The MEAW Technique (Multiloop Edgewise Archwire) is an orthognatic technique, which aims at aligning, in the most harmonious way, the jaw with the upper arch in the temporomandibular joint. This technique was developed early in the 1970s to prevent orthodontic relapse, which is the tendency for teeth to return to their pre-treatment position. As a matter of fact, after the treatment the patient’s teeth often crowded again in a short amount of time, even though the patient had undergone years of treatment and the dentist had created sufficient space in the arch by performing tooth (mostly premolars) extractions.
Why did teeth relapse? Was the therapeutic decision "wrong"?
Bolton Analysis is a tooth analysis, which was and is still used to quantify the space required to align teeth in maxillary and mandibular arches. This space wasn’t thought to be modifiable before the development of the MEAW Technique.
Child therapies often use removable braces to create the space necessary for teeth to easily fit in the mouth.
The MEAW Technique allows to align the teeth considering the arch from a static viewpoint.
In order to use the MEAW Technique, the facial growth must be interpreted as the result of genetic determinants which manifest themselves in specific facial features and of the masticatory forces that shape the structure of bones and their position. Generally, if the patient’s jaw is too far forward or too far back, it does not necessarily need to be treated with surgeries such as jaw reduction or advancement. The disorder may be treated with mandibular repositioning, which varies the inclination of the occlusal plane using muscle vectors and pointing them at will, so that the jaw can rotate backwards or forwards.
The MEAW Technique allows to modify the inclination of the occlusal plane and, with the help of light and short intermaxillary elastics, to steer forward or backward the rotation as well as the translation of the jaw.
Since MEAW Technique is not only focused on the alignment of the teeth, it is considered not just an orthodontic, but primarily an orthognatic technique.
When there is not sufficient space in the posterior part of the mouth, the wisdom teeth that have caused tooth overcrowding and jaw misalignment must be removed. The MEAW Technique will this way align the teeth in the most harmonious way in the temporomandibular joint, preventing them from going back to their original crowded position.
Short history of the MEAW Technique
The MEAW Technique was introduced in Boston in the mid-1970s by Dr. Young H. Kim.
The Korean doctor developed this technique to correct the anterior open bite of his Asian patients, who often presented with this type of malocclusion.
It was and it is still believed that this disorder could be cured only with surgery.
Dr. Young H. Kim was able to close open bites using a wire (MEAW) oriented as it appears in the pictures below.
At the time, this technique was used only to correct dental problems. It was Professor Sadao Sato who further developed the Meaw technique and extended its application to treat non dental problems.
In those years, Professor Sadao Sato had found the terminal hinge axis of the jaw using the SAM mechanical axiograph, which in this case wasn’t used for "dental" purposes. He then placed an eccentric stylus at the terminal rotation axis to measure the amount of rotation connected to the mandibular translation movement, inventing the Ghirrbach - Gamma Condilograph together with Professor R. Slavicek.
The instant center of rotation gained this way in clinical relevance.
The collaboration between two icons in the field of odontostomatology, meaning Prof. R. Slavicek, whose clinical approach is based on reconstruction, and Prof. S. Sato, who has an orthognatic clinical approach, led to the critical review of therapeutic procedures used to treat dysfunctional pain caused by TMJ disorders. In the 1970s these procedures allowed for the first time the TMJ disc recapture and its consequential repositioning.
With the MEAW Technique (Prof. S. Sato), joint therapy evolved in "Craniofacial Complex Dynamic" (1991) developing at the same time an aetiological approach: it did not involve only the TMJ disc recapture, but also the craniomandibular repositioning.