2Nathoo S, Petrone ME, DeVizio W, et al. A six-week clinical study to compare the stain removal efficacy of three dentifrices. J Clin Dent, 2002,13:91-94.
3Singh S, Mankodi S, Chaknis P, et al. The clinical efficacy of a new tooth whitening dentifrice formulation: a six-month study in adults. J Clin Dent, 2002,13:86-90.
4Ozcan M, Kulak Y, Kazazoglu E. The efficacy of two prototype chewing gums for the removal of extrinsic tooth stain. Int Dent J, 2003,53:62-66.
5García-Godoy F, Ellacuria J. Effectiveness of Sonicare power toothbrush to remove chlorhexidine stains. Am J Dent, 2002,15:290-292.
6Lin HC, Wong MCM, Wang ZJ, et al. Oral health knowledge, attitudes, and practices of Chinese adults. J Dent Res, 2001,80:1466-1470.
7Lobene RR. Effect of dentifrices on tooth stains with controlled brushing. J Am Dent Assoc,1968,77:849-855.