EFFECTS OF A LACTOPEROXIDASE SYSTEM-CONTAINING TOOTHPASTE ON LEVELS OF HYPOTHIOCYANITE AND BACTERIA IN SALIVA

Lactoperoxidase (LPO)/H2O2/SCN--system-generated hypothiocyanite ions (OSCN-) and hypothlocyanous acid (HOSCN) are inhibitory against a numb er of oral bacteria, including mutans streptococci. A commercially ava ilable toothpaste (Biotene(R)) comprises the complete LPO system. Gene ration of HOSCN/OSCN- by Biotene was studied in vitro both in steriliz ed and nonsterilized saliva of 10 healthy subjects. The HOSCN/OSCN yie ld ranged from 100 to 300 muM with Biotene. while the salivary levels of HOSCN/OSCN before the addition of Biotene were 30.1+/-25.1 muM. Two in vivo trials were carried out. In the first study, resting saliva w as collected from 12 individuals before, immediately after, and 2, 5, 10 and 20 min after brushing with Biotene to evaluate the in vivo gene ration and decomposition of HOSCN/OSCN . In the second study, 26 healt hy individuals attended a 1-month crossover trial with Biotene and a c ontrol toothpaste, Vademecum(R) (no LPO system), both containing F- an d xylitol. The salivary counts of total streptococci, mutans streptoco cci (MS), lactobacilli and the total flora (TF), as well as the peroxi dase, thiocyanate ion and HOSCN/OSCN levels were determined before and after 2 and 4 weeks daily use of the toothpastes. Twice-a-day use of Biotene for 1 month resulted in an elevation of 'resting levels' of HO SCN/OSCN . No such effect was found with the control toothpaste. No si gnificant changes were found in the salivary levels of total streptoco cci, MS, lactobacilli or TF after 1-month use of either toothpaste. Th e results show the capability of the LPO-system-containing toothpaste to elevate the salivary levels of HOSCN/OSCN-, although no bactericida l effect was observed.