Efficacy of Physiotherapy in Patients With Temporomandibular Disorders.

Pain intensity scale. This scale consists of a horizontal line of 100 mm, delimited at one end by 0 mm (no pain) and at the other end by 100 mm (worst pain imaginable). This scale has shown a high validity and reliability for the assessment of the pain intensity of the patient

Helkimo Index. This index is based on the evaluation of five clinical signs: 1. Alteration of the range of movement by measuring the amplitude of the movements of the jaw: opening, lateralisation and protrusion of the jaw; 2. Alteration of the TMJ function (appearance of sounds in the joint during the vertical opening of the mouth, and mandibular trajectory pattern); 3. Muscle pain; 4. Pain upon palpation of the TMJ; 5. Pain during the movement of the jaw38. Each item evaluated is scored with values of 0, 1 or 5, with the sum of the scores of the clinical signs evaluated, the one referring to describing the severity and the group for each patient with TMD41. If the score obtained is 0, patients are included in group 0 (absence of symptoms). Scores from 1 to 4, group 1 (mild dysfunction). Scores from 5 to 9, group 2 (moderate dysfunction). And finally, if the score is from 10 to 25, the patients belong to group 3 (severe dysfunction).

Quality of life questionnaire. The SF-36v2 is composed of 36 items with Likert type response options, which are included in 8 dimensions: Physical Function (FF, 10 items), Physical Role (RF, 4 items), Body Pain (DC, 2 items) , General Health (SG, 6 items), Vitality (VT, 4 items), Social Function (FS, 2 items), Emotional Role (SR, 3 items) and Mental Health (SM, 5 items). The scores range from 0 to 100 in each dimension, with the highest scores associated with a better state of health. This questionnaire has demonstrated a high internal consistency with a Cronbach's alpha value of more than 0.70, and an adequate reliability (ICC = 0.73-0'86).

Cervical disability questionnaire (NDI). It is a self-completed questionnaire formed by 10 sections: cervical pain intensity, personal care, weight lifting, reading, headache, concentration ability, work capacity, driving, sleep and leisure activities. The scores for each section range from 0 to 5, being 0 (without disability) and 5 (total disability). If a score ranges from 0 to 4, the patient would not have cervical disability. Scores from 5 to 14 (mild disability), from 15 to 24 (moderate disability), from 25 to 34 (severe disability) and from 35 to 50 (complete disability). Therefore, the maximum score that can be reached in this questionnaire is 509.45. The test-retest reliability has been shown to be optimal with an intraclass correlation coefficient of 0.978, and a high internal consistency with a Cronbach's alpha coefficient of 0.937.

Vernier caliper. To measure the active opening of the mouth without pain a vernier caliper will be used (Vernier Caliper). To do this, patients remain in a sitting position and are asked to perform a maximum opening of the mouth without pain. The distance between the upper and lower central incisors of the mandible is measured, using the millimeters as the unit of measurement. 3 consecutive measurements are made with rest intervals of 30 seconds. The final measurement is obtained based on the average of the 3 results belonging to the previous measurements. This procedure has shown high intra-rater reliability (ICC = 0'9-0'98).

Algometer. To assess the pain threshold at the pressure of the masseter, temporal and ECOM muscles, a mechanical pressure algometer (Wagner Instruments FDK 20) will be used. The pressure pain threshold is the minimum pressure that is needed to cause pain or discomfort at a certain point. In obtaining the result, the average of the 3 scores obtained from each point was made. The reliability of this procedure is high in healthy subjects [BCI = 0.91 (95% confidence interval: 0.82-0.97)] 28.31. In patients with TMD, reliability is moderate (ICC = 0.64)

Goniometer. The range of joint movement of the neck is measured by the use of a goniometer. Flexion, extension, lateral tilt and cervical rotation are assessed. To be able to perform the measurement, the patient is asked to remain in a sitting position keeping his back at 90 degrees and his head in a neutral position. The physiotherapist instructs the patients to perform the previously explained movements, until reaching the maximum range of movement or in the presence of pain. We proceed to evaluate mobility in the 3 planes: sagittal plane, frontal plane and transverse plane. 3 measurements of each movement are made, and the final measurement obtained is the average of each previous result.