709 Int. J. Morphol., 30(2):709-713, 2012. Palatal Rugae Patterns of Urhobos in Abraka, South-Southern Nigeria Patrones de Rugas Palatinas de los Urhobos en Abraka, Sur-Sur de Nigeria Dennis E. O. Eboh EBOH, D. E. O. Palatal rugae patterns of Urhobos in Abraka, South-Southern Nigeria. Int. J. Morphol., 30(2):709-713, 2012. SUMMARY: Human identification is a major task undertaken in forensic sciences. Palato-rugoscopy is based on the principle that no two palates are the same. The study of palatine rugae and the study of fingerprints are sometimes complementary as they operate in similar methods based on same scientific basis. The study intends to describe the shape and gender distribution of the palatine rugae and their prevalence in the studied population. The study sample consisted of 84 subjects, 42 males and 42 females of Urhobo ethnic and cultural background, between 17 and 30 years old, with full complement of maxillary teeth, drawn purposively from Abraka. The prevalence of palatal rugae shapes was: line (27.2%), sinuous (21.1%), angle (18.1%), polymorphhic (15.5%), point (7.5%), curve (6.2%), circle (4.2%). The total number of palatal rugae shape in the overall sample was 520, with females being slightly higher (51.5%) having mean of 6.38 (SD 1.45) than males (48.5%) having mean of 6 (SD 1.72). However, the difference between male and female was not statistically significant. The individualized pattern of palatal rugae makes it a reliable guiding tool in forensic identification. KEY WORDS: Forensic anthropology; Palatal ruguscopy; Human identification; Morphology. INTRODUCTION Palatine rugae are irregular transverse ridges, radiating outwards from the palatine raphae in the anterior half of the hard palate (Standring, 2008). Patal rugae pattern is an anatomical character of the human palate. Palatoscopy or palatal ruguscopy is the name given to the study of palatal rugae in order to establish a person’s identity (Caldas et al., 2007; Bansode & Kulkarni, 2009). Palatal rugae contain a core of connective tissue (Standring), and are formed in about the 12th week to 14th week of prenatal life and remain stable throughout the person’s life (Bansode & Kulkarni; Patil et al., 2008). The histological study of the development of palatal rugae carried out in mice showed that they develop as localized regions of epithelial proliferation and thickening even in advance of the elevation of the palatal shelves (Luke, 1988; Kapali et al., 1997). Thereafter, fibroblasts and collagen fibers which accumulate in the connective tissue beneath the thickened epithelium assume a unique orientation. The collagen fibres run antero-posteriorly across the base of each ruga and determine the orientation of the rugae (Kapali et al.). Histologically, the palatine rugae have stratified squamous, usually parakeratinized epithelium on connective tissue base (Bansode & Kulkarni). In neonates, the rugae which usually corrugate the hard palate assist gripping of the nipple when suckling (Standring). They are also involved in the oral swallowing and help to improve the relationship between food and the taste receptors in the dorsal surface of the tongue (Buchtová et al., 2003; Hermosilla et al., 2009). The design and structure of palatal rugae are unchanged and are not altered by chemicals, heat, disease or trauma, or, if they are destroyed, are reproduced exactly on the same site they were located (Hermosilla et al.; Almeida et al., 1995). The form, layout and characteristics are not affected by the eruption of the teeth or their loss, but sometimes palatal rugae adjacent to the alveolar arch slightly change their position after tooth extraction (Hermosilla et al.; Peavy & Kendrick, 1967). However, some events may contribute to changes in the pattern of palatine rugae, such as finger sucking in childhood and persistent pressure due to orthodontic treatment. Furthermore, it has been reported that extractions can pro- duce a local effect on the direction of the palatal rugae (Hermosilla et al.; Limson & Julian, 2004). It has been postulated that palatal rugae patterns have genetic undertone (Kapali et al.; Lysell, 1955). Department of Human Anatomy and Cell Biology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Nigeria.