The Effectiveness of Different Therapeutic Jaw Position Determining Methods in Repositioning Splint Therapy for Temporomandibular Joint Disk Displacement Without Reduction：A Randomized Controlled Clinical Trial

NCT ID: NCT07090772

Last Updated: 2025-07-29

Basic Information

• Recruitment Status: ENROLLING_BY_INVITATION
• Clinical Phase: NA
• Total Enrollment: 45 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-07-20
• Study Completion Date: 2026-08-20

Brief Summary

The goal of this clinical trial is to learn if different therapeutic jaw position determining methods influence the efficacy of repositioning splint therapy for temporomandibular joint disk displacement without reduction. The main questions it aims to answer are:

Does different therapeutic jaw position determining methods influence the efficacy of repositioning splint therapy for temporomandibular joint disk displacement without reduction? Researchers will compare the efficacy of repositioning splint therapy made with different therapeutic jaw position determining methods for temporomandibular joint disk displacement without reduction.

Participants will:

Take repositioning splint made with different therapeutic jaw position determining methods every day for 3-6 months.

Visit the clinic once every 3 weeks for checkups and tests.

Conditions

Temporomandibular Disorder (TMD)

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

receive repositioning splint therapy with jaw position determined by mechanical articulator

Participants will receive repositioning splint therapy with jaw position determined by mechanical articulator method for 3-6 months.

Group Type: EXPERIMENTAL

Repositioning splint therapy with jaw position determined by mechanical articulator

Intervention Type: PROCEDURE

The therapeutic jaw position will be determined by the following steps:

1. Pre-treatment Jaw Position Recording Participants were seated upright with relaxed posture, eyes facing forward, and the Frankfort plane parallel to the floor. Intercuspal position (ICP) was recorded using silicone registration material. Edge-to-edge position of central incisors was recorded for protrusive position. Left/right lateral positions were recorded with opposing canines aligned.

2. Transfer of Jaw Positions Following the manufacturer's protocol for the Artex CR mechanical facebow (Amann Girrbach, Austria) to transfer Participants' jaw positions.

3. Determination of Therapeutic Position The Glenoid fossa was divided into 7 grids in the oblique-sagittal plane using Gelb's method, identifying grid 4 (Gelb 4/7) as the target condylar position.Condylar displacement knobs were set per VTO analysis.

Incisal pin height was increased to establish vertical dimension.

receive repositioning splint therapy with jaw position determined by ai-assisted virtual articulator

Participants will receive repositioning splint therapy with jaw position determined by ai-assisted virtual articulator.

Group Type: EXPERIMENTAL

Repositioning splint therapy with jaw position determined by ai-assisted virtual articulator

Intervention Type: PROCEDURE

The jaw position was determined by the following steps:

1. AI-Based Segmentation and Reconstruction of Jaw Models CBCT DICOM data was imported into an ai-based craniomaxillofacial bone segmentation system to reconstruct 3D models of the jaws and dentition. The mandibular/maxillary bone models and dental arches were exported as .ply files. These .ply files were then imported into Exocad software.

2. Virtual Transfer of Jaw Positions Bilateral AI-segmented medial pole points of the condyles and the right infraorbital point were annotated in cross-sectional views.A virtual articulator was added and registered to the facebow's reference planes and hinge axis. (3)Determination of Therapeutic Position Sagittal joint spaces (anterior/superior/posterior) were measured on cross-sectional views. The composite mandibular model was repositioned to the target occlusion using the "Move Mesh" function based on: Optimal mean joint space measurements and physiological condylar position.

receive repositioning splint therapy with jaw position determined by ai-assisted virtual patient

Participants will receive repositioning splint therapy with jaw position determined by ai-assisted virtual patient

Group Type: EXPERIMENTAL

Repositioning splint therapy with jaw position determined by ai-assisted virtual patient

Intervention Type: PROCEDURE

The jaw position was determined by the following steps:

1. AI-Based Segmentation and Reconstruction of Virtual Patients:

CBCT DICOM data was imported into an ai-based craniomaxillofacial bone segmentation system to reconstruct 3D models of the jaws and dentition. The trajectory of mandibular movement was recorded by an electronic facebow.

2. Virtual Transfer of Jaw Positions Bilateral AI-segmented medial pole points of the condyles and the right infraorbital point were annotated in cross-sectional views.A virtual articulator was added and registered to the facebow's reference planes and hinge axis. (3)Determination of Therapeutic Position Sagittal joint spaces (anterior/superior/posterior) were measured on cross-sectional views. The therapeutic position was determined based on: Optimal mean joint space measurements, physiological condylar position and optimal trajectory of mandibular movement.

Interventions

Repositioning splint therapy with jaw position determined by mechanical articulator

The therapeutic jaw position will be determined by the following steps:

1. Pre-treatment Jaw Position Recording Participants were seated upright with relaxed posture, eyes facing forward, and the Frankfort plane parallel to the floor. Intercuspal position (ICP) was recorded using silicone registration material. Edge-to-edge position of central incisors was recorded for protrusive position. Left/right lateral positions were recorded with opposing canines aligned.

2. Transfer of Jaw Positions Following the manufacturer's protocol for the Artex CR mechanical facebow (Amann Girrbach, Austria) to transfer Participants' jaw positions.

3. Determination of Therapeutic Position The Glenoid fossa was divided into 7 grids in the oblique-sagittal plane using Gelb's method, identifying grid 4 (Gelb 4/7) as the target condylar position.Condylar displacement knobs were set per VTO analysis.

Incisal pin height was increased to establish vertical dimension.

Intervention Type: PROCEDURE

Repositioning splint therapy with jaw position determined by ai-assisted virtual articulator

The jaw position was determined by the following steps:

1. AI-Based Segmentation and Reconstruction of Jaw Models CBCT DICOM data was imported into an ai-based craniomaxillofacial bone segmentation system to reconstruct 3D models of the jaws and dentition. The mandibular/maxillary bone models and dental arches were exported as .ply files. These .ply files were then imported into Exocad software.

2. Virtual Transfer of Jaw Positions Bilateral AI-segmented medial pole points of the condyles and the right infraorbital point were annotated in cross-sectional views.A virtual articulator was added and registered to the facebow's reference planes and hinge axis. (3)Determination of Therapeutic Position Sagittal joint spaces (anterior/superior/posterior) were measured on cross-sectional views. The composite mandibular model was repositioned to the target occlusion using the "Move Mesh" function based on: Optimal mean joint space measurements and physiological condylar position.

Intervention Type: PROCEDURE

Repositioning splint therapy with jaw position determined by ai-assisted virtual patient

The jaw position was determined by the following steps:

1. AI-Based Segmentation and Reconstruction of Virtual Patients:

CBCT DICOM data was imported into an ai-based craniomaxillofacial bone segmentation system to reconstruct 3D models of the jaws and dentition. The trajectory of mandibular movement was recorded by an electronic facebow.

2. Virtual Transfer of Jaw Positions Bilateral AI-segmented medial pole points of the condyles and the right infraorbital point were annotated in cross-sectional views.A virtual articulator was added and registered to the facebow's reference planes and hinge axis. (3)Determination of Therapeutic Position Sagittal joint spaces (anterior/superior/posterior) were measured on cross-sectional views. The therapeutic position was determined based on: Optimal mean joint space measurements, physiological condylar position and optimal trajectory of mandibular movement.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Aged 13-50 years, with permanent dentition, possessing full autonomy in behavior and expression;
• Meeting the 2014 Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) diagnostic standards for irreducible temporomandibular joint disc displacement;
• MRI-confirmed unilateral irreducible disc displacement: At maximum intercuspation: Posterior band of disc located anterior to the 11:30 position, intermediate zone anterior to condyle; At maximum mouth opening: Intermediate zone remains anterior to condyle.

Exclusion Criteria

• Systemic diseases, psychiatric disorders, or impaired consciousness;
• Pain-only disorders without articular pathology signs;
• Mandibular hypoplasia, TMJ tumors, or prior TMJ trauma;
• History of definitive TMJ disorder treatment.

• Minimum Eligible Age: 13 Years
• Maximum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fujian Medical University

OTHER

Sponsor Role: lead

Responsible Party

Hao Yu

Director; Clinical Professor; dean of overseas education college; vice dean of school and hospital of stomatology

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Hao Yu, PhD, MD

Role: PRINCIPAL_INVESTIGATOR

Fujian Medical University, China

Locations

Fujian Medical University

Fuzhou, Fujian, China

Countries

China

Other Identifiers

2025ECSS057

Identifier Type: -

Identifier Source: org_study_id