The Probiotic for Oral Health (PRO Health) Study

Not Applicable

Completed

• Conditions: Oral Microbiome
• Interventions: Dietary Supplement: Streptococcus-Containing Probiotic Supplement; Dietary Supplement: Placebo-Control Supplement

• Registration Number: NCT03748017
• Lead Sponsor: University of California, Davis

Brief Summary

The PRO Health Study is a single-center, prospective, double-blind, randomized, placebo-controlled trial of streptococcus-containing supplementation in healthy adults.

Detailed Description

Upon enrollment, healthy adults will enter a 1-week lead-in period which serves as an opportunity to collect baseline saliva samples and complete daily logs. Subjects that meet eligibility criteria on Day 7 will be randomized into 1 of 2 groups, receiving either a placebo-control or a streptococcus-containing probiotic supplement. Supplementation will begin on Day 8 and will continue for a total of 14 consecutive days. Participants will be observed for an additional 2 weeks following cessation of supplementation. The total duration of the study will be approximately 5 weeks. Saliva samples will be collected on 7 occasions and participants will be asked to complete questionnaires and daily diet and health logs throughout the course of the study.

Study Timeline

• Study Start: 2018-09-04
• Study First Submitted: 2018-10-22
• Study First Submitted QC: 2018-11-16
• Study First Posted: 2018-11-20
• Primary Completion: 2019-03-10
• Study Completion: 2021-10-01
• Status Verified: 2023-11
• Last Update Submitted: 2023-11-27
• Last Update Posted: 2023-11-28

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 26

Inclusion Criteria

• Healthy adults;
• Age 21-45 years of age;
• BMI between 18-30;
• No history of infectious disease; heart, metabolic, autoimmune endocrine, liver, or kidney diseases; GI related conditions such as malabsorption disease, Crohn's disease, colitis, inflammatory bowel disease; Type 1 or 2 diabetes mellitus, any type of cancer, heart disease;
• Practices good oral hygiene according to the American Dental Association with brushing teeth between 1-2 times per day;
• Willingness to only use the study toothpaste to brush or clean teeth and refrain from using any other oral-care products such as other toothpaste, mouthwash, rinses and breath-sprays during the five-week study period;
• Willingness to limit consumption of raw onions or garlic and fermented foods such as sauerkraut, pickles, miso, and kimchi during the five-week study period;
• Non-alcohol consumers or those who consume alcohol in moderation defined as having up to 1 drink per day for women and up to 2 drinks per day for men;
• Willingness to avoid binge drinking during the study period defined by the Centers for Disease Control and Prevention as: This pattern of drinking usually corresponds to 5 or more drinks on a single occasion for men or 4 or more drinks on a single occasion for women, generally within about 2 hours;
• Willingness to refrain from drinking any alcohol within 24 hours of each saliva sample collection;
• Willingness to refrain from using illicit drugs during the five-week study;
• Willingness to refrain from using tobacco (smoking or chewing) or smoking marijuana during the five-week study period;
• Willingness to refrain from intake of probiotics, kombucha, or yogurt during the five-week study period;
• Willingness to refrain from consuming more than 1 package of sugary candy and from chewing more than 1 package of chewing gum during the five-week study period;
• Willingness to refrain from having any non-emergency, elective oral surgeries, dental procedures or dental teeth cleanings during the five-week study period.

Exclusion Criteria

• Currently pregnant or plans to become pregnant several weeks prior to enrollment and during the five-week study period;
• History of periodontal disease, or gingivitis;
• Dental trauma or injury to the teeth and/or periodontium (gums, periodontal ligament, alveolar bone), and nearby soft tissues such as the lips, tongue within the past 4 weeks;
• Any oral surgery or intensive procedures made to the oral cavity (such as fillings, wisdom tooth extraction, root canal, dental implants, etc.) within the past 4 weeks;
• Routine dental cleaning within the past 4 weeks;
• Use of probiotics, kombucha, or yogurt/kefir within the past 7 days of enrollment;
• Use of probiotics containing S. salivarius within the past 8 weeks of enrollment;
• Use of oral or IV antibiotics within the past 8 weeks of enrollment;
• Consumption of more than one package of sugary candy (hard candy, gummy candy, mints, etc.) per day;
• Use of more than one package of chewing gum (sugary or sugarless) per day;
• Use of mouthwashes, mouth-rinses or breath-sprays more than three times per day;
• Current tobacco (smoking or chewing) or E-cigarette users or individuals who quit using less than one year before enrolling in the study;
• Frequent marijuana smoking or vaping, or use of other illicit drugs (must be no more than 12 times within the past year and no more than once per month);
• Marijuana smoking or vaping or use of other illicit drugs within the past 4 weeks;
• Excessive alcohol drinkers: For men, heavy drinking is typically defined as consuming 15 drinks or more per week. For women, heavy drinking is typically defined as consuming 8 drinks or more per week;
• Individuals who live within the same household or who are in intimate relationships with current or past study participants (to avoid horizontal transfer of the oral microbiome);
• Anyone the investigator feels isn't an applicable participant.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Streptococcus-Containing Probiotic Supplement	Streptococcus-Containing Probiotic Supplement	12 participants will receive a powdered probiotic containing 7.77 billion colony-forming units (CFU) of L. acidophilus, 8.25 billion CFU of B. lactis, and 2 billion CFU of S. salivarius bacteriocin-like inhibitory substance (BLIS) K12 per daily oral feeding.
Placebo-Control Supplement	Placebo-Control Supplement	12 participants will receive a placebo-control supplement per daily oral feeding.

Primary Outcome Measures

Name	Time	Method
Oral Streptococci levels in adults at 22 days - difference between S. Salivarius and placebo	22 Days	The difference in levels of oral Streptococci between a streptococcus-containing probiotic supplement (e.g., S. salivarius K12) and placebo-control supplement on Day 22.

Secondary Outcome Measures

Name	Time	Method
Oral microbiome	Change from baseline, days 10, 14, 22, 28, 36	The difference in the salivary microbiome before, during and after intake of a streptococcus-containing probiotic supplement (e.g., S. salivarius K12) and placebo-control supplement.
Changes in stool firmness	Change from baseline, days 10, 14, 22, 28, 36	The relationship between supplementation and number of stools per day, rated using a continuous scale of 1 to 10 (1 = extremely watery, almost entirely liquid to 10 = extremely hard, difficult to pass).
Changes in stool consistency	Change from baseline, days 10, 14, 22, 28, 36	The relationship between supplementation and number of stools per day, rated using the Bristol Stool Scale.
Number of stools per day	Change from baseline, days 10, 14, 22, 28, 36	The relationship between supplementation and number of stools per day.
Oral Streptococcus levels	Change from baseline, days 10, 14, 22, 28, 36	The difference in levels of Streptococci upon intake of a streptococcus-containing probiotic supplement (e.g., S. salivarius K12) before, during and after the intervention compared with a placebo-control supplement.

Trial Locations

Locations (1)

University of California, Davis; 🇺🇸 Davis, California, United States