Statement Of Problem. The controversy continues regarding the efficacy of several commercially available devices that are used as aids in the diagnosis of occlusal abnormalities. Purpose. This article reviews the reliability, validity, and utility of instruments that claim to detect occlusal interferences and abnormal vertical dimension of occlusion. Material And Methods. Data, opinions, and technical information from 37 published articles were reviewed. Evidence for method reliability, validity, and utility was assessed. Results. Although occlusal contact detection devices can document the occlusal contact patterns on teeth, the basic in vivo testing of their reproducibility and validity has not been performed. Moreover, while EMG and jaw tracking systems can indeed measure jaw muscle activation and jaw position, no cost-benefit analysis of these devices has yet been conducted. One manufacturer suggests that these instruments be used in conjunction with an electrical muscle stimulation device to find a new resting jaw position that is more open vertically. This new, more open position has been inappropriately labeled as evidence of vertical dimension of occlusion overclosure. Conclusion. None of the instruments reviewed can be said to be more than ancillary documentation devices and they have been inadequately tested for reliability and validity. Moreover, because scientifically acceptable disease definitions are not available for these 2 conditions, the issue of over-diagnosing becomes a substantial concern. (J Prosthet Dent 2000;83:83-9.)

Reliability, validity, and utility of various occlusal measurement methods and techniques

The kinesiometric and electromyographic findings from the evaluation of mandibular resting posture in 30 individuals with diverse vertical dentofacial morphology can be summarized as follows: 1. The RVD and TESP of the mandible are two distinctly different biologically dynamic neuromuscular entities. They differ with respect to their spatial position in that the RVD is 2.6 mm closer to centric occlusion than TESP. 2. The intrapersonal reproducibility of the RVD and TESP at various time intervals predictably demonstrated some biologic variability. 3. The occlusal neuromuscular mechanism apparently maintains a functional tone in the masticatory musculature at the RVD as a result of stimuli from the periodontal mechanoreceptors following tooth contact. 4. A physiologic range of neuromuscular adaptability exists within each diverse morphologic group. Adaptations are apparently mediated by the central nervous system and the musculoskeletal complex. 5. The interocclusal distance at the TESP is inversely related to the vertical dentofacial morphology. 6. Sophisticated computerized morphometrics in combination with the kinesiometric and electromyographic findings of this study demonstrate the dentoalveolar nature of VME and VMD and suggest that correction of these dentofacial deformities by various biologically compatible means will tend to normalize neuromuscular-skeletal relations.

Evaluation of mandibular rest position in subjects with diverse dentofacial morphology

Neuromuscular adaptation to surgical superior repositioning of the maxilla.

The slopes of the V/T curves of masticatory muscles were determined in patients with MPD syndrome, and the changes in the slopes were observed prior to and during electrical muscle stimulation and splint therapy. The slopes of the V/T curves in patients with MPD syndrome were significantly steeper than those of the healthy subjects. In patients with MPD the slopes were decreased by electrical muscle stimulation of moderate duration and by insertion of the splint. These findings suggest that the most simple procedure for the diagnosis of MPD syndrome is to compare the slopes in MPD patients with those of healthy subjects. The observation of the changes in slopes during electrical muscle stimulation and splint therapy permits a more quantitative diagnosis of MPD syndrome. It also permits a quantitative measurement of improvement of symptoms in patients with MPD syndrome.

Quantitative electromyographic diagnosis of myofascial pain-dysfunction syndrome.

This article presented data on 92 edentulous patients in the age group of 54 to 84 years. The data describe the changes in vertical dimension of rest observed under different clinical conditions associated with the treatment procedures for construction of complete dentures.

Swain Cw

Papers

Physiological aspects of masticatory muscle stimulation: the myomonitor.