Difference between revisions of "Systèmes complexes"

Elle joue un rôle déterminant dans la régulation de la respiration, de la locomotion, de la posture, de l'équilibre, de l'excitation (y compris le contrôle intestinal, la vessie, la pression sanguine et le rythme cardiaque). Il est responsable de la régulation de nombreux réflexes, dont la déglutition, la toux et les vomissements.. The brainstem is controlled by higher Cerebral Centers from cortical and subcortical regions, including the Basal Ganglia Nuclei and Diencephal, as well as feedback loops from the cerebellum and spinal cordNeuromodulation can be achieved by the ‘classical’ mode of glutammatergic neurotransmitters and GABA (gamma-amino butyric acid) through a primary excitation and inhibition of the ‘anatomical network’, but can also be achieved through the use of transmitters acting on G-proteinsThese neuromodulators include the monoamine (serotonine, noradrenaline, and dopamine) acetylcholine, as also glutamate and GABAIn addition, not only do neuropeptides and purines act as neuromodulators: so do other chemical mediators too, like Growth Factors which might have similar actions.<ref>{{Cite book  

The neural network described above does not end with the only correlation between trigeminal somatosensory centres and other motor areas but also strays into the amigdaloidei processes through a correlation with the trigeminal brainstem areaThe amygdala becomes active from fear, playing an important role in the emotional response to life-threatening situationsWhen lab rats feel threatened, they respond by biting ferociouslyThe force of the bite is regulated by the motor nuclei of the trigeminal system and trigeminal brainstem Me5The Me5 transmits proprioceptive signals from the Masticatory muscles and parodontal ligaments to trigeminal nuclei and motorsCentral Amygdaloid Nucleus (ACe) projections send connections to the trigeminal motor nucleus and reticular premotor formation and directly to the Me5.

To confirm this, in a study conducted among mice, the neurons in the Central Amigdaloide nucleus (ACe) were marked after the injection of a retrograde tracer(Fast Blue), in the caudal nucleus of the Me5, indicating that the Amigdaloians send direct projections to the Me5, and suggest that the amygdala regulates the strength of the bite by modifying the neuronal activity in the Me5 through a neural facilitation.<ref>{{Cite book  

  }}</ref>  

Modifying occlusal ratios can alter oral somatosensory functions and the rehabilitative treatments of the Masticatory system should restore somatosensory functions. However, it is unclear why some patients fail to adapt to the masticatory restoration, and sensomotor disorders remain. At first, they would seem to be structural changes, not just functional onesThe primary motor cortex of the face is involved in the generation and control of facial gold movements and sensory inputs or altered motor functions, which can lead to neuroplastic changes in the M1 cortical area<ref>{{Cite book  

==Conclusive Considerations==

In conclusion, it is clear from the premise, that the Masticatory system should be considered not certainly as a system simply governed by mechanical laws, but as a "Complex System" of indeterministic type, where one can quantify the "Emerging Behavior" only after stimulating it and then analysing the response evokedFigure 2). The Neuronal System also dialogues with its own encrypted machine language (potential action and ionic currents) and, therefore, it is not possible to interpret the symptoms referred to by the patient through natural language.  

This concept deepens knowledge of the state of health of a system because it elicits an answer from inside the network — or, at least, from a large part of it — by allocating normal and/or abnormal components of the various nodes of the network. In scientific terms, it also introduces a new paradigm in the study of the Masticatory System: the "Neuro Gnathology Function", that we will meet in due course in the chapter ‘Extraordinary Science’.  

Currently, the interpretation of the Emergent Behavior of the Mastication system in dentistry is performed only by analysing the voluntary valley response, through electromyographic recordings ‘EMG interference pattern’, and radiographic and axographic tests (replicators of mandibular movements). These can only be considered descriptive tests.

 

The RDC/TMD protocol was designed and initialized to avoid the loss of ‘standardized diagnostic criteria’ and evaluate a diagnostic standardization of empirical data at disposition.  

This protocol was supported by the National Institute for Dental Research (NIDR) and conducted at the University of Washington and the Group Health Corporative of Puget Sound, Seattle, Washington. Samuel F. Dworkin, M. Von Korff, and L. LeResche were the main investigators<ref>{{Cite book  

  }}</ref>.  

To arrive at the formulation of the protocol of the ‘RDC’, a review of the literature of diagnostic methods in rehabilitative dentistry and TMDs, and subjected to validation and reproducibility, has been made. Taxonomic systems were taken into account by Farrar(1972)<ref>{{Cite book  

  }}</ref>, andcompared them by granting them to a set of assessment criteria.  

The evaluation criteria were split into two categories that involve methodological considerations and clinical considerations.

The end of the research came to the elimination, due to a lack of scientific and clinical validation, of a series of instrumental diagnostic methodologies like interferential electromyography (EMG Interference Pattern), Pantography, X-ray diagnostics, etc. These will be described in more detail in the next editions of Masticationpedia. This first target was, therefore, the scientific request of an "objective data"' and not generated by opinions, schools of thought or subjective evaluations of the phenomenon’. During the Workshop of the International Association for Dental Research (IADR) of 2008, preliminary results of the RDC/TMDs were presented in the endeavour to validate the project.  

The conclusion was that, to achieve a review and simultaneous validation of [RDC/TMD], it is essential that the tests should be able to make a differential diagnosis between TMD patients with pain and subjects without pain, and above all, discriminate against patients with TMD pain from patients with orofacial pain without TMD.<ref>{{Cite book  

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<This last article, reconsidering pain as an essential symptom for the clinical interpretation, puts all the neurophysiological phenomenology in the game, not just this.

To move more easily at ease in this medical branch, a different scientific-clinical approach is required, one that widens the horizons of competence in fields such as bioengineering and neurobiology.

It is, therefore, essential to focus attention on how to take trigeminal electrophysiological signals in response to a series of triggers evoked by an electrophysiological device, treating data and determining an organic-functional value of the trigeminal and masticatory systems as anticipated by Marom Bikson and coll. in their. «''[[:File:Electrical stimulation of cranial nerves in cognition and disease.pdf|<span lang="en" dir="ltr" class="mw-content-ltr">Electrical stimulation of cranial nerves in cognition and disease</span>]]''».

We should think of a system that unifies the mastication and neurophysiological functions by introducing a new term: "'''Neuro-Gnathological Functions'''"<br>which will be the object of a dedicated chapter.

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