Dental Malocclusions can be severe or not even noticeable to the patient. The classification of dental malocclusion was first developed by Edward Angle around 1900. His three classes are based on the tooth relationships of the upper and lower jaw. Over the years other subclasses have been added. It is interesting to note that insurance may not provide benefits if the malocclusion is not severe enough to effect eating or talking. Image at right: (A), Normal occlusion; (B), Class I malocclusion; (C), Class II malocclusion; (D),Class III malocclusion. Note the position of the mesial cusp of the maxillary molar relative to the mandibular molar in each type of occlusion.
The main problem with this method of classification is that it only describes the relationship of the teeth and has nothing to do with the position of the teeth with respect to the skull, tongue, hard palate, soft palate, temporomandibular joints and especially the airway.
The profession of dentistry is moving beyond a focus on teeth while giving little ort no attention to the role that oral conditions impact on systemic health. The current hierarchy places the airway as the number one priority. What will treatment or lack of treatment do to the airway? Today more and more studies are showing that maxillary and mandibular retrusion, mouth-breathing and the lack of early intervention puts children at heightened risk for morbidity and mortality.
Early intervention to promote ideal nasal breathing by maxillary expansion, myo-functional training, treatment of allergy and sleep disorders is essential, even as early as 2-3 years of age. So much of our growth and development and brain maturation is completed by 6 years of age.
The stigma of ADHS and other learning disabilities is often made by kindergarten at age 6. We know from the recent article in the J of Pediatrics that many children with behavioral issues really have a sleep/breathing disorder. ADHD has been reversed by treatment of sleep disorders through adenotonsilectomy and palatal expansion therapy.
Airway obstruction in children is most often caused by enlarged tonsils and adenoids, well as constricted palates. Airway obstruction can be diagnosed as obstructive sleep apnea by overnight sleep studies (PSG) or home sleep studies. Due to poor nutrition, allergy and epigenetic factors children’s airways are frequently narrowed. Most children have bimaxillary retrusion even in class 1 normal occlusions. Most maxillas are retruded according to McNamara , and therefore the mandible is forced into a retruded posture with a retruded tongue base. Retruded maxillas are associated with retruded hard palates and retruded soft palates further obstructing the airway. The Angle classification exposes crucial flaw in orthodontic theory by basing occlusion on tooth-to-tooth relationship with no consideration of the airway. The result of orthodontic treatment can be perfectly aligned teeth and diminished airway.
Lack of early expansion, which may then be followed by the extraction of the four bicuspid teeth and the utilization of headgear, further constricts the airway and predisposes the child and adult to learning disability, ADHD, depression , fatigue and neurocognitive defects.
Orthodontic classification should be based on the airway and ideal skeletal potential. Dished in faces, narrow maxillas and closed airways with compressed TMJs can and should no longer be acceptable.
We need to be face focused, airway focused, TMJ focused, not tooth focused. The current Angle orthodontic classification puts undeserved importance on the teeth, often at the expense of the airway. Straight teeth are not necessary for survival but a sufficient airway day and night is. The hierarchy for survival and the ability to thrive is Airway , then proper nutrition , and oral structures that allows ideal sucking, swallowing and chewing and then lastly the occlusion.