki M. Bolton anterior tooth size discrepancies among different malocclusion groups. Angle Orthod 2003;73:307–13.
https://doi.org/10.1043/0003-3219
6. Sperry TP, Worms FW, Isaacson RJ, Speidel TM. Tooth-size discrepancy in mandibular prognathism. Am J Orthod Dentofacial Orthop
1977;72:183–90. https://doi.org/10.1016/0002-9416(77)90059
7. Uysal T, Sari Z. Intermaxillary tooth size discrepancy and mesiodistal crown dimensions for a Turkish population. Am J Orthod
Dentofacial Orthop 2005;128:226–30. https://doi.org/10.1016/j.ajodo.2004.04.029.
8. Crosby DR, Alexander CG. The occurrence of tooth size discrepancies among different malocclusion groups. Am J Orthod Dentofacial
Orthop 1989;95:457–61. https://doi.org/10.1016/0889-5406(89)90408-3.
9. Johe RS, Steinhart T, Sado N, Greenberg B, Jing S. Intermaxillary tooth-size discrepancies in different sexes, malocclusion groups, and
ethnicities. Am J Orthod Dentofacial Orthop 2010;138:599–607. https://doi.org/10.1016/j.ajodo.2008.11.031.
10. Smith SS, Buschang PH, Watanabe E. Interarch tooth size relationships of 3 populations: “does Bolton’s analysis apply?” Am J Orthod
Dentofacial Orthop 2000;117:169–74. https://doi.org/10.1016/s0889-5406(00)70228-9.
11. Mirzakouchaki B, Shahrbaf S, Talebiyan R. Determining tooth size ratio in an Iranian-Azari population. J Contemp Dent Pract 2007;8:86–93.
12. Adeyemi AT, Bankole OO, Denloye OO. Tooth size ratios of Nigerian and the applicability of Bolton’s analysis. Odonto-Stomatol Trop Trop
Dent J 2010;33:5–10.
13. Rahman A, Othman SA. Comparison of tooth size discrepancy of three main ethnics in Malaysia with Bolton’s ratio. Sains Malays
2012;41:271–5.
14. Nepal - Caste and Ethnicity n.d. http://countrystudies.us/nepal/31.htm (accessed December 14, 2020).
15. NepalMap profile: Gandaki Province. NepalMap n.d. https://nepalmap.org (accessed December 14, 2020).
16. Gurung HB. Nepal, social demography and expressions. 2nd ed. Kathmandu: New ERA; 2001.
17. Shirazi S, Kachoei M, Shahvaghar-Asl N, Shirazi S, Sharghi R. Arch width changes in patients with class II division 1 malocclusion
treated with maxillary first premolar extraction and non-extraction method. J Clin Exp Dent 2016;8:e403.
18. Piya A, Shrestha VB, Acharya J, Khanal S, Bhattarai P. Pattern of distribution of malocclusion among patients seeking orthodontic
treatment at Dental College-Nepal Medical College. J Nep Dent Asso 2013;13:36–41.
19. Strujić M, Anić-Milošević S, Meštrović S, Šlaj M. Tooth size discrepancy in orthodontic patients among different malocclusion groups.
Eur J Orthod 2009;31:584–9.
20. Mishra RK, Kafle D, Gupta R. Analysis of Interarch Tooth Size Relationship in Nepalese Subjects with Normal Occlusion and
Malocclusions. Int J Dent 2019;2019:1-6.
21. Machado V,Botelho J,Mascarenhas P,Mendes JJ, Delgado A. A systematic review and meta-analysis on Bolton’s ratios: Normal
occlusion and malocclusion. J Orthod 2020;47:7-29.

12
Orthodontic Journal of Nepal, Vol. 11 No. 1 January - June 2021
 Jaiswal AK, Shrestha GK, Tuladhar W, Singh B, Gupta R : Prevalence of malocclusion in Parsa district: A comparative study

22. O’Mahony G, Millett DT, Barry MK, McIntyre GT, Cronin MS. Tooth size discrepancies in Irish orthodontic patients among different
malocclusion groups. Angle Orthod 2011;81:130–3.
23. Hong Q, Tan J, Koirala R, Lina Y, Shimizu T, Nakano K, et al. A study of Bolton’s and Pont’s analysis on permanent dentition of Nepalese.
J Hard Tissue Biol 2008;17:55–62.
24. Ismail MA, Abuaffan AH. Tooth size discrepancy among different malocclusion groups in Sudanese sample: Orthodontic Waves
2015;74 :37-41.
25. Endo T, Abe R, Kuroki H, Oka K, Shimooka S. Tooth size discrepancies among different malocclusions in a Japanese orthodontic
population. Angle Orthod 2008;78:994–9.
26. Jaiswal AK, Paudel KR. Applicability of Bolton’s tooth size ratio for Nepalese population. J Nepal Dent Assoc 2009;10:84–7.
27. Shrestha R. Measurement of mesio-distal tooth diameter of Nepalese permanent dentition. J Nep Dent Assoc 2005;7:55–63.
28. Togoo RA, Alqahtani WA, Abdullah EK, Alqahtani AA, AlShahrani I, Zakirulla M, et al. Comparison of mesiodistal tooth width in individuals
from three ethnic groups in Southern Saudi Arabia. Niger J Clin Pract 2019;22:553.

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