Tags

Type your tag names separated by a space and hit enter

Solitary median maxillary central incisor (SMMCI) syndrome.
Orphanet J Rare Dis 2006; 1:12OJ

Abstract

Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th-38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. 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. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. 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 untreated.

Authors+Show Affiliations

Department of Dentistry, Royal Children's Hospital, Flemington Rd Parkville, 3052 Victoria, Australia. rkingsh@ozemail.com.au

Pub Type(s)

Journal Article
Review

Language

eng

PubMed ID

16722608

Citation

Hall, Roger K.. "Solitary Median Maxillary Central Incisor (SMMCI) Syndrome." Orphanet Journal of Rare Diseases, vol. 1, 2006, p. 12.
Hall RK. Solitary median maxillary central incisor (SMMCI) syndrome. Orphanet J Rare Dis. 2006;1:12.
Hall, R. K. (2006). Solitary median maxillary central incisor (SMMCI) syndrome. Orphanet Journal of Rare Diseases, 1, p. 12.
Hall RK. Solitary Median Maxillary Central Incisor (SMMCI) Syndrome. Orphanet J Rare Dis. 2006 Apr 9;1:12. PubMed PMID: 16722608.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Solitary median maxillary central incisor (SMMCI) syndrome. A1 - Hall,Roger K, Y1 - 2006/04/09/ PY - 2006/03/21/received PY - 2006/04/09/accepted PY - 2006/5/26/pubmed PY - 2006/5/26/medline PY - 2006/5/26/entrez SP - 12 EP - 12 JF - Orphanet journal of rare diseases JO - Orphanet J Rare Dis VL - 1 N2 - Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th-38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. 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. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. 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 untreated. SN - 1750-1172 UR - https://www.unboundmedicine.com/medline/citation/16722608/Solitary_median_maxillary_central_incisor__SMMCI__syndrome_ L2 - https://ojrd.biomedcentral.com/articles/10.1186/1750-1172-1-12 DB - PRIME DP - Unbound Medicine ER -