Professor John Mew, born in 1928, is  a dentist, researcher, orthodontist as well as an anthropologist. His father was a dentist from whom he developed his interest in dentistry. His lateral-thinking mind allowed him to question whether the causes of malocclusion were genetic or influenced by environmental factors and he actually provided answers.  

Figure 1 – Professor John Mew.

In 1965, he became an orthodontist after being qualified as Maxillofacial surgeon in 1953. He found quite perplexing how the aim of corrective jaw surgery was (and still is) to bring the maxilla and mandible forward (as can be seen in the example of Figure 2), while orthodontics was actually further receding the maxilla by extracting teeth (usually the upper premolars, as in the case of Figure 3).

Figure 2 – Orthognathic surgery results: notice how the maxilla and mandible have been moved up and forward by the procedure. (From [4])
Figure 3 – Orthodontics treatment that reckoned on teeth extraction: notice how his face has flattened and grown vertical. (From [5])
His father was already a visionary, performing palate expansion at a time where teeth extraction was the routine procedure in orthodontics. By reviewing his father’s patients records, John Mew found interesting how after-treatment of palate expansions were with three possible outcomes:

  1. Either the palate was relapsing, narrowing again.
  2. Or the expansion had a stable results.
  3. Or, most surprisingly, some palates were continuing to expand even after appliances were removed.

It was his spirit of observation and his will to find the truth that allowed him to set the ‘Tropic Premise’ in 1958: the ideal development of the jaws and teeth is dependent on correct oral posture with the tongue resting on the palate, the lips sealed and the teeth in light contact.

He understood that malocclusion was a ‘Postural Deformity’ caused by modern lifestyle. Furthermore, he was able to realize that malocclusion was just a symptom of something bigger: poor craniofacial development. He saw that there were two different types of facial growth (Figure 4):

  1. Horizontal growth: the face grows up and forward.
  2. Vertical growth: the face grows down and backward.
Figure 4 – The two different facial growth patterns. On the left, horizontal facial growth, with maxilla that is up and forward. On the right, vertical facial growth, with maxilla that is down and backward.

He found out that malocclusion was present only in those individuals with a vertical facial growth, affecting also the facial shape, neck posture and airways. It was under these considerations that he founded the London School of Facial Orthotropics and developed the Bioblock Therapy [1].

His ‘Tropic Premise’ can be seen as an application of the Wolff’s Law and it found confirmation from studies of dentist Egil Peter Harvold: during the 1960s, he performed several experiments on monkeys, in which he induced mouth-breathing in the animals by obstructing the nasal passages [2,3]. Mouth-breathing affected oral posture, with animals lowering the mandible and the tongue, that led to vertical facial growth and malocclusion.

However, the biggest confirmation for the ‘Tropic Premise’ came from John Mew’s patients: many of them were suggested to have surgery, but they were successfully treated by him thanks to appliances aimed to restore correct oral posture. Some of his magnificent results can be admired from Figure 5 to 16.

Figure 5 – Female Chinese child: despite the little change in the occlusion, notice the big change in facial development.
Figure 6 – Paula had an overjet treated with Orthotropics. Notice her facial changes, particularly in the cheekbones and labial areas.
Figure 7 – Shay had an overjet treated with Orthotropics. Notice the differences in the craniofacial development, especially in the cheekbones and labial areas.
Figure 8 – Before and after vertical and horizontal growth of same child.
Figure 9 – Underdeveloped jaw of Charlotte. She was waiting for surgery, but she has been successfully treated with Orthotropics, obtaining remarkably facial changes.
Figure 10 – Zoe’s Orthotropics case: restoring a correct tongue and closed-mouth posture implies maxilla remodeling. As a consequence, malocclusion is corrected.
Figure 11 – Cary is an adult case: even if more difficult since bones take more time to remodel, her facial changes are astonishing.
Figure 12 – Treated case with Orthotropics. Notice the bony differences in the face pattern, involving then eyes, nose, lips, cheekbones. Note the mandible does not change length but angulation, with changes occurring in the maxillary position and shape.
Figure 13 – Mouth-breathing is detrimental for individual’s health. When proper nasal breathing is restored, together with proper tongue and mouth posture, the result is horizontal growth of the maxilla.
Figure 14 – Forces coming from correct tongue and mouth posture remodel the maxilla forward and horizontally. The teeth then find larger space, resolving the malocclusion problem.
Figure 15 – Case of Micrognathism, where the jaw is undersized. She was told that surgery was required. She was instead treated by John Mew, with his philosophy  of treatment, where tongue posture has an essential role.
Figure 16 – Andrew’s case: the aim of Orthotropics is to move both jaws forward by mean of forces coming from proper tongue and mouth posture. The malocclusion is then resolved as a consequences of the bony changes.

John Mew has put a milestones in understanding the causes of malocclusion. His pursuit of the truth not only set him questioning common orthodontics practices of his time, but also spur him in creating a new philosophy of treatment for facial growth. He always used to said “There is a reason for everything“. And well, he is right!


[1] Mew, John. “Bioblock therapy.” American journal of orthodontics 76.1 (1979): 29-50.

[2] Harvold, Egil P., et al. “Primate experiments on oral respiration.” American journal of orthodontics 79.4 (1981): 359-372.

[3] Tomer, Britta S., and Egil P. Harvold. “Primate experiments on mandibular growth direction.” American journal of orthodontics82.2 (1982): 114-119.

Other websites

[4] Double Jaw Orthognathic  Surgery, by Dr. Antipov

[5] How to stop this happening to your children, John Mew Orthotropics