Custom TMJ Prosthetic Implant via 3D Imaging and Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current prosthetic implants for the temporomandibular joint lack long-term durability and are invasive in their surgical procedures, failing to meet the needs of maxillofacial surgery specialists for a non-invasive, long-lasting solution.
Innovation Solution
A prosthetic implant made of rigid materials like ceramic or metal alloys, with a concave porous surface designed to complement the natural joint surfaces, produced using 3D images from medical imaging systems and computer-aided design, allowing for precise milling and chemical etching to enhance osteointegration, and minimizing surgical invasiveness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a ball-and-socket prosthesis is used for TMJ reconstruction, then the complex movements of the natural joint are allowed, but the implantation becomes particularly invasive and the structure is not well-suited to the TMJ
Solution Approach 1:
The prosthesis is divided into two separate components: a condylar prosthesis that replaces the mandibular condyle and a glenoid fossa prosthesis that replaces the temporal bone articular surface. This segmentation allows each component to be optimized for its specific function while reducing the overall surgical invasiveness compared to a single ball-and-socket unit.
Solution Approach 2:
The condylar prosthesis features a convex articular surface that replicates the natural condyle geometry, while the glenoid fossa prosthesis provides a concave receiving surface. This local quality optimization ensures proper articulation and movement while minimizing invasive preparation of the surrounding bone structures.
2Object-affected harmful factors
If a mini condyle prosthesis is used to avoid ablation of the condyle, then surgical invasiveness is reduced, but the implantation requires forming a shoulder to receive the upper end of the natural condyle
Solution Approach 1:
The glenoid fossa prosthesis is pre-formed with a receiving cavity that accommodates the natural condyle without requiring additional surgical preparation. This preliminary action eliminates the need for intraoperative shoulder formation while maintaining the non-ablative approach to the condyle.
3Adaptability or versatility
If a flexible plastic meniscal endoprosthesis is used, then the prosthesis can be adapted to the shape of the TMJ, but the durability is doubtful and it cannot be attached to muscles or ligaments
Solution Approach 1:
The prosthesis material transitions from flexible plastic to rigid ceramic or metal alloy, fundamentally changing the mechanical parameters of the implant. This material parameter change provides superior durability and load-bearing capacity while maintaining the ability to be customized to the patient's anatomy through 3D imaging and computer-aided design.
Solution Approach 2:
The prosthesis utilizes composite construction with a rigid ceramic or metal alloy articular surface combined with a porous coating layer. This composite structure provides both the durability of rigid materials and the osteointegration benefits of porous surfaces, overcoming the limitations of flexible plastic options.
4Reliability
If a rigid prosthetic implant is used instead of flexible material, then durability is improved, but the manufacturing precision must be extremely high to ensure precise fit
Solution Approach 1:
The prosthesis is designed using 3D images obtained from medical imaging (CT scans, MRI) of the patient's anatomy. Computer-aided design software creates a virtual model that is precisely copied to the physical prosthesis through additive manufacturing or precision machining. This digital copying process ensures manufacturing precision that would be impossible to achieve through traditional methods.
Solution Approach 2:
The manufacturing process replaces traditional mechanical measurement and fitting methods with digital 3D modeling and computer-controlled manufacturing. This substitution of mechanical systems with digital systems enables the production of rigid prostheses with extremely high precision while maintaining long-term durability.
5Stability of the object's composition
If traditional implantation methods are used, then the prosthesis can be secured in position, but the surgical procedure is complex and time-consuming
Solution Approach 1:
The glenoid fossa prosthesis incorporates a self-tapping threaded screw that automatically creates its own anchorage in the temporal bone without requiring separate fixation components or complex securing procedures. This self-service feature simplifies the surgical process while ensuring stable prosthesis positioning.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The implant provides long-term functionality with reduced surgical invasiveness by precisely matching the joint surfaces, ensuring stability and durability without the need for condyle preparation, addressing the limitations of existing flexible material implants.
Implementation Method 1
a concave porous surface designed to complement the natural joint surfaces, produced using 3D images from medical imaging and computer-aided design to ensure precise fit and osteointegration
Data Source
AI summary
The prosthetic temporomandibular implant (10) comprises a concave surface (16) and a convex surface (17) designed to cooperate, respectively, with the natural outer surface (9) of the condyle (5) and the natural inner surface (7) of the fossa (8) of a damaged joint (2) of a human mandible (1). It is made of a rigid biocompatible material such as ceramic, stainless steel or an aluminum/zirconium alloy. The implant is designed based on an image of the joint (2) generated by a medical imaging system and incorporating an image of a healthy joint (3); these three-dimensional images are processed by a CAD (segmentation, vectorization) system to obtain a vector representation of the implant (10) and a data file capable of controlling a digital milling machine. The invention is applicable to the restoration of a damaged TMJ (2).