Oral function

He suggests the possibility that the weakening of the oral cavity function with the aging is connected for locomotive syndrome by feebleness (Frailty) and the muscle attenuation (Sarcopenia) in the whole body while showing the mechanism of oral cavity functions such as infants, the data about the normal growth and obstacle of the oral function of the child and breathing or the deglutition from a fetus and proposes importance of the oral cavity function maintenance.
And he says that we need to consider how the dentist concerned with all any people regardless of age or sex from an infant to an elderly person through the treatment of the oral cavity should solve this problem.

　未病　ME-BYO　
The state that abnormality is not found even if examined, and a disease is not diagnosed, but it cannot be said that it is healthy either.


　　INDEX　　

What is the oral health?

We thought that the treatment of caries and periodontal disease was dental treatment, and the oral function was kept if the number of the teeth existed a lot until now.
However, the new problem to increase the risk of the life begins to appear when it was in a situation that a body does not move with leaving many teeth because the cleaning of the tooth is difficult. Besides, even if a tooth exists, an aspiration and the suffocation do not decrease, and apnea and sleep disorder during sleep are not solved.

Now, dentistry is thought to have to do a paradigm shift from Dental health to Oral health, Health of the whole body.

At such a point, the definition of the oral health of Mitsuharu Takeuchi (professor emeritus of Tokyo Dental College) captures the oral health widely and states that oral health is not only "there not being illness abnormality", but also “the normal growth" and "the display of the function".
Furthermore, he continues that when "the health of the dental oral cavity of the former two makes the main constituent and is not merely a thing called the prevention of the illness abnormality".
In other words "the normal growth of the oral cavity" and "the display of the oral cavity function" include the main constituent of the oral health, and it is in particular thought that to manage the growth of the chin oral cavity so that a mouth reserve function is shown enough, it prevents disease of oral cavity and abnormality of a form, the structure of the oral cavity and it is connected for the way of dentistry of ME-BYOU.

In addition, Kuniaki Otake who is my teacher says in his book; "Health means there is no disease, but also a person should be able to have adequate function. It is to become in condition to be able to show the role and the function that oral cavity has enough.

In other words he states, it is only a requirement that there is not a disease.

Now the dentistry worker is demanded that he arrests a person as a whole and comes to maintain living environment surrounding the person for the oral health.

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What is the oral function?

It is that balance of quality and the stomatognathic system of the oral function strongly influences dentition, occlusion that the malocclusion is accompanied by some kind of malfunctions by all means.
Therefore the acquisition of a favorable oral cavity function will bring upbringing of dentition, the occlusion and the prevention of the dentition anomaly of occlusion for an infant of the development period.

However, the cause that the oral function is acquired and cannot show is not clear really .
Because start time of the acquisition of the oral function is the child care period, we cannot judge a delicate border to keep between the growth patterns of the infants who continue growing normally and infants holding a problem.
Therefore, it may be said that it is very difficult to let the infant of the period of growth get an oral cavity function smoothly artificially.
As a result, it is thought that there is a difference in the quality of the oral function to all adults, and big influence appears when they became the elderly person.

The main oral function is eating, breathing, articulation, expression display and input of the sense information.
These functions strongly affect life support and the social nature as the human being.
Therefore to invite the drop of the oral function affects to independence of the everyday life of infants and an elderly person, a person requiring nursing care who are the life weak.

Thus, the acquisition of the oral cavity function that is favorable for the infant of the period of growth, and the maintenance, planning prompt recovery of the function to an elderly person is the important problem.
And this will cure ME-BYOU.

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What is the display of the oral function?

Not the viewpoint biological function (chewing, swallowing, breathing) and daily life function (articulation, the expression) that are a general oral function, judging from an anatomical viewpoint, as for the oral function, it is thought with three of the eating function (chewing, swallowing), breathing function and articulation function.

Because "cavity of pharynx" is cooperated and used , these functions cannot be acted at the same time.
The cranial position in the human trunk changed into it by Homo sapiens having become the vertical bipedalism in a process of the evolution, and expansion of the cavity of pharynx was produced, and soft palate and an epiglottis did detached room open.
Due to the closing and the resonance of the pharynx formed by the soft palate and the tongue occurred, the human being got mouth respiration and articulation called the new function in this way.
However, on the other hand, human being obtained the problem about crisis of the life called asphyxia and aspiration, habitual mouth breathing and apnea during sleep.

Therefore, mechanism of the oral functions judging from structure of the oral cavity of pharynx is to change these three functions, and the power to change these three functions is expected that "an oral function shows" .

reference

Generally, the animal does not let the respiratory tract clog up with a thing, and a passage of the air and a passage of the food adopts the grade separation system and do not have the aspiration.

On the other hand, the Homo sapiens takes the crossover point system in the face of a risk daringly though a grade separation is safer.
It enables a sound and a language in the Homo sapiens.
The Homo sapiens cannot speak words by nature and the throat of the baby is the same as a chimpanzee until about three months, and the passages drinking breathing and milk become separate and the baby sound a nose while drinking the breast and breathe.
When it is over three months, pharynx and an epiglottis begin to fall down with the development of the lower jaw and come to start the laughter and words from a mouth with the vocal cords.

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What is the mechanism of the oral function?

The oral function is regulated in response to "pressure".
In breathing and the starting words, it is coordinated by an aerodynamic element (the extensibility of the breathability of the nasal cavity, the lungs and the trachea, larynx air speed, the capacity of the oral cavity and pressure, swelling of lips).
At the time of the swallowing, it is adjusted by the pressure of the meal lump which is an element of the dietary behavior.
In the adjustment mechanism of these two, it is soft palate that plays a central role by coordinating the pressure with oral cavity on a border of the cavity of pharynx, and a swallowing function and a breathing function and a speaking function are changed instantly by the work of the soft palate.

The negative pressure formation of the oral cavity of pharynx is related to mechanism of the development and the acquisition of the oral function.
Maruyama reports the association between posture of the fetus and oral function as follows.
"Intraoral negative pressure increases, and lips closedown is facilitated, and it is possible for amniotic fluid deglutition easily when the fetus does posture forming a circle that the posture of the fetus in the uterus bent a neck forward, and the activity of the facial muscle is stable, and the development of functions such as suckling milk, swallowing, the nose breathing is promoted after birth."

In addition, Hayashi reports that the exercise that supports posture and human trunk by the crawling on all fours of the child face down for three months after birth states is important when an oral cavity function develops.

In other words the acquisition of the high quality oral cavity function cannot be expected if the negative pressure formation of oral cavity and the cavity of pharynx cannot be got in mechanism of the development of the oral function.
Therefore a human trunk supporting craniocervical part well is necessary, and it is necessary for the human trunk to form the negative pressure of oral cavity and the pharynx

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In the elderly person, when the muscular strength of the human trunk decreases, the head inclines above, and a neck grows, and the negative pressure formation of the oral cavity of pharynx becomes insufficient, and the pressure reception of pharynx and the oral cavity decreases, and the elderly person has a drop of a deglutition reflection and the cough reflex, and an aspiration becomes easy to occur.

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Actions to ME-BYO by dentistry

Power to surely eat

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Characteristic of the chewing motion 1.2
Half unconsciousness motion, Half self-regulation motion and rhythm movement

Four parts constituting chewing motion are controlled by the center, and the semiautomatic semiunconscious rhythm movement to be seen in chewing motion resembles a walking movement closely.

When we usually walk, we walk in response to a change of the ground while switching on/off the consciousness.
Similarly, we perform chewing motion while switching on/off the consciousness when food is in the mouth.

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Characteristic of the chewing motion 3
It is hard to do disuse atrophy.

When muscle power usually declines, control imperfection of a walk and the posture occurs and results in functional decline by the disuse atrophy.
However, exercise to adjust the balance with the muscle of the circumference to while constrictive adjustability of small distance and fast power to repeat the shrinkage and relaxation at a speed are demanded from the oral function while large number of muscles cooperate and taking the constrictive timing of the line does not need big muscle power.
As a result, disuse atrophy is hard to occur.

It is thought that it can continue using the muscle power required by the daily living activity of the oral cavity function in about 20-30%.
When it was less than this, it becomes the disuse atrophy, and muscle fatigue is easy to come out when it exceed this, and it is thought that it cannot work for a long time.

At the time of the conversation in particular, the muscle of a chin and a tongue and soft palate and the face repeats it at fast speed for long time and exercises.
However, even the long-time conversation is not tiring because of around 30% of the maximum muscle power.

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Characteristic of the chewing motion 4
A free motion degree is big.

Joint of the oral region is only temporomandibular joint.
Muscle will connect with muscle in one way or another without having joint.
It means that it is necessary to be active in a good balance while competing for plural muscles.
"Flexibility, extensibility and cooperation of the muscle" are necessary to show an oral function, and not to reduce the quality.
Therefore, sensitivity for "the pressure" that is the base of the oral function is high.

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Characteristic of the chewing motion 5
A limit and permission decide the exercise side and a range.

Mandibular movement and the tongue motion are the center of the chewing motion, and these exercise carries out most suitable activity according to a property and size of the food by the information from the sense organs of the oral cavity.
In addition, it works in 6 directions of anteroposterior, top and bottom, right and left, and it decides a direction and size and strength of the chewing motion.
A difference comes out to exercise on this occasion by receiving a limit and permission by facies occlusalis dentis forms and occlusion states and muscle power in the exercise range (dietary behavior is different between individuals).

Because it is difficult for patient oneself to recognize strength of a limit and the interference of the mandibular muvement, the instruction and the correction from a person of medical care are necessary.

In addition, the correction of the motion is possible by learning it under consciousness and can return it to the motion that is unconsciousness.
It is thought that it is important people is conscious, and to exercise so that smooth mandibular movement is always possible to every direction.

Power to eat safely

To eat safely is power to remove an alien substance in chewing and power to swallow safely.

[Power to remove an alien substance]
Food safety is said to be the pillar of of the food education, but the most appealed for things to eat safety.
Food safety for the dentistry person may be to let people get power to eat safely, not safety of food.

However, children who cannot look for the one small bone increase recently.
It is thought that the reason why alien substance exclusion of such a food is not possible is caused by the fact that a chewing function is low.
The information for the alien substance enters by the sense input from lower jaw, a tongue, lips, cheeks, soft palate by chewing motion, but, as for the elderly person, it is thought that alien substance exclusion ability falls because chewing motion decreases with aging.

In addition, it is not only taste to eat, but also the sense from temperature and pressure associated with the sense of touch, and the peculiar sense from joint and muscle and periodontal membrane are input.
The dietary behavior inputs the best sense stimulation in enhancing the cognitive function of the brain.

[Change of the swallowing and breathing]

Dietary behavior and dietary habits not to be disturbed

Because a body cannot fit current living environment (a meal in particular and physical activity)when the Homo sapiens evolved to a human being,, it is thought that the basic problem that present we have occurs.

At a glance, the death at birth and the death due to infectious disease decreased and seemed to obtain health and longevity without malnutrition except some countries and areas.
However, a chronic disease derived from life represented by obesity and metabolic syndrome spreads over the world.
In that way it is thought that our body cannot fit the society of modern convenient life and economy system.

I think that "optional judgement" in the meal and the body activity is necessary to cut off a vicious circle in this modern life, and to live for health.

After having chosen a meal among environment, a mouth determines whether we put it in the body.
The development of the oral cavity function and the growth of the form are indispensable to acquire dietary behavior and dietary habits to choose a meal in accord with a body.
However, we tended to give priority to nourishment when we thought about dietary behavior.

[Oral function and dietary behavior]

There are a lot of elements thinking about an oral function from dietary behavior.
Does the structure not to function which does chewing motion called deep overbite and open bite exist or not?
Do they pour it immediately because oral sensation is sensitive and feels a process of the meal lump formation called the chewing to be feel sick?
On the contrary, do they save it near intraoral front tooth forever, because they cannot swallow it?
Because they cannot chew without functioning of front tooth, do they stuff their mouth with much food?
Because they cannot chew only a soft and thin thing, do they stuff their mouth a lot?

In addition, in the case of "the child who do not eat much ”, who is easy to become the problem by the dietary behavior of infants , it is more likely to be deep overbite same as "the child who eats good ".

And oral cavity and the hypersensitivity of the pharynx sense are doubted.
Therefore it may lead to obesity by "pour and eat " as they grow up.

If it becomes an adult with dietary behavior from the infants period becoming a custom, and it is connected from obesity and metabolic syndrome to a chronic disease, it is important to let them acquire the dietary behavior that is normal as ME-BYO counter-plans of the chronic disease that assumed a meal prime cause, and it may be dentistry to carry the role.

Skill in the whole body motion development and the oral motion development

If all of the oral function mainly on eating is a motion function, I think that it is important to catch the development of the oral function as a part of development skills of whole body motion.
The oral emotion is located in the centrifugal rank in a whole body.
Therefore, to show the oral function, posture maintenance of a neck and the head which did it including a human trunk supporting the stable movement of the oral function is indispensable.

It is important to develop in order of "stable " " movable " " separation" to work on stable cooperation in the motion development of whole body.

The oral development skill is similar to it, too.
In other word, “stability” and “possible” of motion is important to switch from sucking motion to chewing motion.
In sucking motion, lingual muscle and orbicularis oris muscle, pharyngeal muscles are active all in one body to synchronize it for an opening and shutting movement of the mandibular.

In contrast, as for , the chewing motion works on reciprocal cooperation because the activity of the chin and the facial muscle of a tongue and lips, cheeks is enabled individual motion.

Stable sucking where a tongue was united with mandibular gives stability on mandibular, and the movement of the mandibular separates from this united motion.
Lips are open, and the activity of lips is low at sucking time, but lips closedown is necessary at the time of the chewing start.

The closedown of top and bottom lips enables the stable exercise of orbicularis oris muscle and buccinator muscle and, besides, creates the strong strangulation of the superior constrictor muscle at the time of the swallowing.
Thus, it is thought that lips closedown and the mobility of a mandible and the tongue are important to switch from sucking to chewing.

The ordering of exercise of mandible and tongue development follow a skill of the motion development of whole body.
The mobility develops with proximal stability as a base, and the development of the mandible develops with the skull and the head and the human trunk trunk as a base.

The tongue is more distal than mandible, and become the finger-tip when compare it to a hand.
When a tongue motion function decreases and became unstable, at first we confirm the stability of the mandible which is the higher motion, and it becomes more important to confirm the stability of the skull (posture) , the neck sequentially.

The oral function and sleep

It is known widely that the retrusion of the mandible lets the respiratory tract become constricted, and leads to sleeping breathing disorder.
However, the apneic cause during sleep of Japanese is said to be 50% of soft tissue types, skeleton type 10%, mixed type 30% and we knows that the problem of the soft tissue is big rather than the reason why only the retrusion of the mandible leads to a sleep disorder.

If the quality of the combination, cooperation campaign of four parts (mandible, lips, cheeks, tongue, soft palate) forming an oral function is low, it influence the individual quality and a form of dentition and cause the retrusion of the mandible and cause a sleep disorder.

Furthermore, the break of the posture by the physical strength drop of the elderly person causes a drop of the negative pressure of pharynx and the oral cavity, and the larynx descent by the aging worsens the interlocking movement of soft palate and the epiglottis and lets mandible retreat.

The deep overbite is improved by letting the infant of the deep overbite that lower jaw retreats and small walk every day.
From this, I think that the walking movement is effective in the elderly person with the retrusion tendency of mandible.

Risk of the mouth respiration

The mouth respiration is the function that is got because an oral cavity function was started at the time of birth, and the premature infant of viviparous 32 weeks causes Apnea by rhinostenosis cold without it being possible for mouth respiration.
The switch function that the newborn baby after viviparous 36 weeks performs mouth respiration at the time of nasal blockage is got.
Mouth respiration is got by receiving appropriate pressure resistance in oral cavity and the pharynx by repetition of sucking.
Because a change of nose breathing and the mouth respiration became possible, the change of breathing and the deglutition is stable.

Generally, the cause of the mouth respiration is regarded as lips dysraphism, but the mechanism of switch from nose breathing to mouth respiration works when the fauces closedown that works to maintain internal pressure of the cavity of pharynx as posterior oral sealing failed.
If the coherence of soft palate and the tongue is steady, nose breathing is maintained no matter how much by rhinostenosis even if nasal cavity ventilation resistance rises.
However, even if there is little degree of the rhinostenosis, the fauces closedown is broken if the coherence of soft palate and the tongue is weak, and the breathing air invades it in oral cavity easily and makes the mandible of a backward turn and the tongue of the low position, and it makes paths of breathing in oral cavity and destroy lips closedown (anterior oral sealing), and mouth respiration is started.

In other words, the fauces closedown by the coherence of soft palate and the tongue at the time of the nose breathing is important with lips closedown.

Becoming the custom of the mouth respiration does not only cause a problem such as dry mouth and the bad breath, and is more likely to make a chronic lesion to the oral cavity and pharynx.

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Only after the oral function that is essential for the maintenance of human life and the social existence is obtained enough, the surprising effects of saliva will be shown.

Saliva & Flora