Effect of light activation on teeth whitening

Abstract Aim To evaluate the effect of a light-activated toothpaste on teeth whitening. Patients and methods Twenty-four intact anterior teeth recently extracted were selected. The shade of the selected teeth was measured by VITA Easyshade V and their shade ranged between (A3.5 -A4).Roots were separated at cemento-enamel junction, the crowns were embedded in acrylic blocks individually leaving the labial surfaces exposed. Each Sample was kept in artificial saliva individually. The samples were stained using black tea solution for 5 days. The solution was prepared by immersing two tea bags into boiling water for 5 min then filtered with a piece of gauze. The samples were randomly divided into two equal groups I and II (12 samples each), according to type of toothpaste to be used following the manufacturer’ recommendations; samples in group I treated with Blanx white shock toothpaste while those in group II treated with close up white now toothpaste. Brushing was done manually by one operator using a rotatory toothbrush machine (Oral-B Pro 1000) with pressure sensor. Medium bristle classic rotary toothbrush was used. According to the manufacturer instructions, the BlanX White Shock group, BlanX LED BITE was used directly on the specimen for 1 min after brushing The color of all samples was measured according to CIE (Lab) color system (Commission Internationale de L’Eclairage) by using a VITA Easyshade V spectrophotometer at baseline, after staining and at different time intervals; 3 and 6 weeks after brushing procedure. Results ANOVA test compared mean (ΔE) value at a level of significance ( P > 0.05) and revealed a statistical significant difference among baseline to after staining and 3, 6 after brushing the samples in both groups. In addition T test revealed a statistical significant difference between mean (ΔE) value of the samples in group I versus that recorded in group II after 3 weeks of brushing as well as after 6 weeks of brushing detecting a significant whitening effect on tooth color using (Blanx white shock toothpaste). Clinical significance Light-activated whitening toothpaste (Blanx white shock toothpaste) offer a significant whitening effect on tooth color compared to blue covarine containing whitening toothpaste (close up white now toothpaste).