Effect of Osteopathic Technique on Maximum Mouth Opening Width, Masseter Muscle Tone and Stiffness

Effect of Temporomandibular Joint Compression and Decompression Technique on Maximum Mouth Opening Width, Masseter Muscle Tone and Stiffness: A Randomized Controlled Study

The purpose of this study is to assess the effect of compression and decompression thecnique on the temporomandibular joint on maximum mouth opening width, masseter muscle tone and stiffness in asymptomatic adults, compared with a control condition consisting of cranial listening touch without therapeutic intent. Evaluations will be conducted immediately after the intervention and one week later.

The purpose of this study is to assess the Effect of Compression and Decompression Technique on the Temporomandibular Joint on masseter muscle tone and stiffness (always assessed on the right side). Muscle properties will be evaluated using the Myoton device (Myoton AS, Tallinn, Estonia), a non-invasive instrument that measures biomechanical and viscoelastic properties of muscles, such as stiffness and tone (the parameters used in the results).

In addition, maximum mouth-opening width will be assessed by measuring the distance between the upper and lower central incisors using a universal caliper, recorded in millimeters.

These outcomes will be compared with a control condition consisting of cranial listening touch without therapeutic intent .

The study will include asymptomatic adults without diagnoses of systemic inflammatory diseases, cardiovascular diseases, respiratory diseases , central nervous system disorders, or rheumatic pathologies. Additional exclusion criteria include: use of fixed orthodontic appliances within the past 3 months; visual impairment affecting balance or proprioception; history of maxillofacial surgery; trauma to the cranial or cervical region within the last 6 months ; ongoing pharmacological treatments that may interfere with muscle tone or pain perception (e.g., muscle relaxants, tricyclic antidepressants, benzodiazepines) and third/fourth year osteopathy students.

Measurements of the tone/stiffness of the masseter muscle and maximum mouth opening width will conducted before, immediately after the intervention and one week later the study will be repeated in each participant.

Inclusion Criteria:

• Asymptomatic adults that signed the informed consent
• Functional dentition
• Preserved masticatory function

Exclusion Criteria:

• Diagnosis of inflammatory systemic disorders
• Diagnosis of cardiovascular disorders
• Diagnosis of respiratory disorders
• Diagnosis of central nervous system disorders
• Diagnosis of rheumatic disorders
• Visual disturbance affecting balance or proprioception