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.