Evaluation of Dentifrice Containing Nano-hydroxyapatite for Dentinal Hypersensitivity: A Randomized Controlled Trial

Published In: Journal of International Oral Health
Publication Year: 2015

Study Design

This was a randomized, double-blind, parallel-group clinical trial, conducted over four weeks at a single dental center in Chennai, India.

Funding Sources

The article lists no specific funding and states no conflicts of interest.

PICO Framework – what was studied and how?

Population:
Adults aged 18–60 years with a history of dentin hypersensitivity to thermal or sour stimuli, with no periodontal therapy in the past year.

Intervention:
Use of a dentifrice containing nano-hydroxyapatite (nano-HAP).

Comparison:
Use of a dentifrice containing 5% calcium sodium phosphosilicate (NovaMin), a standard desensitizing agent.

Outcomes:
Reduction in dentinal hypersensitivity, measured via Visual Analog Scale (VAS) using three stimuli: tactile test, air blast, and cold water application.

In Paragraph Form:
This randomized controlled trial examined whether a nano-hydroxyapatite toothpaste could reduce dentinal hypersensitivity more effectively than a standard toothpaste containing NovaMin. The population included adults with known sensitivity, and outcomes were measured via validated tests that simulate real-world triggers of hypersensitivity, with responses scored using a visual analog scale.

Inclusion and Exclusion Criteria

Inclusion Criteria:

• History of hypersensitivity to hot, cold, or sour stimuli

• No periodontal therapy in the past year

• Willingness to participate

Exclusion Criteria:

• Active caries, attrited or chipped teeth

• Recent use of anti-inflammatory/analgesic medication

• Recent periodontal surgery (within 6 months)

• Presence of dentures or bridges interfering with evaluation

• Pregnancy or lactation

Demographics and Study Design

• Total participants: 36 (20 males, 16 females)

• Groups:

  • 18 subjects used the nano-HAP dentifrice

  • 18 subjects used the NovaMin dentifrice

All participants brushed twice daily for 4 weeks using the assigned dentifrice with a standard toothbrush.

Primary Outcome Variables and Results

Pain levels were assessed using the Visual Analog Scale (VAS) from 0 (no pain) to 10 (extreme pain) across three tests: cold, air blast, and tactile.

Within-Group Sensitivity Reduction (After 4 Weeks)

Between-Group Comparisons

➡️ No statistically significant difference was found between the two products.

Conclusions

Both nano-hydroxyapatite and NovaMin toothpastes showed significant reductions in dentinal hypersensitivity over a 4-week period. The nano-HAP formulation was equally effective as the benchmark NovaMin-containing toothpaste, suggesting it can be a viable alternative for managing sensitivity symptoms.

Discussion: Strengths and Limitations

Strengths:

• Double-blind design minimized bias.

• Used three distinct sensitivity measures for robust assessment.

• Incorporated validated pain measurement (VAS).

• Well-aligned with clinical guidelines and ADA recommendations.

Limitations:

• Small sample size (n=36).

• Short duration (4 weeks); long-term effects unknown.

• Conducted at a single center, limiting generalizability.

• Specific toothpaste brands were de-identified during testing, but from a scientific reproducibility standpoint, this limits formulation transparency.

Despite these limitations, the study provides important early clinical evidence supporting nano-hydroxyapatite's use in sensitivity management.

Citation

Nithin G, John J, Nagappan N, Prabhu S, Senthilkumar E. Evaluation of dentifrice containing nano-hydroxyapatite for dentinal hypersensitivity: A randomized controlled trial. J Int Oral Health. 2015;7(8):118–122.
🔗 PubMed Link 

Visual Aid

Table: Sensitivity Score Reduction After 4 Weeks (VAS Scores)

Note: "NS" indicates not statistically significant between groups.