A study of the anterior portion of the palate as it relates to orthodontic therapy.

1. The anterior portion of the palate does not appear to move lingually as orthodontic forces move incisor teeth lingually. Although the alveolar bone directly supporting the teeth can be moved distally (and elongated), it does not appear possible to move the apex of the root more distally than the pretreatment position of the palatal plate. Thus, there appears to be an anatomic limitation to the distal movement of maxillary incisor teeth. 2. When incisor teeth are moved distally within the boundaries of the present alveolar process, the supporting bone does not remodel to the roots' new position; when a root which was initially positioned nearer the labial alveolar plate is moved distally against the palatal plate, there was observed no adaptation in the bone to have the root once again located near the labial alveolar plate, the root remained stable against the palatal plate. 3. When great distal movement of incisor teeth results in an alteration in position of the supporting alveolar bone, remodeling of the bone maintains a relatively constant labiolingual width of this alveolar bone. The new position of the tooth and supporting bone appears to be stable. 4. The scanty metallic implant evidence would seem to support histologic observations that alveolar processes are remodeled by apposition of bone on the cortical plate toward which the tooth is moving and resorption of the cortical plate away from which the tooth is moving. 5. There does not appear to be a statistically significant correlation between posterior facial measurements (SNMP) and the labiolingual width of the anterior palate.