Cephalometric differential diagnosis of maxillo-mandibular sagittal relations: the ADPI of Kim

Aim. The scope of this experimental study was to verify the validity of the ADPI proposed by Kim,confronting it with the ANB angle and Wits' index.Furthermore,it was intended to consider the correlation between these three parameters and the variations of the vertical scheletral rapports using as indicator Schudy's intermaxillary angle. Methods. We have analised the lateral-side x-rays from 50 subjects between the ages of 7 to 14.After having carried out the cephalometric tracing and,to evaluate the error,we have applied Dalberg's equation.The values from the various APDI measures were studied and elaborated to obtain the average and the standard deviation. Confronting the APDI values with the ANB angle we were able to evaluate the correlation matrix between ANB,Wits and APDI.The following phase was the analysis of the regression between the intermaxillary angle and the respective values of ANB,Wits and APDI. Results. These studies have bought us to recognise a high level of correlation between APDI and the other two parameters. Conclusions. The use of APDI should not substitute the traditional measures because it is reductive and risky,because of this one should resort to the practice of "2 out of 3" using the three forms of cephalometric tracing. Where two parameters are discordant it is always better to consider a third in order to arrive at a more correct diagnosis.