TiF4 gel effects on tubular occlusion of eroded/abraded human dentin

This in situ study evaluated the tubular occlusion caused by 4% TiF4 gel on the surface of eroded/abraded dentin. Sixty human dentin samples were eroded in vitro and assigned into six groups (n=10) according to the in situ surface treatment and number of cycling days: 4% TiF4 gel applied once (TiF(4)1), twice (TiF(4)2), or three times (TiF(4)3) followed by 2, 4, and 6 days of erosive/abrasive in situ cycling, respectively. Control groups (no treatment) were subjected to 2 (C1), 4 (C2), and 6 (C3) days of erosive/abrasive in situ cycling only. A seventh group (n=10) was comprised by in vitro uneroded samples (UN), subjected to 6 days of in situ erosive/abrasive cycling. Each cycling day consisted on six erosive (0.5% citric acid, pH 2.6) and one abrasive events. Environmental scanning electron microscopy micrographs were taken. For all groups, blinded examiners assessed dentin tubules occlusion using visual scores (0unoccluded, 1partially occluded by granular deposits, 2partially occluded by reduction in tubular lumen into diamond shape, 3completely occluded) on images captured prior and after the in situ phase. Scheirer-Ray-Hare test demonstrated that treatments significantly affected tubule occlusion (p<.001). Dunn's test showed that tubule occlusion in TiF(4)3 was significantly higher than in C1. Tubule occlusion in remaining groups did not differ from that observed in groups TiF(4)3 and C1. Tubule occlusion was significantly higher after in situ phase. It may be suggested that TiF4, when applied three times, was able to positively change tubule occlusion of dentin samples. (AU)