This study aims to evaluate whether a short, 14-day administration of chewable tablets containing heat-inactivated Lactobacillus salivarius HM-6 Paradens can influence selected salivary parameters related to oral health in preschool children. The probiotic preparation used in the intervention group is a commercially available product (Acidolac Dentifix Kids, Polpharma, Poland). Each tablet contains 10 mg of heat-inactivated Lactobacillus salivarius HM-6 Paradens, along with isomalt, sucralose, natural strawberry flavor, magnesium stearate, and 200 mg of xylitol.
Children in the intervention group receive two chewable tablets per day for 14 consecutive days: one after breakfast and one at bedtime. Each tablet is taken after toothbrushing. After chewing the tablet, children are instructed not to eat or drink for two hours to ensure consistent exposure to the preparation. Adherence is monitored by counting unused tablets returned by caregivers. Missing no more than two tablets per week is considered acceptable adherence, while more frequent missed doses are classified as questionable compliance. Caregivers are asked to report any illnesses, adverse events, or circumstances that may influence the child's participation.
Before the intervention, each child undergoes a dental examination. The presence of early childhood caries (ECC) is recorded, and caries severity is assessed using the International Caries Detection and Assessment System II (ICDAS II). Baseline ICDAS II scores are used to analyze whether initial caries severity affects changes in salivary parameters.
Saliva samples are collected at two time points: before the intervention and after 14 days of follow-up. Collections take place between 8:00 AM and 10:00 AM. Caregivers ensure that children do not eat or drink (except water) for at least 60 minutes before sampling and do not perform oral hygiene beforehand. Unstimulated whole saliva is collected into sterile polypropylene tubes, refrigerated immediately, centrifuged to remove debris, aliquoted, and stored at -80°C. Stimulated saliva is collected using a Salivette kit (Sarstedt, Germany). Children chew a sterile swab for 2-3 minutes, after which the sample is centrifuged, aliquoted, and stored at -80°C. All samples undergo one freeze-thaw cycle before analysis.
Salivary pH is measured at baseline and after the intervention under standardized preanalytical conditions. Results are reported as dimensionless pH values.
The study procedures are non-invasive and well tolerated by children. The goal is to determine whether short-term exposure to an inactivated probiotic preparation can beneficially influence the oral environment and salivary biomarkers in preschool-aged children.