Lene Hystad Hove

The protective effect of TiF4, SnF2 and NaF against erosion-like lesions in situ.

The aim of this in situ study was to compare the protective effect of TiF4, SnF2 and NaF on the development of erosion-like lesions in human enamel. Fourteen human molars were each divided into 4 specimens, mounted on acrylic mouth appliances and worn by 7 volunteers for 9 days. In order to mimic a feasible treatment procedure for patients with voluntary or involuntary gastric reflux, the specimens were etched for 2 min twice a day (0.01 M HCl) and fluoride applications were performed every third day (2 min). The controls were treated as the other specimens except for the fluoride applications. Etch depths and surface roughness changes (Rq) were measured by white light interferometry. Compared with the control, TiF4 and SnF2 reduced the etching depth by 100% (p < 0.001) and 91% (p < 0.001), respectively, and both treatments resulted in an observable surface layer. NaF had no significant protective effect (p = 0.46). It can be concluded that although SnF2 provided significant protection for the enamel surfaces, TiF4 showed the best protection against acid attack, while NaF had no significant protective effect in this study.

The Protective Effect of TiF4, SnF2 and NaF on Erosion of Enamel by Hydrochloric Acid in vitro Measured by White Light Interferometry

The purpose of this in vitro study was to compare the protective effect of TiF4, SnF2 and NaF (all 0.5 M F) on the development of erosion-like lesions in human dental enamel. Four enamel specimens from each of 6 extracted molars were polished and embedded in epoxy resin. The enamel surfaces of 3 specimens from each tooth were treated with the different fluoride solutions for 2 min. Following fluoride treatments, the specimens were immersed in 0.01 M HCl (pH 2.0), for 2, 4 and 6 min in order to mimic a gastric reflux situation. One specimen from each tooth was used as a control and was only exposed to acid. The etching depths (in micrometres) after 6 min were: TiF4 0.8 (SD 0.8), SnF2 3.5 (SD 0.7), NaF 5.3 (SD 0.4), and 7.0 (SD 0.3) for the control specimens. Compared to the control, TiF4 protected the enamel surface from acid attack almost completely (88%), while SnF2 reduced the etch depth after 6 min by 50% and NaF by 25%.

Reliability of Two Clinical Scoring Systems for Dental Erosive Wear

The aim of the study was to evaluate and compare two dental erosive wear scoring systems, the Visual Erosion Dental Examination (VEDE) and Basic Erosive Wear Examination (BEWE). Seventy-four tooth surfaces (photographs) and 562 surfaces (in participants) were scored by 5 (photographs) or 3 (in participants) clinicians using both scoring systems. The surfaces in the photographs were scored twice. The level of agreement was measured by weighted kappa (ĸw). Inter- and intraexaminer agreement showed small variations between the examiners for both systems when scoring the photographs. Slightly higher mean ĸw values were found for VEDE (ĸw = 0.77) compared with BEWE (ĸw = 0.69). When scoring the surfaces in the clinical examination the mean ĸw values for the two systems were equal (ĸw = 0.73). Interexaminer agreement using VEDE was calculated to see how differentiation between enamel and dentine lesions influenced the variability. The highest agreement was found for score 0 (sound, 86%) and score 3 (exposure of dentine, 67%), while the smallest agreement was shown for score 1 (initial loss of enamel, 30%) and score 2 (pronounced loss of enamel, 57%). The reliability of the two scoring systems proved acceptable for scoring the severity of dental erosive wear and for recording such lesions in prevalence studies. The greatest difficulties were found when scoring enamel lesions, especially initial lesions, while good agreement was observed when examining sound surfaces (score 0) and dentine lesions (score 3).

The erosion-inhibiting effect of TiF4, SnF2, and NaF solutions on pellicle-covered enamel in vitro

Objective. The aim of this study was to compare the protective effect of TiF4, SnF2, and NaF treatment on the development of erosion-like lesions in pellicle-covered human enamel. Material and Methods. Twelve human molars were each divided into 5 specimens, 4 of which were immersed in saliva for 2 h. Three pellicle-covered specimens from each tooth were treated with a TiF4, SnF2, or NaF solution (all 0.5 M F) for 2 min. Control specimens, one with and one without pellicle, were included. Immersion in acid (0.01 M HCl) was carried out stepwise (2+2+2+2 min). The etching depths (in µm) were measured using white light interferometry. Results. Compared with the control with pellicle, TiF4 reduced enamel loss by 100% after 2 min and by 24% after 8 min of acid exposure. The corresponding values for SnF2 were 45% and 14%. NaF provided no significant protection of the surface. The pellicle-covered specimens showed reduced lesion depths after 6 and 8 min compared to the controls without pellicle. Conclusions. TiF4 gave the best protection against acid attack. SnF2 provided significant protection only after 2 min of acid exposure, while NaF had no significant protective effect.

An in vitro study on the effect of TiF(4) treatment against erosion by hydrochloric acid on pellicle-covered enamel.

The aim of this in vitro study was to examine the effect of fluoride treatment on pellicle-covered enamel exposed to an acidic challenge simulating gastric reflux. Sixteen bovine and 16 human teeth were sectioned into four pieces, divided into four groups: (1) control, (2) 2-hour pellicle, (3) TiF4, and (4) 2-hour pellicle + TiF4, and subsequently subjected to 3 ml 0.01 M HCl stepwise for 4 + 4 + 4 min. The acid was analysed for calcium by atomic absorption spectroscopy. TiF4 reduced Ca release from enamel by 76, 57 and 56% following the 4 + 4 + 4-min acid exposures, respectively, in bovine and 44, 54 and 54% in human enamel. These results suggest that treatment of enamel with a TiF4 solution, with or without pellicle removal, may provide protection for the enamel against acid attack.

Dental erosive wear among Norwegian wine tasters

Abstract Objective. To assess the prevalence and severity of dental erosive wear among a group of professional wine tasters. Material and methods. Eighteen wine tasters currently employed at AS Vinmonopolet, Norway (3 women, 15 men; mean age 39 years) and 30 comparison participants (9 women, 21 men; mean age 39 years) were included in the study. The wine tasters were examined by four calibrated clinicians using the Visual Erosion Dental Examination system. Data concerning medical and dietary history, oral hygiene habits and occupational background were obtained from a self-completed questionnaire. Data were analyzed using Fishers exact test, and examiner agreement was determined by means of linear-weighted kappa and the intra-class correlation coefficient. Results. Nine (50%) of the wine tasters and six (20%) of the comparison group showed clinical signs of dental erosion. Among the wine tasters, 39% had dentine involvement, compared to just 7% of the comparison group. The erosive lesions were mainly found on the occlusal surfaces of mandibular first molars in the wine tasters, whereas for the controls, the palatal surfaces of upper centrals were most often affected. Conclusions. There was a significant difference in the prevalence of dental erosive wear between the two groups, the wine tasters having a higher prevalence and more severely affected surfaces than the comparison group. Half of the wine tasters had no erosive wear and, for the other half, there was no relationship between the duration of their professional life and the extent of erosive wear.

A qualitative and quantitative investigation into the effect of fluoride formulations on enamel erosion and erosion–abrasion in vitro

OBJECTIVES To investigate the effect of a single application of highly concentrated SnF(2) and NaF solutions and a NaF/CaF(2) varnish on human enamel subjected to hydrochloric acid erosion and tooth brush abrasion. METHODS Forty enamel samples were prepared from human third molars and NaF (9500ppm, pH 8.0), SnF(2) (9500ppm, pH 2.6) solutions; Bifluorid10(®) varnish (42,500ppm, NaF 5%, CaF(2) 5%) and deionized water (control) was applied to the enamel. Following this three, six and nine cycles of erosion [1 cycle=erosion (0.01M HCl, pH 2.2, 2min)+artificial saliva (1h, pH 7.0)] and erosion-abrasion [1 cycle=erosion (0.01M HCl, pH 2.2, 2min)+artificial saliva (1h, pH 7.0)+abrasion (120 linear strokes in artificial saliva from Tepe medium soft brushes 200g loading)] were carried out. The fluoride treated enamel was analysed using Knoop microhardness, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). RESULTS For erosion alone, there was significantly less microhardness reduction in the Bifluorid10(®) group after three and six cycles of erosion (P<0.05), however no other groups showed statistically different hardness (P>0.05). The EDS analysis showed that only the Bifluorid10(®) group had any detectable fluorine following erosion and erosion-abrasion (0.1wt.% and 0.2wt.% fluorine respectively). The surface fluorine was found to have been removed after erosion and erosion-abrasion for all other surface treatments. Although precipitates were observed after application of the surface treatments, following erosion-abrasion, no visible surface effects from any fluoride preparation remained. CONCLUSIONS Enamel surface precipitates from application NaF, SnF(2) solutions appear to not be able to provide protection against gastric erosion and tooth brush abrasion. The NaF/CaF(2) varnish provided limited protection against erosion but the role for such varnishes in gastric erosion and tooth brush abrasion remains uncertain.

Protective effect of TiF(4) solutions with different concentrations and pH on development of erosion-like lesions.

Aim: To evaluate how concentration and pH of TiF4 influence the erosion-protective effect. Methods: Specimens were treated with a TiF4 solution: (1) 0.5 M F, pH 1.2, (2) 0.05 M F, pH 2.1, (3) 0.5 M F, pH 2.1, or (4) 0.05 M F, pH 1.2; then, they were exposed to HCl. Results: After 2 min, the proportions of the area covered with the coating were 93, 71, 17 and 0% in groups 1–4. When present, the coating seemed to protect the surface. After 6 min, a coating could only be seen in group 1 (43%). Conclusion: Reducing the concentration of TiF4 and increasing the pH of the solution decreased the protective effect.

The Effect of Daily Fluoride Mouth Rinsing on Enamel Erosive/Abrasive Wear in situ

It is not known whether application of fluoride agents on enamel results in lasting resistance to erosive/abrasive wear. We investigated if one daily mouth rinse with sodium fluoride (NaF), stannous fluoride (SnF2) or titanium tetrafluoride (TiF4) solutions protected enamel against erosive/abrasive wear in situ (a paired, randomised and blind study). Sixteen molars were cut into 4 specimens, each with one amalgam filling (measurement reference surface). Two teeth (2 × 4 specimens) were mounted bilaterally (buccal aspects) on acrylic mandibular appliances and worn for 9 days by 8 volunteers. Every morning, the specimens were brushed manually with water (30 s) extra-orally. Then fluoride solutions (0.4% SnF2 pH 2.5; 0.15% TiF4 pH 2.1; 0.2% NaF pH 6.5, all 0.05 m F) were applied (2 min). Three of the specimens from each tooth got different treatment, and the fourth served as control. At midday, the specimens were etched for 2 min in 300 ml fresh 0.01 m hydrochloric acid and rinsed in tap water. This etch procedure was repeated in the afternoon. Topographic measurements were performed by a white-light interferometer. Mean surface loss (±SD) for 16 teeth after 9 days was: SnF2 1.8 ± 1.9 µm, TiF4 3.1 ± 4.8 µm, NaF 26.3 ± 4.7 µm, control 32.3 ± 4.4 µm. Daily rinse with SnF2, TiF4 and NaF resulted in 94, 90 and 18% reduction in enamel erosive/abrasive wear, respectively, compared with control (p < 0.05). The superior protective effect of daily rinse with either stannous or titanium tetrafluoride solutions on erosive/abrasive enamel wear is promising.

Comparing Different Methods to Assess Erosive Lesion Depths and Progression in vitro

The aim of this study was to compare the precision and accuracy of 5 different methods applied to assess surface substance loss or changes in surface microhardness (SMH) on the same enamel surfaces after repeated acid exposures. Ground specimens from human molars were exposed to 0.01 M HCl (pH 2.2) for 6 min × 2 and measurements performed 3 times to estimate precision. The accuracies (systematic errors) were calculated against the manufacturer’s calibration standard. Lesion depth progression was from 94 to 110%, related to repeated acid exposure. The precisions/accuracies were: WLI (white light interferometry), 0.5/0.4%; SP (stylus profilometry), 4.7/0.7%; OP (optical profilometry), 1.4/12%; AAS (atomic absorption spectroscopy), 0.4/17% (measured calcium loss was converted to lesion depth). The correlation between WLI and SP was R2 = 0.98, and between WLI and OP it was R2 = 0.85. SMH gave information on qualitative changes of the surface (precision: 5.5%, accuracy: 4.0%). WLI performed best in precision and accuracy, but SP, OP and AAS are all relevant methods for analysing lesion depths and progression, SMH seems suitable for analysing minor changes in surface enamel only.