Professional dental cleanings remove tartar deposits on the teeth but cannot stop the regrowth of acid-loving bacteria. Nor will a cleaning strengthen or protect teeth. After a deep scaling by a hygienist, oral bacteria are dislodged and flow into the blood stream, challenging the immune system. The body responds to this perceived attack by releasing white blood cells to combat the invading microbes, and one of the results is systemic inflammation. Also, many harmful bacteria stay in the saliva and will reestablish themselves on the teeth and in the blood stream.