July 02, 2018
A brilliant “take down” of myofunctional/orthotropics philosophy
I came across this brilliant and withering criticism of a recent book that promotes the magical thinking behind myofictional orthodontics, orthotropics and the epidemic of malocclusion.
This was published in another orthodontic blog that is written by Professors from the University of North Carolina. The blog is good and worth following. This post was excellent. The comments on John Mew and orthotropics are particularly interesting.
I have been away on holiday and I have not had time to write a post of my own, so I thought that I would just point you to this great blog post.
Just follow the link
Jaws: Dr Proffit and Dr Ackerman review a sensationalist book.
I hope that you read this and I will be back to normal posting next week.
Please correct me if I am wrong but my understanding is that the scientific proof of conventional treatment outcome is that it is unstable and requires life long retention. Perhaps then it is time to look for something better. This book provides some excellent arguments.
For those interested in evolutionary biology, I would strongly recommend Richard Prum’s Puliver Prize winning book entitled “The Evolution of Beauty”. Great read!!!
Have to agree with the analysis by the two professors. This field of myotherapy/orthotropics seems like quackery with little to no basis in science. Who says conventional treatment is unstable and who says the “solution” is stable? The book was obviously written to sell a totally discredited philosophy. Thank you for posting the link…even in France, this madness seems to be on the rise.
Then why is life long retention required?
In the introduction, the Reviewers do not provide their definition of ‘malocclusion’ making the assumption that there is an universally-agreed definition, of which I am not aware [1]
Paragraph 1 of the critique starts with an error. It should read “Labeling malocclusion as a disease of civilization” not ‘orthodontics’?
The citation of Corruccini’s research of rural and urban Punjabis is misquoted and misleading in my understanding of their paper. Where is the Reference for this?
Jaw size
Para 1: Phenotypic variation can occur rapidly (perhaps in one generation). Please note Dr Crick’s idea (who worked with Dr Watson on DNA structure) of the Big bang theory of human brain evolution. He claimed that the human brain evolved very fast in evolutionary history (like a hurricane building a Chevvy by passing thru a junk yard, or words to that effect).
Para 2: Yes there is evidence of genetic influence on both jaw size and jaw relationships. However, the ‘jaws’ are not homogeneous. The maxilla is devoid of cartilage unlike the mandible, and genetic mutations of cartilage can produce phenotypic variation, for example, the Hapsburg jaw. Moreover, genetic mutations of the cartilage of the cranial base can have epigenetic effects on the face and therefore the jaws and teeth [2]. These epigenetic phenomena might explain clinical facies, such as those seen in Down syndrome, for example.
Orthodontic treatment
The Reviewers obfuscate the reader by incorrectly ascribing the myofunctional concept to Mew’s idea. This is incorrect [3, 4]. Put simply, the myofunctional concept is ostensibly based on soft tissue effects (muscle stretch) to achieve correction, while Mew’s idea is ‘forward jaw growth’. But the Reviewers are correct that ‘forward’ growth of the jaws is not supported by the orthodontic literature [3-4, 5-6].
Moss’ functional matrix was a good start in understanding the developmental mechanisms involved in the precipitation of malocclusions, but it was incomplete since the technology was lacking, and teeth were omitted from his ideas. Moss talked about the ‘genomic thesis’ that Drs Proffit and Ackerman subscribe to. He talked about the ‘epigenetic antithesis’, which Drs Kahn and Ehrlich subscribe to. He talked about the ‘resolving synthesis’ that I used to formulate the Spatial Matrix hypothesis [7], which predicted issues such as obstructive sleep apnea that are currently being discussed.
References
1. Singh GD. Outdated definition. Brit. Dent. J. 203(4), 174, 2007.
2. Parsons TE, Downey CM, Jirik FR, Hallgrimsson B, Jamniczky HA. Mind the gap: genetic manipulation of basicranial growth within synchondroses modulates calvarial and facial shape in mice through epigenetic interactions. PLoS One. 2015;10(2).
3. Singh GD, Medina L, Hang WM. Soft tissue changes using Biobloc appliances: Geometric morphometrics. Int J Orthod. 20:29-34, 2009.
4. Singh GD, García AV, Hang WM. Evaluation of the posterior airway space following Biobloc therapy: Geometric morphometrics. Cranio 25(2): 84-89, 2007.
5. Singh GD and Clark WJ. Localization of mandibular changes in patients with Class II division 1 malocclusions treated using Twin Block appliances: finite-ele
6. Singh GD and Hodge MR. Bimaxillary morphometry in patients with Class II division 1 malocclusion treated with Twin Block appliances. Angle Orthod. 72(5), 402–409, 2002.ment modeling. Am J Orthod Dentofacial Orthop. 119(4), 419-425, 2001.
7. Singh GD. On Growth and Treatment: the Spatial Matrix hypothesis. In: Growth and treatment: A meeting of the minds. McNamara JA Jr (ed.) Vol 41, Craniofacial Growth Series, Ann Arbor, USA, 2004, 197-239.