Post-Isometric Relaxation in Temporomandibular Disorders (PIR-TMD)

Sanem ŞENER

Status: Not yet enrolling

Conditions: Myofascial Pain Syndromes; Temporomandibular Joint Disorders; Mandibular Dysfunction

Treatments: Behavioral: Postural Exercises + Post-Isometric Relaxation (PIR) Technique; Behavioral: Postural Exercises

Study type: Interventional

Funder types: Other

Identifiers

NCT07130279

TME-PIR-2024-01

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 40 estimated patients

Sex: All

Ages: 18 to 25 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age between 18 and 25 years
• Diagnosis of moderate or severe temporomandibular joint dysfunction (TMD) according to the Fonseca Anamnestic Questionnaire
• Presence of TMD symptoms for at least 6 months
• No TMD treatment received within the last 6 months
• Presence of chewing muscle pain for at least 6 months
• Able and willing to participate in the study and follow the exercise program
• Signed informed consent form

Exclusion criteria

• History of jaw or facial trauma within the past year
• History of temporomandibular joint surgery
• Presence of systemic rheumatologic, neurological, or musculoskeletal disorders affecting the jaw, neck, or spine
• Pregnancy
• Current participation in another clinical trial
• Inability to perform the exercise program due to medical or physical limitations
• Refusal to provide informed consent

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

---

40 participants in 2 patient groups

Experimental Arm: Postural Exercises + Post-Isometric Relaxation (PIR) Technique

Experimental group

Description:

Participants in this group will perform a standardized postural exercise program targeting cervical and thoracic regions, three times per week for six weeks. In addition, the Post-Isometric Relaxation (PIR) technique will be applied to the jaw muscles during each session, following a standardized manual therapy protocol to reduce muscle tension and improve mandibular mobility.

Treatment:

Behavioral: Postural Exercises

Behavioral: Postural Exercises + Post-Isometric Relaxation (PIR) Technique

Control Arm: Postural Exercises Only

Active Comparator group

Description:

Participants in this group will perform the same standardized postural exercise program targeting cervical and thoracic regions, three times per week for six weeks, without the addition of the PIR technique.

Treatment:

Behavioral: Postural Exercises