Temporomandibular joint disorders (TMDs) are a major public health problem as they are one of the primary sources of chronic pain and impairment of chewing, swallowing, speech, and breathing function [1]. TMDs are not limited to the temporomandibular joints (TMJ) or masticatory muscles alone. Still, they are often associated with other symptoms affecting the head and neck region, such as headache, ear symptoms, and cervical spine dysfunction [1].~In recent years, there has been a significant development in the knowledge of the aetiology, diagnosis and treatment of TMDs. With the continuous search for better diagnostic and therapeutic methods, attention has begun to turn to the possibility of using non-invasive therapeutic strategies in patients with TMDs symptoms. In particular, the collaboration between dentist and physiotherapist helps in early diagnosis and improves the effectiveness of therapeutic interventions [2].~The limited number of randomised controlled trials (RCTs) comparing the efficacy of soft tissue manual therapy and self-therapy interventions prompted the researchers to focus on the analgesic and myorelaxant use of massage, post-isometric muscle relaxation (PIR) and therapeutic exercise in female patients with TMDs.~The main goals of using physiotherapy to treat TMDs are to reduce pain, reduce hypertonic muscle hyperactivity and improve tension in hypotonic muscles, restore TMJ joint mobility, and enhance mandibular proprioception and biomechanics. Physiotherapy treatment is usually reversible and non-invasive. Physiotherapy methods generally include physical techniques (laser, ultrasound, currents, heat and cold therapy), manual therapy (soft tissue therapy, joint mobilisations, massage) and therapeutic exercises. Manual therapy and therapeutic exercise in physiotherapy interventions are increasingly being used by clinicians and researched due to positive results in TMJ and some musculoskeletal problems [3].~Scientific papers show the effectiveness of masticatory muscle massage in the treatment of soft tissue disorders, achieving both muscle relaxation, improved tissue blood supply and joint range of motion and reduced pain [4]. Post-isometric relaxation (PIR) is one of the most well-known mobilisation techniques using muscle excitation and inhibition phenomena. It reduces the tension of a muscle or even an entire muscle group, as it inhibits the motoneuron field of a given muscle and thus leads to reflex relaxation. The reason for this is the activation of the Golgi tendon organs during contraction. There are 2 PIR targets - short-term and long-term. The immediate goal is primarily to combat pain and other effects of static muscle overload and to reduce muscle and connective tissue irritation. On the other hand, the long-term goal is to restore the expected length and flexibility of contracted muscles, regain normal joint range of motion and combat joint overload. As a result, post-isometric muscle relaxation is effective in, among other things, treating increased tension and reducing TrPs. It is now widely used in everyday clinical practice for both musculoskeletal therapy and TMDs.~In the daily practice of physiotherapy, it is imperative to make the patient aware of the causes and consequences of the resulting complaints and disorders. In addition to patient education, a key role is played by implementing home self-therapy into the improvement programme, mainly consisting of the systematic performance of therapeutic exercises (TE) individually selected to the patient's condition. Thanks to such management, the patient actively and consciously participates in the healing process and is taught responsibility for their own health.
The study will determinate the influence of four selected physiotherapeutic procedures on the pain intensity, the bioelectrical activity of the masseter muscle, and the range of mandibular mobility in patients with TMDs (temporomandibular joint dysfunction).