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Table of Contents
ORIGINAL ARTICLE
Year : 2018  |  Volume : 6  |  Issue : 3  |  Page : 17-20

Assessment of different palatal rugae patterns in gender identification


1 Department of Oral Medicine and Radiology and PSM College of Dental Science and Research, Akkikavu, Thrissur, Kerala, India
2 Department of Oral and Maxillofacial Surgery, PSM College of Dental Science and Research, Akkikavu, Thrissur, Kerala, India
3 Department of Oral Medicine and Radiology, St. Gregorios Dental College, Kothamangalam, Ernakulam, Kerala, India

Date of Web Publication17-Jan-2019

Correspondence Address:
Dr. Beenakumary Thiruthara Pappu
Department of Oral Medicine and Radiology, PSM College of Dental Science and Research, Akkikavu, Thrissur, Kerala
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/INJO.INJO_11_18

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  Abstract 

Background: The palatal rugae number, shape, width, height, and location vary from the left side of the palate to the right side as well as from one person to another, and are unique to every individual. This is the most commonly used scientific method of forensic identification. So this study was conducted with an aim to assess the different patterns of rugae in gender identification. Materials and Methods: This study comprised 40 participants (20 men and 20 women) between the age of 20 and 35 years. Maxillary impression was carried out and cast was poured. The rugae were divided into two halves and each half was highlighted using a lead pencil under spotlight by the examiner. Rugae pattern was classified into straight, wavy, circular, curved, and unification. The shape, number, and length of rugae pattern were studied over cast by the examiner and the mean value for length and numbers was then calculated. The length of each rugae was measured using a vernier caliper in millimeters (mm). Results: The mean number of palatal rugae was more in men (6.16±0.226) compared to that in women (5.86±0.364). The mean length of palatal rugae was more in men (5.96±0.64) than that in women (4.28±0.34), and it was found to be statistically significant (P = 0.02). In this study, the straight pattern was more common in both men and women (2.32±0.12 and 1.98±0.02, respectively) than other patterns. But none of the pattern shows a statistically significant association between the different patterns with gender. Conclusion: Straight rugae pattern is the most common pattern in both the groups and the mean number of palatal rugae and length is slightly more in men than that in women.

Keywords: Dental cast, forensic dentistry, gender, palatal rugae, rugae pattern


How to cite this article:
Pappu BT, Gopinathan TA, Naduvakattu B. Assessment of different palatal rugae patterns in gender identification. Int J Oral Care Res 2018;6:17-20

How to cite this URL:
Pappu BT, Gopinathan TA, Naduvakattu B. Assessment of different palatal rugae patterns in gender identification. Int J Oral Care Res [serial online] 2018 [cited 2019 Apr 19];6:17-20. Available from: http://www.ijocr.org/text.asp?2018/6/3/17/250270




  Introduction Top


Forensic odontology is a specialty in dentistry, which occupies a primary place within the total spectrum of methods applied to medicolegal identification. Deoxyribonucleic acid (DNA), fingerprint, and dental record comparisons are the most commonly used scientific methods of forensic identification. Constraints to the use of fingerprints occur in situations where the hands are charred or mutilated. Though teeth are more durable, it is, however, not practical to use them in identifying the edentulous persons. A useful method of human identification in these circumstances is by examining the palatal rugae pattern.[1]

Palatal rugae appear in the 3rd month of intrauterine life. Because of its anatomic position, rugae are protected from thermal insults by the tongue and buccal pad of fat. Rugoscopy involves the study of palatal rugae pattern for human identification. Due to the stability and uniqueness of the palatal rugae pattern, it has been considered as one of the relevant parameters for human identification in the field of forensic medicine. Palatal rugoscopy was first proposed by Trobo Hermosa in 1932. The analysis of palatal rugae was first proposed by Allen in 1889. Rugoscopy is useful in mass disasters where conventional methods are not feasible.[2]

Palatal rugae are transverse ridges of the mucosa located at the upper jaw, on the anterior portion of the hard palate. The number, shape, width, height, and location of palatal rugae vary from the left side of the palate to the right side as well as from one person to another, and are unique to every individual. Recent studies have suggested that palatal rugae could be used in forensic identification.[3],[4] Palatal rugae remain stable throughout life, and therefore, they are commonly used by dental clinicians as a reference point to evaluate the extent of tooth movement.[5]

Palatal rugoscopy may be used as a necro-identification technique. It can be of special interest in those cases where no fingerprints are available such as decomposed bodies, burned bodies, and conditions where both the upper limbs are missing. It is the most valuable technique in aeronautical accidents to ensure identification of pilots making use of antemortem data.[6] Hence, this study was conducted to assess the different patterns of rugae in gender identification.


  Materials and Methods Top


This study comprised 40 participants (20 men and 20 women) between the age of 20 and 35 years, selected from the outpatient department of oral medicine and radiology. All participants were healthy individuals free of congenital anomalies, inflammation, trauma, or orthodontic treatment. The purpose of this study was explained to the participants and consent was obtained from them.

Impression of maxillary arch

Maxillary impression trays were selected according to the shape and size of the patient’s arches. Two levels of alginate impression material were taken in the scoop and mixed with 40mL water (using a measuring jar provided by the manufacturer), in a water/powder (W/P) ratio of 40:15 (mL:g), in a flexible rubber bowl with a mixing spatula. A vigorous figure-eight motion was used for mixing. The mix was immediately transferred to the impression tray for insertion into the patient’s mouth. The tray was held passively and motionless during the setting of impression material. After approximately 2min (setting time of alginate), the tray was separated quickly from the teeth to avoid rocking and possible deformation of the fine areas of the impression. Excess material at the periphery was trimmed. The casts were poured subsequently.

Method of palatal rugae identification

A midline was drawn coinciding with that of the mid-palatine raphe extending from the incisive papillae to the posterior most extent of the rugae on the palate. This divided the rugae in two halves and the rugae in each half were highlighted using a lead pencil under spotlight by the examiner. The pattern of rugae was determined using Thomas and Kotze[7] classification. It classifies the rugae pattern into straight, wavy, circular, curved, and unification. The shape, number, and length of rugae pattern were studied over cast by the examiner and the mean value for length and numbers was then calculated. The length of each rugae was measured using a vernier caliper in millimeters (mm).

Statistical analysis

The collected data were sorted, tabulated, and subjected to statistical analysis. The data obtained were transferred to Microsoft Excel and then to the Statistical Package for the Social Sciences (SPSS) software (version 20, IBM SPSS Inc, Chicago) for analysis. Independent sample t-test was used to assess the significant difference of the total number of each type of palatal rugae between men and women. Descriptive statistical analysis was applied using SPSS to obtain the mean values and standard deviation from the data of each category.


  Results Top


[Table 1] shows the association of mean number of palatal rugae and gender. The mean number of palatal rugae was more in men (6.16±0.226) compared to that in women (5.86±0.364), and a statistically significant association was found between them. [Table 2] reveals that the mean length of palatal rugae was more in men (5.96±0.64) than that in women (4.28±0.34). It was found to be statistically significant (P = 0.02). [Table 3] shows that the straight pattern was more common in both men and women (2.32±0.12 and 1.98±0.02, respectively) than other patterns. But none of the pattern shows a statistically significant association between the different patterns with gender.
Table 1: Association of mean number of palatal rugae and gender

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Table 2: Association of mean length of palatal rugae and gender

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Table 3: Association of mean of palatal rugae pattern and gender

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  Discussion Top


Since we entered the new millennium, our society is daily facing multiple challenges in every conceivable area. The most important role of a forensic dentist is the identification of diseased individuals with oro-dental remains in tragedies, disasters, and massacres. Human identification is the mainstay of civilization, whether in living or dead conditions, and the identification of unknown individual has always been of paramount importance to our society. Human identification is based on scientific principles, mainly involving dental records, fingerprints, and DNA typing. Sometimes, it becomes necessary to apply a lesser known and unusual technique such as rugoscopy.[4],[8]

In this study, straight pattern was found to be more common in both men and women, which was similar to the study conducted by Balgi et al.[2] These results were in contrast to the study conducted by Kumar et al.,[9] and Surekha et al.[10] showed the predominance of curved and wavy pattern of rugae in most population.

In this study, we measure the length, number, and pattern of the palatal rugae over the cast. Jacob and Shalla[11] reported 100% accuracy from the tracings of entire cast and 79% accuracy with palatine rugae. Limson and Julian[12] evaluated the photographs of delineated rugae patterns of the cast using a computer software program and the reported digitized rugae patterns matched the patterns in the stored records with highest sensitivity and specificity.

The three main methods used in the field of forensic identification are the visual, fingerprints, and dental characteristics. In numerous instances, these methods may not be totally effective or conclusive. Many investigations dealing with aircrafts and bomb explosions lead to loss of evidence, and human dentition becomes the prime method of determining the individuality. The use of palatal rugae serves as an important aid in forensic identification as they are placed in a much internal position and are insulated from heat by the tongue and buccal mucosa. The uniqueness and individuality of the palatal configuration further support rugoscopy as a useful tool in forensic science. The rugae remain stable thought the life of an individual in terms of number and morphology except in the case of orthodontic tooth movement, trauma, extreme finger sucking, and persistent pressure, which may modify the alignment.[13],[14] The application of palatal rugae in gender determination could be attributed to low-utilization cost, simplicity, and reliability.[15] This study clearly shows that palatal rugae are unique to each individual, and rugae pattern with its different parameters can be used successfully as a tool of identification.


  Conclusion Top


Straight rugae pattern is the most common pattern in both the groups, and the mean number of palatal rugae and length is slightly more in men than that in women. As this study had a limited sample size of 40 subjects, it will be beneficial to conduct studies with larger sample and to compare with ethnic groups.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Selvamani M, Hosallimath S, Madhushankari, Basandi PS, Yamunadevi A. Dimensional and morphological analysis of various rugae patterns in Kerala (South India) sample population: A cross-sectional study. J Nat Sci Biol Med 2015;6:306-9.  Back to cited text no. 1
    
2.
Balgi P, Bhalekar B, Bhalerao K, Bhide E, Palaskar S, Kathuriya P. Study of palatal rugae pattern in gender identification. J Dent Allied Sci 2014;3:13-6.  Back to cited text no. 2
  [Full text]  
3.
Taneva ED, Johnson A, Viana G, Evans CA. 3D evaluation of palatal rugae for human identification using digital study models. J Forensic Dent Sci 2015;7:244-52.  Back to cited text no. 3
[PUBMED]  [Full text]  
4.
Kapali S, Townsend G, Richards L, Parish T. Palatal rugae patterns in Australian aborigines and Caucasians. Aust Dent J 1997;42:129-33.  Back to cited text no. 4
    
5.
Ekrem Oral S. Kutalmıs B, Huseyin S. Evaluation of palatal rugae pattern in different sagittal skeletal relationship adolescent subjects. Medicine 2017;96:14.  Back to cited text no. 5
    
6.
Mahabalesh S, Premalatha K. Study of palatal rugae pattern among the student population in Mangalore. J Indian Acad Forensic Med 2011;33:112-5.  Back to cited text no. 6
    
7.
Thomas CJ, Kotze TJ. The palatal ruga pattern in six southern African human populations, part I: A description of the populations and a method for its investigation. J Dent Assoc S Afr 1983;38: 547-53.  Back to cited text no. 7
    
8.
Subramanian PR, Jagannathan NI. Palatal rugoscopy as a method of sex determination in forensic science. Asian J Pharm Clin Res 2015;8:136-8.  Back to cited text no. 8
    
9.
Kumar S, Vezhavendhan N, Shanthi V, Balaji N, Sumathi MK, Vendhan P. Palatal rugoscopy among Puducherry population. J Contemp Dent Pract 2012;13:401-4.  Back to cited text no. 9
    
10.
Surekha R, Anila K, Reddy VS, Hunasgi S, Ravikumar S, Ramesh N. Assessment of palatal rugae patterns in Manipuri and Kerala population. J Forensic Dent Sci 2012;4:93-6.  Back to cited text no. 10
[PUBMED]  [Full text]  
11.
Jacob RF, Shalla CL. Postmortem identification of the edentulous deceased: Denture tissue surface anatomy. J Forensic Sci 1987;32:698-702.  Back to cited text no. 11
    
12.
Limson KS, Julian R. Computerized recording of the palatal rugae pattern and an evaluation of its application in forensic identification. J Forensic Odontostomatol 2004;22:1-4.  Back to cited text no. 12
    
13.
Babaji P, Jalal SA, Kamalaksharappa SK. Evaluation of palatal rugae pattern in identification and sex determination in Indian children. Pesq Bras Odontoped Clin Integr 2018;18:e3944.  Back to cited text no. 13
    
14.
Sekhon HK, Sircar K, Singh S, Jawa D, Sharma P. Determination of the biometric characteristics of palatine rugae patterns in Uttar Pradesh population: A cross-sectional study. Indian J Dent Res 2014;25:331-5.  Back to cited text no. 14
[PUBMED]  [Full text]  
15.
Chopra A, Rao NC, Gupta N, Vashisth S. Palatal rugae and arch length: A tool in gender determination. Univ Res J Dent 2013;3:54-9.  Back to cited text no. 15
  [Full text]  



 
 
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  [Table 1], [Table 2], [Table 3]



 

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