Influence of Mixed Additives on the Physicochemical Properties of a 5.25% Sodium Hypochlorite Solution: An Unsupervised Multivariate Statistical Approach

• Published in: Journal of endodontics Vol. 44; no. 2; pp. 280 - 285.e3
• Main Authors: Dragan, Oana, Tomuta, Ioan, Casoni, Dorina, Sarbu, Costel, Campian, Radu, Frentiu, Tiberiu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-02-2018
• Subjects: Cluster analysis; Dentistry; principal component analysis; sodium hypochlorite; surface tension; viscosity; Cluster analysis; pH; viscosity; sodium hypochlorite; surface tension; principal component analysis
• ISSN: 0099-2399; 1878-3554
• DOI: 10.1016/j.joen.2017.08.006

This article reports for the first time the effects of multiple additives (polyethylene glycol 400, Triton X-100, benzalkonium chloride, and ethyl formate) on the surface tension, pH, and viscosity of 5.25% sodium hypochlorite (NaOCl) irrigant solution. Advanced statistical approaches based on unsupervised multivariate analysis (cluster analysis and principal component analysis) were used to quantify the variability of the physicochemical properties of the modified NaOCl solution for the first time in dentistry.
Solutions of 5.25% NaOCl were modified with multiple additives in various concentrations, physicochemical parameters were measured at 22°C and 37°C, and the results were statistically analyzed to group the solutions and reveal the effects of additives.
Cluster analysis and principal component analysis revealed that pH and surface tension were the significant parameters (P < .05) for grouping the modified solutions. Four principal components, accounting for 90.6% of the total variance, were associated with flow characteristics (37.3%) determined by polyethylene glycol; the wetting property (22.5% and 10.5%), which was dependent on cationic and nonionic surfactant; and the antimicrobial effect (20.3%) influenced by ethyl formate. Varimax rotation of the principal components showed that the cationic surfactant (benzalkonium chloride) had significantly decreased surface tension compared with the nonionic surfactant (Triton-X). Although ethyl formate was introduced as an odor modifier, it had a significant effect on pH decrease and the occurrence of effervescence with O2 and hypochlorous acid release.
The statistical results revealed that the 5.25% NaOCl irrigant solution should be modified with a mixture of 0.1% benzalkonium chloride, 1% ethyl formate, and 7% polyethylene glycol for obtaining a low pH and low surface tension.
•We report the effect of multiple additives (polyethylene glycol 400, Triton X-100, benzalkonium chloride, and ethyl formate) on the surface tension, pH, and viscosity of 5.25% sodium hypochlorite (NaOCl) irrigant solution.•Unsupervised multivariate analysis (cluster analysis and principal component analysis) was used for the first time to quantify the variability of physicochemical properties of modified NaOCl solution.•pH and surface tension were determined to be the significant parameters for grouping the modified solutions.•Benzalkonium chloride significantly decreased the surface tension of modified NaOCl solution compared with Triton X-100.•The decrease in the pH of 5.25% NaOCl solution and the development of effervescence with hypochlorous acid and O2 release in the presence of ethyl formate were shown.