Dr Giorgio Mambelli-Surgeon/Dentist/Gnathologist Via Argentario, 24-Ravenna (Italy) telephone : +39 0544 37036

THE BAD OCCLUSION AS A POSSIBLE CAUSE FOR ORGANIC ANXIETY SYNDROME

(All that follows has been discussed about at the International Congress: "Emozioni, Patologie, Terapie in Psichiatria" which took place in Rome on: December 10 th - 11 th - 12 th 1992 and pubblished on "Volume comunicazioni" page 295 to 302.)

(N.B. : Even if apparently treats only a specific subject matter, the Information  also develops all the Malocclusale Mechanism from which all the symptomatologies derive and about which all the symptomatologies derive and about which we have already said above, following a guiding line that also the outsiders can understand)

Unfortunately, but purposely, the area regarding the treatment has only been dealt with very briefly, for the reason that it is result of individual interpretations of muscular reactions evaluate and elaborated by the expert.)

Or. tit. "La Malocclusione quale possibile causa di sindrome d'ansia organica" in: "Emozioni, Patologie, Terapie in Psichiatria", Volume Comunicazioni, Gaspare Vella, Alberto Siracusano (eds.), pp.295-300

It is commonly known that it exists a relationship between muscular tautness and anxiety (1), a relationship that, most of the times, could remain within the acceptability bounds if it weren't for the intervention of some particular conditions able to increase both the anxious state and the muscular tautness, factors which afterwards exalt each other.

The emotional stress, the convulsive modern life, the succeeding of conflicting situations, the psychological tiredness, are but some of the particular conditions which have a negative influence upon the anxious state.

As regards the anxious condition, apart from a well-known symptomatic constellation (apprehension, suspense, worry and hypervigilance, restiessness and so on...), it also produces widely documented alterations at the muscular system level as well as at the skeletal, neurovegetative, neuroendocrine and immune ones (1).

It is thus clear the reason why such a weight is attached to anxiety to try to give an explanation to the many alterations which afflict human existence.

About the "autonomic nervous system" (sympathetic as well as parasympathetic) which innervates the visceral organs and the vessels, while the efferent ducts are well-known, those afferent ones, on the contrary, are less known but it's undeniable, and the clinic reaffirm it, that all the attacks which strike the organism, whatever their origin maybe, are translated into stimuli for the autonomic nervous system itself, which is the first to be informed of every impulse that reaches the "nervous system".

Personally l believe that the division of the "nervous system" into "somatic" and "autonomic" should be considered just at a technical level, in order to make scholars understand one another on an anatomical differentiation; but l think a distinction doesn't really exist for everything is "nervous system" even if a part of it is delegated to carry on a particular task rather than others pertaining to another part of it; actually l believe that both the parts form an inseparable one and both act together to assure the well-being of the organism.

In the same way it must be considered the differentiation between "proprioceptivet information" and "conscicous information".

As a matter of fact, even if not all the proprioceptive information are unconscious (those bulpetal ones for example are conscious) (2), all of them arrive at the cerebellum and in here they also have a relation with the cerebral cortex actually getting the possibility to become conscious.

Whatever the kind of proprioception, the final result is always the same, that is the motor responses happen beyond the person control (3).

There is still to say that these information can have an inhibiting character as vell as an exciting one.

Often the motor response happens at the "gamma mononeuron" level, as a consequence of sensorial/sensitive information caught as proprioceptive stimuli (4).

"Gamma mononeurons" in fact act directly on the poles of the "neuromuscular spindles" stimulating the "alpha mononeurons" while leaving the person absolutely unaware of everything.

The subject complexity is therefore undeniable as it isn't negligible the importance of "Gnathology" concerning the anxious state as actor or effect.

"Gnathology", as everybody knows, studies the mandible motor activity and the fitting relationship between the antagonist teeth surfaces, everything ruled by the "neuromuscular function" which is nothing but an integration of sensitive-motor circuits that rule all the limbs motor activity and consequently those of the mandible too for when we deal with gnathologic problems, we must talk about "mandibte-limb".

The fitting between the antagonist teeth surfaces is called "occlusion".

It is a very short time event because as soon as the antagonist teeth touch each other, an opening reflex automaticcally occurs that (18), in order to protect the mastication organ, makes the dental arches separate acting on the mandible lowering muscles and stimulating them to contract while at the same time inhibiting those lifting ones, thus making the teeth get out of occlusion.

The "physiologically executed occlusion" implies an uniform and simultaneous contact both on the right and on the left sides, from premolar to molar (4).

But if such a physiological situation is prevented by a disturbing hindrance put among the dental arches elements, the obstacle presence will be immediately and directly perceivend by the mesencephalic part of the trigeminal nucleus because the tooth and it's periodont are extremely rich in trigeminal receptors(10-12-13).

Dental/periodontal information can become part af either the proprioceptive or the nociceptive sphere (10), depending on the captive receptor kind, but the all of them, independently from the trigeminal nucleus portion concerned, will act on the "occlusive position control system" (17) to apparently re-establish such an uniform and simultaneous contact to the right and the teft between the dental arches, as to simulate a retum to the occlusive physiology ; thus creating a situation able to deceive an inexperienced eye.

The "occlusive position control system" will act on the mastication muscles motor nucleus which, rightly stimulating their fibres and fibrils, will make the mandible move as required, causing a "bad occlusive" phenomenon.

This way as far as the obstacle sjde is concerned, the mandible will be swerved toward the bottom, the forwards and the inside while, because it is a single bone with two articulations which have to produce a certain working synchronism, the opposite side will be moved toward the upside, the backwards and the outside (4 - 6 - 7).

It is absolutely understandable that such a curvature will be the origin of other interference which will generate the premises for countless of other stimuli on the centres responsible for the occlusion control and for likewise unexpected mandibular displacements.

This anomalous situation will persist until all the "disturbances" will be renoved and this will involve a long and patient gnathologic treatment which will make use of occlusive reposition plates (bite planes) (9), which will have to be frequently counterbalanced by the Gnathologist.

To keep the mandible steady into the band occlusive forced position quoted above, the mastication muscles fibres and fibrils will incur a stress state with considerable consequent suffering (4).

In fact, as they can't retire since, because of the "deglutition reflex", the "reverberative" stimulus caused by the "interference" on the cerebral nuclei will always be present, those fibres will become saturated with acid catabolites because of the increased catabolism connected to the hypertone and because of the induced blood-stasis due to the mechanical obliteration of their inside vessels.

Inside the core of the mastication muscles concerned, there will quickly appear some extremely painful areas "trigger zones" which can be discovered through an adequate palpation and which will be used by the "Gnathologist" as guides for the correct occlusive replacement.

"Trigger zones" can be found, for the same reason, in different corporal areas and sometimes far from the mouth, since the muscle/skeletal equilibrium is such just if all the muscular fibres and fibrils are normotonic but, as soon as a small disharmony occurs, whatever the organism district may be, all the system suffers for it as wholly interested in compensation.

We have to specify that even if a subject is seemingly immune from any kind of symptomatology whose origin is occlusion, it isn't necessary true that this occlusion has to be a physiological one.

As a matter of fact, often "bad occluded" persons do not present evident troubles as they live within a counterbalanced condition (5) between their sensitivity and the pathological state so that the "bad occlusion" can be bearable and the balance assures them a satisfactory life.

It must be also remembered that many symptomatologies "idiopathically" ascribed to different branches of the Medical Science, have their causal origin in occlusive problems.

Anxiety and depression for example, often have their "essential" root into the "bad occlusion".

Actually all the dental/periodontal stimulation collected by the proprioceptors, as intercepting peripheral terminations of the trigeminal nerve, will be sent also to the "autonomic nervous system" whose characteristic is to exchange every received information with all its parts, wholly involving itself while every ganglion of it receives all the information regarding its own particular area.

Even if it isn't perfectly comprehensible through which way or process an information carried to the trigeminal nuclei can be translated into a stimulus for the "autonomic nervous system" it is possible to suppose that, starting from the encephalon, it concerns its closest, inter and extra-cranial parts.

Since the "superior cervical ganglion" represents the most important station of the "vegetative nervous system" and the closest to the encephalon (23), we can assume it is the most sensitised by those impulses arriving at the brain and that it serves as an impulse selector for all the nervous system autonomic components.

The "superior cervical ganglion" than, both for its topographical position and for the close relations it forms with the whole inter and extra cranial vegetative nervous system, certainly has a predominant influence upon the person neurovegetative responses.

Hence it is clear how a simple bad occlusive phenomenon can affect the whole organism, with unexpected reactive responses it unconsciously involves the whole "nervous system" stimulating on the one hand motor responses and neurovegetative ones on the other.

In the first case they will be brought into action the "gamma motor responses" which surpassing the protective dental/periodontal frame of the stomatognathic apparatus, will be expressed into the "lockage" and into the "bruxism" (5 - 7); white in the second case, because of the coming into action of the "vegetative nervous system", there will have negative influences upon the "neurotransmitters" which could become reasons for psychosomatic alterations so as to exacerbate the anxious state.

What the "bruxism" is it's easy to say: it appears as a protracted contact, under stress, joined by the "grinding" movement (7).

The "bruxing phenomenon" is particularly active during the "rem" phase of the sleep and it intensifies when dreams are nerve-wracking.

During such a movement, the "precontact", carefully avoided during waking hours, is mostly exalted but, as we have just said, it is completely recovered into the grinding typical parafunctional movements.

The Patient enters a moodiness state, which he himself doesn't understand but which bothers him making arise even worse situations than those which caused the "bruxism".

Anxiety in fact is one of those factors that stimulate the "gamma motor responses" (7 - 8 - 15) which, as we have already sald, are the "bruxism" and the "lockage'" raising causes.

For a Patient there is nothing worse than the feeling to be persecuted by an undecided disease which isn't easy to express and which makes the Physician believe he is in front of a "somatiser" (20).

Because all the therapeutic treatments undertook apart from a temporary relief haven't been completely successful, the suffering person, fearing a chronicisation of this state, becomes victim of an highly weakening psychogenic component (1).

That said, it is clearly understandable that it is a continuous chasing one another among "anxious state", "bad occlusion" and "bruxism" , vicious circle which is possible to be solved just through a cautious "gnathalogic treatment".

In consideration of the damages caused by the "disturbances" it is logic wondering what the first cause cauld be.

They are certainly very simple things considered up to these days as having no importance.

We can say that a wrongly executed filling, a crown or a bridge, a total dental prosthesis or a partial one, a dental pain, an altered corner relation between the mastication level and the condylar pathway which doesn't allow the mandible to slide under the grinder without meeting any obstacle, the extraction of a dental element which will cause the inclination of the contiguous teeth at the resection point so as to generate precontacts, all of these are but few of the most common causes of the problem.

Some scholars also suppose that this kind of symptomatologies can arise because of corporal bad positions which can act indirectly on the stomatognathic apparatus becoming as a consequence, the "primum movens" of the whole question 22).

Others support the hypothesis that some stimuli acting on the Deiters (11) "lateral vestibular nucleus" and coming from the vestibule and from the cerebellum, can negatively act on the postural attitudes in the same way negative cerebellar influences on the "red nucleus".

Everything would break out for the direct action of these nuclei on the dorsal muscles through the "direct" and the "crossed vestibule-spinal" tracts and the "crossed rubro-spinal" one.

Even if l do not completely agree with the hypothesis quoted above, l think it is very important to specify that, even if we want to support such principles, we have to remember that not every anxious Patient really presents this kind of alterations since, because such a big size of the population is depressed/anxious, it should be otherwise opportune wondering whether most of the world isn't constituted by vestibule and cerebellum damaged persons!

To explain my perplexity l'd like to call Your attention to the fact that during the resting hours and assuming the clinostatic position, such interference would come to a stop while as regard to those Patients, object of our observations, during the sleep time the problem even intensifies.

It isn't rare in fact finding Patients who suffer more when they wake up as they feel their painful symptomatologies deeper without understanding the reasons why this can occur contrarily to what happens during motion time when all their painful reactions tend to wear off or to disappear.

This is justified just by the fact that, because of deglutition, which happens also during sleep time, the "bad occlusive stimulus", reflerberative in a "feedback" way on the cerebral nuclei (5), is always present with a consequent increased muscular/tensive state.

At this point l want to sum schematically up to better explain howt "bad occlusion" and "anxiety" are between them complementary situations.

The "bad occlusion" interacts on the "occlusive position control system" which, to increase the organism resistance to the physical alterations and to correct the "bad occlusion", generates "hypertonic" and "hypotonic" states on the mastication muscles fibres and in farther corporal districts, "trigger zones", so as to produce pain and anxiety because, as the Patient doesn't know the pain source, he is inclined to impute it to more serious factors than the real ones (16 - 21).

Hypertone than, as far as the farther corporal districts are cancerned, together with the lowering of the pain threshold which makes these parts ache as well, causing the Patient to cognitively equalise his pains to a serious illness, as a cardiac illness for example, makes serious symptoms arise, as an infarct for example, of a reflex origin: it is the "somatisation" which causes the increase of anxiety (19).

Because of the hypertone there comes a growth of lactates and of pyruvates (acid catabolites) thus a new pain, unknown to the Patient and often to the Physician too comes into being and because of it a state of "chronic stress" and "anxiety" after-effects arise with defusition of the "GABA" system, inhibition of the "endogenous opiate systems" and of "serotonin", with a consequent deeper painful stimulus due to the lowering of the "pain threshold" and an "anxiety" after-effects, a process which will give rise to the "organic anxiety syndrome" (20).

This last than on the one hand generates the "reactive depressive condition" out of whose symptomatic constellation it's hard to derive the pathological "noxa", sometimes with a lowering of the "pain threshold" after-effects, especially concerning "depressions", when there is a reduced "serotoningenic function"; on the other hand it promotes the arising of a "psychogenic risk area" due to the anxiety generated by the underestimated, and for this reason unmanageable, bad occlusive problem and so: "psychosomatic ailments" as well as cutaneous, gastrointestinal, asthmatic ailments and so on... (19).

Anxiety and pain will be in their turn causes for the hypertone intensification (21).

It will become a spiral without end if the pathogenic "noxa", the "bad occlusion", is not recognised and removed.

To conclude l still want to remind that the rising of the hypotone into corporal districts far from the"noxa" point has been used since a long time by Physiatrists for the neurodamaged motor rehabilitation techniques, because by stimulating the tone and the pain, they obtain tonic and motor responses in farther zones, even in counterlateral ones: they are the "far trigger zones".

That said and concluding it is hoped that an effective co-operation among the "Gnathologist" and the other Medical Specialities will come into being for, as we have demonstrated, "Gnathology" is not a Medical branch apart but an integral part of the whole Medicine.

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