The Effect of Probiotics on Oral Health
Condition: Oral Disease
MeSH terms: Mouth Diseases
Study type: Interventional

Summary: 
      This will be a double-blind, randomized, placebo-controlled two-arm parallel groups study of
      the effect of oral probiotics containing Streptococcus salivarius K12 on oral biofilm,
      salivation rate, and secretory immunoglobulin A salivary level.

      The aim of the study is to assess the effect of oral probiotics containing Streptococcus
      salivarius K12 strain on oral biofilm, unstimulated salivary flow rate, and salivary
      secretory immunoglobulin A (sIgA) levels.
    

Detailed description: 
      Thirty consenting patients aged 20-24 years who will meet the inclusion criteria will be
      recruited in the study. At the preparatory phase patients will be recruited and randomized,
      their oral hygiene protocols will be standardized, researchers will be calibrated and
      trained. The main phase will include a double-blind, randomized, two-arm parallel group,
      placebo-controlled study of probiotics effects, and wash-out period. Patients will be
      randomly divided into 2 groups (group 1 - probiotics, group 2 - placebo). Clinical
      examination will be performed at baseline, after 4 weeks (probiotic/placebo intake) and 6
      weeks (wash-out), and will include the assessment of DMFT index, oral hygiene level (the
      Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI)), gingival inflammation (PMA
      index), salivation rate (unstimulated salivary flow), and salivary concentration of secretory
      immunoglobulins A.

      The study is estimated to complete enrollment within 4 weeks from study initiation; however,
      enrollment will remain open until the study goal is met. The duration of this study for each
      subject will be a maximum of eight (10) weeks: 4 weeks - preparatory period, 4 weeks -
      intervention period, and wash out period (2 weeks).

      Screening (First) visit

        -  Review the study with the subject and obtain written informed consent

        -  Assign the subject a unique screening/enrollment number

        -  Review and record medical history, and medication history to determine eligibility based
           on inclusion/exclusion criteria

        -  Record demographics (age, gender)

        -  Document vitals

        -  Document all current medications, including medications over-the-counter and herbal
           medications

        -  Perform physical examination

             -  Determine DMFT index

             -  Determine oral hygiene level (TQHPI)

        -  Provide training in standardised brushing techniques.

      The allocation concealment will be performed by the use of containers numbered by a "third
      party" (person, who will not participate in the study). The tablets in the bottles without
      titles will be placed in the containers. The tablets in different groups will look similar.
      The patient on enrollment will receive a container with tablets. Neither patients nor
      researchers will be aware of the type of a tablets received by each patient (double
      blinding).

      Baseline (Second) visit (4 weeks from the Screening visit) - all groups

      - Perform physical examination

        -  Determine DMFT index

        -  Determine oral hygiene level (TQHPI)

        -  Determine gingival tissue condition (PMA index)

        -  Determine unstimulated salivary flow rate

        -  Determine a concentration of secretory immunoglobulins A in saliva (ELISA)

      Third visit (4 weeks from the Baseline visit) - all groups

      - Perform physical examination

        -  Determine DMFT index

        -  Determine oral hygiene level (TQHPI))

        -  Determine gingival tissue condition (PMA index)

        -  Determine unstimulated salivary flow rate

        -  Determine a concentration of secretory immunoglobulins A in saliva (ELISA)

        -  Assess for adverse events

      Fourth visit (2 weeks from the Third visit) = Final Study Visit - all groups

        -  Perform physical examination • Determine DMFT index

           • Determine oral hygiene level (TQHPI))

           • Determine gingival tissue condition (PMA index)

             -  Determine unstimulated salivary flow rate

             -  Determine a concentration of secretory immunoglobulins A in saliva (ELISA)

             -  Assess for adverse events

      Early Termination visit

        -  Assess for adverse events

        -  Assess for complications following treatments

        -  Document all current medications, including medications over-the-counter and herbal
           medications

      Preparatory phase of the study Patient training Oral hygiene instructions will be given and
      the compliance with the recommendations will be controlled with weekly visits to the dental
      office. The participants will be familiarized with the assessment techniques and trial
      procedures Qualification and calibration of the observers The clinical examinations will be
      performed by two dentists who are the members of Therapeutic Dentistry Department, Sechenov
      University, Moscow, Russia. The examiners will be trained and calibrated to obtain an intra-
      and inter-examiner agreement of 90%, using Kappa statistics.

      Randomization Thirty people aged 20-24 years will be examined and randomly assigned to one of
      the study groups: Group 1 will use tablets containing probiotic (Streptococcus salivarius
      K12). Group 2 will use tablets containing placebo. The allocation concealment will be
      performed by the use of containers numbered by a "third party" (person, who will not
      participate in the study). The tablets in bottles without any titles will be placed in the
      containers. The tablets in both groups will look similar. The patient on enrolment will
      receive a container of tablets. Neither patients nor researchers will be aware of the type of
      tablets used.

      Treatment protocol The patients will use the prescribed tablets ("Bactoblis", registration
      number: AM.01.06.01.003.Е.000024.07.18; 20.07.18, MEDICO DOMUS, d.d.o. (18116, Nis, Serbia))
      for 4 weeks 1 tablet per day. The end of the treatment course will be followed by a two-week
      wash-out period. During the wash-out period, patients will have to stop taking their
      prescribed tablets. A wash-out period is necessary to assess the stability of the results
      achieved. Control examinations will be carried out in the following periods: 4 weeks and 6
      weeks.

      Physical examination

      The examination will include determination of:

      DMFT index, oral hygiene level (TQHPI), gingival tissue condition (PMA index), unstimulated
      salivary flow rate, and a concentration of secretory immunoglobulins A in saliva (ELISA).

      Data collection and reporting. Data will be collected at the following points: at baseline,
      and after 4 and 6 weeks of the study.

      Data from the study will be maintained for two (2) years after the date the investigation is
      completed, terminated or until the records are no longer required to support the protocol,
      whichever date is later. Patient records and data are eligible for inspection and/or copying
      by applicable regulatory authorities.

      Data handling and record keeping Data entry will be completed in the RedCap database (which
      will cover all the created CRFs). The data will be exported into CSV file format, which will
      then be used for data analysis. Only de-identified data will be used for data analysis. All
      hard copy documents will be shredded within five years after completion of the study upon
      Sponsor approval. Collected de-identified data will be sent to a biostatistician for
      statistical analysis.

      Adverse reactions. There is no expectation of any adverse outcomes or reactions due to a
      patient using probiotics or placebo. However, hypersensitivity reactions to some of the
      tablets' components are still possible. All participants will be given access to contact info
      of the investigators. Any adverse reactions should be reported immediately to the
      investigators.

      Reasons for Withdrawal or Termination

      The following is a list of possible reasons for study treatment discontinuation:

        -  Screening Failure

        -  Subject withdrawal of consent

        -  Subject is not compliant with study procedures

        -  Adverse Event that in the opinion of the Investigator would be in the best interest of
           the subject to discontinue study participation

        -  Protocol violation requiring discontinuation

        -  Lost to follow-up All subjects are free to withdraw from participation at any time, for
           any reason, specified or unspecified, and without prejudice.

      Statistical analysis plan All analyses will be performed using per-protocol population: all
      subjects will be analyzed who did not substantially deviate from the protocol as to be
      determined on a per-subject basis by the study principal investigator immediately before
      database lock.

      Data will be presented as means and standard deviations with 95% confidence intervals,
      medians and 25 and 75 percentiles, and percentages depending on the type of variables. The
      normality and sphericity of distribution of continuous variables will be assessed with
      Shapiro-Wilk and Leven's tests, respectively. If the assumptions of normality and sphericity
      are satisfied, repeated measures mixed ANOVA model will be performed followed by post-hoc
      Tukey test with adjustment for multiple comparisons. If the aforementioned assumptions are
      not satisfied, the differences between groups will be assessed using Mann-Witney U-test and
      the difference within the groups at different study timepoints will be assessed with Friedman
      test with post-hoc comparisons. The same non-parametric tests will be used for the analyses
      of categorical and ordinal variables. Fisher's exact test will be used to access the
      frequencies of categorical variables in the groups. Correlation between Salivation rate,
      salivary sIgA concentration, TQHPI, DMFT, Decay, and PMA will be assessed using Spearman
      correlation coefficient.

      All summary tables will be structured with a column for each timepoint and rows for each
      assessed outcome and will be annotated with the total population size relevant to that
      table/treatment, including any missing observations.
    

Intervention name(s): Bactoblis; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): dissolve the tablets in the mouth once a day for 4 weeks; dissolve the tablets in the mouth once a day for 4 weeks
Other intervention name(s): Probiotic: Streptococcus salivarius K12
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: probiotics; Streptococcus salivarius K12; dental biofilm; salivary secretory immunoglobulins A; unstimulated salivary flow rate