The Fixed Pin Model is an advanced dental working model technique widely used for creating accurate restorations, such as dental bridges, implants, and other high-precision prostheses. By inserting fixed metal pins into the model, specific areas (e.g., prepared teeth) can be detached and reattached with exact positioning, ensuring precision during fabrication.
Why is the Fixed Pin Model Important?
In dental restorations, model accuracy directly affects the outcome of the prosthesis. Traditional models may shift during adjustments, leading to errors in fit or occlusion. The Fixed Pin Model addresses this by providing detachable yet stable positioning, making it a reliable solution for precision-driven restorations.
How to Create a Fixed Pin Model
1. Take the Dental Impression
Start by capturing an impression of the patient’s mouth using materials like silicone rubber. This ensures detailed and accurate replication of the teeth and gingiva.
2. Pour the Stone Model
Carefully pour high-strength dental stone into the impression to create the working model. Avoid bubbles or defects during this process for optimal accuracy.
3. Plan the Detachable Areas
Mark the sections of the model that need to be detachable, typically the areas around prepared teeth. These sections will later accommodate restorations like crowns or bridges.
4. Drill Holes and Insert Pins
This step is the cornerstone of the Fixed Pin Model:
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Drilling: Use a laser pin drill machine to drill precise holes into the base of the marked sections.
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Inserting Pins: Place metal pins into the drilled holes. The pins must be of appropriate length and securely fit to allow stable detachment and repositioning.
5. Segment and Separate the Model
Using Mr. Bur Diamond Disc Series, carefully separate the marked sections from the base. Key considerations include:
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Ensuring smooth cutting surfaces to prevent damage.
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Maintaining alignment between the detachable sections and the main model base.
The separated sections can now be freely removed and repositioned with the help of the fixed pins.
6. Grind a Groove
After drilling, dental technicians grind a groove near the hole using Mr. Bur Tungsten Carbide Laboratory Series Medium Cross Cut / Medium Plain Cut to enhance pin stability, prevent movement of the separated model section, facilitate post-insertion adjustments, and reduce the risk of model fracture by:
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Providing additional support to prevent loosening or rotation
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Acting as a locking mechanism to restrict displacement
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Distributing stress evenly to minimize cracks or breaks.
Recommended Burs: TC1, TC3, TC6 and TC21
Dental technicians can select the appropriate bur shapes, coarseness and sizes based on their specific preferences and model requirements to achieve optimal precision and efficiency.
7. Fabricate the Restoration
Technicians can work on the detachable sections independently. For example, during bridge fabrication, the prepared teeth can be adjusted or scanned without disturbing the rest of the model. This ensures precise occlusion and marginal fit.
8. Reposition and Verify
After processing, reattach the detachable sections to the base to check for accuracy. Repeat adjustments and verifications until the restoration meets all clinical requirements.
Advantages of the Fixed Pin Model
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High Precision The fixed pins ensure that detachable sections maintain consistent positioning, eliminating errors caused by misalignment.
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Convenience for Technicians By isolating specific sections, technicians can work on smaller, manageable areas without compromising the integrity of the entire model.
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Efficient Repositioning Detachable sections can be reattached quickly and accurately, saving time during adjustments.
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Ideal for Complex Restorations The Fixed Pin Model is particularly useful for multi-unit bridges, implant-supported restorations, and other high-precision prostheses.
Applications of the Fixed Pin Model
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Dental Bridges In multi-unit bridge design, the Fixed Pin Model ensures precise alignment of abutment teeth, reducing occlusal errors.
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Implant Restorations The detachable sections simplify adjustments and design for implant-supported prostheses.
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Precision Attachments For removable dentures or intricate clasp designs, the Fixed Pin Model guarantees accurate fabrication.
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Digital Dentistry with CAD/CAM When paired with digital scanning, detachable sections can be independently scanned or processed, enhancing the accuracy of CAD/CAM workflows.
Limitations of the Fixed Pin Model
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Complex Production Creating a Fixed Pin Model requires specialized tools and expertise, making it more complicated than traditional models.
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Higher Costs The materials and labor involved in this technique often result in increased costs compared to simpler methods.
The Fixed Pin Model is an invaluable technique for achieving precision and efficiency in dental restorations. Utilizing high-quality tools such as Mr. Bur Tungsten Carbide Laboratory Series and Diamond Disc Series ensures accurate positioning, enhances workflow efficiency, and supports complex prosthetic designs. Are you ready to elevate your dental restoration process with the precision and reliability of Mr. Bur products.
Diamond Burs, Carbide Burs, Surgical & Lab Use Burs, Endodontic burs, IPR Kit, Crown Cutting Kit, Gingivectomy Kit, Root Planning Kit, Orthodontic Kit, Composite Polishers, High Speed Burs, Low Speed Burs
