The purpose of this study was to investigate the skeletal changes occu
rring during and after chincap therapy. The subjects of this study, wi
th a mean age of 9 years 3 months, consisted of 27 patients; all of wh
om possessed an anterior crossbite. Of these patients, 15 had skeletal
Class III and the remaining 12 had skeletal Class I malocclusions wit
h anterior crossbites. The applied total force with the chincap was 60
0 grams and the mean treatment period was 12 months. The changes durin
g and after treatment were analysed by using linear and angular cephal
ometric measurements. The result obtained in this investigation was th
at in skeletal Class I and Class III cases, successfully treated by a
chincap appliance, where the necessary overjet and overbite relationsh
ip was obtained, the abnormality tended to return to the original posi
tion during the period following chincap removal.