A stepwise multiple regression model to assess the odds ratio between myofascial pain and 13 occlusal features in 238 Italian women.

OBJECTIVE: To quantify the relative risk of multiple occlusal variables for muscular disorders of the stomatognathic system. METHOD AND MATERIALS: Thirteen occlusal features were clinically assessed by the same three operators: partial unilateral posterior reverse articulation, anterior open occlusal relationship, vertical anterior overlap (normal value < 4 mm), complete unilateral posterior reverse articulation, anterior overjet (normal value < 5 mm), incisor midline discrepancy (normal value < 2 mm), Angle Class I canine and molar relationship; plus dynamic occlusion features such as length and symmetry of retruded contact position-intercanine position (RCP/ICP) slides (normal value < 2 mm), occlusal guidance patterns, and mediotrusive and laterotrusive interferences. The sample consisted of 156 women with only muscular disorders according to the Group I Research Diagnostic Criteria for temporomandibular disorders and 82 healthy women (control group). A stepwise multiple logistic regression model was used to identify the significant correlation between occlusal features and disease. RESULTS: The odds ratio for myofascial pain was 2.6 for absence of canine guidance, 2.0 for laterotrusive interference, 2.3 for mediotrusive interference, and 1.9 for reverse articulation. Other occlusal variables did not reveal statistical significance. The percentage of the total log likelihood for myofascial pain explained by the significant occlusal factors was acceptable with a Nagelkerke R2 = 0.2. The final model including the significative occlusal features revealed an optimal discriminant capacity to predict patients with myofascial pain with a sensitivity of 62.2%, or healthy subjects with a specificity of 93.6%, and an accuracy of 82.8%. CONCLUSIONS: Few occlusal features show a significative predictive value for myofascial pain.

Current concepts on the functional somatic syndromes and temporomandibular disorders.

BACKGROUND: The importance of psychosocial factors in the etiopathogenesis of temporomandibular disorders (TMD) has led to the hypothesis that these disorders may be part of a wider group of somatoform disorders, the functional somatic syndromes (FSS). Types of studies reviewed. The present paper is an overview summarizing the current concepts on the TMD-FSS relationship. A non-systematic search in the Medline database identified peer-reviewed papers on the epidemiological and clinical characteristics of the complex groups of disorders labelled functional somatic syndromes, focusing on the common features to temporomandibular disorders patients. RESULTS: Literature data suggest that FSS and TMD share many etiopathogenetic and epidemiological features, both groups of disorders having a multifactorial etiopathogenesis and needing a multidisciplinary approach to diagnosis and treatment. Psychosocial characteristics of patients seem to have many similarities and the prevalence of Axis I psychiatric disorders is elevated. The majority of studies focused on the relationship between TMD and fibromyalgia (FM), due to the high rate of orofacial involvement related to FM. Clinical implications. The presence of common features between TMD and FSS patient may suggest the need for changes in the diagnostic and therapeutic approach to TMD patients, with the introduction of treatment protocols which also address the psychosocial impairment accompanying TMD symptoms, in order to overcome the limits of traditional therapies.