The effectiveness of light-polymerization instructions to Toronto dentists

Objectives: To determine the effectiveness of light-polymerization instructions on dentists in private dental offices in the Greater Toronto Area.
Methods: Dental offices were recruited. Dental practitioners (n=113) were asked to use their office's LED Light Polymerization Units (LPUs) and their common technique three times and simulate light-polymerization to anterior and posterior sensors on the MARC® Patient Simulator (PS) (BlueLight Analytics, Halifax, Canada). Practitioners then received instructions on how to use their own LPU which included mandatory use of protective-glasses and two-hand light-polymerization technique for better LPU control. Participants were retested using the same protocol and LED-LPUs that they used before. Data were statistically analyzed using paired-samples t-tests and mixed ANOVA with a pre-set alpha of .05.
Results: After the dentists received instructions, there was a significant increase in the amount of energy they delivered to both the anterior (t ₍₁₁₂₎ = -10.26, p <.001, 95%CI for MD: -3.14; -2.13) and the posterior sensor on the MARC-PS (t ₍₁₁₂₎ = -12.26, p <.001, 95%CI for MD: -3.17; -2.29). Energy delivery was more consistent after the dentists had received the instructions (Wilk's Lambda=0.91, F (1,110) =10.42, p=.002).
Conclusions: After instructions, the dentists increased on average the amount of light energy delivered to the anterior sensor by 22.6% and the posterior sensor by 30.4%. The consistency of light-energy delivery was improved by 25.9% on average. Clinical significance: When dentists received instructions on two-hand light-polymerization technique using their own LPUs, they were able to substantially improve (on average 26.5%) the amount of light energy delivered to simulated restorations.