For prophylactic antisepsis of the oral cavity 12 antiseptic solutions and 4 antiseptically acting tablets were examined in vivo. A total of 720 samples were evaluated after indirect contact sampling and 80 after direct contact sampling. After the evaluation of the in vivo findings the following antiseptic agents can be recommended for prophylactic antisepsis of the oral cavity in stomatological practice: the 0.2% chlorhexidine solution, the 0.1% aqueous solution of Tosyl-chloramid-Sodium, and Sulfachin.