|FORENSIC ODONTOLOGY: ORIGINAL RESEARCH ARTICLE
|Year : 2021 | Volume
| Issue : 1 | Page : 77-81
Establishment of sexual dimorphism by odontometric analysis of permanent maxillary and mandibular canines
Gunduji Sireesha, P Ramaswamy, Ch Saikiran, M Swathi, B Mrudula Raju
Department of Oral Medicine and Radiology, St. Joseph Dental College and Hospital, Eluru, Andhra Pradesh, India
|Date of Submission||28-Jul-2020|
|Date of Decision||29-Oct-2020|
|Date of Acceptance||10-Jan-2021|
|Date of Web Publication||26-Mar-2021|
Dr. Gunduji Sireesha
Post Graduate, Department of Oral Medicine and Radiology, St. Joseph Dental College and Hospital, Eluru - 534 003, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: In forensic identification, gender estimation is one of the most important parameters. Being the main component of the masticatory apparatus of the skull, teeth are a good source of material for the civil and medico-legal purpose. Gender estimation using dental features is mainly based on the comparison of tooth dimensions. Aim: This study aims at investigating and analyzing the presence of sexual dimorphism in maxillary and mandibular canine using crown dimensions. Settings and Design: The study sample consisted of a total of 204 subjects. The greatest mesiodistal (MD), labiolingual (LL) diameter, and crown height (CH) of the maxillary and mandibular canines were recorded clinically on the subjects with the help of a Digital Vernier Caliper and tight divider. Statistical Analysis: The data sample was computed using SPSS statistical program, version 21. Discriminant analysis was used to find the dimorphism in canine measurements between males and females. Results: This study revealed that males showed greater mean CH and mesiodistal dimensions for mandibular canine teeth in comparison to females. Out of the four canines, the mesiodistal dimensions of right maxillary and mandibular canines and CH of maxillary left and mandibular right canines were significantly different in males compared to those in females. According to the study, the right mandibular canine and left maxillary canine show highly consistent results for sexual dimorphism. Conclusion: The findings support the usefulness of odontometric analysis of the canine teeth in gender estimation. Therefore, it can be used as an adjunct along with other procedures for gender estimation.
Keywords: Canine, forensic anthropology, forensic dentistry, sex determination and analysis
|How to cite this article:|
Sireesha G, Ramaswamy P, Saikiran C, Swathi M, Raju B M. Establishment of sexual dimorphism by odontometric analysis of permanent maxillary and mandibular canines. J Indian Acad Oral Med Radiol 2021;33:77-81
|How to cite this URL:|
Sireesha G, Ramaswamy P, Saikiran C, Swathi M, Raju B M. Establishment of sexual dimorphism by odontometric analysis of permanent maxillary and mandibular canines. J Indian Acad Oral Med Radiol [serial online] 2021 [cited 2021 Sep 19];33:77-81. Available from: https://www.jiaomr.in/text.asp?2021/33/1/77/312198
| Introduction|| |
In forensic identification, gender estimation is one of the most important parameters. Being the main component of the masticatory apparatus of the skull, teeth are a good source of material for the civil and medico-legal purpose. Gender estimation using dental features is mainly based on the comparison of tooth dimensions. Being the most useful objects in the field of anthropology and genetics, teeth finds its utility in odontologic and forensic investigations. Various anthropological methods used to estimate gender, age, height, and ethnicity, will give information of an individual, which will guide police authorities when investigating cases of missing persons.
Teeth show resistance to damage in terms of bacterial decomposition, fire and are extremely durable even at high temperatures when rest of the body is damaged beyond recognition which makes them a valuable tool in forensic investigation.
Sex determination, by using dental features is primarily based on the comparison of dimensions of tooth in males and females, or on the comparison of frequencies of nonmetric dental traits, like Carabelli's trait of upper molars. Mesiodistal and buccolingual diameters of the permanent tooth crown are the two most commonly used and researched features in determining sex on the basis of dental measurements.
For gender estimation in forensic anthropology, sexual dimorphism of teeth finds its significance, especially in cases where positive and definitive identification of the individual, parts or bones is not viable. Canines are the most stable teeth in the oral cavity because of labiolingual (LL) thickness of the crown and the anchorage of root in the alveolar process of the jaws. The crowns of the canine teeth are shaped in such a manner so that they can promote cleanliness. This quality of self-cleansing and efficient anchorage in the jaws tend to preserve these teeth throughout life. They are the less frequently extracted teeth and are usually less affected by periodontal disease. Canine teeth have also been reported to survive in air and hurricane disasters. Hence, canines are being considered the “KEY TEETH” for personal identification. Teeth measurements are the most reliable methods in forensic investigations due to its advantage of being quick or less time consuming, noninvasive, and easy to perform. Hence our studies investigate whether sexual dimorphism can be established by odontometric study of permanent maxillary and mandibular canine teeth.
With this background a study was carried out to investigate and analyze the presence of sexual dimorphism in maxillary and mandibular canine using crown dimensions and our objective is to clinically measure the mesiodistal, labiolingual dimensions and crown height (CH) of maxillary & mandibular canines in males and females to determine which canine shows more dimorphism.
| Materials and Methods|| |
The study was carried out at the department of Oral medicine and radiology, of a dental school in India after getting approval by the Institutional ethical committee, with ethical clearance number CEC/11/2/2018-19. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation and with the Helsinki Declaration of 1964 and later versions.
All the subjects were explained the need and importance of the study and an written informed consent from each subject was taken prior to their participation in the study. Subjects with healthy gingiva and periodontium and mild gingivitis were included in the study. Caries free canine teeth with normal occlusion (canine and molar relationship) were also included in the study. Subjects having any developmental anomaly, restoration on canine, crown or bridge, attrited or missing canine, people undergoing or have already undergone orthodontic treatment and with any history of trauma were excluded from the study.
A total of 212 subjects (106 males and 106 females) from Dental College and Hospital, Eluru were randomly selected between the age group of 18 and 30 years based on inclusion and exclusion criteria for the study. Power analysis behind the sample size 212 is done by using G-power analysis. As few patients could not participate in the study the sample size got reduced to 204 and the power of study was adjusted to 0.95. The greatest mesio-distal (MD), labio-lingual (LL) diameter, and CH of the maxillary and mandibular canines were recorded clinically on the subjects with the help of a Digital Vernier Caliper using tight divider, with both the pointed ends placed between the anatomical points, on the subjects and carefully transferring them between the jaws of vernier caliper [Figure 1], [Figure 2], [Figure 3], [Figure 4]. All the measurements were taken twice by a single examiner and if in case of any discrepancy, a mean of two values was noted.
|Figure 4: Measuring the maximum dimension by transferring the pointed ends of divider between the jaws of digital vernier calipers|
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All odontometric measurements of four canine teeth and their related parameters were entered into a Microsoft Excel spreadsheet with the corresponding age and gender of the subjects. The data sample was computed using SPSS statistical program, version 21. Significance is set as 0.05 (P = 0.05). Discriminant analysis was used to find the dimorphism in canine measurements between males and females.
| Results|| |
[Table 1] shows detailed description of each tooth selected for study such as a mean value and standard deviation and P value both for males and females separately. Males showed greater mean CH and mesiodistal dimensions for mandibular canine teeth in comparison to females. Statistical analysis of permanent maxillary and mandibular canines showed that the mesiodistal dimensions of right maxillary and mandibular canines and CH of maxillary left and mandibular right canines were significantly different in males compared to those in females.
|Table 1: Mean and Standard deviation values of Crown height, Mesiodistal width and Labiolingual width of Maxillary and Mandibular canines|
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In [Table 2], Wilks' lambda is used to test which measurement is more sexually dimorphic. Several stepwise discriminate function statistics have been used to develop formulas to determine sex accurately. The group centroids indicate the average discriminant scores for each sex.
|Table 2: Wilks' lambda is used to test which measurement is more dimorphic(*)|
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In [Table 3], discriminant function coefficients were used to calculate discriminant score. To assess the sex, tooth dimensions were multiplied with the respective raw or unstandardized coefficients and added to the constant. If the values obtained are greater than the sectioning point the individual was considered a male and if the values are less than the sectioning point the individual was considered female.
In [Table 4], using centroids the cut-off values are calculated as '0' (zero). It indicates that discriminant score above zero is identified as males and below zero is identified as females.
|Table 4: Using centroids the cut-off values is calculated as ‘0’ (zero). It indicates that discriminant score above zero is identified as males and below zero is identified as females|
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As shown in [Table 5], our study got 84.5% of original grouped cases correctly classified.
| Discussion|| |
Gender estimation is one of the important parameters in forensic identification. Teeth are extremely durable at high temperatures and provide resistance to damage. Sex determination by using dental features is primarily based upon the comparison of tooth dimensions in males and females. Canines are the most stable teeth in the oral cavity because of the labiolingual (LL) thickness of crown and root anchorage in the alveolar process of the jaws. Hence our study analyzes the presence of sexual dimorphism in maxillary and mandibular canine using crown dimensions.
In this study males showed greater mean mesiodistal dimensions for mandibular canines than females [Table 1], which is similar to a crosssectional study conducted by Sreedhar et al. on dimorphic mandibular canines in Moradabad population of western Uttar Pradesh. The following parameters such as intercanine width (ICW), right and left mandibular canine width (RCW, LCW), and right and left mandibular canine index (RMCI, LMCI) were determined in male and female casts separately.
Wilks' lambda was used to test which measurement is more sexually dimorphic [Table 2]. Several stepwise discriminant function statistics have been used to develop formulas to determine sex accurately. The group centroids indicate the average discriminant scores for each sex.
Discriminant function coefficients are used to calculate discriminant score. To assess the sex, tooth dimensions are multiplied with the respective unstandardized coefficients and added to the constant [Table 3]. If the values obtained were greater than the sectioning point the individual was considered a male and if the values were less than the sectioning point the individual was considered female. Using centroids the cut-off values are calculated as '0' (zero). It indicates that discriminant score above zero is identified as males and below zero is identified as females [Table 4].
According to our study the mean width of mandibular canine in males and females on right and left canines are (8.529, 8.219) and (16.4917, 8.3025), respectively. Mandibular left canine shows greater sexual dimorphism compared to right canine which is similar to the study conducted on Lebanese population in which the left canine was found to reveal more sexual dimorphism (9.9%) as compared with right canine (9.7%).
Similar results were also observed in a study conducted by Parikh et al. (2013) on maxillary and mandibular canines among sixty subjects (30 males, 30 females) of age group ranging from 16 to 25 years. The result derived was that males showed significantly greater mean dimensions of teeth than females. The most sensitive predictors of gender determination were the mandibular intercanine distance and the canine index.
In a study conducted by Omar and Azab on dental casts of 220 adults, sexual dimorphism was observed in both MD and LL diameters of both maxillary and mandibular canine teeth in a sample of Egyptian adult individuals which were similar to our study.
Ali Ahmed (2014) conducted a study in Iraq on mandibular canines of 200 subjects (100 males and 100 females) of age ranging from 17 and 23 years. The results were that the MD widths of the mandibular canines were non-significantly slightly larger in males than in females while the intercanine width was larger in males than females with a highly significant difference.
Khangura et al., (2011) conducted a study on permanent maxillary incisors and canines on 100 subjects (50 males and 50 females). They inferred that all mean values of MD dimensions of permanent maxillary incisors and canines in males were greater compared to females but only canines were found to be statistically significant for sexual dimorphism.
Limitations and future prospects
In our study, the accuracy rate is 84.5%. This study cannot be used as the final prospect for the gender identification process. CBCT evaluation of the teeth can be done in longitudinal and cross sectional views. Along with many other radiographic gender estimation methods, canine measurements using CBCT has good scope in the field of forensic odontology.
| Conclusion|| |
Our study revealed that males show larger mean dimensions of canines than females in the study group.
The findings of our study support the usefulness of odontometric analysis of the canine teeth in gender estimation.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]