Incomplete mamelon fusion - A rare developmental anomaly

Dental anomalies affect the shape, size, structure and number of the teeth. Any disturbance, during the developmental stage of a tooth encountered, due to a syndrome, exposure to chemicals, drugs, local physical agents, genetic or an isolated anomaly may be detrimental to the tooth. Lobes are the building blocks of tooth crowns. The labial aspect of a permanent maxillary central incisor develops by a union of three lobes, visible as protuberances on the incisal edge, and are termed mamelons. We present a rare developmental anomaly wherein the distal lobe of the central incisor had incompletely fused with the central lobe forming a deep gaping fissure on the coronal aspect, thus predisposing it to dental caries. The case report discusses the identification, etiology, management and differential diagnosis of such a case.