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

NCT07609797 | Recruiting

• 1 other identifier: 2025-KAEK-44
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief 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

Keywords

Dental caries; Matrix metalloproteinase; Interleukin-6; Sodium fluoride; Chlorhexidine

Outcome Measures

Primary Outcomes (4)

• Change in Salivary MMP-8 Levels

  Change in salivary matrix metalloproteinase-8 (MMP-8) concentration measured by ELISA from baseline (T0) to post-application (T1) and 1 month post-intervention (T2) , and comparison between caries-active and caries-free groups at baseline. Unstimulated whole saliva samples will be analyzed using CE-marked/FDA-approved human saliva ELISA kits. Results expressed as ng/mL.

  Baseline (T0), 30 minutes post-application (T1), 1 month post-intervention (T2)

• Change in Salivary IL-6 Levels

  Change in salivary interleukin-6 (IL-6) concentration measured by ELISA from baseline (T0) to post-application (T1) and 1 month post-intervention (T2) , and comparison between caries-active and caries-free groups at baseline. Unstimulated whole saliva samples will be collected, centrifuged at 5,000 g for 10 minutes at 4°C, stored at -80°C, and analyzed using CE-marked/FDA-approved human saliva ELISA kits. Results expressed as pg/mL.

  Baseline (T0), 30 minutes post-application (T1), 1 month post-intervention (T2)

• Change in Salivary MMP-9 Levels

  Change in salivary matrix metalloproteinase-9 (MMP-9) concentration measured by ELISA from baseline (T0) to post-application (T1) and 1 month post-intervention (T2), and comparison between caries-active and caries-free groups at baseline. Unstimulated whole saliva samples will be analyzed using CE-marked/FDA-approved human saliva ELISA kits. Results expressed as ng/mL.

  Baseline (T0), 30 minutes post-application (T1), 1 month post-intervention (T2)

• Change in Salivary TIMP-1 Levels

  Change in salivary tissue inhibitor of metalloproteinase-1 (TIMP-1) concentration measured by ELISA from baseline (T0) to post-application (T1) and 1 month post-intervention (T2), and comparison between caries-active and caries-free groups at baseline. Unstimulated whole saliva samples will be analyzed using CE-marked/FDA-approved human saliva ELISA kits. Results expressed as ng/mL.

  Baseline (T0), 30 minutes post-application (T1), 1 month post-intervention (T2)

Study Arms (4)

5% Sodium Fluoride (NaF) Varnish

EXPERIMENTAL

Caries-active children aged 6-8 years. 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 teeth 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. Saliva samples collected at T0, T1 and T2. n=20.

Other: 5% Sodium Fluoride Varnish

2% Chlorhexidine Pre-Treatment + 5% NaF Varnish

EXPERIMENTAL

Caries-active children aged 6-8 years. Teeth are gently air-dried for 30 seconds under isolation. 2% CHX is applied to the lesion/tooth surfaces using an applicator tip and left for 30 seconds. Excess CHX is absorbed, an additional 30 seconds was allowed to pass.NaF varnish was then applied and left for 1 minute. Precautions are taken to prevent CHX ingestion. Parents are instructed to restrict water and hard food intake for 1 hour post-application. Saliva samples collected at T0, T1 and T2. n=20.

Other: 2% Chlorhexidine Pre-Treatment + 5% NaF Varnish

Standard Care / Oral Hygiene Education

ACTIVE COMPARATOR

Caries-active children aged 6-8 years. No professional topical agent is applied. Children and parents receive standardized oral hygiene education including twice-daily brushing with fluoride toothpaste, reduction of sugar frequency, and a brief parent information brochure. Necessary treatment will be offered at the end of the study upon request (wait-list design). Saliva samples collected at T0 and T2. n=20.

Behavioral: Standard Oral Hygiene Education

Caries-Free Healthy Control

NO INTERVENTION

Age- and sex-matched caries-free children (ICDAS II = 0, dmft = 0) aged 6-8 years. No intervention is applied. Clinical assessment (dmft/ICDAS) is performed and recorded. Saliva sampling is performed at T0 only. This group serves as a non-randomized biological reference group. n=20.

Interventions

5% Sodium Fluoride Varnish OTHER

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.

5% Sodium Fluoride (NaF) Varnish

2% Chlorhexidine Pre-Treatment + 5% NaF Varnish OTHER

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.

2% Chlorhexidine Pre-Treatment + 5% NaF Varnish

Standard Oral Hygiene Education BEHAVIORAL

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).

Standard Care / Oral Hygiene Education

Eligibility Criteria

• Age: 6 Years - 8 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Children aged 6-8 years with all first permanent molars erupted
• For active caries groups (Groups A, B, C): participants must meet at least one of the following criteria: dmft ≥ 6, or presence of at least one active caries lesion with an ICDAS code ≥ 3, or clinical evidence of active caries on ≥ 10 surfaces
• For the dmft = 0 reference group (Group D): all surfaces caries-free and non-high-risk individuals (ICDAS II = 0); only baseline (T0) saliva sampling will be performed
• No professional topical fluoride application or continuous CHX use within the past 3 months
• No systemic chronic disease, immunodeficiency, or severe neuromotor disorder
• No gingival redness, swelling, or bleeding
• Written parental informed consent obtained

You may not qualify if:

• Known allergy to fluoride compounds or varnish components
• Behavioral problems that would prevent safe cooperation during application
• Regular antibiotic use within the past 1 month
• Individuals with infectious diseases
• Those at high risk of endocarditis
• History of substance dependence
• Epilepsy
• Renal failure or immunosuppression

Sponsors & Collaborators

• Gül Keskin: lead
• Alanya Alaaddin Keykubat University: collaborator

Study Sites (1)

Alanya Alaaddin Keykubat University, Faculty of Dentistry

Alanya, Antalya, 07450, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Dental Caries

Condition Hierarchy (Ancestors)

Tooth Demineralization; Tooth Diseases; Stomatognathic Diseases

Study Officials

• GÜL KESKİN, DDS, PhD

  Alanya Alaaddin Keykubat University

  STUDY DIRECTOR

Central Study Contacts

GÜL KESKİN, DDS, PhD

CONTACT

905444468857; gul.keskin@alanya.edu.tr

BİNNUR B ÖZDEMİR, DDS

CONTACT

905069033834; busra.ozdemir@alanya.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: This is an open-label study. Masking of the participants and the clinical investigator is not feasible due to the visible and procedurally distinct nature of the interventions (5% NaF varnish, 2% CHX + 5% NaF varnish, and oral hygiene education only). However, to minimize potential assessment bias, the laboratory personnel performing the ELISA-based salivary biomarker analyses (IL-6, MMP-8, MMP-9, TIMP-1) will be blinded to the group assignments and clinical status of the participants. All saliva samples will be identified solely by coded numbers, ensuring that the biomarker quantification process remains objective and unbiased.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Associate Professor Dr.

Model Details: This is a single-center, parallel-group, randomized controlled, open-label clinical study. Biomarker measurements will be evaluated objectively. Blinding of the application is not practically feasible due to the nature of the procedures. Additionally, a non-randomized reference group consisting of healthy individuals with dmft = 0 will be included in the study for comparison purposes. Children with active caries participating in the study have been randomized with equal probability into three intervention groups (5% NaF, 2% CHX + 5% NaF, Negative control). Randomization was performed using computer-assisted random methods to prevent selection bias. The healthy, caries-free control group (Group D) was selected on a non-randomized basis.

Study Record Dates

• First Submitted: May 20, 2026
• First Posted: May 27, 2026
• Study Start: May 15, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): June 30, 2027
• Last Updated: June 2, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)