Clinical, Cosmetic and Investigational Dentistry (Jul 2021)
The Potential of Hydroxyapatite Toothpaste to Prevent Root Caries: A pH-Cycling Study
Abstract
Bennett Tochukwu Amaechi,1 Thais Santiago Phillips,1 Veronica Evans,1 Chidera Precious Ugwokaegbe,2 Minh Nguyet Luong,1 Linda Oge Okoye,3 Frederic Meyer,4 Joachim Enax4 1Department of Comprehensive Dentistry, School of Dentistry, University of Texas Health San Antonio, San Antonio, TX, 78229-3900, USA; 2Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA; 3Department of Restorative Dentistry, Faculty of Dentistry, College of Medicine, University of Nigeria, Enugu, Nigeria; 4Research Department, Dr. Kurt Wolff GmbH & Co. KG, Bielefeld, GermanyCorrespondence: Bennett Tochukwu AmaechiDepartment of Comprehensive Dentistry, School of Dentistry, University of Texas Health San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229-3900, USATel +1 210 567 3185Email [email protected]: The effectiveness of a hydroxyapatite (HAP) toothpaste and a fluoride toothpaste in preventing root tissue demineralization (root caries) was compared using an established pH-cycling caries model.Materials and Methods: Sixty dentin blocks were produced from the root tissue of extracted human teeth and were assigned to 3 test groups (n=20/group): 10% hydroxyapatite toothpaste (HAP), 1450 ppm fluoride toothpaste (fluoride), and artificial saliva (artsaliva). Early root caries lesions were developed in each sample by 7-day demineralization using a pH-cycling caries model. The daily cyclic treatment regimen consists of two 2-minute toothpaste-slurry treatment periods, one 6-hour acid challenge using acidified gel (pH 4.5), and then storage in remineralizing solution (artsaliva) for the rest of the time. Demineralization was assessed as the amount of mineral loss (∆z) using transverse microradiography (TMR). Pairwise comparisons (between treatments) were performed using analysis of variance (ANOVA), and then Tukey’s HSD for multiple comparisons. All p-values are considered significant if p< 0.05.Results: Both ANOVA and Tukey’s HSD indicated no significant (ANOVA; n=20) difference in mean ∆z among the groups, with least ∆z (±Sd) in the HAP (1117± 366) compared to fluoride (1392± 334) and artsaliva (1406± 223). Relative to control, HAP and fluoride inhibited root demineralization by 21% and 6%, respectively.Conclusion: Within the limit of the present study, the tested toothpaste containing 10% HAP is an effective root caries control toothpaste. Toothpaste containing 10% HAP was slightly more effective in preventing tooth demineralization than 1450 ppm fluoride provided as sodium fluoride. Thus, this study shows that HAP toothpastes can serve as an effective alternative to fluoride toothpastes for root caries management.Keywords: hydroxyapatite, fluoride, pH cycling, artificial saliva, demineralization, toothpaste
