Journal of Craniomandibular Function, 02/2009

Background: Arthritis is an inflammatory disorder that is often associated with the loss of structure and function of the joints such as the temporomandibular joint. Motion-based therapies and mechanical loading of joints are a promising therapeutic approach in arthritis. Objective: This review is dedicated to the question how the clinically positive effects of mechanical joint loading and motion-based therapy, respectively, are accomplished at cellular and molecular levels. Summary: In various studies it has been shown that synthesis of proinflammatory mediators, matrix-degrading enzymes, and mediators of bone resorption can be inhibited by applying dynamic tensile strain to articular cells. These joint-protective effects are dependent on duration, amplitude, and frequency of strain. However, static tensile strain applied to joint cells seems to inhibit the synthesis of reparative molecules. Conclusion: Numerous in-vitro, animal, and clinical studies emphasize the great potential that a controlled clinical application of biomechanical loading may have for prevention and therapy of inflammatory temporomandibular joint disorders. Keywords: temporomandibular joint, arthritis, motion-based therapy, mechanical loading, tensile strain

The SensoBite System is a novel measuring system for bruxing events that can be integrated into occlusal splints. It is a diagnostic tool that enables clinicians to measure the actual wear time of the splint as the basis to monitor and enhance patient compliance. It also offers the opportunity to correlate bruxing events with a time of day or with particular circumstances. Furthermore, it allows better assessment of the effectiveness of further interventions (eg physiotherapy). The measuring system is currently being investigated in a preclinical and clinical setting. As a first step, the reliability of the measuring system was demonstrated with the help of a laboratory test. A study with human subjects was conducted to verify the validity of the measuring and transmission system, in which the subjects had to carry out different loading tasks following a measuring protocol. The test results showed that the individual events could be distinguished clearly in the data and also showed the pertinent force distribution over time. Currently, a comparative clinical study is being conducted to compare the results of the SensoBite System with those of electromyograms as the gold standard. The first set of results show a high degree of consistence of the two measuring modalities. Keywords: occlusal splint, splint, validity, reliability, compliance, SensoBite, bruxism, craniomandibular dysfunction

The present study examines the influence of occlusal interference on the stereographically determined functional status of the back. Examinations took place in 15 healthy volunteers (all female) in whom "artificial" occlusal interference was imposed with tin foils and its influence on the spinal system measured with the Formetric system. Rasterstereography failed to demonstrate a significant or even appreciable effect due to intervention. Presently, the suitability of rasterstereographic examination for the evaluation of occlusal influences on craniomandibular or craniovertebral pain syndromes cannot be confirmed. Keywords: craniomandibular dysfunction, diagnostics, occlusion, posture, spine

Interactions between posture and functioning of the craniomandibular system are well documented in research studies and case studies. For dentists who engage in functional diagnostics and treatment procedures, knowing these correlations is often a prerequisite for understanding the etiology and pathogenesis of craniomandibular dysfunction or disorder. Observing these correlations also helps prosthodontists to avoid problems related to the occlusal design and integration of dental restorations. A majority of the lawsuits on record following dental treatment concern reconstruction of the jaw relations or of occlusal surfaces. This article discusses the basic mechanisms of interaction between the static load acting on the body and the function of the spine and the jaw relations. Correlations are explained in such a way that they can be easily comprehended by dentists for whom judging someone's body posture is not part of their daily routine. The article focuses on malpositions leading to biomechanical stresses through a static load on the sagittal, frontal and transverse planes as well as on dysfunctions of the cervical spine and other spinal segments - particularly in the region of the sacroiliac joint - and their reciprocal effects with the craniomandibular system. Keywords: malposition, dysfunction, vertebral column, cervical spine, sacroiliac joint, craniomandibular dysfunction