Antibacterial Effect of Probiotic Yogurt Compared to Xylitol

Study Overview
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Brief Summary
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This study will be conducted to evaluate the antibacterial effect of probiotic bacteria in yogurt in decreasing streptococcus mutans count in saliva and plaque, decreasing bacterial adherence and increasing salivary pH compared to xylitol-containing chewing gum after three months.

Detailed Description
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The subjects will be assigned randomly into two equal groups to receive either probiotic yogurt or xylitol-containing chewing gum for three months. The probiotic yogurt is (Activia; Danone, Egypt) containing Bifidobacterium (7x107 CFU/g). The subjects assigned to probiotic yogurt group will be instructed to eat 100 g of the provided yogurt 10 minutes after dinner and not to brush their teeth until one hour later. The subjects assigned to the xylitol-chewing gum group will be instructed to chew the provided gum three times daily for five minutes after each meal.

Official Title
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Comparison of Antibacterial Effect of Probiotic Yogurt Against Xylitol-containing Chewing Gum on Salivary Streptococcus Mutans Count, Bacterial Adherence and Salivary pH in Geriatric Patients: A Randomized Controlled Trial

Conditions
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Geriatric Patients

Intervention / Treatment
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* Dietary Supplement: Probiotic yogurt
* Dietary Supplement: xylitol chewing gum


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Above 50 years old. Have sufficient cognitive ability to understand consent procedures. Males or Females. Co-operative patients. High caries risk patients (≥105 CFU for streptococcus mutans count) Exclusion Criteria: Under antibiotic treatment Milk intolerant Consuming any other probiotic product Habitual consumers of xylitol products Use antibacterial mouthwash Lack of compliance Any systemic condition affecting salivary secretion

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: The subjects will be assigned randomly into two equal groups to receive either probiotic yogurt or xylitol-containing chewing gum for three months
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: xylitol chewing gum<br>Xylitol is widely used as an added sweetener in sugar-free products. It has been found to prevent dental caries through reducing dental plaque and limiting salivary streptococcus mutans counts and their produced levels of lactic acid | Dietary Supplement: xylitol chewing gum<br>* Xylitol is widely used as an added sweetener in sugar-free products. It has been found to prevent dental caries through reducing dental plaque and limiting salivary streptococcus mutans counts and their produced levels of lactic acid<br>|
| Experimental: probiotic yogurt<br>Probiotics are live microorganisms that confer oral health benefits by adhering to the oral mucosa and surface of teeth as a part of the biofilm thus preventing the adhesion, colonization, and proliferation of cariogenic bacteria inhibiting the formation of pathogenic plaque | Dietary Supplement: Probiotic yogurt<br>* Probiotics are found in different dairy products including yoghurt, that are known as carriers of probiotics. These products can be easily integrated in daily meals to reduce cariogenic streptococcus mutans bacteria in dental biofilm<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| streptococcus mutans count in saliva | The samples will be transported to the laboratory and cultured on selective media (dry Mitis Salivarius Agar with potassium tellurite medium and bacitracin) after serial dilutions. The plates will be incubated at 37ºC in 5-10% CO2 jar. then number of Colony Forming Units (CFU/ml) of Mutans Streptococci in saliva will be determined | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| streptococcus mutans count in plaque | The samples will then be dispersed and spread over the culture media plates (mitis salivarius-bacitracin Agar), and the plates will be incubated under aerobic conditions | 3 months | 
| salivary pH | All the saliva samples will be tested on the same day for salivary pH using digital pH meter. The equipment will be calibrated with distilled water to reach pH 7 every time before measuring each sample | 3 months | 
| bacterial adherence | After applying disclosing agent over teeth, standard photographic images of the maxillary and mandibular facial surfaces of teeth will be taken. Digital plaque image analysis will be used to analyze plaque coverage. Images will be converted into pixels to calculate the percentage of the tooth covered with plaque divided by the total tooth area (both tooth areas with and without plaque) as follows: plaque area coverage = [plaque pixels / (tooth pixels + plaque pixels)] × 100 The computer analysis results will be checked for consistency and accuracy by an expert in image analysis who is blinded to the assigned treatment | 3 months |