Applicability of Digital Radiography in Identifying Gender through Morphometric Evaluation of the Mandibular RamusABSTRACT
Objective: To use digital radiographs for the morphometric evaluation of the mandibular ramus in gender identification.
Material and Methods: For the current cross-sectional investigation, 100 randomly selected panoramic images of patients were included. The sample selection was based on purposive sampling. At two-day intervals, a trained dental radiologist evaluated the mandibular ramus morphometrically (minimum and maximum ramus breadths, projective height of the ramus, condylar height, coronoid height, gonial angle, and bigonial width). The mean of the two measurements was used. The data were analyzed using discriminant function analysis and an independent t-test, with p<0.05 as the significance level.
Results: Among participants, 46% were men and 54% were women. Males were discovered to have a significantly greater mean maximum ramus height and projected maximum ramus height, whereas females were noted to have a slightly higher maximum ramus breadth. The overall accuracy of using the mandibular ramus to determine sex was 76%; however, the accuracy for identifying males and females was 78.1% and 74.1%, respectively.
Conclusion: The mandibular ramus is resistant to injury and disintegration processes; it can be used as a useful tool in gender assessment.
Keywords:
Gender Identity; Mandible; Radiography.
Introduction
Forensic odontology, a subspecialty of dentistry, uses dental evidence to address problems related to human identity [1]. Identification of human skeletal remains is considered the initial step in forensic investigations [2]. In almost every bone, sexual dimorphism is present. The most important bones are the cranium and the pelvis. Additionally, skeletal characteristics, nutrition, diet, disease, climate, and socioenvironmental factors influence mandibular sexual dimorphism [1]. One crucial aspect of medicolegal practice is the chronological assessment of age and gender. Age-related changes can be observed in the hard and soft tissues of the teeth. After a long time of burial, the facial bones are typically the only remnants that survive because of their exceptional fire resistance. As a result, forensic odontology has become increasingly significant as a method for identifying skeletal and dental remains [3].
Determining an individual's sex is a crucial component of forensic practice and medicolegal purposes. The mandible can be utilised to discriminate between genders and ethnic groupings. This is because the duration, growth rates, and phases of mandibular development vary significantly between the sexes. Gonial angle alteration may be influenced by variables other than age and tooth loss [4]. For the purpose of determining sex, measurements of the mandibular ramus and angle from a dry adult mandible can be utilised [3]. When the complete adult skeleton is available for study, the gender can be ascertained with 100% accuracy. However, it is impossible to determine a person's sex with 100% certainty in mass disaster situations, since bones are typically found in fragments. The pelvis and skull bones are used to determine sex in these circumstances. After the pelvis, the skull is the most dimorphic and easily identifiable part of the skeleton (for gender determination), with accuracy as high as 92%. This results from variations in the growth and maturation rates of skeletal bones. In general, male bones are bigger and stronger than those of females. The mandible is susceptible to the teenage growth spurt and is the last bone in the skull to stop growing [3]. It develops a far more resilient and well-preserved bone than many other bones because of the dense coating of compact bone that surrounds it. It is possible to distinguish between the sexes using the mandibular ramus [5].
In everyday dental practice, extra-oral digital dental radiography is becoming increasingly common. Digital radiography has become a valuable tool in forensic anthropology due to its simplicity in storing and generating images when needed. Several radiographic pictures, such as digital imaging, lateral cephalograms, panoramic radiographs, and lateral oblique X-rays, are useful in determining age and gender. The morphology and metric aspects of the skull provide information that can be used to determine the sex of an unknown person [5]. A radiograph is a non-invasive technique that can be used on live or deceased people. Digital panoramic radiography has been shown to provide anatomic dimensions accurately, and OPG has proven to be a useful tool in forensic research [6]. A comprehensive view of the maxillofacial complex can often be obtained with an OPG. Digital panoramic images offer several benefits, including wide coverage, a low radiation dose to patients, and quick image acquisition time [3]. Because they are less likely to be overlaid, panoramic radiographs are appropriate for linear vertical measurements of the mandibular ramus and condyle [7].
The objective of the present research was to evaluate the morphometric measurements on digital OPG for the precision and dependability of the mandibular ramus and gonial angle in gender discrimination.
Material and Methods
Study Design and Ethical Clearance
The current cross-sectional research was done in the Oral Medicine and Radiology Department. Before the commencement of the trial, the institutional ethical committee granted clearance under Ref No. SDCH/ETHI/S/08-2023-24, and each participant provided written informed consent.
Sample Size and Population
The sample selection was based on purposive sampling and gender inclusion was based on random selection of 100 participants in accordance to Saloni et al. [3], and Shrestha et al. [8]. One hundred randomly selected panoramic images [9] of patients visiting the OPD, captured for various diagnostic purposes aged 25 to 55 of both gender were chosen from Oral Medicine and Radiology outpatient departments.
The following inclusion criteria were used: radiographs taken without magnification errors; high‑quality panoramic radiographs free of distortion and artifacts; no missing teeth; and absence of any pathologies. Exclusion criteria were: individuals with systemic and endocrine problems, individuals who have previously experienced maxillofacial trauma or surgery, temporomandibular joint problems, individuals with syndromes or congenital maxillofacial abnormalities, women who are pregnant, and radiographs that are poorly visible.
The Carestream CS8000C digital OPG system (Kodak India Pvt Ltd, Hyderabad, India) was used to perform digital panoramic radiography on participants who met the inclusion and exclusion criteria after a clinical examination. The exposure variables used were standard (73 kVp, 12 mA, 13.9 s), as advised by the manufacturer. Before performing an OPG, a 2 cm, 20-gauge orthodontic metallic wire was positioned vertically in the pre-tragus region to account for vertical magnification. A single trained dental radiologist performed the independent morphometric analysis of the mandibular ramus twice at a 2-day interval. The mean of the two measurements was used. The parameters that were measured were the minimum and maximum ramus breadths, the projective height of the ramus, the coronoid height, the gonial angle, and the bigonial width. The parameters were defined as:
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A) Maximum ramus breadth: The separation along a line that runs from the angle of the jaw to the most posterior point on the condyle and the mandibular ramus.
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B) Minimum ramus breadth: Lowest anterior-posterior diameter of ramus.
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C) Coronoid Height: Projective space between the coronoid and the lower wall of the bone.
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D) Condylar/maximum ramus height: Height of the ramus measured from the tubercle, or the most projecting part of the inferior border of the ramus, to the most superior point on the mandibular condyle.
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E) Projective ramus height: Ramus projective height measured from the lower edge of the bone to the highest point of the mandibular condyle.
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F) Gonial angle: These were measured by finding the junction of two lines that were digitally traced and tangential to the posterior margins of the ramus and condyle, as well as the lower border of the mandibular body and the most inferior points at the angle.
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G) Bigonial width: the space between the two gonia.
Data Analysis
Using SPSS Software version 23 (IBM Corp., Chicago, IL, USA), the gathered data were tabulated and examined. The tests used were the discriminant function analysis and the independent t-test, with p<0.05 as the significance level.
Results
In the present study, 46 (46%) were male, and 54 (54%) were female. It was found that males had significantly higher mean ramus breadth, ramus height, coronoid height, and bigonial breadth than females (p < 0.01). Table 1 displays non-significant results for minimum and maximum ramus breadth and gonial angle, but significantly higher results (p<0.01) for males for maximum ramus height, coronoid height, projective ramus height, and bigonial width. In the present study, 4 of 7 parameters showed significant results for gender identification.
Using the canonical discriminant function coefficient and constant value derived from the mandibular ramus measurements, the accuracy of gender determination was determined. A sectioning point of 0.464 was determined. If the value of the discriminant function is close to 0.478, it indicates a high probability of being male; if it is close to - 0.464, it indicates a high probability of being female (Table 2).
The overall accuracy of using the mandibular ramus to determine sex was 76%; however, the accuracy for identifying males and females was 78.2% and 74.1%, respectively (Table 3).
Discussion
Measurements and morphology-based techniques are reliable and useful for determining sex from a skull; however, sex identification based on morphological features is subjective and prone to error [10]. The pelvis, skull, thorax, femur, vertebrae, and scapula are the bones most frequently examined to determine a person's sex [11].
Due to two factors, the mandibles were utilised to determine sex during mass disasters: first, there don't seem to be many criteria using this element, and second, this bone is frequently recovered mostly undamaged. The greatest chance of developing sexual dimorphism is in the mandibular region, where bone remodelling takes place. The biggest sexually dimorphic morphological changes occur in the ramus and condyle due to their constant remodelling and size variations during growth [3]. Because the mandibular ramus grows at distinct rates, lengths of time, and stages of development depending on gender, it is thought to distinguish between the sexes [12]. The mandibular ramus is thought to distinguish between genders based on variations in developmental stage, growth length, and growth rate.
The goal of the current study was to assess the validity and consistency of gonial angle and mandibular ramus morphometric measurements in gender discrimination. Discriminant functional analysis was used in this investigation to examine mandibular ramus measurements. Male and female gender differences show that ramus exhibits good sexual dimorphism. In general, gender can be reliably determined once the relevant bone has fully developed, which supports selecting the age group 25 to 55 years for this investigation.
Digital measurements are accurate enough for clinical usage, according to Schulze et al. [13], and the most dependable readings were obtained for linear objects in the horizontal plane. Our findings agreed with those of Damera et al. [10]. This investigation revealed significant differences in coronoid, ramus, and condylar heights [10] and these findings are consistent with those reported by Saloni et al. [3], Behl et al. [14], and Vodanovic et al. [15], which found a positive correlation between sexual dimorphism and age and sex estimation in the mandibular ramus.
According to the maximum ramus height and maximum ramus breadth, the ramus showed the highest univariate sexual dimorphism, which is consistent with the findings of Indira et al. [16]. The coronoid height, condylar height, and ramus height were found to be statistically significant between sexes by Chalkoo et al. [17]. Meleveetil et al. [4] concluded that because the mandibular ramus is resistant to damage, it can be used as a useful tool for estimating gender. Three of the five parameters in the Wani et al. [11] study were determined to be significant, with a mean of 79%, gender assessment was accurate at 78% for girls and 80% for males [11]. Dental images based on mandibular ramus and mental indices and their relative positions, according to Kumar and Deepthi [2], are a workable method for forensic analysis of human gender. Males continued to have significantly higher condylar height, coronoid height, and superior border of mental foramen and ramus than females, according to Esfehani et al. [18].
It has been demonstrated that orthopantomography is accurate in measuring anatomical structures. Because there is no superimposition of structures and bilateral measurements can be obtained more accurately, OPGs were favoured over cephalograms. A series of radiographs can be used to assess changes in mandibular size and shape [19]. Magnification and geometric distortion are two drawbacks of digital radiography assessment of the mandibular ramus in forensic dentistry; however, they were addressed in the current investigation. The vertical dimension is slightly different from the horizontal dimension. The mandibular ramus shows substantial sexual dimorphism, as reported by Mostafa et al. [1] and Karmarkar et al. [5], and OPG analysis can be a useful tool for gender determination. As in our study, Astuti et al. [19] also used disproportionate numbers of male and female participants.
Several mandibular morphometric indices, including the bicondylar breadth, intercoronoid distance, and several other vertical and horizontal distances quantifiable on panoramic radiographs, have been proposed for use in forensic gender determination. Gender determination can also be achieved by measuring the vertical and horizontal distances from the mental foramen to the mandibular boundaries [18]. The gonial angle depicts the shape of the mandible. This angle has particular early effects on growth and plays a significant role in growth prediction [8].
When comparing an individual's age and gender with a known population, Shrestha et al. [8] found that mandibular morphometric analysis using radiographic data may help determine these details. Gonial angle is an auxiliary metric that has been applied to orthodontic analysis and forensic identification [8]. The gonial angle of the mandible can be considered a reliable metric for gender identification, according to a study by Sikaria et al. [20]. Female gonial angle values are substantially higher than male gonial angle values, according to research by Leversha et al. [21]. Males showed statistically significantly greater mean gonial angles than females, according to Abuhijleh et al. [22], and gonial angles aid in sex identification.
The current study's findings confirm earlier studies on other groups that found a high level of sexual dimorphism in the mandibular ramus. The limitations of the study included a smaller sample size and difficulty identifying sex when the age range fell below the age at which the mandible had finished growing. Future perspectives should focus on evaluating large sample sizes across broader geographical areas to validate the results.
Conclusion
The mandibular ramus is resistant to injury and disintegration, making it a useful tool for gender assessment.
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Financial Support
None.
Data Availability
The data used to support the findings of this study can be made available upon request to the corresponding author.
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Edited by
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Academic Editor:
Alessandro Leite Cavalcanti
