Since Pierre Robin (1904), Dentofacial Orthopaedics (DFO) implements in its philosophy, harmony or disharmony between form and function in order to manage dental eruption and occlusion. Numerous authors have advocated various orthopedic and fixed appliances,hence creating diverse mainstreams of thoughts. In clinical research, we could not exclude bias due to scholarly or individual considerations. Methods:Two studies using a modified IOTN chart (Index of Orthodontic Treatment Need) were screened for possible bias. The prospective investigation compared the correction of two homogenous samples using orthodontic techniques with or without a functional appliance. Recommendations regarding RCT and procedures were strictly applied. However both screeners were associated with the same dental school using the same technique. Even the final reviewer was a member of the same faculty. In order to avoid such impacts in the second investigation we mixed alphanumeric coded models all together, before, after treatment and recall. Eighty randomized cases were selected for screening their anonymous data. Results: The discovered bias was sufficient to reject any statement in the first study. Following findings of the second one may be considered more valid. There are no differences between males and females or between juniors and seniors in the regression process of the IOTN score and a better recovery in juniors (53,7% or 22 de 41) than in seniors (51.3 % or 20 de 39).Conclusion: Early treatment with orthopedic appliances extends the duration, and reduces the complexity of the appliance