Introduction:
The present case report was prepared according to the CARE Guidelines1
Solitary median maxillary central incisor syndrome (SMMCI) is a rare developmental abnormality occurring in utero from the 35th-38th day after the conception2.
The SMMCI is a very complex malformation involving different development defects of the midline structures.These development abnormalities occur in utero from the 35th-38th day after the conception.Defects may involve cranial bones, maxillary bone, airways (mid-nasal stenosis, choanal atresia, nasal pyriform) and midline brain structuresassociated with an increased risk of pituity malformation and malfunction 3,4.
The etiology remains unknown although Nanni et al. suggested that this syndrome may be associated with a missense mutation in the SHH gene (I111F) at 7q36 5.
The presence of an SMMCI tooth can predict associated anomalies and in particular a serious anomaly which is holoprosencephaly5.
Common congenital abnormalities may be also associated with SMMCI such as: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate, less frequently microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophagealor duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia2.
Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18–22 weeks from the routine mid-trimester ultrasound scan.
The SMMCI tooth should be present in all cases and may be detected radiologically prior to its eruption. Eliminating the conditions where only one incisor is present (traumatic loss of one central incisor, fusion of a primary or/and a permanent central incisor with a supernumerary tooth, mesiodens erupting in the midline), there are no other known conditions where this characteristic form of incisor tooth occurs 6.
Management of SMMCI syndrome patients depends upon the individual anomalies present. The SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated6.
The present case report aimed to describe the cranio-facial manifestations of SMMCI syndrome in a 10-years-old girl and discuss the dental treatment alternatives in such young patients.