The bones that make up the hard palate also make up the orbit, the eye socket. The maxillary and palatine bones make up the hard palate and also form the floor of the orbit. With an interest in treating the jaw and eyes, I have recently had a curiosity in understanding how tongue thrusting (AKA- reverse or immature swallow) reshapes the hard palate over time and could ultimately affect the eyes.
Recently listening to a lecture by Dr. Holly Baller at NEO Smiles (www.neo-smiles.com), she was pointing out a case study about a child who after palate expansion had improvement in vision. So it brought me back to thinking, “what is the connection between swallowing and vision?”
I have observed that many of my patients had their palatine bones jammed against the maxillary bones. The palatine bones make up the posterior (back) portion of the hard palate and are often compressed against the maxillary bones that make up anterior (front) portion of the hard palate.
They are often so compressed that rather than being smooth at the suture, the suture is “bumpy” becoming easily palpable. The palatine bones are drawn down forming what feels like ridge. After decompressing them, the suture will often be smooth again.
I have also observed that decompressing the palatine bones off of the maxillary bones will produce an immediate change in the patient’s face. When jammed, the maxillary bones will be stuck in what is called a cranial extension strain.
This results in the maxillary bones being more pointed at the midline in the face. After decompressing the bones, the maxillary bones are palpably flatter as they move into cranial flexion. Besides affecting the face, it will also have an effect on the shape of the orbit. That is why I teach a palatine release in An Osteopathic Approach to the Eyes online course.
How do the palatines get compressed forward the the basic motion through the mouth is towards the back for swallowing? Food and saliva is drawn to the back of the mouth during swallowing. So to understand the hypothesized mechanism of how swallowing will reshape the hard palate, we need a basic understanding of what takes place in swallowing in a normal situation and with tongue thrusters:
Brief Overview of Normal Swallowing:
At rest, the tongue blade should rest on the roof of the mouth. This is its natural position. During a normal swallow, the blade of the tongue rests on the roof of the mouth pushes up as the tongue contracts. The posterior (back) portion of the tongue will then rise and come back down. This is an oversimplification but covers the basic motion necessary to understand what we will talk about. We will come back to this later. Now let’s review what happens during a swallow of a tongue thruster.
Brief Overview of Tongue Thrusting
During swallowing, tongue thrusters push their tongue forward rather than up against the roof of their mouth. They push their tongue against the back of their incisors, front teeth. In this case, the back of the tongue slides forward during swallowing pushes on the incisors. There can be multiple reasons one does not swallow correctly including tongue ties (ankyloglossia), soft tissue tensions, and behavioral (some never learned to use their tongue correctly).
Tongue thrusters are common and often have characteristics that include a narrow and arched hard palate. This has an effect on their airway often producing mouth breathers and can lead to problems such as sleep apnea. One thing I have noticed in my work, is that tongue thrusters also have the palatine bones compressed into the maxillary bones. I’ve been trying to understand why the palatine bones are so often compressed into the maxillary bones.
The Proposed Mechanism
It finally dawned on me recently that the jamming of the palatine bones into the maxillary bone is specifically a result of tongue thrusting. The tongue is actually not one muscle but made up of many muscles. One muscle that makes up the tongue is called the “palatoglossus.”
The palatoglossus fibers are towards the back of the tongue. From the tongue, the fibers go up the side of your mouth to the posterior (back) aspect of the hard palate into connective tissue there. This is where the palatine bones are. When the palatoglossus contracts, it pulls the tongue lifting it towards the roof of the mouth during swallowing.
During a normal (correct swallow), the palatoglossus brings the back of the tongue up. Simultaneously at the other end, the contraction of palatoglossus muscles will spread the palatine bones and part of the maxillary bones apart at the midline. This helps self-correct and prevent midline compression.
Midline compression will lead to a high arch and narrowing in the palate. Tongue thrusters do not have a swallow that decompresses the midline suture. Furthermore, when the tongue moves forward it changes the angle of the palatoglossus. This is how I think the tongue compresses the palatine bones.
After the tongue slides forward, the palatoglossus contracts to bring the tongue towards the roof of the mouth, it will pull the palatine bones forward and jam them into the maxillary bones. So apart from from pushing their teeth forward with the tip of their tongue and narrowing their palate that way, the tongue thrusters are jamming their palatine bones forward each time they swallow.
Other Ways the Eyes Are Affected By Improper Swallowing
By drawing the palatine bones forward, there is another main player directly affected, the sphenoid bone. The sphenoid is a butterfly shaped bone that forms the back of the eye socket. Most muscles that move the eye, extraocular muscles, attach onto a cartilaginous ring that is attached to the sphenoid. Nerves entering the eye socket from the head pass through the sphenoid.
Interestingly, the sphenoid has projections, called the pterygoid processes, down into the mouth that are articulate with the back of the palatine bones. The articulation between them is called the pterygopalatine suture. The palatine bones also have another portion that directly articulates with the sphenoid elsewhere called the sphenoidal process.
When the palatine bones are drawn forward, the pterygoid processes are also drawn forward. This rotates the sphenoid and can jam it into a cranial extension pattern. Now the sphenoid is not as adaptable and that may have an effect on the ability of the extraocular muscles to function. But this is not all…
Generally with a high arch, not only is the palate narrow, but there is also a large ridge splitting the palate from left to right along the midline. This ridge is produced by pushing down from above. It makes the hard palate more like the letter “m.” A bone called the vomer sits on top of the suture between maxillary bones along the midline. It helps make up the septum of the nasal cavity. As the arch of the palate raises, the vomer will push down the maxillary bones from above along the midline suture.
The vomer and the other bones that are thin and more delicate make up the septum. They then can get compressed by the much stronger bones from above and below. These bones are pliable and so will bend to one side or another producing a deviated septum. This will further compromise the airway making breathing through the nose more difficult as there is less space for air. The vomer articulates with a bone called the ethmoid and also the sphenoid.
Pushing the vomer up then, can further restrict proper function of the sphenoid and ethmoid. Both are bones that make up the orbit. One more important point to make is that many of the bones that we have talked about, the maxillary bones, sphenoid, and ethmoid also have sinus cavities.
By being jammed up, it has been my observation that they are then less able to drain properly and can cause sinus problems further compromising the nasal passage way forcing one to be more of a mouth breather.
Correctly Placing the Tongue Can Be Self-Correcting
When the tongue is resting relaxed correctly against the roof of the mouth, it makes a subtle self correcting motion. During cranial and respiratory inhalation, the jaw moves upward closing slightly. When this happens, the tongue subtly pushes up and the intrinsic muscles of the tongue widen spreading the palate apart. During exhalation, the opposite happens. This motion can be enhanced to amplify this self-correcting process.
So What’s the Next Step?
If you find that you or your patients are tongue thrusters, have a high arching palate, and/or are a mouth breather, you may be wondering what you can do about it.
First of all, I would recommend finding a qualified osteopathic physician that practices cranial osteopathy. Their role would be to help free up compressions in the skull, including the eye sockets, and other places that could be contributing. However, I would not recommend solely doing that because freeing up the compressions will accomplish little if you continue to use your tongue incorrectly.
At the very least, I would recommend adding an oral myofunctional therapist onto your team. Two good ones that I have collaborated with are Sandra Coulson here in Denver and Dana Hockenbury when I was in New York City. They are the ones who will go in-depth in evaluating how well one is swallowing and recommend an exercise program to retrain the tongue to function correctly during swallowing.
Dr. Baller and her team at Neo Smiles are pioneering newer palate expanding technology for pediatric patients and her colleague, Dr. Kent Lauson is doing the same with adult patients. They have patients from around the world and I feel their work better complements the osteopathic approach than the approach of many orthodontists. I would recommend contacting them to learn more.
Another option is finding someone who works with ALF (alternative lightwire functionals) appliances (http://www.alforthodontics.com).
If vision is also an issue, vision therapy by a behavioral optometrist may also complete the whole picture.
It is important to understand that this is a long term process but can definitely be a worthwhile endeavor for anyone looking to improve their health.
In the Eye Self-Help Secrets and Stop Tongue Thrust (coming soon) online courses, there are further self-help exercises one can do to themselves. At the very least, this is a great place if you don’t have access to any of the above.