Light curing may not be as simple as it seems: again!

In a Comment in 2011, I drew readers' attention to a number of problems associated with Light Curing Units (LCUs), today an essential part of the dental clinicians' armamentarium. These included deficiencies in the disinfection of LCUs, and anxieties regarding the delivery of sufficient light energy to a given resin composite restoration.¹ Given that the use of resin composite restorations is increasing² and will continue to increase as the phasedown in the use of amalgam gathers pace, the optimum use of an LCU will become increasingly relevant.

In lecturing engagements, I have had occasion to ask the question – Do you ever check the intensity of your LCU? Generally, a small proportion of hands go up and, when the supplementary question is asked, – Do you think you should?, everyone agrees that they should! Not that I am trying to make people feel guilty, but this is nothing new! In a survey conducted by the FGDP (UK), fewer than 30% of respondents reported that they had access to a radiometer,³ with this figure being little different from that reported in 1997 when it was reported that only 20% of dental practices had a means of checking the light intensity of their LCU.⁴ Recent results from the US-based Clinicians Report indicated that 21% of dentists never checked the output of their LCU.⁵