The study aims to demonstrate the efficacy of the sensorimotor approach developed by A. Piron (taught to the patient in three sessions) regarding three parameters related to TMD: facial pain, functional incapacities and hypertonia.

The subjects in the study are 18 to 77 years old and present the following conditions: a TMD disorder caused or aggravated by hypertonia and responsible for cervico-maxillo-facial pain and/or a functional incapacity in the last 30 days.

Inclusion Criteria:

• Male or female subjects aged 18 to 77 years old.

Subjects presenting the following 3 characteristics:

1. A TMD disorder (objectivized by the DC/TMD 2014);
2. Facial pain in the last 30 days (objectivized by the Graded Chronic Pain Scale version 2.0 (GCPS v2.0)) and/or functional incapacity (chewing, mobility, verbal and emotional communication) in the last 30 days (objectivized by the Jaw Functional Limitation Scale 20 (JFLS-20));
3. Hypertonia (objectivized by the Oral Behaviors Checklist (OBC) short version and the Explanatory Model Scale).

Subjects who agree to comply with the requirements of the study. Subjects who are of age (and know how to read and write) who have given their informed, explicit consent in advance to any procedure related to the trial, the study or the investigation conducted on human beings, with the objective of developing knowledge specific to the exercise of health care professions, as set out in Royal Decree No. 78 of 10 November 1967 on the practice of the health care professions (Act of 27 December 2005).

Subjects insured under social security.

Exclusion Criteria:

• Any subject presenting at least one of the following criteria may not be included:
• Significant medical problems involving the following conditions:

Severe or progressive pathology (psychiatric, neurological, cardiopulmonary, renal, hepatic, endocrinological, hematological, neoplastic, infectious, metabolic or allergic).

Any acute trauma of the temporomandibular joint (trauma within the last 72 hours).

Severe anxiety or severe depression, as defined by a score greater than or equal to 15 on the HAD.

• Pregnant women
• Criteria related to prior or concurrent treatments:

Treatment with antipsychotics, anxiolytics, soporifics or muscle relaxants started within the two months preceding the study.

Treatment with intraoral implants during the study or in the two months preceding the study.

- Criteria related to lifestyle: Excessive alcohol consumption (WHO definition: more than two glasses per day for a woman and more than three for a man).

Subjects undergoing withdrawal or taking a replacement substance.

- Criteria related to the subject: Subjects unlikely, in the investigator's view, to comply with the instructions in the protocol.

Subjects unlikely, on the basis of a score <2 to question "C" of the Explanatory Model Scale, to comply with the therapy.

Subjects who had participated in a clinical trial in the previous month or were participating at the time of selection.

Subjects without the linguistic or psychological capacity to understand and sign the informed consent form and complete the psychometric questionnaires and psychological tests.

Exclusion criteria after acceptance in the study:

In addition to becoming aware a posteriori of an error related to the inclusion or exclusion criteria defined above, the therapist may decide to remove a subject before completion of the study.

The motivations for early exit are as follows:

• Subject who no longer agrees to comply with the requirements of the study.
• Occurrence of a major life stressor (score greater than 40 on the Holmes and Rahe Stress Scale).
• Need to redirect the subject to a different treatment. Any early exit from the study, whether decided on by the subject, the therapist or both together, will be recorded on a specific document, indicating the date and the reasons for the early exit.