Class II Skeletal Growth Modification Treatment: Has Hope Triumphed Over Evidence?

The hierarchy of evidence in the health sciences is primarily determined by study methodology and avoidance of systematic bias. As such, the systematic review and meta-analysis of randomized controlled trials sits at the top of the evidence pyramid while case studies, anecdotes, and personal opinions are located at its base. Ideally, clinical practice guidelines and reference manuals should be developed with this hierarchy in mind and clearly state what level of evidence supports any given clinical recommendation. When there is inadequate evidence to guide a clinical recommendation, we need to clearly state that. Unfortunately, many clinicians do not differentiate between the levels of evidence and consequently elevate highly biased studies to the level of the randomized controlled trial. Nowhere is this more evident than in the American Academy of Pediatric Dentistry Councils on Clinical Affairs’ and Scientific Affairs’ Reference Manual of Pediatric Dentistry best practice statement on the management of the Class II malocclusion.

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