Effect of Probiotic on the Plaque pH. A Randomized Double Blind Interventional Study
Condition: Plaque Ph Lowering After Use of Probiotics; Caries; Gingivitis
MeSH terms: Gingivitis
Study type: Interventional
Phase: Phase 4

Summary: 
      The aim of the present research protocol was to evaluate the effect of probiotics daily used,
      on the plaque acidogenicity of children. The null hypothesis was that the plaque
      acidogenicity would remain unchanged and not associate with the use of probiotics. Moreover,
      the in situ study will be carried out to investigate the plaque formation as biofilm in
      demineralised enamel specimens following the regular consumption of a probiotic product
      compared to a control group. Metabolic of the biofilm formed on of the enamel specimens
      resulting from the consumption will be evaluated over a period of 8 weeks.
    

Detailed description: 
      Prior to the start of the study, demographic, ethnic and prognostic data will be collected
      (screening phase). A medical history will be taken, with documentation of previous and
      concomitant treatment and a clinical examination of the oral cavity (dental status, oral
      mucosa) will be performed by the investigator. If the test subject meets all the inclusion
      criteria without fulfilling any of the exclusion criteria, he/she will be enrolled in the
      clinical trial and given a test subject identification number.

      All test subjects will receive a patient diary in the screening phase.

      Washout phase I (1 week):

      The test subjects will use only the fluoride-containing toothpaste provided by the sponsor
      for daily oral hygiene. A soft toothbrush will likewise be provided.

      The test subjects will also receive a patient diary which will inform them that during the
      treatment phase they may not use any fluoride containing oral hygiene products (tooth-paste,
      mouthwashes, gels etc.) other than the study tooth-paste, drink any fluoride-containing
      mineral water or black tea, or eat any fish meals.

      Treatment phase I (6 weeks):

      Following washout phase I, the test subjects start the first treatment phase. Plaque pH
      measurements at 1 week.

      All subjects are instructed about oral hygiene and about the consumption of the study
      product.

      Treatment phase II (1 week after):

      The test subjects will use only the fluoride-containing toothpaste provided by the sponsor
      for daily oral hygiene. A soft toothbrush will likewise be provided. Plaque pH measurements.

        1. MATERIALS AND METHODS 1.1 Clinical parameters DMFT index, gingival index

           1.2 Investigation of saliva factors Saliva factors pH and flow rate will be measured
           during the screening phase on three days, each time in the morning. The mean of the
           three measurements will be calculated.

           The Dentobuff® test kit (Vivadent, Liechtenstein) will be used.

           1.3 Teeth brushing technique Test subjects are required to clean their teeth three times
           a day with the fluoride-containing toothpaste and a soft toothbrush. During that time, a
           fresh, damp gauze (soaked in water) will be placed in the container each day in order to
           provide a moist atmosphere for the appliances. The specimens should not be allowed to
           dry out.

           The enamel specimens themselves are likewise carefully cleaned with the soft toothbrush
           except the last day of every period.

           1.4 Randomization Using a computer program (Excel 2003 for Mac OsX), the randomization
           will carried out on an individual basis.

           1.5 Application of the study product The subjects are not allowed to chew the lozenges.
           They are allowed to swallow the lozenges.

           1.6 Plaque-pH evaluation At the end of each phase plaque acidogenicity will be assessed
           using the MicroTouch technique after a previous sucrose challenge. Evaluations of pH
           will be carried out at on each specimen. The pH will be measured in quintuplicate at 6
           different time points: at baseline (before sucrose rinse) and 2, 5, 10, 20 and 30 min
           after a 1-min rinse with 10 ml 10% sucrose, using active movements.

           An iridium touch microelectrode (diameter 0.1 mm; Beetrode® NMPH-1, World Precision
           Instruments, Sarasota, Fla., USA, with a porous glass reference electrode (MERE 1, World
           Precision Instruments) will be used. A salt bridge will be created in a KCl (3 M)
           solution between the reference electrode and a finger of the subject. Before each
           session of pH evaluation, the electrode will be calibrated using buffer solution at pH
           7.00 and 4.00.

        2. STATISTICAL METHODS AND DETERMINATION OF SAMPLE SIZE 2.1 Planned Analysis Descriptive
           summary statistics will be computed for all parameters documented in the case report
           form (CRF).

      Quantitative parameters will be described by seven-point scales with mean, standard
      deviation, median, quartiles, minimum and maximum. Absolute and relative frequencies will be
      given for qualitative variables. All descriptions will be done separately for treatment
      groups and visits.

      The full statistical analysis including details such as methods of dealing with outliers,
      missing values, data under prohibited concomitant medication, prohibited nutrition or other
      possible irregularities will be fixed in a more detailed statistical analysis plan, which
      will be updated during a blind review of the data before applying the randomisation code to
      the data for the final analysis.

      In order to ensure that the database accurately reflects the data reported in the CRF, a
      double data entry procedure (data entered by different staff in two separate data files) will
      be used. In addition to an electronic comparison of these two data files a validation of the
      data will check ranges, consistency and plausibility. Unclear data will undergo a data
      cleaning process ("queries"). Any changes applied to data in the database during data
      cleaning will be recorded in a special log file. The database will be frozen on completion of
      data cleaning.

      Appropriate validated software (e.g. SAS, SPSS) will be used for the data processing and
      statistical evaluation.

      Confirmative statistical testing For confirmative statistical testing an analysis of variance
      (ANOVA) model will be used as a global test, including the treatment sequences as "between
      subject factors" and the treatment conditions as "within subject factors".

      The full analysis will be described in detail in a specific statistical analysis plan before
      unblinding the data.

      Adjustment of type I error due to multiple testing is not necessary due to a prior ordering
      of the hypotheses. Hypothesis testing has to be stopped if a null-hypothesis may not be
      rejected at the 5% error level α. This procedure maintains a constant global level of α = 5%.
    

Intervention name(s): consumption of lozenges
Intervention type(s): Dietary Supplement
Intervention description(s): Each subject two lozenges a day for 6 weeks
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Prevention
Keywords: Lactobacillus Brevis CD2; schoolchildren; dental caries; Gingivatis