Studio Dentistico - Dr. Raffaele Schiavoni

Il Trattamento Ortodontico nei Pazienti Disfunzionali
Metodica “Occlusal Reading Splintless”
La ricostruzione globale dell’occlusione
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Tale metodica si basa sul trattamento ortodontico senza "preterapia" (uso di Splint Interocclusali), mediante apparecchiature fisse (tecnica MBT - tecnica di Damon).
Ogni malocclusione, infatti, può essere considerata la risultante della alterazione del pattern eruttivo fisiologico indotta da cause endogene o esogene. Anche nei casi più compromessi è possibile, "leggendo" l’occlusione, individuare il percorso compiuto dal sistema stomatognatico nel suo insieme nel determinare la situazione in esame. Ripercorrere a ritroso tale percorso, non guidati da norme astratte ma dall’osservazione clinica e dei dati strumentali, costituisce la forma più corretta di ricostruzione globale dell’occlusione.

An “occlusion guided” approach to the treatment of TMD patients
Splintless treatment of TMD patients
Raffaele Schiavoni
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The importance of occlusion as an etiologic factor in signs an symptoms of temporo-mandibular disorders (TMD) has been a source of controversy.
A number of studies on the etiological role of occlusion in TMD concluded that there is no scientific evidence of a causal relationship. Clinicians are reminded of this and of the ensuing need of understand these disorders in a biopsychosocial framework, by avoiding mechanistic thinking and treatments.
On the other hand, in the daily practice, many clinicians are dealing with treatments of patients suffering from TMD, showing a complex of obsessively repetitive occlusal aspects.
To accept the fact that there is no special orthodontic viewpoint required for dealing with TMD patients can lead to therapeutic paralysis or to persist with the so called “reversible therapy” indefinitely. But how can an endless therapy be defined “reversible”?
Occlusion continues to remain an enigma. It is difficult to establish any significant cause-effect relationship because of the number of variables involved in this multifactorial pathology. Many of these variables are difficult, if not impossible, to exclude from a clinical point of view.
A static evaluation of the occlusal condition fails to reveal any significant associations. Only by accessing the dynamic relationships of the occlusion during function can the true impact of the occlusion be appreciated.
When the occlusal condition affects the orthopaedic stability of the mandible, as it loads against the cranium, there are valid reasons for occlusal treatment.
The clinician is advised to proceed cautiously, using the least invasive procedures. The goal is to reconstruct the occlusion that has been damaged to its original features following the guidelines dictated by the examination of the occlusion itself.
When posterior vertical dimension is collapsed the main role in the skeletal arch of closure of the mandible is played by the axial inclination of the front teeth. This means that if posterior teeth don’t stop the closure of the mandible, it becomes the responsibility of the anterior teeth. If the anterior teeth have to stop the mandible’s closure, the result will be labial movement of the upper front teeth or posterior displacement of the lower jaw. This depends from many variables: the axial inclination of the lower and upper incisors; chewing pattern; skeletal pattern; parafunctional activities.
If the upper incisors are vertically or relatively vertically positioned a posterior shift of the lower jaw is likely to occur. This can leads to a non functional position of the condyle-disc assembly in the fossa. The real problem is: what does mean “collapse of the posterior vertical dimension”?
When teeth have been lost and a deep bite is present is not difficult to visualize this non-coordination “ reading ” the occlusion. In other cases this kind of deficiency is not easily detectible and not quantifiable by any kind of instrumentation. In the natural dentitions the lower teeth receive a force to their distal inclines which in time would result in mesial movement of the lower teeth and subsequent crowding of the lower anterior teeth; the more the teeth are on forceful contact as in period of bruxing, the faster the mesial movement. Any mesial movement of posterior teeth means per se a collapse of posterior vertical dimension.
Only careful observation of the occlusion during function, together with the information brought by the patient’s history and feelings, can show what happened during years. Often the etiologic diagnosis is in the history if we choose to listen and to see. Unfortunately sometimes we are deaf and blind.
The non-coordination between posterior vertical dimension and the anterior guidance not always cause the temporo-mandibular disfunction. An emotional stress or something occurs that leads to pathology.
The comprehension of this phenomenon is the most important time in the diagnosis of the pathogenesis of TMD. Not in all cases a repositioning of the lower jaw is needed. In most cases only a reconstruction of the occlusion per se allows to a counterclockwise rotation of the mandible with a posterior lowering of the condyle that permits a more functionally oriented position of the disc-condyle assembly.
Also if the occlusion is heavily damaged is possible, on the basis of clinical normal parameters, to improve the musculoskeletally determined position of the mandible.