Objective: To compare changes in maxillary position assessed from a maxillary implant and three cephalometric methods based on linear measurements.
Methods: Series of tracings of the maxilla obtained around puberty from an implant study were analyzed. The displacement of the implant was used to determine the direction and amount of "actual" maxillary growth. Displacement of point A was measured according to three cephalometric methods. The values obtained from absolute, horizontal, and vertical displacement of point A by three cephalometric methods and by the implant method were compared.
Results: Results showed that estimation of displacement of the maxilla by three cephalometric methods (point A) was significantly larger than that of the implant method in all directions. The average difference in the horizontal plane was 0.7 mm, 1.2 mm, and 1.6 mm, respectively; the average difference in the vertical plane was 2.2 mm, 2.5 mm, and 3.6 mm, respectively.
Conclusions: Estimations of changes in maxillary position by the implant method and by cephalometric methods were not proportional. All three cephalometric methods overestimated changes in the position of the maxilla.