Case Presentation
A 4-month-old boy, who previously presented for a sizable gingival hemangioma on the lower gingiva two months earlier and was being treated with propranolol and monthly follow-up, now presented with a sudden onset of a white lesion in the upper gingiva that caused great discomfort during breastfeeding to his mother one morning. Examination of the oral cavity revealed in the midline of the upper gingiva, a primary dental eruption reminiscent of a tusk or a fang due to its incurved crown and sharp vertex ( Figure 1A ).

While waiting dental and maxillofacial surgery consultations, the lesion abruptly disappeared. A small central mucosal swelling with a slightly hemorrhagic pedicle at the site of detachment remained visible.
Teaching Point
Strictly speaking, this is not a neonatal tooth nor is it a natal tooth. That said, its early decay suggests a somewhat premature dentition with different structural characteristics than the transitional teeth that persist until the time of definitive dentition.
Solitary median maxillary central incisor syndrome is a mild manifestation of the holoprosencephaly spectrum, typically exhibiting an eruption of normal morphology in the midline of the maxillary alveolus at age of 8 months; present in both primary and permanent dentition [ 1 , 2 ] . An initial head ultrasonography was performed with no anomaly being found.
Considering the absence of other malformative elements, genetic evaluation was postponed to a later period of life. At age of 6 months, the boy developed an eruption of the upper left canine and lower central incisor teeth of normal morphology ( Figure 1B ).
References
- Solitary median maxillary central incisor (SMMCI) syndrome Hall RK. Orphanet J Rare Dis.2006;1:12. CrossRef PubMed
- The solitary median maxillary central incisor (SMMCI) syndrome: Associations, prenatal diagnosis, and outcomes Garcia Rodriguez R, Garcia Cruz L, Novoa Medina Y, et al. Prenat Diagn.2019;39(6):415-419. CrossRef PubMed
Figure 1 .
(A) Tusk-shaped primary dental eruption in the midline of the upper gingiva at age 4 months. (B) Primary eruption of the upper left canine and lower central incisor teeth at age of 6 months.