Injection molding has been used in manufacturing for over 150 years, and the concept has recently been introduced into dentistry.
Dental injection molding is a restorative technique that involves injecting a low-viscosity composite resin into a transparent silicone matrix (or stent) created from a wax-up or digital mock-up. This method produces highly aesthetic, minimally invasive restorations, particularly for anterior teeth, diastema closure, and full-arch composite veneers. The silicone matrix helps shape the composite resin, ensuring a predictable and natural-looking outcome.
For achieving a better and stronger dental restoration, it is preferrable to use a heavily filled composite rather than a flowable composite. Warming the composite resin before injection molding improves its flow, reduces micro-leakage, and helps ensure a more reliable restoration. This technique involves heating the composite to a specific temperature, such as 60° C (140° F), to lower its viscosity, making it easier to inject into a mold.
How it Works – Quick Overview
1. Heating the Composite: The composite resin is typically preheated in a special warming device to a temperature between 54° C and 68° C (129° F and 154°F), depending on the specific material and manufacturer instructions.
2. Injection Molding: The warmed composite is then injected into a clear silicone matrix, which has been adapted to the tooth preparation.
3. Curing: The injected composite is the light-cured, hardening and bonding it to the tooth surface.
Warming Benefits for Injection Molding
- Improved Flow: Warming the composite makes it more fluid, allowing it to flow more easily into the mold and into the intricate areas of the tooth preparation
- Reduced Micro-leakage: The improved flow and adaptation of warmed composite can lead to a better seal, reducing the risk of micro-leakage, which is the passage of fluids and bacteria into the tooth cavity.
- Improved Adaptation: Warmed composite can conform more closely to the tooth surface, resulting in a more accurate and esthetic restoration.
- Reduced Extrusion Force: Warming can significantly reduce the force needed to dispense the composite, improving ergonomics and reducing fatigue for the dentist
- Enhanced Aesthetics: By allowing for better adaptation and filling of intricate areas, warming composite can contribute to more esthetically pleasing restorations.
Warmed Composite for Injection Mold – A Demonstration
– Dr. Marc Geissberger, DDS
All Warmed Up
In essence, warming composite for injection molding is a technique that enhances the flow, adaptation, and durability of composite restorations, leading to more predictable and esthetic results.
Keep an eye out for our next email where we highlight our best warming products for injection molding procedures.