Key Clinical Message
We reported dental and craniofacial characteristics of a patient with SJS and severe OSA. These findings demonstrate that children with SJS could be affected not only on general physical features but also craniofacial development.
Introduction
Schwartz-Jampel Syndrome (SJS1, ORPHA:800; OMIM#255800) is a very rare genetic disorder with prevalence less than 1:1,000,0001. SJS, named after Schwartz and Jampel (1962)2, is an autosomal recessive disorder caused by mutations in HSPG2 gene. This gene encodes for perlecan, a cellular matrix protein regulating muscle contraction and chondrogenesis.3 A defective HSPG2 gene results in prominent SJS features of prolonged muscle contraction (myotonia) and multiple skeletal abnormalities (chondrodysplasia). Facial dysmorphology is distinctive and rather consistent across ethnicities.4 There are approximately 130 SJS reports in the current literature with only a few describing dental findings. Díaz-Serrano et al .5 delineated oral manifestations such as dental crowding, high-arched palate, multiple impacted teeth and TMJ problem found in two siblings with SJS. Mallineniet al .6 reported a Chinese boy with SJS who presented with bulbous crowns with marked cervical constriction, amber-brown discoloration, brittle enamel, soft dentine, and severe attrition in his primary teeth. A macrodontic primary incisor and a congenitally missing permanent incisor were also described in the same patient.6 In this paper, we present an 8-year-old male patient with SJS and severe obstructive sleep apnea (OSA). To the best our knowledge, this is second SJS case with OSA reported in the literature after Cook and Borkowski.7 In addition to oral findings, a craniofacial morphology of this patient will be presented.