Instant tooth whitening from a silica toothpaste containing blue covarine.

Objective: To measure the instant whitening effect delivered immediately after brushing with a novel silica whitening toothpaste containing blue covarine.

Methods: A controlled, single blind, cross-over study was performed to compare the tooth colour measured in a group of subjects at baseline and immediately after brushing with a silica whitening toothpaste containing blue covarine versus a clear gel negative control toothpaste. Measurements of tooth colour were made using a mobile non-contact camera-based digital imaging system and expressed as CIELAB and WIO whiteness index.