Inter-method reliability for determining total and soluble fluorides in child low-fluoride formula dentifrices

Area of Science:

• Analytical Chemistry
• Materials Science
• Dental Materials

Background:

• Accurate fluoride determination is crucial for dental product safety and efficacy.
• Existing methods for analyzing fluorides in child formula dentifrices (CFD) vary in complexity and reliability.
• Standardization of analytical methods ensures consistent quality control in dental product manufacturing.

Purpose of the Study:

• To compare the inter-method reliability (IMR) of three distinct analytical techniques for quantifying total fluorides (TF) and total soluble fluorides (TSF) in CFD.
• To evaluate the suitability of the ISO 19448:2018 Modified Direct Method (MDM) as a reliable alternative to direct acid-hydrolysis (DM) and modified Taves acid-HMDS diffusion analysis (TAD).
• To assess the statistical agreement and potential biases among the compared methods using IMR and Intraclass Correlation Coefficient (ICC) analyses.

Main Methods:

• Comparative analysis of three methods: Direct Method (DM), Modified Direct Method (MDM) (ISO 19448:2018), and Modified Taves acid-HMDS diffusion analysis (TAD).
• Application of Inter-method reliability (IMR) statistical approach to assess agreement between methods.
• Utilized Intraclass Correlation Coefficient (ICC) analysis to quantify measurement reliability across different models, measures, and fluoride types in five child formula dentifrices (CFD).

Main Results:

• Significant differences in mean differences were found across methods, except between DM and TAD for TF (p=0.622).
• Proportional bias was observed between DM and TAD for TF (p<0.001).
• All measurements showed significant reliability (p<0.001); however, IMR between DM and TAD was lower than MDM and TAD for consistency/absolute agreement.

Conclusions:

• The ISO 19448:2018 Modified Direct Method (MDM) demonstrates high reliability for determining TF and TSF in CFD.
• MDM can be reliably used as an alternative to both Direct Method (DM) and Modified Taves acid-HMDS diffusion analysis (TAD).
• The study validates MDM as a consistent and dependable method for fluoride analysis in child-specific dental formulations.