A Fluoride-Calcium-Phosphate Treatment Produced Persistent Reduction in Dentin Hydraulic Conductance
Objectives: This study evaluated the effectiveness of a new 2-step treatment employing a fluoride-calcium-phosphate (FCP) complex solution in reducing dentin hydraulic conductance (HC), which represented dentin sensitivity in this in vitro model.
Methods: Dentin discs preparation and HC measurements method were previously described (Cherng et al 2006). Twenty-seven dentin discs were divided into three equal-sized groups such that the mean baseline HC were statistically equivalent among the groups. Group 1 discs received a 1-min application of an activation solution (0.6M NaF and 0.83M KH2PO4) followed by a 3-min application of an FCP (0.6M NaF, 2M CaCl2, and 0.1M H3PO4) solution. Group 2 (positive control) discs received a 1-min treatment of Gluma™ per manufacturers’ instructions. Group 3 (negative control) discs received 1-min treatment with phosphate buffered saline (PBS). After the treatment, each disc was rinsed with PBS for 15s, and HC was measured. The disc was then brushed for 30s (Ranir GBL110), rinsed with PBS and HC was measured again. Each disc was then subjected to a 5d cyclic de-/re-min regimen (Takagi et al 1997). The HC of each disc was measured again before and after brushing.
Results: Results are presented as % reductions from the baseline HC of the same disc. After the treatments, the reductions (mean±s.d.; n=9) of the 3 groups were (1) 88.1±4.3, (2) 30.1±12.3, and (3) 8.8±12.9. After brushing: (1) 74.4±9.2, (2) 20.3±13.1, and (3) -3.8±22.5. After the de/re-min regimen: (1) 81.6±9.8, (2) 41.8±11.8, and (3) 17.8±29.1. After final brushing: (1) 79.1±6.9, (2) 31.9±10.1, and (3) 11.0±30.1. ANOVA results indicated that mean HC of all three groups were significantly different (p<0.05) at each time point
Conclusions: Both FCP and Gluma™ produced significant reductions in dentin HC that endured brushing and cyclic pH challenges. FCP was more effective than Gluma™ at each time point.