Overjet

Overjet is the horizontal measurement of how far the incisal edges of the maxillary anterior teeth project forward beyond the incisal edges of the mandibular anterior teeth, evaluated in the sagittal plane with the teeth in centric occlusion. Normal overjet is typically 2 to 3 millimeters. When overjet exceeds this range, the upper front teeth visibly protrude, a presentation commonly described in lay terms as buck teeth. Excessive overjet can result from a protrusive maxilla, a retrognathic mandible, proclined upper incisors, retroclined lower incisors, or a combination of skeletal and dental factors. Overjet is distinct from overbite, which measures the vertical overlap of the anterior teeth rather than the horizontal projection.

Patients with excessive overjet face an elevated risk of traumatic injury to the protruding upper incisors, particularly during sports, falls, and other physical activities. Studies have demonstrated that overjet exceeding 6 millimeters roughly doubles the incidence of dental trauma compared to normal overjet values. Beyond trauma risk, excessive overjet can impair lip competence, making it difficult for the patient to close the lips comfortably at rest, which contributes to mouth breathing, dry mouth, and anterior tooth decay. Orthodontic correction typically involves retracting the upper incisors, advancing the lower arch, or a combination of both, often in conjunction with functional appliances in growing patients to modify skeletal jaw relationships. Treatment duration depends on the severity of the overjet and whether the underlying cause is primarily dental or skeletal.

Overjet is one of the most commonly documented metrics in orthodontic preauthorization submissions. Most insurance carriers that provide orthodontic benefits require a specific millimeter measurement of overjet as part of the diagnostic record, and many plans set a threshold (often 5 to 6 millimeters) above which treatment is considered medically necessary. The billing team should ensure that the preauthorization package includes the measured overjet value, clinical photographs showing the anterior relationship, and a cephalometric radiograph that differentiates between skeletal and dental contributors to the overjet. When the overjet has resulted in documented dental trauma, including this history in the submission strengthens the medical necessity argument. Orthodontic treatment is billed under the D8000 code series, and practices that submit complete, well-documented preauthorization packages experience faster approvals and fewer requests for additional information.