Wise Geek. "What is Prophylaxis?" http://www.wisegeek.com/what-is-prophylaxis.htm(accessed March 5, 2008). 

ADHA. "American Dental Hygienists' Association Position Paper on the Oral Prophylaxis," http://www.adha.org/profissues/prophylaxis.htm (accessed March 5, 2008).