Now that every composite manufacturer (including the famously conservative 3M™ ESPE™) has released a bulk-fill posterior composite, it’s clear this technique has caught on with dentists, and most likely represents how the majority of Class II posterior composites will be done in the future. With bulk-fill, however, the greatest determinant of success lies more in the curing light than the composite itself. For example, having a near 90-degree head angle and a small vertical head height makes you much more likely to direct light vertically into an MO proximal box on a lower second molar.
The Fusion™ 4.0 Curing Light has that feature and more. For example, most LED curing lights emit light in a pattern with divergence of over 120 degrees, which means the light intensity is significantly weaker at the bottom of a proximal box compared to the top. For a typical Class II restoration with a depth of 4–6 mm, the intensity can drop as much as 80 percent from the top to the bottom layer, resulting in less cure and more sensitivity at the composite/pulpal floor interface. The Fusion 4.0 has patented lens technology that enables consistent power 10 mm from the source of the light, with full wavelength coverage to enable all composite initiators with a five-second cure.
When you consider that you can purchase an optional light head that allows you to perform oral cancer screenings and an optional head to screen for caries, the full power of the Fusion 4.0 Curing Light is hard to deny.