The present research aims to evaluate the efficiency of kefir mouthwash in enhancing oral health status by employing an in vivo experimental approach. Specifically, the study will assess how kefir mouthwash influences key oral health indicators, including gingival inflammation, plaque development, oral hygiene status, and halitosis. The study will be conducted over a 28-day period, with follow-up assessments every 14 days. The study will include systemically healthy adults with moderate gingivitis. Clinical parameters such as the Gingival Index (GI), Plaque Index (PI), and Simplified Oral Hygiene Index (OHI-S) will be measured, along with inflammatory biomarkers, including Interleukin-1β (IL-1β) and Interleukin-10 (IL-10). Halitosis will be evaluated using a Hali meter device. All of these will be measured at base line and day 14 and day 28 end of the study. Chlorhexidine 0.12% will be used as a comparative control to evaluate the efficacy of kefir mouthwash in improving oral health. This research intends to provide scientific evidence supporting the use of kefir as a probiotic-based mouthwash, offering a natural alternative to chemical mouthwashes and potentially reducing the negative consequences commonly associated with their use.

Due to their antibacterial qualities, conventional oral hygiene products such as chlorhexidine mouthwashes have been extensively used. However, their prolonged usage is often linked to negative effects, including taste changes, tooth discoloration, and mucosal discomfort. In response, natural and probiotic-based substitutes that provide efficient antibacterial activity with minimal adverse effects have attracted increasing attention. One such alternative gaining interest is kefir, a fermented milk product rich in antimicrobial peptides, probiotics, and bioactive components, which will be used in this study to assess the impact of kefir mouthwash on oral health.

The study will involve 60 systemically healthy adults aged 18 to 28 years, with moderate gingivitis. Participants will be selected from dental students at Bilad Al-Rafi Dain University and trained dentists from a specialist dental center in Diyala city. A triple-blind design will be used to eliminate bias, where the participants, the researchers administering the intervention, and the data analysts will all be blind to group assignments. Participants will be randomly assigned to one of two groups: the chlorhexidine 0.12% Bio Fresh group (Scirto Co for Bio Fresh LIC, P.O. Box 87218, Dubai, U.A.E.) or the kefir group (Yogourmet, France).

The research will span 28 days, with three data collection periods: baseline (Day 0), Week 2 (Day 14), and Week 4 (Day 28). Participants will use either kefir mouthwash or chlorhexidine 0.12% Bio Fresh mouthwash twice daily for one minute, 30 minutes after brushing their teeth, while refraining from eating or drinking for one hour after use. Both groups will receive mouthwashes in bottles that are identical in color and shape, labeled with random codes (A or B) to maintain blinding.

The chlorhexidine 0.12% Bio Fresh mouthwash will contain 0.12% Chlorhexidine Digluconate, purified water, sodium saccharin, Cremophor, flavoring, and glycerin, while the kefir mouthwash will be made using kefir powder containing live probiotic strains and active bacterial and yeast cultures, including Lactococcus lactis, Lactococcus cremoris, Lactococcus diacetylactis, Lactobacillus acidophilus, Saccharomyces cerevisiae, Kluyveromyces lactis, and maltodextrin, along with 3% fat milk.

The effectiveness of the mouthwashes will be assessed by evaluating the Plaque Index, Gingival Index, Simplified Oral Hygiene Index, and inflammatory cytokines (IL-1β and IL-10) at baseline, 14 days, and 28 days. Saliva samples will be collected at each follow-up to analyze the inflammatory response, and halitosis will be measured using the Hali Meter device. Participants will be monitored for compliance via daily tracking logs, electronic reminders through a WhatsApp group, and follow-up visits. Non-compliance or failure to adhere to the protocol will result in exclusion from the study.

Inclusion Criteria:

• Age range 18-28 years.
• Systemically healthy people without a history of chronic illness.
• Those suffering with moderate gingivitis.
• Not using any antibiotics over three months

Exclusion Criteria:

• History of systemic diseases.
• Pregnant, lactating females.
• History of antibiotic therapy in the past 3 months.
• History of oral prophylaxis within the last 6 months prior to the study as this can confound the results, making it difficult to determine the real effect of the mouthwash.
• Subjects with mouth breathing habits.
• Subjects with orthodontic and prosthodontic appliances.
• Subjects with deleterious habits such as smoking, because it may affect oral health status, causing periodontal disease, altered oral microbiota, and impaired healing. This can confound the study results, making it difficult to observe the mouthwash effect .
• Failure to follow the prescription regimen.
• Failure to follow the research protocol.

Upon verifying a diagnosis of moderate gingivitis, sixty individuals will be randomly allocated into two parallel groups using the Research Randomizer program (v. 2.0, https://www.randomizer.org),to mitigate bias.

This procedure will be managed by a practiced dentist who is not participating in the trial and is securely maintain under his exclusive control.

Both mouthwashes will be contained in bottles of similar color and form, labeled with codes (A, B) to ensure experimental blinding. This blinding technique guaranteed that neither the participants nor the examiner and no data analyses aware of the specific mouthwash included in each bottle.