True Generalized Microdontia and Hypodontia with Spondyloepiphyseal Dysplasia

Spondyloepiphyseal dysplasia (SED) is a descriptive term used for group of inherited disorders of bone growth resulting in short stature, skeletal abnormalities, and problems with hearing and vision. SED have three major forms, SED congenital, pseudoachondroplastic SED, and SED tarda. SED tarda is milder than SED congenita. True generalized microdontia is a rare condition in which all the teeth are abnormally small. This is a report of a rare case having SED with generalized microdontia in a 26-year-old patient. 1. Introduction SED refers to a heterogeneous group of disorders with primary involvement of vertebrae and epiphyseal centers of long bones. Three major types of SED are recognized SED congenital, pseudoachondroplastic SED, and SED tarda. Spondyloepiphyseal dysplasia (SED) was first described in 1966 by Spranger and Wiedemann and is now also known as Wiedemann-Spranger syndrome [1]. SED congenita is inherited as an autosomal dominant condition and is associated with a highly disproportional reduction in growth and severe coxa vara, and the milder tarda form which is an X-linked recessive condition, in which growth in adolescence is defective after normal childhood development. Clinically, SED is characterized by short stature (120 to 140？cm), often significant lordosis, pectus carinatum and may have associated features of myopia, retinal detachment, deafness, cleft lip cleft palate, and muscular hypotonia [2]. The genetic modes for SED tarda are various. Initially heredity was described as X-linked, but in later reports both autosomal dominant and autosomal recessive transmission have been demonstrated. In patients of SED tarda, the development up to 5–10 years of age is usually normal after which mild disproportionate trunk and shortening becomes evident. In some patients, the condition remains unrecognized until adolescent years and may become clinically apparent with hip pain, scoliosis or lordosis. SED is rare with its prevalence being approximately 3-4 per million population [3]. The term microdontia (microdentism, microdontism) is defined as the condition of having abnormally small teeth [4]. In generalized microdontia, the teeth are small, the crowns and roots are short, and normal contact areas between the teeth are frequently missing [5]. Shafer, Hine, and Levy divided microdontia into three types: (1) microdontia involving only a single tooth; (2) relative generalized microdontia due to relatively small teeth in large jaws; and (3) true generalized microdontia, in which all the teeth are smaller than normal [6]. According to these