Salivary fluoride concentrations following toothbrushing with experimental toothpaste containing surface pre-reacted glass-ionomer (S-PRG) filler.

Abstract

Single-blind 9 case comparative studies were conducted to evaluate salivary fluoride concentrations following toothbrushing using experimental toothpaste containing surface pre-reacted glass-ionomer (S-PRG) fillers. Preliminary tests were conducted in order to determine the volume of usage as well as the concentrations (wt %) of S-PRG filler. Based on the results given these experiments, we compared the salivary fluoride concentrations following toothbrushing with 0.5g of 4 different types of toothpastes: 5 wt % S-PRG filler, 1400ppm F AmF (amine fluoride), 1500ppm F NaF (sodium fluoride), and MFP (monofluorophosphate) containing toothpaste. Of the 12 participants, 7 participated in the preliminary study and 8 in the main study. All participants brushed their teeth using the scrubbing method for 2min. At first, 1.0 and 0.5g of 20 wt % S-PRG filler toothpastes were used to compare, then followed by 0.5g of 0 (control), 1, and 5 wt % S-PRG toothpastes, respectively. The participants spat out once and rinsed with 15mL of distilled water for 5s. Saliva was collected for 3min each at different time intervals of 0 (baseline), 5, 10, 15, 30, 60, 120, and 180min after the rinsing. Fluoride concentrations were determined using a fluoride electrode, and the area under the salivary clearance - time curve (AUC: ppm‧min) of each toothpaste was calculated as the salivary fluoride retention. The main study was then conducted to evaluate the salivary fluoride concentrations as well as the AUC value using 0.5g of 5 wt % S-PRG filler toothpaste, followed by NaF, MFP, and AmF toothpastes. Since there were no statistical differences between using 1.0 and 0.5g of 20 wt % S-PRG toothpastes in salivary fluoride concentrations as well as the AUC value throughout the 180min measurement, the volume was set as 0.5g for the following studies. Concentrations of 5 and 20 wt % S-PRG toothpastes retained 0.09ppm F or more in saliva even after 180min. No statistical differences were seen in the salivary fluoride concentrations at any time intervals as well as the AUC value between 5 and 20 wt % S-PRG toothpastes. Based on these results, the concentration of 5 wt % S-PRG toothpaste was used for the main comparative study. MFP toothpaste resulted in by far the lowest salivary fluoride concentrations (0.06ppm F at 180min) and the AUC value (24.6ppm‧min), whereas 5 wt % S-PRG toothpaste (0.15ppm F at 180min, 92.3ppm‧min) displayed retention on par with AmF toothpaste which appeared to result in higher values (0.17ppm F at 180min, 103ppm‧min), compared to NaF toothpaste (0.12ppm F at 180min, 49.3ppm‧min). The salivary fluoride concentrations following toothbrushing with 0.5g of 5 wt % S-PRG filler containing toothpaste showed retention similar to the best performing 1400ppm F AmF toothpaste even 180min after toothbrushing.