Post-Isometric Relaxation in Temporomandibular Disorders

Overview

This planned randomized, single-blind clinical trial will investigate the effects of adding the Post-Isometric Relaxation (PIR) technique to a standard postural exercise program in individuals with moderate to severe temporomandibular joint dysfunction (TMD). Forty volunteers aged 18-25 years will be recruited and randomly assigned to either an experimental group (postural exercises + PIR) or a control group (postural exercises only). The intervention will be delivered three times per week for six weeks. Primary outcomes will include cervical range of motion, mandibular mobility, head anterior tilt, and thoracic kyphosis index, measured before and after the intervention. The study aims to determine whether PIR provides additional benefits to standard postural exercises in improving jaw and neck function and postural alignment in young adults with TMD.

Temporomandibular joint dysfunction (TMD) is a common musculoskeletal condition characterized by jaw pain, limited mouth opening, and joint sounds, often accompanied by postural deviations such as forward head posture and thoracic kyphosis. Conservative treatments, including postural exercises and manual therapy, are recommended to improve jaw and neck function and reduce symptoms. The Post-Isometric Relaxation (PIR) technique is a manual therapy method that uses gentle isometric contractions followed by passive stretching to reduce muscle tension and increase mobility. While PIR has been shown to improve masticatory muscle function, its combined use with postural exercises in TMD management has not been fully evaluated. In this planned study, forty volunteers aged 18-25 years with moderate or severe TMD (diagnosed using the Fonseca Anamnestic Questionnaire) will be recruited. Participants will be randomly assigned into two groups: Experimental group: Postural exercise program + PIR technique Control group: Postural exercise program only The postural exercise program will include strengthening, stretching, and mobility exercises for the cervical and thoracic regions, performed three times per week for six weeks. In the experimental group, the PIR technique will be applied to jaw muscles according to a standardized protocol. Outcome measures will include: Cervical range of motion (flexion, extension, lateral flexion, rotation) measured with a goniometer Mandibular mobility (depression, lateral deviation, protrusion) measured with a caliper Head anterior tilt (chin-sternum distance, occiput-wall distance) Thoracic kyphosis index measured with a flexicurve Assessments will be conducted before the intervention and after the six-week program. The primary hypothesis is that the addition of PIR to postural exercises will produce greater improvements in cervical and mandibular mobility than postural exercises alone. This trial is expected to provide new evidence for combining manual therapy with exercise in the management of TMD in young adults and may help guide future rehabilitation strategies.