Rubber dam is usually made of latex, with natural rubber as the raw material. The physical properties of latex make it very suitable for isolation of the tooth crown from the oral cavity, providing a tight seal. Excellent elasticity of latex is the key factor for easy and successful use of rubber dam.
Because of the increasing number of patients allergic to latex, however, alternative dam materials have to be available, too. Silicon based dams have been used for many years as an alternative to latex dams with allergic patients. The weakness with other materials is that they are less elastic and more expensive than latex.