A single maxillary central incisor positioned in the midline with morphological symmetry of the crown and bordered by lateral incisors. The phenotype is Human Phenotype Ontology term HP_0006315 (Solitary median maxillary central incisor). Also known as: Only one upper front tooth, Single central incisor, Single central upper incisor, Single maxillary central incisor, Single median incisor, Single median maxillary incisor, Single midline maxillary incisor, Single midline upper front tooth.