[The causes of incisal overbite].

Why does the eruption of some incisors cease when overbite has reached 3 mm and continue in other cases? Eruption stops only when an opposing force confronts it; normally, this is what occurs when incisors erupt into end-to-end occlusion. Tongue thrusting between molar teeth plays an etiological role only when it interferes with vertical dimension. Incisal overbite diminishes when incisal inclination increases: orthodontists can eliminate incisal overbite by inclining the anterior teeth labially. But a low interincisive angle is no assurance against relapse, because retention, to be reliable, must include a dynamic element, natural or artificial, blocking over-eruption.