Acid Production in Dental Plaque After Exposure to Probiotic Bacteria

This study has been completed.
BioGaia AB
Calcin foundation, Denmark
Information provided by (Responsible Party):
Mette Kirstine Keller, University of Copenhagen Identifier:
First received: October 2, 2012
Last updated: October 3, 2012
Last verified: October 2012

The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA) production in vitro and in vivo.

Methods. subjects (n=18) were given lozenges with probiotic lactobacilli (L. reuteri DSM 17938 and ATCC PTA 5289) or placebo for two weeks in a double-blinded, randomized cross-over trial. The concentration of LA in supragingival plaque samples was determined at baseline and after 2 weeks. Salivary counts of mutans streptococci (MS) and lactobacilli were estimated with chair-side methods.

Condition Intervention
Dietary Supplement: Probiotic Lactobacilli reuteri
Dietary Supplement: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention

Further study details as provided by University of Copenhagen:

Primary Outcome Measures:
  • Acid production in plaque after exposure to probiotic bacteria [ Time Frame: 2 weeks ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Acid producton in plaque after in vitro exposure to probiotic bacteria [ Time Frame: 1 hour ] [ Designated as safety issue: Yes ]

Enrollment: 18
Study Start Date: December 2010
Study Completion Date: October 2011
Primary Completion Date: October 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: L. reuteri (DSM 17938 and ATCC PTA 5289; 1x108 CFU
2 tablets a day for 2 weeks
Dietary Supplement: Probiotic Lactobacilli reuteri
Placebo Comparator: Sugar pill
2 tablets a day for 2 weeks
Dietary Supplement: Placebo


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • moderate to high counts of salivary mutans streptococci (>104 CFU) as estimated with the Dentocult SM chair-side test,
  • no visible open caries lesions or periodontal disease,

Exclusion Criteria:

  • smokers,
  • ingestion of probiotic bacteria within the last two months,
  • ingestion of antibiotics within the last two months
  Contacts and Locations
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Please refer to this study by its identifier: NCT01700712

University of Copenhagen
Copenhagen, Denmark, 2100
Sponsors and Collaborators
University of Copenhagen
BioGaia AB
Calcin foundation, Denmark
Principal Investigator: Mette K Keller, PhD University of Copenhagen
  More Information

No publications provided by University of Copenhagen

Additional publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Mette Kirstine Keller, Reasearch Associate, University of Copenhagen Identifier: NCT01700712     History of Changes
Other Study ID Numbers: H-2-2010-112
Study First Received: October 2, 2012
Last Updated: October 3, 2012
Health Authority: Denmark:Danish Ethical Committee

Keywords provided by University of Copenhagen:
Caries, probiotic bacteria processed this record on November 27, 2015