Clinical, pathological, and genetic evaluations of Chinese patient with otodental syndrome and multiple complex odontoma: Case report

Otodental syndrome is a rare autosomal-dominant disease characterized by globodontia, associated with sensorineural, high-frequency hearing loss. Here, we describe the clinical, pathological, and genetic evaluations of a 9-year-old girl with otodental syndrome and multiple complex odontoma. The patient presented with a draining sinus tract in her left cheek, globodontia, and hearing loss. The odontomas which caused the cutaneous sinus tracts were extracted because of the odontogenic infection. The extracted odontoma and primary tooth was studied by micro-CT and further observed histopathologically. The micro-CT findings revealed that the primary tooth had three crowns with two separated pulp chambers, and their root canals were partially fused. The histological findings showed abnormal morphologies of odontoblasts and dentin, hyperplasia of enamel, and malformation of odontogenic epithelium. Furthermore, DNA sequencing and analyze of deafness associated gene GJB2, GJB3, and PDS had not revealed any SNP or mutation; but exon 3 of the causative gene FGF3 could not be amplified, which may be associated with the microdeletion at chromosome 11q13.3. Three month after surgery, the patient was found to be asymptomatic and even the evidence of the extra-oral sinus had disappeared. The dental abnormality of otodental syndrome included congenital missing teeth, globodontia, and multiple complex odontoma. Globodontia exhibited characteristic features of fusion teeth. In addition, gene FGF3 haploinsufficiency was likely to be the cause of otodental syndrome. The report provides some new information in the field of otodental syndrome, which would make dentists more familiar with this disease.