Home About us Editorial board Ahead of print Current issue Archives Submit article Instructions Subscribe Search Contacts Login 
  • Users Online: 442
  • Home
  • Print this page
  • Email this page


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2014  |  Volume : 26  |  Issue : 3  |  Page : 287-292

Gender determination from the mesiodistal dimension of permanent maxillary incisors and canines: An odontometric study


1 Department of Oral Medicine and Radiology, Rama Dental College Hospital and Research Centre, Kanpur, Uttar Pradesh, India
2 Department of Dental Surgery, Ranchi Institute of Neuro-Psychiatry and Allied Sciences, Ranchi, Jharkhand, India
3 Department of Oral Medicine and Radiology, Rishiraj College of Dental Science and Research Centre, Bhopal, Madhya Pradesh, India
4 Department of Oral Medicine and Radiology, Teerthankar Mahaveer Dental College Hospital and Research Centre, Moradabad, Uttar Pradesh, India

Date of Submission25-Jul-2014
Date of Acceptance11-Nov-2014
Date of Web Publication19-Nov-2014

Correspondence Address:
Rahul Srivastava
783/4 W-1, Saket Nagar, Juhi-2, Kanpur - 208 014, Uttar Pradesh
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0972-1363.145007

Rights and Permissions
   Abstract 

Introduction: Gender determination is crucial for identification, as the number of possible matches is reduced by 50%. The inert, mineralized structures of teeth resist post-mortem degradation and survive deliberate, accidental or natural change, better than any other skeletal structure. Tooth size measurements based on odontometric investigations in a specific population can be used in gender determination. Aims and Objectives: To evaluate and estimate the accuracy of using permanent maxillary incisors and canines for gender determination. Settings and Design: The undergraduate students of a dental college, meeting the inclusion criteria, were selected. After short listing the undergraduate students through the convenience sampling technique, a total of 300 subjects were purposively selected. Materials and Methods: The study was conducted on 300 subjects (150 males and 150 females), the mesiodistal dimensions of the maxillary anterior teeth were taken with the help of a digital vernier calliper and manual divider, with a sharp fine tip. Statistical Analysis: The collected data was subjected to statistical analysis. The data was subsequently processed and analyzed using the SPSS software package version 17. Results: The mesiodistal dimensions of the right and left maxillary canines and central incisors were significantly different (i.e., greater) in males as compared to females. Conclusion: The results of the present study showed that the maxillary central incisors and canines revealed a statistically highly significant sexual dimorphism and could be used as an adjunct for the determination of gender in individuals, as well as in groups, such as, in mass disasters or archaeological sites.

Keywords: Gender determination, odontometric analysis, sexual dimorphism


How to cite this article:
Srivastava R, Jyoti B, Jha P, Gupta M, Devi P, Jayaram R. Gender determination from the mesiodistal dimension of permanent maxillary incisors and canines: An odontometric study . J Indian Acad Oral Med Radiol 2014;26:287-92

How to cite this URL:
Srivastava R, Jyoti B, Jha P, Gupta M, Devi P, Jayaram R. Gender determination from the mesiodistal dimension of permanent maxillary incisors and canines: An odontometric study . J Indian Acad Oral Med Radiol [serial online] 2014 [cited 2019 Nov 21];26:287-92. Available from: http://www.jiaomr.in/text.asp?2014/26/3/287/145007


   Introduction Top


Forensic odontology or forensic dentistry, as defined by Keiser-Neilson in 1970, is 'that branch of forensic medicine, which in the interest of justice deals with the proper handling and examination of dental evidence, with proper evaluation and presentation of the dental findings'. Teeth can persist long after other skeletal structures have succumbed to organic decay or destruction by elements, such as fire. Being the most indestructible part of the body and exhibiting the least turnover of natural structure, they not only survive death, but also remain relatively unchanged for many years. [1],[2]

The first step for a trained forensic odontologist is to identify the gender from whatever human dental remains are presented as a specimen. The accuracy of sex differentiation by using post-mortem radiographs and/or specimens of the cranium, long-bone dimensions, pelvic structures, and so on, ranges from 96 to 100%. However, in more severe cases of devastation and body fragmentation or decomposition, dental identification is the most commonly used biometric methods for human identification. [3] Sexual dimorphism refers to the differences in size, stature, and appearance between males and females. This can be applied to dental identification also, because no two mouths are alike. [4] The existence of sexual dimorphism in permanent teeth is a known phenomenon, as observed in several investigations. This, therefore, has a great significance in forensic medicine. [5] Teeth may be used for differentiating sex by measuring their mesiodistal and buccolingual dimensions. Using teeth for determination of sex plays a pivotal role in young individuals where the skeletal secondary sexual characters have not yet developed. [6] The present study was undertaken to investigate the presence of sexual dimorphism in the mesiodistal dimension of permanent maxillary incisors and canines, as also its significance in the determination of sex in the north Indian population.


   Materials and Methods Top


This cross-sectional study was conducted in the Department of Oral Medicine and Radiology. The study was conducted on 300 undergraduate students (150 males and 150 females), in the age group of 20-30 years, selected from a dental college (located in North India). To detect a significant 10% difference between the two groups by using the chi-square test, based on α = 0.05 and 80% power, a total of 288 subjects were required in the two groups. With the estimation of the observed correlation among the anterior teeth to be 0.1, the calculated number was increased to 300. For the present study, undergraduate students of the dental college, meeting the inclusion criteria were included in the study. The subjects were selected using the convenience sampling technique. A total of 300 subjects were purposively selected after obtaining the participation consent of the subjects and permission from the Ethical Committee of the institute.

Inclusion criteria

The inclusion criteria were: Morphologically normal permanent teeth of the maxillary and mandibular jaws, intact mesiodistal diameter of the crown of the permanent teeth, teeth with no gross dental abnormalities, teeth with no apparent loss of tooth substance due to attrition or restorations affecting the mesiodistal diameter of the crown, healthy state of gingiva and periodontium, and teeth with no history of previous orthodontic treatment or proximal stripping.

Exclusion criteria

The exclusion criteria were: Students above the age of 30, presence of any deciduous teeth, congenitally missing teeth in any of the segments, subjects who had already received restorative treatment other than Class I occlusal restoration, clinically evident interproximal dental caries, fracture or fixed prosthesis (crown or bridge), subjects with a history of any type of orthodontic treatment, alteration in the number or shape of the teeth, and gingival and periodontal diseases.

The greatest mesiodistal dimension of the crown from the anatomic mesial contact point to the anatomic distal contact point of each tooth was measured with the help of a calibrated digital vernier calliper, accurate to 0.01mm. The digital vernier calliper was held parallel to the occlusal plane and the measurement was taken [Figure 1]. In cases of inaccessible areas, the measurement was taken with the help of a manual divider having sharp fine tips. The tips of the divider were placed over the greatest mesiodistal dimension of the tooth for measurement and the divider distance was then measured with the same digital vernier calliper [Figure 2]. To reduce the interobserver error, the following steps were taken:
Figure 1: Digital vernier calliper being held parallel to the occlusal plane and measurement being taken

Click here to view
Figure 2: Tips of the divider being placed over the greatest mesiodistal dimension of the tooth

Click here to view


  1. Each measurement was taken thrice
  2. All measurements were performed by a single operator


Statistical analysis

The collected data was subjected to statistical analysis. The data was subsequently processed and analyzed using the SPSS software package version 17. For determination of the size of the teeth, the range, mean, and standard deviation were calculated. A two sample t-test as well as Stepwise Discriminant Function Analysis was performed.


   Results Top


[Table 1] shows the mean value, standard deviation, and P-value of the maxillary incisors and canines for the subjects included in this study (males and females). The mesiodistal dimension of the maxillary incisors and canines was greater in males than females. The mesiodistal dimensions of the right and left maxillary canines and central incisors were significantly different in males when compared to females.
Table 1: Mean and standard deviation

Click here to view


The discriminant score was calculated with the help of function coefficients. For the assessment of the sex, both dimensions were multiplied with unstandardized coefficients. The obtained finding was added to the constant with the help of the following formula:

y = a + b (p1) + b (M2)

a = constant of function between the right and left maxillary central incisors and canines.

b = unstandardized coefficient of that specific tooth.

The canonical discriminant function coefficient is shown in [Table 2]. On measurement of the accuracy level for sex determination by using the right maxillary central incisor (11) separately, it was found that 62.0% males and 58.7% females were classified accurately. By using the left maxillary central incisor (21) it was found that 62.7% males and 58.0% females were correctly classified [Table 3] and [Table 4]. The accuracy level for sex determination, using the right and left maxillary canines was also measured separately and it was found that 62% males and 57.7% females were accurately classified by using the right maxillary canine (13). About 59.8% males and 55.3% females were accurately classified by using the left maxillary canine (23) [Table 5] and [Table 6]. The measurements shown in [Table 7] represent the accuracy level of sex determination by using the right and left maxillary central incisors and canines, which reveal that 62% males and 58.7% females were classified accurately. The range of the measured mesiodistal width of the maxillary central incisors and canines (including both sides, i.e., right and left) for both genders was analyzed. This range represents the sexual dimorphism that is shown in [Table 8]. The percentage of dimorphism can be defined as the percentage by which the tooth size of males exceeds that of females. The percentage of dimorphism for each tooth was calculated with the help of the following formula:
Table 2: Canonical discriminant function coefficient

Click here to view
Table 3: Accuracy of determination of gender using tooth 11

Click here to view
Table 4: Accuracy of determination of gender using teeth 21

Click here to view
Table 5: Accuracy of determination of gender using tooth 13

Click here to view
Table 6: Accuracy of determination of gender using tooth 23

Click here to view
Table 7: Accuracy of determination of gender using teeth 11, 13, 21, and 23

Click here to view
Table 8: Percentage of dimorphism

Click here to view


Percentage of dimorphism = {(X m / X f ) - 1} × 100

X m = Mean dimension of the male tooth

X f = Mean dimension of the female tooth


   Discussion Top


The variety and uniqueness of the teeth, number, and morphology in each individual, is a fact that increases its importance as an identifying element. [7] Teeth are known to be unique structures made of the most enduring mineralized tissues in the human body. As such, teeth are resistant to mechanical, chemical, physical, and thermal types of destruction. Therefore, teeth are very important elements in the identification of skeletal remains, especially in cases when, due to the poor preservation of skeletal remains, identification is not possible by the standard methods. [8]

Gender identification with the help of dental features can be grouped into non-metric and metric methods. Non-metric features are based on the presence or absence of a particular morphological feature. Identification of a population group or ethnicity can be done using the non-metric features of the crown and root, such as, upper incisor shoveling, cusp of Carabelli, hypocone, and protostylid. [9] The metric features are based on tooth measurements. The use of the metric approach in gender estimation is more structured, less subjective, and furthermore, it can be repeated to validate the obtained results. [10] The buccolingual and mesiodistal tooth dimensions may be used for determining the sex, based on the differences in tooth size and tooth proportions. [11] To determine the sex on the basis of tooth dimensions, the mesiodistal and buccolingual diameters of the permanent tooth crown are most commonly used and researched. [8] In this study, the mesiodistal dimensions of the teeth were measured directly in the subjects by a single operator and each measurement was taken thrice. Only the mesiodistal width of the teeth was evaluated for sexual dimorphism.

There are differences in the odontometric features in different populations, and even within the same population (in the historical and evolutional context). Therefore, determination of specific population values in order to make personal identification possible can be done on the basis of tooth measurements. [8] This study was conducted to evaluate the mesiodistal dimension of the maxillary incisors and canines of the north Indian population for males and females. Determination of sex using this method is relatively quick, easy, and inexpensive, compared to other costly, time-consuming, and technique-sensitive methods. Furthermore, it has a high utility in identifying subjects from fragmented jaws and dental remains. [3]

A study was conducted by Khan et al., to establish the nominative data on the mesiodistal crown dimensions of permanent teeth among the Bangladeshi population. The results from this study showed that males had significantly larger dimensions (than females) of maxillary central incisors and mandibular second premolars. In both sexes, the maxillary lateral incisors showed the greatest variability in the mesiodistal crown dimension, and the maxillary canines, the least. [12] However, in the present study, the maxillary incisors and canines showed that the mesiodistal dimensions of the right and left maxillary canines and central incisors were significantly different in males compared to females.

Singh et al., conducted a study to establish the normative data of the mesiodistal crown dimensions of permanent teeth in Punjabis, a population from the state of Northern India. The study was conducted on 110 individuals, of whom 40 were males and 70 were females, in the age range of 12-18 years. The results revealed the mesiodistal crown dimensions of the teeth of males to be more than that of females. Furthermore, the ratio of the mesiodistal crown dimension of the maxillary lateral incisors to the maxillary central incisors was 80% in females and 78% in males, and the total arch length in males was 117.77 mm in the maxilla and 111.60 mm in the mandible, while in females, the figures were 113.98 mm in the maxilla and 107.10 mm in the mandible. According to Dunn and Dobzhansky, as humans inhabit different parts of the world, they are exposed to different environments, and each population has a different set of teeth characteristics, and hence, are not alike. [13] Variations in tooth sizes between genders and among different racial and ethnic groups have been reported by several authors such as Richardson and Malhotra, Moyers et al., Moorrees et al., Santoro et al., Bishara et al., Singh and Goyal. [14] Results obtained from the present study showed that the mesiodistal dimension of male dentition was greater than that of females, which was in accordance with the previous studies. However, in the present study the mesiodistal dimension of the maxillary incisors and canines were significantly greater in males than females.

A study conducted by Hashim and Murshi on Saudi males and females in the age group of 13-20 years, to determine the teeth in human dentition with the highest likelihood of dimorphism, had found that only the canines in both the jaws exhibited a significant sexual difference, while the other teeth did not. In continuation of the same study, they also determined that there was no statistically significant difference between the left and right sides, suggesting that the measurements of the teeth on one side could be truly representative when the corresponding measurements on other side were unobtainable. [15]

Olayinka conducted a study to compare the mesiodistal and buccolingual crown dimensions of a group of Nigerian children to a matched British population sample. Results obtained from this study concluded that the mesiodistal crown dimensions of the Nigerian samples were significantly larger than their British counterparts. With the exception of the mandibular central incisors and maxillary canines, there were no significant differences in the buccolingual crown dimensions between the two populations. In the present study, a statistically significant dimorphism was shown by the permanent maxillary central incisors and canines. [16] Sexual dimorphism has been explained through the following theories:

  • Moss suggested that because of the longer period of amelogenesis there is a greater thickness of enamel in males compared to females, leading to a difference in dimensions.
  • Sex chromosomes are also responsible for the different effects on the tooth size. Compared to the 'X' chromosome, the 'Y' chromosome influences the timing and rate of body development, thus producing slower male maturation.
  • Dimorphism may be due to a biological variation, which is a characteristic of life and is attributed to family, genetics, and environmental factors. [17],[18]



   Conclusion Top


Sex determination using teeth is an inexpensive and easy method of gender identification from fragmented jaws and dental remains. The results of the present study revealed that maxillary central incisors and canines showed statistically highly significant sexual dimorphism and could be used as adjuncts for the determination of gender in individuals, as well as in groups, such as in mass disasters and archaeological sites.

 
   References Top

1.Leung CK. Forensic odontology. Hong Kong Med Diary Dent Bull 2008;13:16-20.  Back to cited text no. 1
    
2.Jurel SK. Role of dentist in forensic investigations. J Forensic Res 2012;3:148.  Back to cited text no. 2
    
3.Grover M, Bai RG, Ram T, Puri PM, Ghodke KR. An odontologist's key to sex determination: Study analysis of mandibular canine teeth in south Indian population. J Orofac Res 2013;3:157-60.  Back to cited text no. 3
    
4.Vishwakarma N, Guha R. A study of sexual dimorphism in permanent mandibular canines and its implications in forensic investigations. Nepal Med Coll J 2011;13:96-9.  Back to cited text no. 4
    
5.Galdames IS, López MC, Farías BL, Marchant CS, Muñoz ST, Rojas PG, et al. Sexual dimorphism in mesiodistal and bucolingual tooth dimensions in Chilean people. Int J Morphol 2008;26:609-14.  Back to cited text no. 5
    
6.Hemanth M, Vidya M, Shetty N, Karkera BV. Sex determination using dental tissue. Medico-Legal Update 2008;8:7-12.  Back to cited text no. 6
    
7.Astete JC, San Pedro VJ, Suazo GI. Sexual dimorphism in the tooth dimensions of Spanish and Chilean peoples. Int J Odontostomat 2009;3:47-50.  Back to cited text no. 7
    
8.Vodanoviæ M, Demo Ž, Njemirovskij V, Keros J, Brkiæ H. Odontometrics: A useful method for sex determination in an archaeological skeletal population? J Archaeol Sci 2007;34:905-13.  Back to cited text no. 8
    
9.Rajendran R, Sivapathasundharam B. Forensic odontology. In: Rajendran R, editor. Shafer's Textbook of Oral Pathology. 6 th ed. New Delhi: Elsevier India; 2009. p. 880-2.  Back to cited text no. 9
    
10.Bidmos MA, Gibbon VE, Štrkalj G. Recent advances in sex identification of human skeletal remains in South Africa. S Afr J Sci 2010;106:238. Available from: http://www.sajs.co.za/sites/default/files/publications/pdf/238-3116-4-PB.pdf  Back to cited text no. 10
    
11.Acharya AB, Mainali S. Sex discrimination potential of buccolingual and mesiodistal tooth dimensions. J Forensic Sci 2008;53:790-2.  Back to cited text no. 11
    
12.Khan SH, Hassan GS, Rafique T, Hasan MN, Russell MS. Mesiodistal crown dimensions of permanent teeth in Bangladeshi population. Bangabandhu Sheikh Mujib Medical University Journal 2011;4:81-7.  Back to cited text no. 12
    
13.Singh SP, Goyal A. Mesiodistal crown dimensions of the permanent dentition in North Indian children. J Indian Soc Pedod Prev Dent 2006;24:192-6.  Back to cited text no. 13
[PUBMED]  Medknow Journal  
14.Ajayi EO, Ajayi YO, Oboro HO, Chukwumah NM. Mesiodistal crown dimensions of the permanent dentition in a Nigerian population. Dental Anthropol 2010;23:57-60.  Back to cited text no. 14
    
15.Hashim HA, Murshid ZA. Mesiodistal tooth width. A comparison between Saudi males and females. Part 1. Egypt Dent J 1993;39:343-6.  Back to cited text no. 15
    
16.Otuyemi OD, Noar JH. A comparison of crown size dimensions of the permanent teeth in a Nigerian and a British population. Eur J Orthod 1996;18:623-8.  Back to cited text no. 16
    
17.Rani RM, Mahima VG, Patil K. Bucco-lingual dimension of teeth - An aid in sex determination. J Forensic Dent Sci 2009;1:88-92.  Back to cited text no. 17
    
18.Aggarwal B, Parihar KS, Gorea RK, Kaushal S. Sexual dimorphism in bucco-lingual diameter of mandibular canines in Punjabi population. J Indo Pac Acad Forensic Odontol 2010;1:16-9.  Back to cited text no. 18
    


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

   Abstract Introduction Materials and Me... Results Discussion Conclusion Article Figures Article Tables
  In this article
 References

 Article Access Statistics
    Viewed2065    
    Printed33    
    Emailed1    
    PDF Downloaded469    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]