A preliminary study of tongue prints for biometric authentication

Background: Several biometric systems like fingerprints, voice scan, iris scan, and palm scan are currently in use. Biometric authentication is an essential process to identify and verify any person for safety reasons. Tongue print is a new method for biometric identification that is unique and cannot be copied easily. Objectives: This study aims to assess the tongue morphological features and its variations regarding gender and different ethnicities. Methods: The study sample included two hundred fifty participants. Visual examination of the tongue was done, followed by capturing digital photographs. The photographs were analyzed for the surface morphological features like tongue shape, the presence of fissures, and its distribution pattern. The shape of the tongue was determined by considering three reference points. Results: Central fissures are the most common feature seen on the dorsal surface of the tongue. The shallow fissure is more common than deep fissures. Females had a higher number of both deep and shallow fissures when compared to males. U shaped were common in males (52.6%) than females (40.6%), while V-shaped was more in females (56.1%). A significant proportion of Malay race has a U-shaped tongue; meanwhile, V-shaped is predominantly found in Indian race. Conclusions: Tongue prints may constitute secure methods for forensic dentistry identification. The tongue can be a real proof of life as it is unique, and there are no two tongues with similar shape and texture. Lingual morphological aspects are difficult to copy and display stability over time.