An evaluation of extraoral combined high-pull traction and cervical traction to the maxilla

The effects of extraoral combined high-pull traction and cervical traction of known duration (mean, 122 days) and magnitude (2.5 to 3 pounds total per side) were studied by means of serial lateral cephalometric head films of thirty patients. The lateral cephalometric head films used were taken at three different times: before the extraoral force was applied, after the prescribed period of continuous headgear wear, and as long as possible after the extraoral force was discontinued. Changes in the dentition and associated structures were described both for the period of continuous headgear wear and for an average of 3.2 years later. The following conclusions are based on statistical analysis of the observed changes: 1. The position of the maxilla and the palatal plane was not significantly affected by relatively short periods of extraoral combined high-pull traction and cervical traction to the maxillary first molars as used for this investigation. 2. The maxillary first molars can be moved distally and bodily with this appliance without extrusion. 3. On the average, the mandibular first molars uprighted distally in response to the extraoral force to the maxilla. 4. The maxillary and mandibular first molars demonstrated a strong tendency to recover to their original positions and inclinations relative to their respective bases during the posttreatment period. 5. The amount and direction of growth in the posttreatment period may be important in determining how the Class I relationship is maintained.