IDEA

The primary focus in most orthodontic treatment is towards the teeth and their articulation. Unfortunately, function is not
the main concern. A proper diagnosis and treatment plan, in regards to the function of themasticatory system, is necessary
prior to any occlusal reconstruction. Based on functional analysis, there are many cases which should avoid tooth
extraction and surgical intervention. It is very important to characterize the malocclusion and to understand the role of
occlusion in order to make a correct diagnosis and treatment plan.

Non-surgical treatment of Class III malocclusion using MEAW mechanics
Observations of skeletal Class III malocclusions showed that the continuous forward displacement of the mandible was
associated with super version of upper and lower molars caused by the posterior discrepancy. Based on these findings,
it should be emphasized that the predominant orthodontic treatment objective in the correction of skeletal Class III
malocclusion is primarily to eliminate posterior discrepancy and reconstruct the occlusal planes. Correcting the
anteroposterior deviation of the dento-alveolar complex is necessary, but controlling the vertical relationship of
dento-alveolar complex is more important.

Problems involved in Class II malocclusions associated with craniomandibular disorder and their treatment
modality
The temporomandibular joint is one of the most essential elements of the craniomandibular system (CMS). It consists
mainly of interrelated structures such as the articular disc, ligaments, retroarticular connective tissue and muscles. The
CMS has long been considered to have a close relationship with the neuromuscular system (NMS) and the articulation
of the teeth (occlusion). Any alteration or significant change in the harmony of this dynamic system will greatly influence
all the dental, skeletal and facial configurations. Among the various types of malocclusion, hyperdivergent Class II
malocclusion is one of the most difficult cases due to diagnostic difficulties in determining the requirement for extraction
and what type of force system to apply in addition to a high frequency of disorder of the craniomandibular system. Our
study (Eur. J Ortho. 18:27, 1996) indicated the steep cant of the posterior occlusal plane correlated with backward rotation
of the mandible. This may also contribute to the development of craniomandibular dysfunction. Therefore, the control
of the vertical dimension of the posterior teeth is extremely important in treatment of hyperdivergent type of Class II
malocclusion.

Occlusal Plane and Malocclusion
Growth of the craniofacial structures is dependent upon the principles of occlusal plane and mandibular adaptation. Our
studies had indicated that the steep cant of the posterior occlusal plane induces a backward rotation of the mandible and
a forward adaptation of the jaw is readily observed on those having a flat plane of occlusion. The development of
skeletal malocclusions such as Class II, Class III an MLD cases are clearly dictated by their respective occlusal plane
configurations. This is because the neuromuscular system adapts to the function of articulation followed by skeletal
adaptation. Therefore, the control of the vertical dimension of the posterior teeth is necessary in the treatment of
malocclusions.