Bovine colostrum is rich in antimicrobial substances and growth factors. The purpose of this open study was to examine and compare the interventory effects of daily use of bovine colostrum-containing oral hygiene products (CHP) on oral symptoms and findings in 20 patients with primary Sjogren's syndrome (pSS) and 20 age-matched patients with oral lichen planus (OLP). Objective oral measures and self-assessment of oral symptoms and general health were conducted before and after 90 days' use of CHP. The pSS patients had more systemic diseases, medication intake, oral dryness, poorer general health and lower salivary secretion than the OLP patients, who had the highest plaque index (PI) and the most mucosal soreness. Oral dryness and soreness were correlated to general health. In both patient groups. unstimulated whole saliva flow rate (UWS) had increased, PI and periodontal pocket depth (PPD) were reduced, and general health and oral dryness and soreness had improved after using CHP. A decrease in hyphae was found in candida smears from both groups and in blastospores in OLP smears. A reduction in the extension of the mucosal lesions was observed in 15 OLP patients. Results suggested beneficial effects of intervention with CHP on oral symptoms, general health, UWS, PI, PPD and candidal load in two patient groups--pSS and OLP--representing different oral symptomatology.