Corey A Felix1, Richard B T Price. 1. Department of Dental Clinical Sciences, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada.
Abstract
PURPOSE: To investigate how light intensity changes as the distance increases from the tip of the light guide. MATERIALS AND METHODS: Ten different curing light/light guide combinations were used. Light intensity was measured at 0, 3, 6, and 10 mm from the tip of the light guide with a radiometer. Measurements were repeated in five separate trials and the mean light intensity +/- standard deviation was calculated. The fiber density was measured at the entrance and exit of all ten light guides and the light dispersion patterns were recorded. RESULTS: Light intensity decreased as distance increased for all lights tested; however, the rate and extent of this decrease was not similar for all lights (p < 0.0001). Turbo light guides exhibited a more rapid decrease in intensity as the distance increased than standard light guides. At 10 mm, all the turbo light guides had lost over 80% of their intensity recorded at 0 mm. CONCLUSION: 1. The rate and extent of the decrease in intensity is not similar among curing lights (p < 0.0001). 2. It is not possible to predict light intensity at 10 mm from measurements made at 0 mm. 3. Curing light manufacturers should state intensity over clinically relevant distances (0 to 10 mm).
PURPOSE: To investigate how light intensity changes as the distance increases from the tip of the light guide. MATERIALS AND METHODS: Ten different curing light/light guide combinations were used. Light intensity was measured at 0, 3, 6, and 10 mm from the tip of the light guide with a radiometer. Measurements were repeated in five separate trials and the mean light intensity +/- standard deviation was calculated. The fiber density was measured at the entrance and exit of all ten light guides and the light dispersion patterns were recorded. RESULTS: Light intensity decreased as distance increased for all lights tested; however, the rate and extent of this decrease was not similar for all lights (p < 0.0001). Turbo light guides exhibited a more rapid decrease in intensity as the distance increased than standard light guides. At 10 mm, all the turbo light guides had lost over 80% of their intensity recorded at 0 mm. CONCLUSION: 1. The rate and extent of the decrease in intensity is not similar among curing lights (p < 0.0001). 2. It is not possible to predict light intensity at 10 mm from measurements made at 0 mm. 3. Curing light manufacturers should state intensity over clinically relevant distances (0 to 10 mm).
Authors: M Tielemans; Ph Compere; S O Geerts; M Lamy; M Limme; R J G De Moor; K I M Delmé; M F Bertrand; E Rompen; S Nammour Journal: Lasers Med Sci Date: 2007-11-24 Impact factor: 3.161
Authors: Richard Bengt Price; Daniel Labrie; Sonya Kazmi; John Fahey; Christopher M Felix Journal: Clin Oral Investig Date: 2011-05-12 Impact factor: 3.573