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M. R. Ambedkar Dental College and Hospital, India
Corresponding Author: Poojya R, M. R. Ambedkar Dental College and Hospital, India. E-mail: poojyaprashanth@gmail.com.
Running title: TONGUE PRINTS IN FORENSIC DENTISTRY
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ABSTRACT |
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INTRODUCTION |
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TONGUE EXAMINATION |
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CLASSIFICATION |
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TONGUE PRINT COLLECTION |
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DISCUSSION |
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CONCLUSION |
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REFERENCES |
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ABSTRACT
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Tongue print or lingual impression is a new biometric authentication method used in forensics. Every tongue has its own lingual impression, because of its unique shape and texture. Tongue print is the information carried on the exposed portion of the tongue, that is shape and texture all together. Many studies have been researched into preparing a proper algorithm for tongue image analysis.
Digital photographs, lingual moulded impressions, rugoscopy, cheiloscopy, sublingual vein analysis, ultrasound, histological analysis are some of the methods of tongue print collection. Forensic dentistry deals with the proper handling, examination, and evaluation of dental evidence which will be presented in the interest of justice.
With the increase in identity fraud and emphasis on security, there is an urgent need to identify humans locally and remotely on a routine basis. Hence newer advancements and research on the potential of tongue prints, as an authenticated forensic tool has to be done.
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INTRODUCTION |
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Tongue is a pivotal muscular organ well encased within the oral cavity, and well protected from the external environment. Tongue print or lingual impression is a new biometric authentication method used in forensics. Every tongue has its own lingual impression because of its unique shape and texture. Tongue is a unique organ which can be stuck out of the mouth for inspection and palpation and acts as a proof of life, well protected in the mouth and difficult to forge. Tongue print is the information carried on the exposed portion of the tongue, that is shape and texture all together. Many studies have been researched into preparing a proper algorithm for tongue image analysis (1).
Tongue is an organ of the body which performs many actions like articulation of speech, perception of taste and formation of food bolus. Tongue is enclosed in the oral cavity, with palate on the superior aspect, floor of the mouth on the inferior aspect, mandibular teeth on the lateral aspects, posteriorly bounded by pharyngeal aspect and anteriorly by lips. Tongue is a vital organ and its vitality is described in traditional Chinese medicine as “TONGUE OF LIFE” where in tongue has a vital color. In contrast the “TONGUE OF DEATH” in traditional Chinese medicine TCM is termed due to its dark and withered appearance. Tongue also gives information regarding health status of an individual. The tongue provides both static and dynamic features for authentication.
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TONGUE EXAMINATION |
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Examination of the tongue was carried out after prior cleaning with sterile gauze piece, together with rinsing of the oral cavity. Tongue is protracted in a relaxed position to prevent marked contraction of striated lingual muscles. Tongue examination is done in frontal and profile view. Examination of tongue shape, texture, lateral grooves, lingual apex, and any physiological fissures can be viewed.
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CLASSIFICATION |
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The shape of the tongue is analyzed by reference points on the lingual tip and v shaped lingual sulcus. Based on these features stefanescu et al 2014 classified tongue features as (Table 1 and Table 2):
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TONGUE PRINT COLLECTION |
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Many studies have been formulated related to the development of tongue image database, which recorded the geometrical shape of the tongue and its surface texture. Scanning of the tongue image can be done using intraoral scanners and converted to digital format of software with the help of biometric input by identification of specific points. Many studies have been researched into preparing a proper algorithm for tongue image analysis. Digital photographs, lingual moulded impressions, rugoscopy, cheiloscopy, sublingual vein analysis, ultrasound, histological analysis are some of the methods of tongue print collection. Rugoscopy is the study of palatal rugae, and their uniqueness to individuals, can provide a reliable source of identification. Cheiloscopy is a forensic investigation technique, that deals with identification of humans based on lip traces. Forensic dentistry deals with the proper handling, examination, and evaluation of dental evidence which will be presented in the interest of justice (2).
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DISCUSSION |
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The uniqueness of the tongue by the analysis of shape and texture, reveals visible differences between one individual and another, making it a useful tool in personal identification. Dorsal surface of the tongue provides valuable details for personal identification due to genetic independence, as no two tongue are the same in its shape and surface texture. Other advantages being stability overtime, physical protection in the mouth, therefore difficult to forge.
Various indications of tongue print analysis include security purpose for individual identity, tongue is unique with respect to shape and surface texture, in cases of calamities of fire incidence, it is well protected from external environment. Tongue print analysis is contraindicated in cases of acquired pathologies in the tongue.
Lingual moulding technique of impression making together with photographic image, rugoscopy and cheiloscopy are some of the best methods for analyzing tongue as a biometrics. Sublingual vein analysis also helps in tongue diagnosis (3). Ultrasound transducers placed in sublingual area is also used to assess the function of the tongue. Histological examination can also be done.
Digital software has been formulated which autocorrects for the color and hue along with the positional alterations and camera conditions and then analyses the tongue for its color and texture to match with its database to bring about positive identification (4).
Studies have shown specific differences in the tongue characteristics between men and women showing sexual dimorphism. According to stefansu et al geographic tongue is seen in females than in males. Plaqued tongue is more common in elder male people (5). Characteristics of tongue tip being 70%rounded, 21.7% pointed, 8.3% septate tip.
Numerous advantages exist in using tongue print over other biometric systems such as fingerprint, voice check, and retinal scan. The tongue is unique to every person with respect to its shape and surface textures. Since it is an internal organ, it can be easily exposed for inspection and the exposed surface carries the required information. The physiological texture and shape remain constant. It is well protected from the external environment, and so it is not affected by external factors. It is also a reliable proof of life. In recent years, tongue print is gaining momentum as an important tool in biometric authentication (6).
The advantages of the gumming technique are that it is economical and pocket friendly. The technique has a conservative approach and the wastage of the material can be avoided (7).
Other methods tried were videography of tongue and extracting images from the same for it being a non-rigid organ. Other alternate methods that include sublingual vein analysis, are too one of the methods that help in tongue diagnosis (8).
Tongue Prints, as a new biometric authentication method has been found beneficial for identification although in India this identification system is still at grass-root level and needs more amount of research and planning to implement and dentist can play an important role to make Tongue Prints as a widely available and acceptable tool (9).
Sexual dimorphism in tongue characteristics plays an important role in personal identification. It has been identified that, there are specific differences or variations in the tongue characteristics between men and women. It has been observed that scrotal tongue and geographic tongue were characteristic of female patients. According to a study, patients with sharp tip at the lingual apex were females and patients with septate tips were males. When comparing the length and width of the tongue between men and women, it has been observed that male patients were having an increased length and width when compared to female patients. When histologically examined there was a significant difference in the orientation of the muscle fibers of the tongue among men and women. These differences were seen in the middle region of the tongue (10).
The use of tongue prints as biometric authentication tool is under research, and studies have found it to be an effective means of identification as compared to other biometric tools. What remains constant is the physiological shape and texture of the tongue. One of the few factors that can hinder the tongue print analysis includes, pathologies and anomalies of the tongue ,which are acquired and which can hamper the identification process.
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CONCLUSION |
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The tongue is a unique organ exhibiting many static and dynamic characteristics, which differs between individuals. With the increase in identity fraud and emphasis on security, there is an urgent need to identify humans locally and remotely on a routine basis. Hence newer advancements and research on the potential of tongue prints, as an authenticated forensic tool has to be done.
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REFERENCES |
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