Evaluation of orthodontic results--a discussion of some methodological aspects.

The informative value of clinical material presented at meetings and in the literature poses a dilemma for the typical orthodontist. To aid in the resolution of this problem, methodological aspects of the following topics are discussed: criteria for the evaluation of orthodontic treatment results, the selection of cases to be evaluated, the presentation of orthodontic treatment results and the interpretation of case presentations. Orthodontic relapse should be considered to be a number of continuous variables affecting treatment results; different follow-up criteria should be employed when comparing pretreatment, posttreatment and postretention results.