TECHNICAL NOTE ODONTOLOGY Ana A. Barbieri, 1 Ph.D.; Raquel A. Scoralick, 2 M.Sc.; Suely C. M. Naressi, 1 Ph.D.; Mari E. L. Moraes, 1 Ph.D.; Eduardo Daruge, 3 Jr., Ph.D.; and Eduardo Daruge, 3 Ph.D. The Evidence of the Rugoscopy Effectiveness as a Human Identification Method in Patients Submitted to Rapid Palatal Expansion ABSTRACT: The objective of this study was to demonstrate the effectiveness of rugoscopy as a human identification method, even when the patient is submitted to rapid palatal expansion, which in theory would introduce doubt. With this intent, the Rugoscopic Identity was obtained for each subject using the classification formula proposed by Santos based on the intra-oral casts made before and after treatment from patients who were subjected to palatal expansion. The casts were labeled with the patients’ initials and randomly arranged for studying. The palatine rugae kept the same patterns in every case studied. The technical error of the intra-evaluator measurement provided a confidence interval of 95%, making rugoscopy a reliable identification method for patients who were submitted to rapid palatal expansion, because even in the presence of intra-oral changes owing to the use of palatal expanders, the palatine rugae retained the biological and technical requirements for the human identification process. KEYWORDS: forensic science, forensic anthropology, forensic dentistry, victims identification, biometric identification, palatal expansion technique There are innumerable studies in the literature reporting on various different treatments of palatine rugae and investigating whether they undergo significant alterations in their position- ing after treatment (1–3). Most of these studies concluded that the palatine rugae kept the same patterns after the treatments performed, presenting no morphological changes. This, associ- ated with the human identification process, would allow the use of rugoscopy as an alternative method for human identifi- cation. Rugoscopy is the systematic study of the palatine rugae aiming to contribute to the human identification process where other methods are not possible (4). The palatine rugae fulfill the technical and bio- logical requirements needed for human identification because, in addition to their being classifiable (1,2,4), they present individual and immutable characteristics. Another major advantage of this method is that the palate is resistant to the action of fire and macera- tion because of its fibrous structure and anatomically protected position (5,6). Anatomically, the palate consists of the hard palate, covered by orthokeratinized mucosa of remarkable thickness and resil- ience, firmly attached to bone by collagen fibers. The hard palate is the surface that forms the upper wall of the oral cavity and is composed of the palatine processes of the maxillary bone and the horizontal blade of the palatal bone, separated by a system of cruciform sutures (7). The palate mucosa shows a relief or fibrous raphe along the midline because of the embryonic union of the half jaws. In the anterior third of this raphe, there are a varying number of transverse mucosal folds called palatine rugae, which appear asymmetric in humans and are composed of dense fibrous tissue (8). The lamina propria of the palate mucosa joins to the bone by means of anchoring bundles of collagen fibers that are positioned straight, which gives this keratinized tissue a resistance to abrasion and to any tensor forces (strain and deformation) that act in parallel to the palate surface (7,9). Rapid palatal expansion is an orthodontic therapy established for cases of transverse maxillary deficiency (10–12). In order for an occlusion to be considered physiologically normal from the anatomical and functional point of view, it is necessary that the upper premolar and molar palatal cusps occlude the lower premolar and molar pits. For this, the upper arch must be para- bolic and be larger than the lower arch. In cases of transverse maxillary deficiency, the upper arch has a triangular shape. An orthodontic therapy of rapid maxillary expansion can be insti- tuted to correct this deficiency by seeking to increase the trans- versal dimensions of the upper arch by means of an active orthodontic device (13,14). Rapid palatal expansion is not a sim- ple procedure as it acts on the individual’s mid-face, and it is able to correct the transverse dimensions of the maxilla and the 1 Department of Biosciences and Oral Diagnosis, School of Dentistry of São José dos Campos, UNESP – Univ Estadual Paulista; Av. Francisco José Longo, 777 Jardim São Dimas, São José dos Campos, São Paulo CEP – 122450000, Brazil. 2 Department of Dental Biology, Piracicaba Dental School, University of Campinas/UNICAMP – Av. Limeira, 901 Caixa Postal 52, Piracicaba – SP CEP 13414-903, Brazil. 3 Department of Forensic Odontology, Piracicaba Dental School, University of Campinas/UNICAMP – Av. Limeira, 901 Caixa Postal 52, Piracicaba – SP CEP 13414-903, Brazil. Received 28 Sept. 2010; and in revised form 13 Sept. 2011; accepted 29 Oct. 2011. © 2012 American Academy of Forensic Sciences 1 J Forensic Sci, 2012 doi: 10.1111/j.1556-4029.2012.02263.x Available online at: onlinelibrary.wiley.com