Prosthodontics Overdenture prosthesis for oral rehabilitation of hypohidrotic ectodermal dysplasia: A case report Eslebiin D. Bonilla, DDS*/Luis Guerra. DDS**/Oscar Luna, DDS*** Abstract The dentition ofa patient with ectodertnal dysplasia was restored with a tnodified hollowed maxillary overdenture opposing a conventional mandibular overdenture. Lingualized occlusion was used because it was the ideal occlusal scheme for this patient to achieve denture stability The llngtial cusps oflhe manillar)' posterior teeih contacted thefo.vme ofthe mandibular leeth to create freedotn of movement and to prevent lateral interference. (Quintessence Int ¡997,28.-657-665.) Clinicai reievaiice An overdenture with lingualized occlusion pre- served the existing dentition and created freedom of movement for the patient with complete or partial absence of teeth due to hypohidrotic ectodermal dysplasia. Introduction Ectodermal dysplasia (ED) is a hereditary disorder associated with defective ectodermal structures and their accessory' appendages. '"' There are two forms of ED. the hidrotic and the hypohidrotic. The teeth and the hair are affected similarly in both forms, but the manifestations in nails and sweat glands and the hereditary patterns tend to differ (Table 1). ' Clinical Assistant Professor of Restorative Deniistry, Fixed Prostho- dontics. Sctiool of Dentistry. Universityof California—Los Angeles. Los Angeles. California: School of Dentistry. San Marcos Univer- sity. Lima, Pert!. ** Resident, tnternationai Student Program, School of Dentistry. University of Southern California, Los Angeles. California: School of Dentislry. St Mary 5 Catholic University, Arequipa, Peru. '*" Clinical Assistant Professor. Department of Pédiatrie Dentislry. School of Dentistry, University of San Andres. La Paz. Bolivia. Reprint requests: Dr Esteban D. Boniila. 905 South Lake Street. ? 102. Burbank, California 9150?. E-maiL prosthodiSpop.ben3.UCLA.edu The most frequently reported ED syndrome is x-linked hypohidrotic ectodermal dysplasia (HED). which affects 1 to 7 individuals per 10.000: males are afflicted more frequently ihan females.^"''' The hidrotic form is largely confined to families of French or French-Canadian origin.''"'^ The disorder probably appears during the first trimester of pregnancy. If it is severe, it appears before the sixth week of embryonic life, and. consequently, the dentition will be affected. After the eighth week, the other ectodermal structures may be affected."" The most remarkable characteristics of HED is hypohidrosis. because physical features are not as apparent in the first year of life. It may be diagnosed clinically before the second year of life only after repeated episodes of unexplained fever.-' According to Perabo et al," ectodermal dysplasia may have been recorded as early as 1792 by Danz. in 1838. Wedderburn documented ectodermal dysplasia in a letter to Charles Darwin, describing a case of 10 Hindu male family members. The letter was quoted by Darwin""' in Variations in Plants and Anintals Under Domestication. Thurnam.-'' in 1848, reported two cases of the hypohidrotic form. He found that two cousins and their maternal grandmother had very light and very fine hair, anodontia, and an inability to sweat. Williams described one of his young female patients as having fine, scanty white hair, as well as hypodontia.-'' In 1883. Guilford""^ described a 48-year-old man. edentulous from birth, who had never perspired and had soft, scant, downy hair on his head. Hutchinson."^ 8. Number 10/1997 657