FDI Worldental Daily, 15 September

www.fdiworldental.org ANNUAL WORLD DENTAL CONGRESS NEWSPAPERYOUR FDI WDD #2, September 15, 2011 26 tain TMJ disorders, however rarely appears to betheonlyone.Asgenerallyknown,thereare patients who, despite extreme malocclusion, show hardly any, or no TMJ discomfort, while other patients are sometimes severely affec- ted despite minor occlusal discrepancies. Craniomandibular disorders (TMD) result from an interplay of multiple factors: • malocclusion, overloading of the tempo- romandibular joint (compression, forced position) • hyperactivity of masticatory muscles (bruxism/clenching) • psychosomatic disorders, stress syndrome • joint hypermobility, particularly in com- bination with general connective tissue weakness (Fig. 2, 2a). • trauma • neck disorders / cervical spine syndrome • internal diseases (hormonal, circulatory disorders, rheumatism) TMJ internal derangement results from joint hypermobility rather than from malocclusion. In a 12-year long-term study (1997-2009), by our orthodontic practices, all patients with diagnosed disc displacement (n = 535) were manually examined for their bite position, including the wrist joint. In cases of doubt, magnetic resonance images were obtained. Anterior disc displacement, with reduction, wasfoundin421patients,while114patients showed displacement without reduction. The association with connective tissue weak- ness was highly significant. Concomitant ge- neral connective tissue weakness was obser- ved in 92.5 per cent of the patients (Fig.2b). In contrast, no significant association was re- vealed between malocclusion and the above- mentioned disc disorders. Therefore, some doubts are raised about the indication of disc repositioning with occlusal rehabilitation. This type of therapy is often complicated, time-consuming and expensi- ve,andnotwithoutriskinthecaseofsurgical repositioning. Moreover, this therapy does not necessarily protect from complete disc displacement, without reduction, at a later stage. Even when therapy achieved optimum occlu- sal conditions and complied within narrow limits of indication, there were usually intact posterior ligaments. This is true in partial an- terior disc displacement, and the presence of a distal bite in need of treatment. According to our current AquaSplint concept, clicking alone does not constitute an urgent need for therapy. On the other hand, existing pain symptoms have to be examined as to whether they actually originate from the tem- poromandibular joint/masticatory muscles. Phantom or referred pain has to be excluded by tissue-specific manual diagnostics. The next diagnostic step should aim to determi- ne whether malocclusion is the main cause of pain. This is achieved most effectively through (temporary) neutralization / disen- gagement of the existing malocclusion using theAquaSplint.Thus,apossibleforcedbiteis eliminated and the muscles become relaxed. In more serious cases, manual and physical adjunct therapy should be applied. A malocclusion-related TMD will usually res- pond due to AquaSplint therapy within four weeks. Pain relief of at least 50 per cent is a favourable precondition and indicator of promising orthodontic rehabilitation. Use of the AquaSplint often changes the bite. Subsequently, the resulting new and almost painless bite position may require orthodon- tic rehabilitation, or at least stabilization, by means of an adjusted splint for night time use. •Hiperactividadarticular,sobretodoencombi- nacióncondebilidadgeneraldeltejidoconjunti- vo(Figs.2y2a) •Trauma •Trastornosdelcuello/síndromedelacolumna cervical • Enfermedades internas (trastornos hormona- les,circulatorios,reumatismo). En la ATM los trastornos internos son provoca- dos por la hiperlaxitud articular, no por la malo- clusión.Enunestudiode12años(1997-2009), largoplazoennuestrasprácticasdeortodoncia, todos los pacientes con desplazamiento discal diagnosticado (n=535) fueron examinados manualmente para determinar su posición de mordida, incluyendo la articulación. En caso de duda, se recurrió a exámenes con imágenes de resonancia magnética. Se observó desplaza- mientodeldiscoanterior,conreducción,en421 pacientes, mientras que en 114 pacientes se observódesplazamientosinreducción. La débil asociación con el tejido conectivo fue muy significativa. Una debilidad general con- comitante del tejido conectivo se observó en el 92,5%delospacientes(Fig.2b).Encambio,no seobeservóunaasociaciónsignificativaentrela maloclusión y los trastornos del disco mencio- nados. Por lo tanto, existen dudas sobre la indicación de reposicionar el disco durante la rehabilita- ción oclusal. Este tipo de terapia es a menudo complicada, lenta y costosa, y no sin riesgo si es necesario el reposicionamiento. Además, no protege contra el desplazamiento del disco, sin reducción,enunaetapaposterior. Incluso cuando obtiene condiciones oclusales óptimas y respeta los estrechos límites indica- dos, se oberva que los ligamentos posteriores generalmente permanecen intactos. Esto es cierto en el desplazamiento parcial del disco anterior y cuando la mordida distal debe corre- girse. Figura 7. El exceso de silicona pueden eli- minarse a los 2 ó 3 minutos. Figure7.Excesssiliconcanberemovedin 2 to 3 minutes. Figura 8. Para su uso permanente es necesario agregar una delgada capa de material estabilizador. Figure 8. For permanent use you need to add a thin layer of stabilizing material. Figura 9. Figure 9.