Oral-Spray Bacillus Spore Probiotics for Periodontal Disease Prevention and Supprotive Treatment in the Elderly

Periodontal diseases are strongly associated with dysbiosis of the oral microbiome within the biofilm. Key pathogens, including Streptococcus mutans, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis, contribute to caries progression and periodontal inflammation. Given the limitations of antibiotic use and their potential side effects, probiotics represent a promising biological approach to restore microbial balance and support oral health. In this study, researchers propose that direct application of probiotic spray into the oral cavity is safe and effective in alleviating typical symptoms of periodontal disease, particularly by reducing pathogenic bacterial density. The objective of this study is to evaluate the safety and efficacy of a oral-spray Bacillus spore probiotics (LiveSpo Smile CARE), containing Bacillus subtilis ANA48 and Bacillus clausii ANA39 at a concentration of ≥ 1 billion CFU/mL x 20 mL formulation, for the prevention and supportive treatment of periodontal disease. Study Design: * Sample Size: 90 participants * Study Location: an elderly care center in Hanoi, Vietnam Intervention Description: A total of 90 eligible participants will be randomly assigned to two groups (n = 45 per group). * The Placebo Group will receive 0.9% NaCl physiological saline, spray twice daily (afternoon and evening), with two sprays per application at three sites (both dental arches and the front teeth), totaling six sprays per use, for four consecutive weeks. * The Smile Care Group will receive an oral-spray probiotics containing ≥ 1 billion CFU/mL × 20 mL of Bacillus subtilis and Bacillus clausii (LiveSpo Smile CARE), administered with the same dosage and frequency as the placebo group. All participants will receive blinded, coded spray bottles to ensure objectivity. Both groups will be instructed to use the same standardized toothpaste during the study period. Caregivers will monitor the health status of participants and record relevant information in their medical records. During the study, caregivers will be instructed not to provide any additional probiotic oral care products or the solution contains similar components. Study Duration: 12-18 months.