Accuracy of Digital Mandibular Repositioning in Occlusal Reconstruction for Patients With Disc Displacement

NCT07345104 | Completed

• 1 other identifier: 2024GGA070
• Study Type: interventional
• Target: 48
• Locations: 1 country
• Sites: 1

Brief Summary

This study evaluates a new, individualized treatment for adolescents with temporomandibular joint disorders (TMD) caused by bilateral, reducible disc displacement. Participants will undergo clinical and imaging examinations, including cone-beam CT (CBCT), MRI, and intraoral digital scanning to create three-dimensional models of the teeth and jaw. Based on these data, the study team will design and fabricate a personalized repositioning digital occlusal splint for each participant. Patients will be instructed on how to wear the splint and will return for regular follow-up visits to monitor symptoms and adjust the splint as needed. The study aims to improve pain, chewing function, and overall quality of life. All research-related imaging, digital scans, splint fabrication, and follow-up visits will be provided at no cost to participants. Possible risks include temporary discomfort or pressure when first wearing the splint, and the possibility that symptoms may not improve as expected. Participant safety, privacy, and data confidentiality will be strictly protected, and participants may withdraw from the study at any time without affecting their future medical care.

Conditions

Temporomandibular Joint Disc Displacement

Keywords

Reducible disc displacement; Mandibular repositioning; Occlusal splint therapy; Digital dentistry; CBCT; Electronic facebow

Outcome Measures

Primary Outcomes (2)

• Change in Temporomandibular Joint Space Ratio

  Quantitative assessment of changes in temporomandibular joint space using Cone Beam Computed Tomography (CBCT) with Ikeda's method.

  Baseline and 3 months post-treatment

• Change in Disc-Condyle Relationship Angle

  Quantitative assessment of disc displacement using Magnetic Resonance Imaging (MRI) with angle measurement technique.

  Baseline and 3 months post-treatment

Study Arms (4)

Intraoral Direct Positioning

ACTIVE COMPARATOR

Therapeutic mandibular position is determined using the clinical clicking elimination method. Patients perform wide opening until clicking occurs, then gradually retract the mandible while making opening-closing movements to identify the minimal protrusion position without clicking. A repositioning splint is fabricated based on this position.

Device: Clinical Clicking Elimination Repositioning Splint

Articulator Positioning

EXPERIMENTAL

Therapeutic mandibular position is determined using a semi-adjustable articulator (Artex CR) with mechanical facebow transfer. Condylar guidance angles are obtained from protrusive and lateral excursion records. The optimal position is calculated based on CBCT joint space measurements and MRI disc displacement data. A repositioning splint is fabricated accordingly.

Device: Adjustable Articulator Repositioning Splint

Digital Anatomical Positioning

EXPERIMENTAL

Therapeutic mandibular position is determined by integrating intraoral scanning data with CBCT-reconstructed 3D jaw models using CAD software (Exocad). The optimal position is calculated by referencing MRI disc reduction phase, ideal joint space ratios (anterior:superior:posterior = 1:1.3:1), and anatomical landmarks. A repositioning splint is digitally designed and 3D-printed.

Device: CAD-Designed Anatomical Repositioning Splint

Digital Jaw Motion Tracking

EXPERIMENTAL

Therapeutic mandibular position is determined by integrating 3D jaw models with electronic jaw tracking data (Zebris JMA system). The optimal position is identified by analyzing condylar movement trajectories, specifically locating the crossover points of the "figure-8" pattern indicating disc displacement, combined with dynamic MRI and joint space parameters. A repositioning splint is digitally designed and 3D-printed.

Device: Electronic Jaw Tracking Repositioning Splint

Interventions

Clinical Clicking Elimination Repositioning Splint DEVICE

A custom-fabricated hard acrylic repositioning splint based on manual intraoral mandibular positioning. The splint is created by: 1. Clinically identifying the optimal jaw position through clicking elimination technique 2. Taking alginate impressions of maxillary and mandibular arches 3. Pouring stone models and manually adjusting mandibular model to the determined position 4. Fabricating a hard acrylic splint with 1-2 mm occlusal clearance 5. Finishing and polishing the splint Patients wear the splint 24 hours daily (except during meals) for 3 months, with adjustments at 2 weeks, 1 month, 2 months, and 3 months.

Intraoral Direct Positioning

Adjustable Articulator Repositioning Splint DEVICE

A custom-fabricated hard acrylic repositioning splint using adjustable articulator (Artex CR) methodology: 1. Performing mechanical facebow transfer 2. Recording condylar guidance parameters in protrusive and lateral excursions 3. Analyzing CBCT joint space measurements and MRI disc displacement data 4. Mounting study models on Artex CR articulator with precise condylar settings 5. Manually adjusting splint to achieve optimal mandibular position 6. Fabricating hard acrylic splint with 1-2 mm occlusal clearance Patients wear the splint 24 hours daily (except during meals) for 3 months, with adjustments at 2 weeks, 1 month, 2 months, and 3 months.

Articulator Positioning

CAD-Designed Anatomical Repositioning Splint DEVICE

A digitally designed and 3D-printed repositioning splint using advanced digital workflow: 1. Performing intraoral digital scanning (iTero Element) 2. Acquiring CBCT scan (I-CAT FLX) 3. Importing MRI disc displacement data 4. Using CAD software (Exocad) to: * Overlay intraoral scan with CBCT 3D model * Reference MRI disc reduction phase * Calculate optimal joint space ratios 5. Digitally designing splint with precise mandibular positioning 6. Fabricating hard acrylic splint with 1-2 mm occlusal clearance Patients wear the splint 24 hours daily (except during meals) for 3 months, with adjustments at 2 weeks, 1 month, 2 months, and 3 months.

Digital Anatomical Positioning

Electronic Jaw Tracking Repositioning Splint DEVICE

A digitally designed repositioning splint using electronic jaw motion tracking: 1. Performing 3D jaw motion tracking (Zebris JMA system) 2. Capturing mandibular movement trajectories 3. Identifying "figure-8" pattern crossover points indicating disc displacement 4. Integrating dynamic MRI data 5. Analyzing optimal joint space parameters 6. Using CAD software to design precise mandibular positioning splint 7. Fabricating hard acrylic splint with 1-2 mm occlusal clearance Patients wear the splint 24 hours daily (except during meals) for 3 months, with adjustments at 2 weeks, 1 month, 2 months, and 3 months.

Digital Jaw Motion Tracking

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Diagnosis of reducible temporomandibular joint (TMJ) disc displacement according to the 2014 revised criteria of the International Association for Dental Research;
• Bilateral reducible disc displacement confirmed by MRI;
• Reproducible joint clicking during mandibular opening and closing;
• Permanent dentition with full cognitive and communicative ability;
• Signed informed consent with good treatment compliance.

You may not qualify if:

• Non-reducible disc displacement, osteoarthrosis, isolated myofascial pain, or other conditions not meeting diagnostic criteria;
• Receipt of other TMJ disorder treatments within the past 3 months;
• Presence of systemic diseases, psychiatric disorders, or impaired consciousness.

Sponsors & Collaborators

• Fujian Medical University: lead

Study Sites (1)

School and Hospital of Stomatology, Fujian Medical University,

Fuzhou, Fujian, 350000, China

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Blinding and Masking Procedures: 1. Outcome Assessor Blinding * All clinical and radiographic outcome measurements will be performed by independent assessors who are unaware of the participant's group allocation. * Participants will be assigned unique, randomly generated identification codes that do not reveal group assignment. * Radiographic images (CBCT and MRI) will be anonymized and presented in a randomized order to blinded radiologists. 2. Limitations of Masking o Complete blinding is not possible due to the distinct nature of interventional approaches: a) Participants will be aware of their specific mandibular repositioning technique b) Clinicians performing interventions cannot be blinded due to different positioning methods 3. Blinding Process for Outcome Assessment o Clinical outcome measures (Craniomandibular Index, Joint Movement Assessment) will be evaluated by a research assistant not involved in the intervention.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor & Associate Dean, Dept. of Prosthodontics, Fujian Medical University; Adjunct Associate Professor, Dept. of Applied Prosthodontics, Nagasaki University, Nagasaki, Japan.

Model Details: Participants are assigned to one of four parallel groups based on patient preference and clinical feasibility (non-randomized allocation): * Group A (Intraoral Direct Positioning): Therapeutic mandibular position determined by clinical clicking elimination method. * Group B (Articulator Positioning): Therapeutic position determined using semi-adjustable articulator with facebow transfer and condylar guidance records. * Group C (Digital Anatomical Positioning): Therapeutic position determined by integrating intraoral scanning, CBCT, and MRI data using CAD software. * Group D (Digital Jaw Motion Tracking): Therapeutic position determined

Study Record Dates

• First Submitted: December 22, 2025
• First Posted: January 15, 2026
• Study Start: June 20, 2025
• Primary Completion: December 20, 2025
• Study Completion: December 20, 2025
• Last Updated: February 11, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)