The Effects of Sodium Fluoride and Chlorhexidine Use on Salivary IL-6 and Matrix Metalloproteinase Levels in Children With Active Caries

Summary

This study aims to compare salivary IL-6, MMP-8, MMP-9, and TIMP-1 levels between healthy children and caries-active children, and to evaluate the effects of 5% sodium fluoride (NaF) varnish and 2% chlorhexidine (CHX) used in caries prevention on these biomarkers.

The study will be conducted at Alanya Alaaddin Keykubat University, Faculty of Dentistry, Department of Pediatric Dentistry. Informed consent will be obtained from children and their parents/guardians. Investigator calibration will be performed using Cohen's kappa method prior to data collection. Sample size was calculated assuming 80% power (1-β = 0.80), α = 0.05, and Cohen's d ≈ 0.8, resulting in 20 participants per group using G\*Power 3.1 software.

Study groups: Group A: 5% NaF varnish. Group B: 2% CHX + 5% NaF varnish. Group C: Standard oral hygiene education (negative control). Group D: Caries-free children (biological reference; baseline saliva sampling only).

Saliva samples will be collected at T0 (baseline), T1 (30 minutes post-application), and T2 (1 month). Unstimulated whole saliva will be collected, centrifuged at 5,000 g for 10 minutes at 4°C, and stored at -80°C. IL-6, MMP-8, MMP-9, and TIMP-1 levels will be measured using CE-marked/FDA-approved human saliva ELISA kits.

Conditions

• Dental Caries
• Dental Caries in Children

Interventions

OTHER

5% Sodium Fluoride Varnish

Teeth are gently air-dried for 30 seconds under isolation with cotton rolls and aspirator. Approximately 0.5 mL of 5% NaF varnish is applied to all tooth surfaces sequentially by quadrant starting from the upper jaw using an applicator tip and left in place for 1 minute. Parents are instructed to restrict water and hard food intake for 1 hour post-application. This is a routine preventive application; no off-label use is involved.

OTHER

2% Chlorhexidine Pre-Treatment + 5% NaF Varnish

Following isolation and air-drying, 2% chlorhexidine solution is applied to the lesion/tooth surfaces using an applicator tip and left in place for 30 seconds. Excess CHX is then absorbed. Precautions are taken to prevent ingestion. This pre-treatment is performed immediately prior to 5% NaF varnish application. This is a routine preventive application; no off-label use is involved.

BEHAVIORAL

Standard Oral Hygiene Education

Children and parents receive standardized oral hygiene education including instruction on twice-daily brushing with fluoride toothpaste, reduction of sugar intake frequency, and a brief parent information brochure. No professional topical agent is applied. Necessary treatment will be offered at the end of the study upon request (wait-list design).

Sponsors & Collaborators

• Alanya Alaaddin Keykubat University

  collaborator OTHER

• Gül Keskin

  lead OTHER

Principal Investigators

• GÜL KESKİN, DDS, PhD · Alanya Alaaddin Keykubat University

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

6 Years

Max Age

8 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-05-15

Primary Completion

2027-01-01

Completion

2027-06-30

Countries

• Turkey (Türkiye)

Study Locations