Bulk-filled composites are a relatively recent innovation to composite restoratives which allow a clinician to place composites in larger increments than was previously possible. This time savings came with a cost because early bulk filled materials were weaker and less esthetic than traditional composites as they used a lower inorganic filler load in order to increase light transmission. Recent innovations have sought to allow an even greater depth of cure while maintaining important properties such as polishability, strength and handling properties. This increased depth of cure also gives confidence that composites at the cavity walls will receive adequate light for all indications as partially uncured composites have the potential to allow uncured monomers to be released causing inflammation, have reduced mechanical properties and increased leakage. It is therefore advantageous for a bulk-filled composite to cure as well as possible, even in situations in which a curing light output may be lower than expected, a placed composite increment is thicker than estimated, or optimal placement of the curing light tip is difficult.