The very foundation of the 4 bicuspid extraction concept is based on a very flawed assertion by P. R. Begg’s in 1954, that advocated the low incidence of malocclusion in primitive dentition was due to gritty diets causing interproximal attrition. Begg suggested that this interproximal tooth size width deficit amounted to a pre-molar width in each quadrant. Of course, we now know the lack of malocclusion had more to do with less polution and better upper airway clearance.
http://www.journals.elsevierhealth.com/periodicals/ajorth/article/0002-9416(54)90103-7
Begg’s research has been amply refuted in the literature, no less with his own results; both crowding and attrition increased with age. Pre-molar extraction does not result in more stability. Little’s study in 1981 showed less than 30% of cases 10 years post treatment maintained anterior alignment. (Think about this for a minute. Would any other medical/dental procedure with such success rate endure for this long in any segment of the health profession)?
http://www.ncbi.nlm.nih.gov/pubmed/6945805
But there exists another concept which our orthodontic programs should emphasize and that is the subject of occlusion or rather the causes of mal-occlusion. In his 1963 manifesto, Graber writes “Whenever there is a struggle between muscle and bone, bone yields” .
http://deepblue.lib.umich.edu/handle/2027.42/32220
In their 2005 paper Pepicelli et al, said, “It is well accepted that the position and function of the facial and mandibular muscles are critical influences on alignment and stability”. The literature weighs heavily on the fact that muscle function and posture are the most significant causes of mal-occlusion.
http://www.ncbi.nlm.nih.gov/pubmed/16360920
“Nature is not telling us we need less teeth but rather it is telling us if you mess with me, I mess with you”.
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Brief Background of Dr. Percy Raymond Begg (An orthodontist, researcher, authority and a respected text book orthodontic author and resource to the dental profession).
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