The influence of cephalometrics on orthodontic treatment planning

Since its introduction, cephalometrics, i.e. cephalometric radiography and analysis, has been used for orthodontic treatment planning. However, the effectiveness of this diagnostic method remains questionable. A randomized crossover study was designed to assess the influence of cephalometrics in orthodontic treatment planning of individual patients. Diagnostic records of 48 subjects (24 males and 24 females aged 11-14 years) were divided in two stratified groups and assigned to one of two combinations: A, dental casts only, and B, dental casts, cephalometric radiographs, and analysis. The records were presented to 10 orthodontic postgraduates and four orthodontists for formulation of orthodontic treatment plans containing a dichotomous decision regarding the use of a functional appliance (FUNC), rapid maxillary expansion (RME), and extraction (EXTR). The combination of FUNC + RME + EXTR was used as the basis of the outcome measure. Agreement on orthodontic treatment planning using all possible comparisons of diagnostic records of individual patients (AB, AA, and BB) was assessed and overall proportions of agreement (OPA) were calculated for orthodontic postgraduates and orthodontists separately. Median OPA were 0.60 (AB), 0.65 (AA), and 0.60 (BB) for orthodontic postgraduates and 0.50 (AB), 0.75 (AA), and 0.50 (BB) for orthodontists. Irrespective of the level of experience, neither consistency of orthodontic treatment planning between both combinations of diagnostic records showed a statistically significant difference (P > 0.05) using Wilcoxon signed rank test nor did consistencies and agreement of orthodontic treatment planning after the addition of cephalometrics. It appears that cephalometrics are not required for orthodontic treatment planning, as they did not influence treatment decisions.