In ancient times, when people were afflicted with various diseases and illnesses, they are often accused of evil spirits. It was believed that evil spirit invaded the body of a man, and then it caused the disease. If you could appease these spirits or to force them to leave, then the disease will be cured.
Many people around the world still maintain the same faith today, except that these evil spirits, currently defined. Dentists, scientists, doctors, and officials decided that pathogenic "evil spirits" now " real", in the form of microorganisms (viruses, bacteria and other). In common and generally accepted theory is that these viruses and bacteria are the main or the basic cause of the disease-including caries. This theory of disease, with the inscription of the germ theory has been put in our minds through the work of Louis Pasteur (1822-1895), famous for the invention of pasteurization.
Mr. Paster proposed a theory of the disease, which is now the basis of most forms of modern medicine. This theory of projects the idea that pathogenic bacteria
to exist outside the body, and that when our defenses are reduced bacteria can enter the body and cause disease.
Pasteur "science" has preserved the status quo, despite considerable evidence that bacteria are not to invade people, and that they develop and change, on the basis of their environment. The influence of Mr. Pasteur contribution to the development of the medical science has brought us to our present system of dental care, in which we try to cure tooth decay, killing evil invading forces-bacteria.