Comparative Study of Anti-COVID Mouthwash and Remineralization Agents on Dentinal Tubular Occlusion: An In Vitro Study

Published In: Journal of International Society of Preventive and Community Dentistry
Publication Year: 2024

Study Design

This is a laboratory-based interventional in vitro study designed to assess the impact of anti-COVID hydrogen peroxide (HP) mouthwash and two remineralization agents—CPP-ACP and nano-hydroxyapatite (n-HAP)—on dentinal tubule occlusion in human molar dentin discs.

Funding Sources

The study reports no financial support or sponsorship and declares no conflicts of interest.
It was approved by the Ethics Committee of Zahedan University of Medical Sciences, Iran (IR.ZAUMS.REC.1399.301) and conducted as part of a dental thesis project.

PICO Framework – What Was Studied and How?

Population:
Human permanent molar dentin disks from extracted healthy teeth (due to periodontal reasons), cut to 1.5 mm thickness.

Intervention:
Application of:

• 1.5% hydrogen peroxide (HP) mouthwash (preprocedural rinse)

• Followed by either:

  • Artificial saliva

  • CPP-ACP paste

  • Nano-hydroxyapatite (n-HAP) toothpaste

Comparison:
Control groups included:

• Untreated dentin disks

• Dentin disks demineralized using EDTA

• EDTA + HP only (no further treatment)

Outcomes:
Degree of dentinal tubular occlusion, measured by scanning electron microscopy (SEM) and scored (1 to 4) by two observers.
Score 1 = no occlusion, Score 4 = almost all tubules occluded.

In Paragraph Form:
This in vitro study analyzed whether anti-COVID hydrogen peroxide mouthwash affects dentin sensitivity by influencing dentinal tubule occlusion and whether this effect can be counteracted by remineralization agents such as CPP-ACP or nano-hydroxyapatite. Tubular blockage was measured using SEM scoring.

Inclusion and Exclusion Criteria

Inclusion Criteria:

• Healthy human molars extracted for periodontal reasons

• No caries, cracks, or restorations

• Uniform dentin disks of 1.5 mm thickness

Exclusion Criteria:

• Disks with cracks or surface porosity

Demographics and Study Design

Total Samples: 80 dentin disks from 30 human molars
Group Distribution:

• Group 1: Untreated control – 5 disks

• Group 2: EDTA treated only – 15 disks

• Group 3: EDTA + 1.5% HP – 15 disks

• Group 4: EDTA + HP + Artificial saliva – 15 disks

• Group 5: EDTA + HP + CPP-ACP – 15 disks

• Group 6: EDTA + HP + n-HAP – 15 disks

Primary Outcome Variable Results

Outcome: SEM-observed dentinal tubule occlusion (Scores 1–4)

Key Findings:

• n-HAP group had the highest rate of tubule occlusion (66.7% Score 3, 26.7% Score 4).

• The CPP-ACP group was effective but slightly less so (86.7% Score 3, 0% Score 4).

• HP-only and EDTA groups showed minimal occlusion (mostly Score 1).

• Statistical significance was confirmed by Kruskal–Wallis test (P < 0.0001).

Conclusions

• 1.5% HP mouthwash, though important for infection control, does not improve dentinal occlusion and may even contribute to demineralization.

• Nano-hydroxyapatite toothpaste showed the most promising results in sealing dentinal tubules post-HP use.

• CPP-ACP provided moderate occlusion but was less effective than n-HAP.

• n-HAP is a strong candidate for managing dentin hypersensitivity in patients using anti-COVID mouthwash before dental procedures.

Discussion: Strengths and Limitations

Strengths:

• Double-observer SEM evaluation with high inter-rater agreement (Kappa = 0.829, P = 0.0001)

• Clear and structured in vitro design

• Use of established scoring system

Limitations:

• In vitro design does not replicate full oral conditions (e.g., saliva dynamics, plaque)

• Short-term observation—long-term effects on remineralization unknown

• Specific formulations (e.g., pH of HP) may not match commercial products

Citation

Soleimanyfar MF, Hosseini Tabatabaei S. Comparative study of anti-COVID mouthwash and remineralization agents on dentinal tubular occlusion: An in vitro study. J Int Soc Prev Community Dent. 2024;14(6):453-460.
PubMed Link: https://pubmed.ncbi.nlm.nih.gov/

Visual Aids

Simple Chart: Tubule Occlusion Scores