5 new ways to squeeze the most out of your automix syringe

For many, automix syringes are the preferred delivery method for resin cements. They deliver a consistent, high-quality mix and allow direct application to the restoration or preparation. While these efficiency benefits typically come with a material waste trade-off, new developments now allow for even better handling while minimizing both material and plastic waste. Check out five recent improvements to the automix syringe that could help improve your procedure.

First Improvement: Mixing tips that minimize material waste

Automix syringes use static mixers in the tip to combine the two cement components – often referred to as catalyst and base paste – into one homogeneous paste. By design, some paste is left in the mixer. With standard systems, around 0.35 grams of paste is left in the mixer, while only around 0.16 grams of material is used for a crown.1 This means almost double the material used is left in the tip!

Figure 1: Typical mixing tips for standard automix syringes versus 3M™ RelyX™ Universal Cement Micro Mixing Tip (right).

To address the issue of material waste, 3M designed a proprietary syringe and micro mixing tip for 3M™ RelyX™ Universal Resin Cement (IMAGE CAPTION: Figure 1). The shorter mixing tip reduces material waste to as little as 0.07 grams – an 80% reduction – while still offering excellent mixing quality. Therefore, while the syringe contains only 3.4 grams of resin cement, it can deliver a similar number of applications as the other systems.¹

Second Improvement: An ergonomic, barrel shaped automix syringe

The dramatic reduction in material waste in the 3M™ RelyX™ Universal Resin Cement Micro Mixing Tip means that far less resin cement is needed for the 15 applications expected from a full-size automix syringe. This material savings created an opportunity for 3M to rethink the design of the syringe body. Instead of using a long double barrel design, 3M opted for the ergonomic advantages of a smaller, shorter design similar to a flowable composite syringe.

Figure 2: 3M™ RelyX™ Universal Resin Cement Automix Syringe

The two paste compartments of the RelyX Universal Resin Cement automix syringe are fully enclosed in a cylindrical shape that smoothly flows into a comfortable finger rest.
This shape makes it possible to grip the syringe at any angle to reach the application area ( Figure 2). Due to the small size of the syringe, the distance between the hand and the tip is reduced, which supports precise application of the material. The syringe design was recognized with the prestigious Red Dot Design Award in 2021.

Third Improvement: Half the plastic waste

Large amounts of waste are generated in dental offices around the world. As a company that applies science to shape a world with less waste, 3M supports steps towards more environment-friendly procedures in the dental practice. ²
In addition to the 80% reduction in material waste, the smaller mixing tip and smaller syringe body of RelyX Universal Resin Cement represent a 50% reduction in plastic waste per application (fig 3). The new syringe also makes the closing cap of current automix syringes obsolete – that’s one less piece of plastic in the trash.

Figure 3: Syringe size and 15 mixing tips volume comparison of 3M™ RelyX™ Universal Resin Cement (left) vs. a standard automix syringe.

Fourth Improvement: Better hygiene control

Unlike standard automix syringes that have edges and crevices, the RelyX Universal Resin Cement syringe has a smooth surface design that is easier to clean. Furthermore, the entire syringe tip is enclosed in the mixing tip during use, protecting the syringe opening from contamination.

Figure 4: Front view of the 3M™ RelyX™ Universal Resin Cement syringe sealed by the valve at the tip.

Finally, the barrels of standard automix syringes are open and are typically stored with the used mixing tip left on to ensure sealing. The RelyX Universal Resin Cement syringe is different. It is equipped with a valve mechanism that cleanly seals the syringe and allows for hygienic storage without the used tip (fig 4). The mixing tip serves as the key that opens and closes the valve as shown in Figure 5.

Figure 5: Close-up of the 3M™ RelyX™ Universal Cement syringe tip with closed valve (top left, A). Disassembled view of valve and syringe body with the two openings for paste extrusion exposed (top right, B). Mixing tip mounted on closed valve (C1), mixing tip rotation gradually opens valve (C2), fully open state ready for paste extrusion at 90° rotation (C3). Removing the tip requires rotating it back into the initial position, which closes the valve.

Fifth Improvement: Enhanced ease of use with fewer components

Standard automix systems come with a straight or “regular” mixing tip and a wide tip with two attachments – one for intraoral application and one for endodontic application. These are four components that need to be kept handy and replenished (fig 6).

Figure 6: Four mixing tip components for the standard automix syringe (left) vs. two mixing tip components for 3M™ RelyX™ Universal Resin Cement

RelyX Universal Resin Cement, however, only needs two components: one mixing tip and one elongation tip. The RelyX Universal Micro Mixing Tip has a short, bent nozzle that allows easy application for restorations and preparations. The elongation tip can be directly attached. This reduces the number of mixing tip components in half, helping declutter inventory.

Figure 7: Side-by-side comparison of the standard elongation tip attachment (left) and the RelyX Universal Micro Mixing Tip with elongation tip (right).

In addition, the elongation tip that fits the RelyX Universal Micro Mixing Tip is longer and thinner than the current standard endo tip attachment, allowing for easier root canal application (fig 7).

Conclusion

The RelyX Universal Resin Cement automix syringe delivers five impressive improvements in material savings, reduction of plastic waste, ergonomics, hygiene, and ease of use. These improvements tackle the shortcomings of today’s standard automix syringes and help take automixing resin cements to the next level.