If some people have problems breathing through their nose, one reason behind this could be an underdeveloped/ narrow upper jaw (maxilla). As the maxilla is basically the floor of the nasal cavity and airway space, underdevelopment and narrowness in it can cause the airway to be constricted, resulting in impaired nasal breathing.
http://www.westonaprice.org/dentistry/mental-or-dental
Airway Obstruction
The most serious consequence of under development of the maxilla is airway obstruction and mouth breathing. Eighty five percent of the nasal airway is made up of the maxilla, which provides the floor of the nasal cavity and houses all of the nasal sinuses typically referred to as the sinus cavities. Therefore, an individual with a narrow or improperly formed maxilla will have extremely narrow nasal passages, which limit flow of air and breathing capabilities, and will thus experience difficulty in having proper sinus health and drainage.
It is an important fact that the soft tissues develop to their genetic size, even when the bones do not! You might think of the head as a box that must house all of the structures that the genetic code needs to express and that will develop, but lack of proper dimensions to the cranial bones and the cranial cavity causes overcrowding, overlapping or deviation of some soft tissue areas. This can be illustrated by the example of overpacking a suitcase.
Almost invariably a narrow or under-developed maxilla can cause the effect of holding back the lower jaw or the mandible. This improper positioning of the mandible and its inherent retrusion causes a lack of physical and physiological space for the tongue and the pharyngeal tissues, which again will provide an impedance to the airways, causing breathing difficulties and lowered oxygen uptake by all of the tissues.
It appears that one doesn't necessarily have to have ”crooked” teeth for the maxilla to be underdeveloped:
http://www.westonaprice.org/dentistry/mental-or-dental
The maxilla viewed from underneath. Note the narrow palate in this illustration.
It seems it has been realised that by using very light forces, the maxilla and the part of the lower jaw (mandible) where the teeth reside, can be developed to their full potential, even in adults. This seems to be due to these bony areas being of the type of bone, which’s form and shape is affected rather by function, and not by genes. Thus they do not lose their ability to be ”shaped” by functional dental appliances even in an adult age:
http://www.tripleolab.com/appliances.html (click "Williams")
There is a great deal of controversy within the profession as to the success or failure of arch development, sometimes mistakenly referred to as arch expansion. It is this author’s opinion that this subject is well addressed in the text by Enlow and Hans entitled “Essentials of Facial Growth” published by Saunders, ISBN 0-7216-6106-8.
The following observations are clearly stated in this text:
1. The body of the maxilla, as well as the dental alveolar base upon the maxilla, is comprised of dermal bone which has developed from the ectoderm. Dermal bone growth is primarily driven by function, not by genes.
2. The body of the mandible is comprised of chondral bone which has developed from the mesoderm. Chondral bone growth is primarily driven by genes, not by function.
3. The dental alveolar base upon the mandible is dermal bone and thus effected by function not by genes.
These concepts form the foundation of functional orthopedic and orthodontic therapy. They also provide the clinician with the insight to diagnose and treat growth related malocclusions.
Some telling pictures from
http://www.icnr.com/cs/cs_05.html
Maxilla before treatment:
After treatment:
Weston A. Price noticed that the primitive peoples he researched around the globe did not have malocclusions, and concluded that the improper diet, etc. of the modern world must be behind the phenomenon. As the shape of maxilla is formed by function, improper activity of the tongue plays a major part too.
http://www.westonaprice.org/dentistry/mental-or-dental
The most important orthodontic appliance that you all have and carry with you twenty-four hours a day is your tongue. People who breathe through their nose also normally have a tongue that postures up into the maxilla. When the tongue sits right up behind the front teeth, it is maintaining the shape of the maxilla every time you swallow. Every time the proper tongue swallow motion takes place it spreads up against maxilla, activating it and contributing to that little cranial motion, that cranial pumping that we discussed earlier. Individuals who breathe through their mouths have a lower tongue posture and the maxilla does not receive the stimulation from the tongue that it should.
A child developes an incorrect function of the tongue due to e.g. allergies (leading to mouth breathing), thumb sucking, etc..
The maxilla and occlusion are then misformed, and the position of the tongue is misplaced: a visciuos cycle of sorts is formed.
Curiously, nursing seems to be done in a vertical position with aboriginal people who live in natural conditions: here the swallowing and function of the tongue work properly. Nursing done in a horizontal position (as is advised to be done currently) on the other hand provokes incorrect swallowing and function of the tongue. Air is also being swallowed along milk, bringing up the need for burping. (I read this some time ago, sorry I am unable to provide a link.)
Interestingly, along with impaired nasal breathing, there are other disadvantages due to insufficiently developed maxilla:
http://www.westonaprice.org/dentistry/mental-or-dental
The TMJ and the Lower Jaw
When we look at the skull from the profile view we observe the temporo-mandibular joint, the TMJ. Most joints will go through normal hinge motion, and some of them like the shoulder and hip joint will have a rotational motion that is more complex. However, in these joints, the two bony members stay in contact with one another throughout the motion of the joint. The TMJ is unique in that it is designed to provide both hinging and sliding motion. In order to accomplish this compound hinge-and-sliding movement, the TMJ has a disc that slides in concert with the lower jaw or mandible. When the lower jaw is not positioned forward enough, the TM Joints do not develop very well, and the discs can get jammed behind or in front of the joint. They can even become perforated and cause some of the "clicks and pops" that can be heard when people open and close their mouths. Immediately behind the TM Joints we also have the ear canals and important vascular and neurological structures, which can become impinged upon as well.
A video of normal TM joint:
http://www.youtube.com/watch?v=fyHGOOhxHGs
A ”clicking” TM joint:
http://www.youtube.com/watch?v=KjB01-UIDYc
I have understood, that by treating the underdevelopment of the maxilla and dental arches (with the functional orthopedic/ orthodontic therapy mentioned above), joint pain and other related ailments can be improved (along with improved nasal breathing).
It seems that this type of treatment is not in the mainstream yet (from the above quote: ”There is a great deal of controversy within the profession as to the success or failure of arch development,”). However there appear to be a good amount of dentists practising the functional approach worldwide.
More information on the subject:
www.cfoo.com
www.iaortho.org
www.smilepage.com
www.tmjstack.com
www.tripleodentallabs.com/patient_info.htm
Sorry for the length of the post and going off topic as well, perhaps the moderators can revise a separate thread if appropriate :)
