Clinical Accuracy of Patient-specific Implants in Genioplasty

Study Overview
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Brief Summary
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The purpose of this study is to assess the accuracy and clinical validation of patient specific implants (PSI) technique for genioplasty.

Detailed Description
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Chin plays an important role in the lower facial harmony and balance. With the advances in computer-aided surgical simulation (CASS) technology, surgeons are now able to simulate surgical procedures in the computer to achieve the best possible surgical plan. However, CAD/CAM surgical templates do not maximize the potential of CASS technique. Patient specific implants (PSI) has rapidly developed in cranio-maxillofacial surgery in the past few years. However, few studies have introduced PSI technique in osseous genioplasty. The purpose of this study is to assess the accuracy and clinical validation of patient specific implants (PSI) technique in genioplasty for positioning and fixation of the chin segment. Anticipated 30 patients with chin deformities are enrolled. Virtual planning is performed with the computer-aided surgical simulation method. The 3D printing titanium cutting guide and patient specific plate is involved in this PSI method. The cutting guide is designed to guide the osteotomy and screw holes drilling for the following patient specific plate. And the patient specific plate is used to simultaneously complete the reposition and fixation of the chin. The outcome is evaluated by comparing the plan with actual outcomes.

Official Title
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The Application and Clinical Accuracy of Patient-specific Implants in Genioplasty

Conditions
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Genioplasty, Chin Microgenia, Chin Macrogenia

Intervention / Treatment
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* Device: Patient Specific Implant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients who were scheduled to undergo genioplasty; patients who were scheduled to undergo CT scan as a part of their diagnosis and treatment; patients who agreed to participate in this study Exclusion Criteria: craniofacial syndrome; segmental osseous genioplasty; previous osseous genioplasty; previous mandibular trauma; systemic disorders.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PSI group<br>The patient specific implant (PSI) is used to completed the genioplasty. | Device: Patient Specific Implant<br>* The patient specific implant is used to simultaneously complete the reposition and fixation of the chin.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positional differences of the chin between the plan and postoperative results | The coordinates of the centroid of three land points on the chin segment was used to calculate the position differences between the plan and postoperative results in X, Y and Z axis. | 2 weeks after the operation | 
| Orientation differences of the chin between the plan and postoperative results | The coordinates of three independent points were used to define the orientation of the chin in 3D space. The orientation differences were calculated in pitch (the rotation around the X axis), roll (the rotation around the Y axis), and yaw (the rotation around the Z axis). | 2 weeks after the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| time consuming | time spending for the virtual planning and the design of the PSI | 3 days after the operation | 
| economic consuming | economic cost of the fabrication of the patient specific implant | 3 days after the operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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patient specific implant, computer-aided surgery, clinical accuracy