Effect of Night Guard Use on Masseter Muscle Thickness in Children With Bruxism

This prospective, single-group follow-up study is designed to evaluate the effects of night guard use on bruxism symptoms and masseter muscle thickness in children aged 10-12 years. A total of 20 children diagnosed with bruxism based on parental reports and clinical examination will be included. Clinical findings, including tooth wear, muscle tenderness, temporomandibular joint findings, and parafunctional habits, will be recorded.

Masseter muscle thickness will be measured bilaterally using ultrasonography under standardized conditions at baseline, 3 months, and 6 months. Following baseline evaluation, a custom-made night guard will be fabricated for each participant and regular use will be recommended.

Changes in clinical symptoms and muscle thickness over time will be analyzed. Ultrasonographic measurements will be performed using a standardized protocol by an experienced dentomaxillofacial radiologist. The study does not include a control group. All procedures are non-invasive and do not involve ionizing radiation.

• Occlusal Splint (Night Guard) (Device): Participants will receive a custom-made night guard and will be instructed to use it regularly during sleep.

Primary outcomes

• Change in masseter muscle thickness [Baseline, 3 months, 6 months]: Change in masseter muscle thickness (measured by ultrasonography)

Secondary outcomes

• Change in bruxism-related clinical symptoms assessed by Wong-Baker Faces Pain Rating Scale [Baseline, 3 months, 6 months]: Changes in bruxism-related symptoms including muscle pain, fatigue, and headache will be assessed using a Wong-Baker Faces Pain Rating Scale (WBFPRS). The WBFPRS consists of a scale ranging from 0 (no hurt) to 10 (hurt worst). Higher scores indicate greater symptom severity.
• Change in temporomandibular joint (TMJ) clinical findings (joint sounds, deviation/deflection, pain on palpation) [Baseline, 3 months, 6 months]: Temporomandibular joint (TMJ) findings will be assessed by clinical examination, including the presence of joint sounds (clicking/crepitation), mandibular deviation or deflection during opening, and pain on palpation. Each finding will be recorded as present or absent. The number of positive findings per participant will be calculated, with higher values indicating greater TMJ involvement.

Sex: All, ages: 10 Years to 12 Years, accepts healthy volunteers

Inclusion Criteria:

1. Children aged 10-12 years
2. Diagnosis of bruxism based on parental report and clinical findings
3. Willingness to participate
4. Parental consent and child assent obtained

Exclusion Criteria:

1. Missing posterior teeth causing unilateral chewing
2. History of psychological disorders
3. Neurological disorders or craniofacial abnormalities
4. Use of medications affecting muscle activity
5. Presence of skeletal malocclusions
6. Ongoing orthodontic treatment