Study design: It is a Randomized Controlled clinical Trial.

Study setting: Study will be carried out in the Department of Pediatric and Preventive Dentistry, a residential school for special health care needs children and Department of Microbiology after gaining clearance from institutional ethical committee.

Study population: Children of age group of 7-13 yrs in a residential school for handicapped children.

Sample size: The sample size is calculated using Openepi software (v3.0) at 95% confidence interval and 80% power in reference the study conducted by Sengupta et al.

 The formula for the same is:

N = (σ1 ² + σ2 ² / κ) (Z1 – α /2 + Z1 – β) / Δ²

The notation for the formulae:

N = sample size

σ 1 = standard deviation of Group 1

 Ïƒ 2 = standard deviation of Group 2

 Î” = difference in group means

 Îš = ratio = 1

 Z1 – α /2 = two-sided Z value (ex. Z=1.96 for 95% confidence interval).

 Z1 – β = power

 N= (12.32 x 12.32) + (12.24 x 12.2) (1.96 +0 .84)² / (-10.17 x -10.17)

  = 23

The calculated sample size is 23 samples per group, whereas sample size selected is 30 for the study. (n=30)

Sampling technique and blinding:

Patients will randomly be assigned into 3 groups using AI generated random allocation table with no crossover within and among groups and present size of groups.

Method of selection of study subject:

INCLUSION CRITERIA:

1.     Special health care needs children in the age group of 7 to 13 years (Both males and Females).

2.     Participants who had not received any antibiotic agent or professional fluoride therapy within the last month.

3.     Children with active carious lesions.

4.     Children willing to participate in the study.

EXCLUSION CRITERIA:

1.     Individuals with habitual use of dairy probiotics or xylitol chewing gums.

2.     Those who have severe debilitating medical condition.

3.     Children not willing to / able to cooperate.

Study material:

o  Commercially available conventional toothpaste for children.

o  Commercially available xylitol toothpaste.

o  Commercially available xylitol-probiotic toothpaste.

Study armamentarium:

o  Sterile plastic cups

o  Glass tubes

o  Paraffin wax chewing gums

o  Transport media

o  Petri dish

o  Selective culture medium

o  Sterile gloves

o  Face mask

 Study groups:

Experimental design:

Collection of samples:

·       Procedure for salivary sample collection:

o   First sample will be collected at the start of the study (Pre samples) and

o   Post samples will be collected after the study period of 6 weeks.

o   Samples will be collected using a sterile plastic cup for 5 min during paraffin-wax chewing.

o   Participants will be instructed not to eat or drink for 2 hrs before collection of saliva    samples.

o   Participants will be instructed to brush their teeth twice a day using their allocated toothpaste and modified bass technique during study period.

o    Participants were restrained from using any other toothpaste or oral product.

·       Processing and Evaluation:

o   The pre- and post-intervention samples will be immediately transferred to the department of microbiology, where processing will be done within 2 hrs of collection of the sample.

o   Samples will be incubated for 24 to 48 hrs at 37°c and inoculated on selective media for bacterial identification of streptococcus mutans and lactobacilli.

o   Pre- and post-intervention samples identification and quantification of streptococcus mutans and lactobacilli growth will be done.

Statistical analysis:

•        Data will be arranged in tables and graphs in Microsoft excel

•       Descriptive statistics will be performed in terms of mean, standard deviation, frequency and percentage.

•       Unpaired t test will be applied to compare between the groups respectively.

•       Statistical significance will be calculated at p<0.05.