Dentin erosion by whitening mouthwash associated to toothbrushing abrasion: A focus variation 3D scanning microscopy study

Abstract

The aim of this study was to determine the erosive potential of hydrogen peroxide (HP) containing mouthwash on dentin assessed by Focus variation three-dimensional (3D) microscopy. Twenty dentin slabs were selected and randomly allocated into two groups (n = 10): DW--Distilled water (pH = 7.27) and HP-1.5% (pH = 3.78). Each specimen was cyclically demineralized (4 × 60 s/day, 10 days) with HP or DW and brushed 3×/day (200 g, 150 strokes--toothpaste with 1,450 ppmF as NaF). Between the challenges, the specimens were exposed to artificial saliva. Afterward, dentin loss was analyzed using focus variation 3D microscopy, and the data were submitted to unpaired t-test (α = 0.05). Statistically significant difference was found between the mean wear rate (μm, ±SD) of HP (1.98 ± 0.51) and DW (1.45 ± 0.39). The results suggest that the use of HP-containing mouthwash associated to brushing may increase the risk of tissue loss and focus variation 3D microscopy may be used as a technique for quantifying dental wear.

In vitro evaluation of modified surface microhardness measurement, focus variation 3D microscopy and contact stylus profilometry to assess enamel surface loss after erosive–abrasive challenges

“…The latter has the advantage of being non-damaging and sometimes scans take only a few seconds [28, 29]. FVM is able to make a three-dimensional topographic surface analysis directly by optical imaging, with a vertical resolution of up to 10 nm [14, 29, 30]. This technique is ideal for the measurement of surface roughness and maximum peak-to-valley distance or for measuring the effect of toothpastes on enamel [30, 33–35].…”

“…FVM is able to make a three-dimensional topographic surface analysis directly by optical imaging, with a vertical resolution of up to 10 nm [14, 29, 30]. This technique is ideal for the measurement of surface roughness and maximum peak-to-valley distance or for measuring the effect of toothpastes on enamel [30, 33–35]. Moreover, steep vertical structures can also be captured with FVM [14, 28].…”

“…20% and 5%, respectively (Fig 1). This average height difference was considered to represent enamel surface loss (expressed in μm) [21, 30]. …”

Evaluation of ex vivo effectiveness of commercial desensitizing dentifrices

“…The buccal surface of the specimen was abraded using a belt sander (Politriz PL02, Te-clago, Brazil), with decreasing grit sandpaper (1200, 2400 and 4000) under digital pressure to the exposure of the dentin surface (13). Then, the specimens were sectioned so that they reached the dimensions 4 x 4 x 2 mm (4,14). The specimens were cleaned with an ultrasonic cleaning tank (USC1400, Unique, Brazil) and ultrapure water (Direct-Q®, Millipore, France) for three cycles of 10 minutes each, in order to remove impurities, followed by washing by ultrapure water three more times (2).…”

Enamel erosion and prevention efficacy characterized by confocal laser scanning microscope

“…This has been recently applied to the analysis of eroded enamel surfaces to assess quantitative of tissue loss (Heurich et al, ). More recently, the 3D focus varying microscope (FVM) also shows sensitive in detecting structural changes following erosive and abrasive processes, and it could also perform optical scans of the surface in three dimensions, and calculate surface roughness quantitatively without any surface damages (Lima et al, , Passos et al, , Ren et al, ).…”