incisorsfour

Incisorsfour is a term used in some dental education materials to denote the four incisors contained in a single dental arch: two central incisors and two lateral incisors. It is not a formal label in standard anatomical nomenclature, but it serves as a concise way to discuss symmetry, eruption, and occlusion within one arch.

In human dentition, each arch—the maxillary (upper) and the mandibular (lower)—houses four incisors: the central incisors (one on each side) and the lateral incisors (one on each side). Incisors are anterior teeth with sharp incisal edges adapted for cutting; they are typically single-rooted.

Morphology varies between central and lateral incisors. Central incisors usually have broader crowns and more pronounced incisal edges, while lateral incisors show greater variation in size and shape. These teeth play a key role in esthetics, speech, and bite function, and their alignment influences occlusion.

Development and eruption: Primary incisors appear in infancy; the four incisors of each primary arch erupt in early childhood. In the permanent dentition, eruption begins around ages 6 to 7 for the central incisors and around 7 to 8 for the lateral incisors, with both arches typically completing their four incisors by early adolescence.

See also: dentition, deciduous teeth, permanent teeth, incisor.