Relationship between self-reported pain, pain threshold, pain catastrophization and quality of life in patients with TMD

BACKGROUND: The aim of this study was to verify if there is a relationship between self-reported pain, PPT (pressure pain threshold) of the masseter, temporal and sternocleidomastoid muscles, pain catastrophizing and quality of life in patients with TMD (temporomandibular disorder) of muscular origin. MATERIAL AND METHODS: Ninety-seven patients with muscular TMD (TMD group) and 97 asymptomatic (control group) were included in the study. The evaluation methods used were: 1) Self-reported pain was assessed using the Visual Analogue Scale (VAS) for questions 7, 8 and 9 of the RDC/TMD Axis I questionnaire; 2) The PPT assessment was performed using a digital algometer on the masseter, temporal, and sternocleidomastoid muscles (both sides); 3) Pain catastrophizing was assessed using the PCS (Pain Catastrophizing Scale); and 4) Oral health-related quality of life was assessed using the OHIP-14 (Oral Healthy Impact Profile-14). Data were submitted to Spearman correlation and logistic regression (p<0.05). RESULTS: There were significant positive correlations between self-reported pain (VAS-Q7, VAS-Q8 and VAS-Q9), pain catastrophizing (PCS-Helplessness, PCS-Magnification, PCS-Rumination and PCS-Total) and quality of life (OHIP-14) (p<0.05). There was a significant negative correlation of self-reported pain (VAS-Q8) with PPT of the temporal (left) and sternocleidomastoid (both sides) (p<0.05). The rumination and magnification domains increased the chance of high self-reported pain in all situations (VAS-Q7, VAS-Q8 and VAS-Q9) (p<0.05). The helplessness domain only increased the chance of high self-reported pain for VAS-Q8 (p<0.05). The presence of TMD of muscular origin, high self-reported pain (VAS-Q7) or pain catastrophizing increased the chance of a low quality of life in relation to the control group (p<0.05). In addition, the reduction in sternocleidomastoid PPT increased the chance of poor quality of life (p<0.05). Key words:Myofascial pain syndromes, pain catastrophizing, myalgia, quality of life, surveys and questionnaires, temporomandibular joint disorders.