Posturo-occlusal concept

What is the posturo-occlusal concept?

The posturo-occlusal or posturo-dental concept was developed in 1995 to bring out the primordial role of dental occlusion in the postural general equilibrium of the individual.

With the posturo-occlusal concept, for the first time, dental occlusion was no longer only examined and understood in relation to dental contacts or in a dento-dental setting, but through the individual as a whole.

This global vision, proposed as early as 1989, was largely ignored by the dental community because it clashed with the academic consensus and challenged preconceived ideas.

It was not better accepted by the posturological world which, at best, did not understand the relationship between posture and dental occlusion and, at worst, saw a new speaker disturbing this already very complex discipline.

Dental problems may be causing your postural problems

Rhône Dental Clinic adapts to the most demanding schedules and to the private requirements of each patient. We guarantee you a strict punctuality and offer an emergency service if necessary.

Purpose of dental posturology

Traditionally, posturology is the study of the standing man through his three main sensors: the eye, the vestibule and the foot.
For us, posturology is first and foremost a common, unified and multidisciplinary framework in which different health professionals are involved: doctors, ENT specialists, ophthalmologists, chiropodists, physiotherapists and dentists.

Posturology has brought rules and standards that have made the clinical examination more rigorous and objective. It has made it possible to objectify morphostatic modifications of patients during malocclusions and during modifications of the occlusion.

Our approach thus aims at a twofold objective:

demonstrate the role of occlusion in posture
to diagnose occlusal pathologies in postural deficits

1. The cranial concept of posture

The bipedalism and verticality that characterize hominization are the result of a slow phylogenetic and ontogenetic evolution. The standing man is the result of a cerebral evolution, a brain function.
The spherical cranial shape corresponding to an orthognathic cranio-mandibular relationship appears to be a criterion of optimal verticality.

At the same time, the eye sensor becomes the main postural referential in humans in addition to the inner ear, the feet and the skin.

In the same way, our immersion as well as our communication in the world are today more visual, than noisy, auditory or tactile.
These facts have led us to propose a cranial concept of posture (1). For us, posture can be summed up as a head stabilised in space in relation to the visual axis, the axis of the gaze.

The eye provides the reference frame necessary for the execution of the movement; skiers and riders have surely already experienced it (5). This postural strategy for stabilising the head is almost constant throughout an individual's lifetime.
The work of Amblard and Assaiante confirms that only children up to the age of 6 years use a strategy of stabilising the trunk in space.

What is remarkable and extraordinary for dentists is that the visual or labyrintho-visual plan is Frankfurt's plan. This means that there can be no occlusion without a postural reference to the Frankfurt plane, since the teeth belong to the skull.

The facial bow and the articulator assembly are particularly appropriate here. From this head, musculoaponeurotic postural chains start which ensure the stability of the standing man.

These channels were described by G. Struyf-Denys then taken over by B. Darraillans and M. Clauzade in 1989.

There are 5 postural musculo-aponeurotic chains:

3 anteroposterior phasic chains called lingual, facial and central which ensure the anteroposterior balance of the individual. The mandible acting as a regulator.
2 tonic-phasic side chains called masticators that provide a relational function of introversion or extraversion.

2. The cranio-mandibular relationship

It constitutes the musculoskeletal and neuronal reference system in which the dental occlusion comes into play. This is in agreement with the theses defended by the gnathologists, but also closer to us as R. Slavicek or Ph. Dupas.
It is necessary to distinguish the box and the teeth: it is necessary to give priority to the box before placing the teeth.

2.1 In the anteroposterior direction

The anteroposterior postural organization is subject to an orthopedic compensation law:

• any pathology or cranial anteroposterior dysmorphosis finds postural vertical compensation in the body.

• any postural vertical pathology in the body will find anteroposterior compensation in the skull.

The mandible thus plays the role of postural anteroposterior compensator, but also behavioral by regulating the anterior and posterior posterural chains, that is to say, lingual and facial.

The skeletal class I individual is an adaptive biotype with optimal verticality. It will be the model sought in our therapeutics.
Skeletal class II or III individuals are compensatory biotypes and have posterior or posterior compensatory postures.

However, the gravity, by the permanent vertical force which it exerts, may constitute a further decompensation factor during aging, in particular for Class II.

2.2 In the transverse direction

Curiously, the human system does not have a buffer system, a cross-compensation system.
Any dysmorphosis or transverse dysfunction will be pathological and will give a biotype of decompensation. Crossed joints or mandibular latero-deviations will necessarily induce postural asymmetry and must be systematically treated.

However, the lesion may appear asymptomatic in the oral cavity and can be exercised at a distance. It will then give rise to cervical pain, tendonitis or pubalgia.

In this transversal sense, we need to include emotional or relational aetiologies which are considered as transversal pathologies and which can then constitute systemic co-factors and thus tip a compensated system into a decompensated system.

In this systemic concept of pathology, malocclusion must be considered as a necessary but not sufficient condition. The state of the system, its historicity then provides the dynamics to the pathology.

Thus, two opposite dynamics can be conceived for the same class II / 2 system:

an asymptomatic functioning in an individual who presents a rich and rewarding social, affective and professional life.
dysfunction in an individual who has multiple emotional, emotional or social problems.

3. The temporomandibular joint

The temporomandibular joint (TMJ) is a fundamentally compensatory region between the two great postural systems that we will discuss later: the craniosacral system and the cranio-mandibular system. This region must be endowed with a special nature and properties that enable it to assume this role.

A joint plays only a role of sliding or transmission, there is no idea of remodeling or compensation. When she exceeds her adaptive capacities - either by trauma or by excess - she breaks or tears.

This very particular specification made us qualify the temporomandibular joint "suture" in agreement with the work of PH CAIX (17), G COULY (18-19), and J DELAIRE (20). It is a specialized cranial suture whose nature is confirmed by several facts:

histologically, a suture is the joint formed between two mesenchymal bones. Squamosal temporal and dental are precisely mesenchymal nature.
cracks called "blastemas" appear at the 8th week of intrauterine life in the connective tissue between these two bones and give rise to the meniscal system. It is therefore a given entity and not a unitary process as for a classical articulation.
at birth, the glenoid cavity is flat. It will take its adult convex form under the action of chewing. It is therefore the function that modulates the form, a role devolved to a suture.
between birth and age 6, TMJs undergo positional drift and move from an exo-temporal position to a sub-basi-temporal position
the presence of a particular cartilage, called "fibrocartilage", at the level of the glenoid cavity and the condyle endowed with healing and remodeling properties.
This sutural state gives the mandible a permanent compensatory role and reinforces us in the orthopedic role that we attribute to it. It formally contra-indicates any surgical action that would result in turning this sutural tissue into fibrotic tissue capable of creating post-therapeutic ankylosis.

4. The trigeminal

The dental surgeon does not work on teeth, but on the trigeminal.

In this, he has an action that is closer to the neurologist than to the mechanic prosthetist to whom he is confined. The nature of the occlusion is essentially neurological and trigeminal.
Le trijumeau est le nerf du 1er arc branchial qui donnera naissance à la face. Ainsi, le trijumeau constitue l’axe neuro-matriciel de la face.

4.1 The trigeminal and the hard-mothers

The trigeminal is often apprehended especially in our profession only in its extra-cranial portion and its terminal branches V1, V2 and V3.

However, these different branches present, before or after their cranial exit, meningeal branches which have been described by LAZORTHES.
This trigeminal innervation of the dura mater (the tissue element which forms the meninx) is crucial to consider in the physiology of the balance of cranial function.

These hard-mothers are called "reciprocal tension membranes" by osteopaths, because they will manage the cranial tension balance in the antero-posterior plane, but also in the transverse plane.

It is through these meninges that the cerebrospinal fluid flows from the villi of the third ventricle. The fluctuation of the cerebrospinal fluid is the basis of the dynamics of the craniosacral system of osteopaths.

4.2 The trigeminal nerve: global nerve

4.3 The trigeminal and reticular formation

Control of the vital functions of the heart, lungs and intestines, as well as of wakefulness and sleep, takes place at the level of the brain stem in a region called the "reticular formation", which is a neuronal associative region with specific functionality and a network of connections (30).

Monoamine nuclei such as the locus coeruleus and acetylcholine are essential for memory and attention. They also play an essential role in the regulation of sleep and wake cycles.

We reported that the motor nucleus of the trigeminal nucleus was confused with the locus coeruleus (nucleus monoamine to norepinephrine or norepinephrine) and we had already shown the close relationship between the trigeminal and the reticular formation (31-32-13-2).
The close relationship between the trigeminal and the locus coeruleus supports us in several assertions:

- the mandible is a noradrenergic system ;
- the morning or late night symptomatology found in our occlusal lesion pattern;
- the frequency of insomnia, headaches and migraines in our patients suffering from temporo-mandibular dysfunctions.

The proximity of the different nuclei of the reticulum and the trigeminal nuclei suggests interreactions and perhaps also "buggs" at the origin of the varied symptomatology that can be encountered in these dysfunctions, which can range from a change in taste to a change in the person's mood.

Let's not forget that the mouth is the organ that has evolved the most during phylogenesis. B. CYRULNICK speaks of the "bewitched mouth" because it has gone from a function of grip-defence to a function of verbalization-speech (33).

In the light of all this work, isn't the trigeminal one of the main vectors for the emergence of consciousness?
Located in the archaic brain, the trigeminal also participates fully in the construction of the proto-self, which is the first unconscious Self (30).

The oral cavity and orality are the building blocks of every individual; foundations on which the cognitive structure will be built.

We better understand the distress of our patients in the context of cranio-mandibular dysfunctions which necessarily present a structural mechanical side, but also an emotional and psychological side. Their treatment can be very complex and require multidisciplinary teams including psychologists and psychiatrists.

Front view of the trigeminal for dental treatment :