by Felix Liao
In the image above, you can see a maxilla with significant crowding. In the image below, you can see Liao’s Sign indicating the same maxilla as being retruded. This combination results in a weak chin. The deep chin groove signals a low ceiling in the three-foot den,and a big double chin represents the tongue bursting beyond its habitat.
In this severe case, oral-appliance therapy worked as an assist to his CPAP device. His oxygen debt was so huge that it’s taken him five years to begin feeling better.
Want to Lose a Weak Chin or Double Chin? Mind Your Maxilla!
A double chin can result from obesity or from the tongue bulging beyond its confines inside a three-foot cage—or both. Normally, the mandible should fit into the maxilla like a foot into a shoe. A deficient maxilla starts a domino effect impacting the airway, facial appearance, and the whole body, often in combination with a retruded mandible..
A retruded maxilla shows up as a flat or a sunken midface in appearance, raising the risk of a retruded mandible and perpetuating snoring and OSA. It is also much harder to treat, with jaw surgery being an option in severe cases. That is why I recommend that children be evaluated by age eight to catch a retruded maxilla while the craniofacial skeleton is still quite malleable.
The height and depth of the orofacial region is assessed from the side. Is the profile protruded or retruded? Does the face round outward, or does it appear pulled back toward the airway?
Treatment for retrusion is protraction, or drawing the jaw forward. Protraction is done with either surgery or an oral face mask worn with oral appliances during sleep.
Jaw surgery (maxillo-mandibular advancement) to advance the maxilla and mandible has been reported as an effective option to treat OSA.(2) It can be useful in severe cases of obesity and severe skeletal malocclusion. Yet 99 percent of the time, the oral face mask works very well. Contrary to what you might think at first glance of the device, 90 percent of patients can sleep with the oral face mask without any problem.
A pair of rubber bands connect the upper oral appliance to the oral face mask.
How a Marvelous Maxilla Is a Missing Key to Optimal Health
49 percent of upper jaws are retruded, based on a study on children by Dr. James McNamara.(3) This is the start of a narrow airway behind the soft palate or tongue, ie, impaired mouth and pinched airway.
Unrecognized and untreated, children with retruded maxillae may well grow into adults with sleep apnea and all its medical, dental, and mental side effects. This may explain the prevalence of sleep apnea at a later age.
In adults, retruded maxilla is the structural source of a variety of physical features and unfavorable adaptations, including:
The white part of the eyes visible between the lower eyelids and the iris(4)
The outer corners of the eyes angling downward(5)
Flat cheekbones and receded midface
An excessively prominent or deviated nose
A flat or sunken upper lip in profile (Liao’s Sign)
A narrow and steep palate with little room for the tongue
Crowded lower and/or upper front teeth
Clicking, popping, or locking jaw joints (TMJ dysfunction)
Wrinkles around lips, saggy mouth, and deep facial creases
A weak chin and/or a double chin or bulge in front of the neck
A narrow airway
This retiree has fatigue, history of many crowns and root canals, declining memory, and back pain. She also has a deficient airway.
This college girl and a soccer player is heading toward the same medical-dental fate as the librarian.
Redeveloping Retruded Maxilla in Adults
A non-surgical treatment for a retruded maxilla is an oral face mask (OFM) worn during the hours of sleep. Imagine have your maxilla heading in the right direction while you sleep -- what can be better?!
A pair of rubber bands connect the OFM to a maxillary (upper) oral appliance provide a light forward stretch. This light stretch simulates a retruded maxilla to grow in the right direction to open up the airway.
Contrary the first glance, an oral face mask mask is easy to use, and predictably effective. Over 90% patients can sleep with it after a brief period of adjustment. Oral face mask shown below has been used in growing children for decades.(6) It’s almost never used in adults until now.
To confirm diagnosis of a retruded maxilla, mandible, or both, I use cephalometric analysis to show me what’s off with the “three-foot cage”, where, and by how much. Cephalometry is the geometric measurement of the teeth and jaws inside the craniofacial skeleton. It‘s like an architect’s blueprint of the house of the jaws, teeth, and tongue that also tells me if oral face mask is needed in each case.
I have used oral face mask routinely with upper jaw appliance in adults with good results in compliant patients. “Your compliance drives your treatment success” is my advice.
Evidence of Oral Face Mask’s Value
S.A., a very motivated CEO in his fifties, wore his oral face mask religiously for two years and gained 10 mm of height in his former three-foot cage. “Every millimeter I gain is a plus for my health,” S.A. said. “So why not get the most out of my treatment?!”
S.A.’s airway volume grew by 58 percent from faithfully wearing an oral face mask during sleep and oral appliance twelve to fifteen hours a day over two years. Cephalometrics show that OFM did reduce his maxilla retrusion by 10 mm over 2 years. Look for the change in the size of the yellow dot in the next two slides.
This evidence shows that “the earth is no longer flat” — that the maxilla can indeed be redeveloped and repositioned in 57 year-old with a seriously retruded maxilla.
The more retruded the maxilla, the more likely the airway obstruction behind the palate. The more retruded the maxilla, the more likely the mandible is retruded, and this has both medical and dental implications.
The more retruded the mandible is, and the more likely we will find the tongue clogging the airway. This can lead to snoring and a higher risk of sleep apnea with its many associated cardiovascular, cancer, and Alzheimer’s brain consequences. A 2008 Japanese study made a significant link between a retruded mandible and obstructive sleep apnea.(8)
Airway can be improved predictably, sleep can deepen naturally, and the body restarts with vigor, when a retruded maxilla is recognized and treated, as the case of S.A. shows.
Retruded Jaws: The Real Causes of TMJ Dysfunction that Almost No One Treats
Retruded maxilla and/or mandible come(s) with dental and TMJ (clicking, popping, locking jaw joints) troubles. TMJ Dysfunction (TMJD) is a syndrome covering the pains in the head, neck, face, shoulders, and back, and related mind-body-mouth distress is well documented.(7)
In my experience, TMJD is easily treated by identifying its anatomical source: an underdeveloped and/or retruded maxilla, a retruded mandible, or both. This has an added benefit: wider airway for superior sleep and natural health.
The mandible can even become entrapped—locked into a retruded position — by a deep overbite. With mandibular entrapment comes persistent aches and pains, fatigue, the global symptoms of TMJD, and major complications from teeth grinding, such as broken teeth, loosened dental work, and failed implants, and more.
Beside genetics, a retruded mandible has three developmental (epigenetic) causes:
An underdeveloped maxilla with crowded teeth and a narrow arch
A retruded maxilla resulting in a narrower airway behind the soft palate
A deep overbite, with the upper front teeth inclined toward the palate
Pinkie Test for TMJ and Mandibular Entrapment
To see if your TMJ/mandible is retruded, you can do a “pinkie” test.
Put your small fingers inside your ear openings with the finger pads facing forward. Feel for the jaw joints pushing against your finger pads when you bite your teeth together, and listen for clicking, popping, or grating sounds. Such sounds suggest entrapment of the lower jaw and a tongue that is pinching the
airway.
Next, repeat the same pinkie test, only bite your front teeth together instead. This simulates the protruded position of the jaw joints. If the clicking noise and the pushback go away, then one or both jaws may be retruded.
How to Reach Your Genetic Potential by Freeing Your Trapped Mandible
Freeing the mandible from its entrapment can be an effective way to redevelop the airway naturally and actualize genetic potential.
Lower jaw posture can influence gene expression. In a 2003 study, Dr. Fuentes measured gene activities in rats with one jaw joint induced into retrusion and the other into protrusion. She found less gene activity in the retruded jaw joint and more in the protruded joint.(9)
This means fuller genetic potential is actualized when the mandible is freed from entrapment. Conversely, living with mandibular retrusion means not reaching genetic potential in form, function, health, and life. This study was a huge inspiration to me.
Images courtesy of Dr. G. Dave Singh
Conclusion: The body can better heal itself when the jaws are positioned so the mandible is freed from entrapment, which in turn requires a fully developed maxilla.
Are your lower front teeth crowded? Going back to the maxilla as the shoe and the mandible as the foot analogy, that means your maxilla is underdeveloped in the “toe box,” or retruded in position.
Other surface signs of maxilla deficiency can include a weak chin, a deep chin cleft, double chin, abnormal head posture, and Liao’s Sign: a flat or curled upper lip in profile.
Holistic Mouth Bites
The maxilla is the centerpiece of the face and its development drives mandibular and airway development, or lack thereof.
Crowded lower front teeth is a clue that the upper jaw’s front end is underdeveloped.
Fuller genetic potential is better actualized when the mandible is freed from entrapment. Conversely, living with mandibular retrusion means a life of not reaching genetic potential.
Retruded maxilla can be treated in adults with a combination of oral appliances, and oral face mask appears to boost redevelopment in adults with impaired mouth and pinched airway.
Chapter Thirteen
The Telltale Tongue
There are no specific diseases; there are only specific-disease conditions.
– Florence Nightingale (attributed)
The tongue is a big, powerful, muscular organ inside the head, yet it has not received the attention it deserves. Its size, position, and habit matter greatly to maxilla development, orthodontic success, total health through airway and sleep, or initiating Impaired Mouth Syndrome.
Although the tongue is attached to the lower jaw, its parking spot is on the palate where it serves as a natural palate expander in children, doubling in size from birth to adulthood when it serves as a natural palatal retainer. During that time, oral-facial development can (and often does) go wrong, resulting in a three-foot cage.
Another prerequisite for a fully developed maxilla is the absence of a tongue-tie—an abnormal attachment of the tongue to the mandible that prevents full range of motion and agility. Medically, it’s known as a short lingual frenulum, and you might be surprised by its influence on total health.
Soft Tissues Shape the Skeleton and Your Face Is No Exception
Genetically, humans are coded for a wide-open airway inside a fully developed cranial skeleton with a full face on the outside and room inside for all thirty-two permanent teeth – yes, wisdom teeth included.
In craniofacial growth and development, it is the soft tissues that shape the bones. “According to Moss, the form of the facial skeleton is largely secondary and adaptive to surrounding soft tissues and functional spaces”, writes Dr. G.D. Singh in Epigenetic Orthodontics in Adults,(1)
Translated: the tongue helps grow its habitat space through normal functions such as suckling, swallowing in the first few months, and chewing and speaking after teeth come in. In the first months of life, the tongue milks the breast by trapping the nipple against the palate. This action is a powerful stimulus to develop the maxilla and craniofacial skeleton through the sutures that join all the skull bones into a head.
Tongue-tie can block this natural, gene-directed development as can habitual mouth breathing. Remember: The tongue participates in the vital function of swallowing 1,000 to 1,500 times a day, every day. This powerful, repetitive pattern can even undo daily chiropractic adjustments or oral-appliance work!
Underdevelopment (an impaired mouth and pinched airway) happens when growth is turned off prematurely by epigenetic factors. The genes are not fully expressed, and the jaw structures do not reach full potential.
In my mind, craniofacial redevelopment reaches full genetic potential when the lower front teeth are no longer crowded and the entire lower arch can fit into the arch peak-to-valley without jaw-joint clicking, popping, and deviations, and enough oral volume for the tongue to stay out of the airway 24/7.
Bad posture and bad bite inside impaired mouth may be connected -- see chapter 17
Childhood Origins of Impaired Mouth and How to Prevent Needless Suffering
Evidence that the tongue is a big player in OSA comes in part from research in pediatric sleep apnea. A 2015 study from Taiwan concluded that a short lingual frenulum (tongue-tie) “may lead to abnormal orofacial growth early in life, a risk factor for development of SDB [Sleep Disordered Breathing].”(2)
Correct muscle functions in chewing, breathing, swallowing, and mandibular rest posture favor the development of a Holistic Mouth. For example, the lips should be gently sealed and the jaws relaxed when the mouth is at rest and when sleeping.
Abnormal oral-facial muscle use, on the other hand, perpetuates muscle tension and promotes relapse after orthodontics. Swallowing should not be accompanied by a gurgling sound, tension lines around the mouth, or head-bobbing. That’s why treatment with Holistic Mouth Solutions includes more than just oral-appliance therapy—and why orofacial myofunctional therapy is important when indicated.
Oral-Facial Myofunctional
Myofunctional therapy is physical therapy for the tongue and all the orofacial muscles involved in swallowing and breathing. (Myo comes from the Greek word for muscle.) For this reason, it’s also known as orofacial myofunctional therapy (OMT). According to the Academy of Applied Myofunctional Sciences, OMT is done through “neurological re-education exercises to assist the normalization of the developing or developed craniofacial structures and function.”(3)
Dr. Christian Guilleminault, considered the father of pediatric sleep apnea, did a follow-up study on twenty-four children previously diagnosed with sleep-disordered breathing at ages three and a half to seven years and appropriately treated with tonsillectomy and orthodontics. Thirteen of the twenty-four did not complete myofunctional therapy. All thirteen had a recurrence of SDB (sleep disordered breathing) and mouth breathing during sleep while the eleven who completed myofunctional therapy did not. “This study illustrates the potential importance of myofunctional treatment as an adjunctive treatment [for children with SDB],” wrote Dr. Guilleminault.(4)
Why is myofunctional therapy needed in the first place? Tongue-tie, in varying degrees, is one big reason that is frequently overlooked in childhood.
Tongue-Tie: Baby Lucy’s Story
The tongue is a muscular organ capable of movement in all directions. A tongue-tie, or ankyloglossia, restricts the tongue to the floor of the mouth by a ligament called a lingual frenum (also called frenulum). The length and flexibility of a tongue’s frenum determines its resting posture.
Imagine the tongue on a short, stiff leash, preventing it from reaching the palate. This is what tongue-tie does. It can lead to excessive chin, as in the facial profile of a witch. Combined with habitual mouth breathing, it can lead to a long, narrow, “horsey” face with a pinched airway inside.
Tongue-tie effectively anchors the tongue to the floor of the mouth and keeps it from reaching the palate where it naturally stimulates maxilla development. A t
ongue-tie makes it hard for a baby to latch, leading to one frustrated baby and one exhausted new mom. Sixty-nine percent of lactation consultants believe tongue-tie in a newborn can interfere with breast-feeding.(5)
A severe tongue-tie can result in breast-feeding unless the tongue-tie is surgically released (revised). Here’s an email I received from a patient and mom to new baby Lucy:
We proceeded with the tongue-tie and lip-tie revision, as you had recommended. Lucy is recovering well, and I could tell an immediate difference in her latch. She’s still relearning how to use her tongue well, but I’m hopeful this will have a positive impact on her breast-feeding and her oral development. The whole family will see you soon.
At her last checkup and cleaning, Mom reported that Lucy had more than caught up with her weight.
Poor latch is one sign of tongue-tie, and feeding fatigue is another. Educating new moms about tongue-tie is important. Lucy is lucky to have had her tongue-tie diagnosed in the first few weeks of life. A new protocol was introduced in 2012 to evaluate tongue-tie in newborns relative to feeding fatigue, which is characterized by less than one hour between feedings, fewer sucks, and longer pauses between groups of sucking.(6)
Tongue-Tie Initiates Impaired Mouth
Adults suffering from an impaired mouth’s many oral-systemic symptoms often grew up with unrecognized tongue-tie, as well as things like bottle-feeding, pacifiers, poor dietary habits, stuffy nose, and habitual mouth breathing in their childhood. They simply did not have the benefit of a Holistic Mouth checkup while they were growing up.
Even mild to moderate tongue-tie can have dental consequences and subsequent snoring and sleep apnea. Varying degrees of tongue-tie are common among patients who come to see me for teeth grinding and related oral-systemic problems. This is the long shadow of unrecognized tongue-tie from childhood.