Romanian Journal of Morphology and Embryology 2010, 51(2):371–374 CASE REPORT A simple prosthetic restorative solution of a single peg-shaped upper central primary incisor in a case of ectodermal dysplasia ANCA MARIA RĂDUCANU 1) , MIHAELA PĂUNA 2) , I. V. FERARU 1) 1) Department of Pediatric Dentistry 2) Department of Removable Prosthodontics Faculty of Dental Medicine, “Carol Davila” University of Medicine and Pharmacy, Bucharest Abstract Introduction: This clinical report describes the oral rehabilitation of a 7-year-old male diagnosed with hypohidrotic ectodermal dysplasia and anodontia. Background: Ectodermal dysplasia (ED) comprises a large, heterogeneous group of inherited disorders, which are defined by primary defects in the development of two or more tissues derived from the embryonic ectoderm (skin, hair follicles, nails, teeth, sebaceous and sweat glands). Our patient exhibited the typical general and cranio-facial features of ED as well as emotional and behavioral problems. The patient presents only one conical primary central incisor. Clinical management: The treatment was focused to improve his esthetic needs and oral functions and included the fabrication of removable prostheses and of an acrylic crown on the single tooth existing in his mouth, manufactured by an original simple method. Six months follow-up points out that restorative treatment provided psychosocial and functional comfort to the young boy. Conclusions: This clinical report demonstrates the importance of the prosthodontic treatment for oral rehabilitation in children with ED. The partial and complete removable dentures associated with the acrylic crown can be a reversible and inexpensive method of treatment for ED patients. Keywords: hypohidrotic ectodermal dysplasia, ED, anodontia, prosthodontic treatment, acrylic crown.  Introduction Ectodermal dysplasia (ED) comprises a large, heterogeneous group of inherited disorders (there may be over 150 different types) [1–3], that are defined by primary defects in the development of two or more tissues derived from embryonic ectoderm [1, 2, 4–7]. ED is present worldwide affecting all races, most often in whites [2]. The most common EDs are X-linked recessive hypohidrotic/anhidrotic ED [2, 5, 7, 8]. It has full expression only in males. Female carriers show little or no signs of the condition [2]. Most of the EDs manifest variable defects in the morphogenesis of ectodermal structures such as the hair, skin, nails, teeth and sweat glands witch produce numerous general findings and symptoms, thus the clinical features associated with ED may vary from case to case [7–10]. Characteristic deformities of the skull are: square aspect of the forehead, frontal bossing, prominent supra- orbital ridges, saddle nose, the alae nasi appears hypoplastic, the midface is depressed and hypoplastic, the cheekbones are high and broad (malar hypoplasia) and appear flat and depressed as well (dished-in appearance), the chin may be pointed and the lips are thick and everted, cleft lip or palate [3, 11]. The patient may resemble an edentulous old person [3]. The cranio- facial deviations increase with advancing age, in non- treated patients, with a tendency towards a Class III pattern, decreased lower facial height, the maxilla is more retruded as the mandible, the mouth width is smaller than normal [11]. The dental anomalies are: number anomalies (ano- dontia or severe hypodontia) [1, 5, 6, 8], shape anoma- lies (peg-shaped conical incisors and canines both in deciduous and permanent dentitions, talon cusp, tauro- dontia) [1, 4, 5, 8], size anomalies (microdontia in both affected males and carrier females) [5], structural ano- malies (hypoplasia). Partial or total anodontia results in some loss of function, such as chewing and esthetics [12]. Other oral manifestations are: small or atrophic gums, inflammatory and/or infectious stomatitis, dys- phonia, dysphagia, feeding difficulties, hearing impair- ment [8], xerostomia causes problems with chewing, swallowing food, lack of sense of taste or smell [6, 9, 12].  Patient, Material and Methods The oral rehabilitation of a 7-year-old male with X-linked recessive anhidrotic ectodermal dysplasia is presented. The Romanian mother displays some milder clinical manifestations of ED such as: absence of the maxillary lateral incisors, some facial distortions (Figure 1). The Chinese father and his family are completely healthy.