Effects of Occlusal Imbalance and Clenching on Balance in Stroke Patients

This randomized controlled study will be conducted on a minimum of 42 stroke patients who meet the inclusion and exclusion criteria. Patients included in the study will be randomly assigned to one of three groups: the ipsilateral side stimulated occlusal imbalance group, the contralateral side stimulated occlusal imbalance group, or the bilateral jaw clenching group.

• Ipsilesional Side Stimulated Occlusal Imbalance (Other): In this group, a 1 cm thick cotton roll will be placed on the ipsilesional occlusal surfaces of the patients, and they will be instructed to hold it in place without clenching.
• Contralesional Side Stimulated Occlusal Imbalance (Other): In this group, a 1 cm thick cotton roll will be placed on the contralesional occlusal surfaces of the patients, and they will be instructed to hold it in place without clenching.
• Bilateral Cotton Roll with Jaw Clenching (Other): In this group, a 1 cm thick cotton roll will be placed on both occlusal surfaces, and the patients will then be instructed to clench their teeth.

Primary outcomes

• Overall Postural Stability Index Measurement [Change from baseline overall postural stability index immediately after the intervention]: This index will be assessed by measuring deviations of the center of gravity in the anteroposterior and mediolateral directions. Lower scores indicate smaller deviations and better postural stability. The test will be performed on a stable platform with two trials of 30 seconds each. The average of the two trials will be automatically calculated by the TechnoBody balance system.
• Fall Risk Assessment [Change from baseline fall risk immediately after the intervention]: Fall risk will be assessed by measuring the patient's ability to maintain balance on an unstable platform. Based on their ability to maintain balance, a fall risk score will be generated, with higher scores indicating a greater risk of falling. The test will be performed with two 30-second trials. The average of the two trials will be calculated automatically by the TechnoBody balance system.

Secondary outcomes

• Anteroposterior Stability Index Measurement [Change from baseline anteroposterior stability index immediately after the intervention]: The anteroposterior stability index will be assessed by measuring deviations of the center of gravity in the anteroposterior direction. Lower scores indicate smaller deviations and better anteroposterior postural stability. The test will be performed on a stable platform with two trials of 30 seconds each. The average of the two trials will be automatically calculated by the TechnoBody balance system.
• Mediolateral Stability Index Measurement [Change from baseline mediolateral stability index immediately after the intervention]: The mediolateral stability index will be assessed by measuring deviations of the center of gravity in the mediolateral direction. Lower scores indicate smaller deviations and better mediolateral postural stability. The test will be performed on a stable platform with two trials of 30 seconds each. The average of the two trials will be automatically calculated by the TechnoBody balance system.
• Weight Bearing Distribution Assessment [Change from baseline weight bearing distribution immediately after the intervention]: Weight-bearing distribution will be assessed by measuring the percentage of body weight borne by each limb during quiet standing. Lower asymmetry values indicate more balanced weight distribution and better postural stability. The test will be performed on a stable platform with two trials of 30 seconds each. The average of the two trials will be automatically calculated by the TechnoBody balance system.

Sex: All, ages: 18 Years to 75 Years

Inclusion Criteria:

* Having chronic stroke,
* A Mini-Mental State Examination score of 24 or higher,
* Being between 18 and 75 years of age,
* Having a Brunnstrom stage of 4 or above,
* Ability to stand independently for 20 seconds or more,
* Ability to walk independently for 10 meters, using assistive devices or orthoses if necessary,
* Having opposing mandibular and maxillary second premolars or first molars

Exclusion Criteria:

* The presence of severe osteoarthritis in the lower extremity,
* The presence of cancer or diabetic neuropathy,
* The presence of vestibular disorder,
* The presence of lower extremity ulceration or amputation,
* Hemodynamic instability,
* The presence of other neurological disorders (such as multiple sclerosis, Parkinson's disease),
* Having experienced an acute lower extremity injury in the last six weeks,
* History of lower extremity surgery,
* Alcohol consumption in the last 24 hours
* Posterior circulation stroke involving the basilar artery or cerebellum

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• ömer dursun, Asst. Prof., Principal investigator, Bitlis Eren University
• burak mavuş, M.Sc., Principal investigator, Bolu Abant İzzet Baysal Physiotherapy and Rehabilitation Training and Research Hospital