Background: Probiotics are internationally defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. The main field of probiotics research concerns the gastrointestinal tract, but in the last few years, probiotics have also been researched for their effect on oral health. This article critically appraises a 2015 randomized controlled trial (RCT) that explores the benefits of probiotics in periodontal therapy.
Clinical question: To evaluate the effects of a probiotic tablet containing Streptococcus oralis KJ3, Streptococcus uberis KJ2, and Streptococcus rattus JH145 as adjunct to scaling and root planing (SRP) compared to SRP alone.
Summary of methods: A double-blind, placebo-controlled RCT was conducted with 48 patients with periodontitis. Specific inclusion and exclusion criteria were followed. The authors assessed full-mouth probing pocket depth (PPD), gingival recession (REC), and bleeding on probing (BOP) as outcomes, as well as plaque and gingival indices.
Critical appraisal: Based on current research standards, this was a well-conducted RCT. Assessment using the Critical Appraisal Skills Programme (CASP) critical appraisal tool indicated that most of the necessary qualities of a credible trial were present. However, both the fact that randomization was done with block randomization and the fact that no power analysis was done prior to the trial were considered weaknesses.
Practical implications: This study is statistically insignificant and shows no benefits of the use of probiotics clinically and microbiologically in treating adult patients with periodontitis.