In vitro effects of alcohol-containing mouthwashes on human enamel and restorative materials

Effect of whitening concepts on surface roughness and optical characteristics of resin-based composites: An AFM study

The aim of this study was to evaluate the effects of various whitening agents on the surface roughness and optical characteristics of different types of resin composite restorations. Fifty specimens were prepared for each resin [G-aenial Posterior (GP), SonicFill-2 (SF), Solidex (SDX), and Nova Compo HF (NC)]. Following baseline color and surface roughness (Ra) measurements, the specimens were randomly divided into 5 groups (n = 10/group) according to whitening concepts: control (distilled water), in-office bleaching [OB-(Opalescence Boost)], at-home bleaching [HB-(Opalescence PF)], whitening toothpaste [WT-(Signal White Now)], and whitening mouthwash [WM-(Listerine Advanced White)]. ∆E00 , ∆TP00 , and ∆WID values were calculated before and after the whitening procedure with a spectrophotometer using the CIEDE2000 formula. Surface roughness measurements were repeated. The surface topography was determined using atomic force microscopy. Two- and three-way analyses of variance and Tukey's post-hoc test were performed, with p < 0.05 regarded as indicative of significance. No significant differences were detected among the resin composite materials in terms of the ΔE00 values (p > 0.05). Color change of all resin materials was above the AT threshold (>1.8) and the PT threshold (>0.8). All restorative materials presented acceptable (AT<2.62) TP00 values. Solidex specimens demonstrated the lowest WID values compared to the other composites. There were significant differences among the whitening procedures with respect to ΔE00 , ΔTP00 , and WID values (p < 0.001). SF/WT combination showed the highest and clinically unacceptable ΔE00 values. The highest roughness values were observed in the SDX specimens and the combination of SDX/OB. The effect of whitening agents on the optical characteristics and surface roughness of restorative materials depends on the type of material, agent, and time. RESEARCH HIGHLIGHTS: Clinicians should be aware that long-term use of over-the-counter products due to the abrasive effects of their ingredients and repeated bleaching session applications may affect the color stability and surface roughness of resin composites.

Effect of Anti-COVID-19 Mouthwashes on Shear Bond Strength of Resin-Matrix Ceramics Repaired with Resin Composite Using Universal Adhesive: An In Vitro Study

Using anti-COVID-19 mouthwashes has become necessary to reduce acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmissions. Resin-matrix ceramic (RMCs) materials that are exposed to mouthwashes may affect the bonding of repaired materials. This research was performed to assess the effects of anti-COVID-19 mouthwashes on the shear bond strengths (SBS) of RMCs repaired with resin composites. A total of 189 rectangular specimens of two different RMCs (Vita Enamic (VE) and Shofu Block HC (ShB)) were thermocycled and randomly divided into nine subgroups according to different mouthwashes (distilled water (DW), 0.2% povidone–iodine (PVP-I), and 1.5% hydrogen peroxide (HP)) and surface treatment protocols (no surface treatment, hydrofluoric acid etching (HF), and sandblasting (SB)). A repair protocol for RMCs was performed (using universal adhesives and resin composites), and the specimens were assessed using an SBS test. The failure mode was examined using a stereomicroscope. The SBS data were evaluated using a three-way ANOVA and a Tukey post hoc test. The SBS were significantly affected by the RMCs, mouthwashes, and surface treatment protocols. Both surface treatment protocols (HF and SB) for both RMCs, whether immersed in anti-COVID-19 mouthwash or not, improved the SBS. For the VE immersed in HP and PVP-I, the HF surface treatment had the highest SBS. For the ShB immersed in HP and PVP-I, the SB surface treatment had the highest SBS.

The Effects of Selected Mouthwashes on the Surface Microhardness of a Single-shade Universal Resin Composite: In Vitro Study

Aim:

To investigate the effects of selected alcohol-free mouthwashes with different formulations (zinc-hydroxyapatite, hydrogen peroxide, and sodium fluoride) on the surface microhardness of a single-shade universal resin composite.

Materials and Methods:

Forty disc-shaped specimens (8 × 2 mm) from the universal resin composite (Omnichroma®), and a nano-hybrid composite (Tetric® N-Ceram) were prepared. After polymerization, baseline surface microhardness values were recorded using Vickers microhardness tester. The samples from each material were randomly assigned to 4 groups ( n = 10) and immersed in 20 ml of the mouthwashes: Biorepair®, Listerine®, Colgate® Optic White, and distilled water (control). The samples were kept in the immersion solutions for 24 hours, and post-immersion microhardness values were recorded. Data were analyzed with one-way ANOVA and paired sample t-tests at p < .05.

Results:

Significant reduction in microhardness was observed in all resin composite groups after immersion in the mouthwashes compared to baseline values ( p < .0001). The highest microhardness reduction in Omnichroma® group was observed after immersion in Colgate® Optic White; and Tetric® N-Ceram group after immersion in Listerine® mouthwash. For both materials, the least reduction in microhardness was observed after immersion in Biorepair®. Microhardness values for Omnichroma were significantly higher than Tetric® N-Ceram ( p < .0001). However, Omnichroma exhibited a significantly greater reduction in microhardness after immersion in the tested mouthwashes.

Conclusion:

In vitro simulated use of the investigated mouthwashes negatively affected the surface microhardness of both tested resin composites. The observed effects were both mouthwash and material dependent.

Title Cross-Sectional Study to Evaluate Knowledge and Attitudes on Oral Hygiene of Romanian Students

Background and Objectives: the purpose of this study was to evaluate students’ level of knowledge and attitude towards oral hygiene. Materials and Methods: the evaluation was carried out by a questionnaire, with 30 Q (questions) as follows: demographic data (Q1–Q5), oral hygiene knowledge data (Q6–Q23) and oral hygiene attitude data (Q24–Q30). The study included students from Romanian schools and the selection of the study group was made following selection criteria in accordance with ethical issues. A descriptive statistical analysis was performed and a value of p ≤ 0.05 was considered statistically significant. Results: the study included a number of 718 subjects with a mean age of 14.54 (±2.22), male 250 (34.8%) and female 468 (65.2%), MS (middle school students) 354 (49.4%) and HH (high school students) 364 (50.6%). Most of the subjects 292 (MS = 160; HS = 132) know a toothbrushing technique, p = 0.009, r = 0.091 and 587 (MS = 278; HS = 309) know that brushing removes the bacterial plaque p = 0.027, r = −0.082 but only 147 (MS = 71; HS = 76) know that (by) brushing can re-mineralize hard dental structures. The duration of the toothbrushing is variable, for 2- or 3-min p = 0.058, r = 0.043. Criteria for choosing the toothbrush were based mainly on the indications of the dentist, respectively, for toothpaste on its properties. The frequency of toothbrushing is mainly twice a day 428 (MS = 234; HS = 248), p = 0.079, r = 0.037, 73 (MS = 33; HS = 40) after every meal. p = 0.099, r = 0.095. Mouthwash is used by 421 (MS = 199; HS = 222) p = 0.111, r = −0.048, and 228 (MS = 199; HS = 222) after each brushing. Dental floss is used by 240 (MS = 106; HS = 134), p = 0.031, r = −0.073 and only 74 (MS = 41; HS = 33) after each brushing. Conclusions: there are differences in the level of knowledge and attitudes regarding the determinants of oral hygiene depending on the level of education.

How does antiseptic mouthwashes against SARS-COV-2 affect the bond strength of universal adhesive to enamel?

This study compares the effect of different mouthwashes that have been recommended during the Coronavirus disease 2019 (COVID-19) pandemic on shear bond strength (SBS) of universal adhesive to enamel in regards to self-etch (SE) and etch-and-rinse (ER) modes. Flat enamel surfaces were obtained from 100 sound human maxillary central incisors. They were randomly allocated to five groups according to the different mouthwashes (no mouthwash/control [Ctrl], 0.2% chlorhexidine 1.5% hydrogen peroxide [H2 O2 ], 0.2% povidone-iodine [PVP-I], Listerine [L]), and adhesive application modes (ER and SE) (n = 10). After the application of a universal adhesive (single bond universal), composite resin (Filtek Z250) was bonded by a cylinder-shaped mold (height: 2 mm, diameter: 2.4 mm). They were subjected to SBS test using a universal testing machine (AGS-X, Shimadzu Corp.) (crosshead speed: 1 mm/min). The resin-enamel interfaces were observed with a scanning electron microscope (SEM). The semiquantitative chemical microanalyses were performed with energy-dispersive spectroscopy (EDS). The data were statistically analyzed by two-way analysis of variance and Bonferroni test (p < .05). In SE mode, Group Ctrl revealed significantly higher SBS than all mouthwash groups (p < .05). In ER mode, Group Ctrl showed significantly higher SBS than H2 O2 and PVP-I groups (p < .05). ER mode caused significantly higher SBS than SE mode in all mouthwash groups (p < .05). The SEM observations highlighted that Group Ctrl had a regular and intact hybrid layer with resin tag formation while the H2 O2 and PVP-I groups exhibited a thin hybrid layer in both modes. EDS analysis indicated that in SE mode, all mouthwash groups presented increased O content compared to Group Ctrl. H2 O2 and PVP-I that were suggested for preprocedural use during the COVID-19 pandemic, reduced the enamel bond strength of the universal adhesive in ER mode.

Effect of mouth rinses on optical properties of CAD-CAM materials used for laminate veneers and crowns

OBJECTIVE

The purpose of this study was to investigate the effect of mouth rinses on the color and translucency of three computer-aided design and computer-aided manufacturing (CAD-CAM) restorative materials in laminate veneer and crown thicknesses.

METHODS

Specimens from two different 5Y-TZP zirconia (InCoris TZI (IT), and Zirkonzahn (ZH)) and lithium disilicate (IPS e.max CAD [IC]) in two different thicknesses (0.7 mm for laminate veneer, and 1.5 mm for crown) were sectioned. All specimens were colored with an A2-shade liquid, and the baseline color values were recorded according to the CIELab system with a spectrophotometer. Each group was divided into two subgroups (n = 15) according to the immersion solution: two different mouth rinses, KL (Klorhex), and LI (Listerine, cool mint) for 180 hours. The color coordinates (L*, a*, b*) of the specimens were measured before and after immersion in a mouth rinse, and TP and ΔE₀₀ color differences were calculated by using the CIEDE2000 color difference formula. A 3-way ANOVA, Bonferroni test, and 1-sample t tests were used to analyze the data (α = 0.05).

RESULTS

The 3-way ANOVA revealed a significant interaction of material, thickness, and mouth rinse for translucency parameter and color difference (ΔE₀₀ ) data (p < 0.001). TP decreased for both zirconia materials in laminate veneer thickness when immersed in LI mouth rinse (p < 0.05). No difference was found among the TP mean values of three materials in crown thickness after immersed in mouth rinses (p > 0.826). Both zirconia materials immersed in LI showed greater discoloration than after immersed in KL (p < 0.05). A significant difference was found in color change values among three materials for the laminate veneer thickness after immersed in LI (p < 0.001). However, all color difference values were within the clinical acceptability threshold, except for when ZH in laminate veneer thickness was immersed in LI.

CONCLUSIONS

The color change of ZH zirconia with LI mouth rinse in laminate veneer thickness was high. For both zirconia ceramics, translucency decreased and the color was less stable in laminate veneer thickness after immersed in LI compared to the crown thickness.

CLINICAL SIGNIFICANCE

The results of this in vitro study suggest that long-term use of alcohol-containing mouth rinse may alter the optical properties of tested CAD-CAM materials in tested laminate veneer thickness. For color stability with the long term use of tested mouth rinses, lithium disilicate may be preferred for both types of restorations.

Effect of mouthwashes on color stability of composite resins: A systematic review

STATEMENT OF PROBLEM

Some mouthwash ingredients may stain composite resin restorations, but how the daily use of mouthwashes might affect the color of composite resin restorations is unclear.

PURPOSE

The purpose of this systematic review was to investigate whether mouthwashes can affect the color of direct composite resin restorations.

MATERIAL AND METHODS

Bibliographical searches were carried out in PubMed, Scopus, Cochrane Library, and Web of Science databases, with no restriction on language, country, or date of publication. Studies addressing the effect of mouthwashes on the color stability of composite resins were included. The level of evidence of selected articles was determined by a qualitative scoring system and classified as high, moderate, or low.

RESULTS

Based on the search strategy, a total of 129 articles were retrieved; of which, 15 met the inclusion criteria. Most of the studies (93%) were classified as having a high level of evidence. Filtek Z350 and Listerine were the most frequently tested composite resin and mouthwash. Eight studies used distilled water as a control, 5 used artificial saliva, 1 study used an alcohol solution, and 1 did not include a control group. The composite resins were continuously immersed in the mouthwashes in 9 studies or in daily cycles in 6 studies. All studies tested the color change of the specimens after immersion in the mouthwashes. The color change was considered clinically acceptable (ΔE≤2.7) for all test mouthwashes in 10 studies.

CONCLUSIONS

Most studies reported that mouthwashes did not cause a clinically unacceptable color change in composite resins.

Over-the-counter bleaching agents can help with tooth whitening maintenance

OBJECTIVE

This study evaluated the influence of over-the-counter agents on the maintenance of color and microhardness of the enamel after home bleaching protocol.

MATERIALS AND METHODS

Specimens of bovine teeth (6 × 6 × 2 mm) were prepared, and color (Easyshade, VITA) and microhardness (HMV-2, Shimadzu) readings were performed. All the specimens were bleached using 22% carbamide peroxide (22%CP), except for the control group, and then separated into seven groups (n = 10) according to the interaction of toothpaste (whitening, conventional, and whitening with peroxide) and mouth rinse (whitening and conventional). The study simulated 1 year of toothbrushing (Pepsodent, MAVTEC) and mouth rinse by immersion. After that, final color and microhardness measurements were performed. Data were analyzed by one-way ANOVA, Tukey's test (P < .05).

RESULTS

The group submitted to 22%CP + whitening toothpaste + whitening mouth rinse showed higher color maintenance (P < .05) than the control group. The perception of whitening of teeth (ΔWI_D ) was higher than the color change (ΔE₀₀ ). There was a decrease in microhardness after treatment with 22%CP + conventional toothpaste + whitening mouth rinse.

CONCLUSIONS

Over-the-counter products can help with the maintenance of tooth whitening after bleaching with carbamide peroxide; however, special attention should be given since the association of products can also reduce the microhardness of the dental enamel.

CLINICAL SIGNIFICANCE

The association between whitening toothpastes and mouth rinses might be beneficial for maintaining color during 1 year after bleaching treatment.

Inhibitory effect of a mouth rinse formulated with chlorhexidine gluconate, ethanol, and green tea extract against major oral bacterial species

Mouth rinses are a useful supplementary tool for the prevention of oral infectious diseases. Although the antimicrobial effects of mouth rinses have been investigated, there are few studies focusing on the comparison of the effects among various oral bacterial species. In the present study, the inhibitory effect of a commercial mouth rinse, "ConCoolF," and each of its major components, chlorhexidine gluconate, ethanol, and green tea extract, on multiple species of oral bacteria were investigated. Inhibition of bacterial growth was observed in all cariogenic streptococcal species with different genera, serotypes, and strains isolated from different countries when either the complete mouth rinse or chlorhexidine gluconate were used. However, no growth inhibition was observed when the bacteria were exposed to ethanol or green tea extract. Interestingly, growth inhibition was greatly reduced in non-cariogenic streptococci compared with cariogenic streptococci. In addition, both the mouth rinse and chlorhexidine gluconate inhibited the biofilms formed by both Streptococcus mutans (S. mutans) and Porphyromonas gingivalis (P. gingivalis), among which the inhibitory effect against S. mutans was higher than that against P. gingivalis. These results suggest that a mouth rinse containing chlorhexidine gluconate, ethanol, and green tea extract, or chlorhexidine gluconate alone, exhibits antimicrobial activity against several oral bacteria species, having greater activity against pathogenic bacteria.

Colour stability and surface properties of high-translucency restorative materials for digital dentistry after simulated oral rinsing

High-translucency restorative materials are commonly used in the restoration of anterior teeth where aesthetics is a critical factor. In this in vitro study, the impact of mouthwash on the colour stability and surface characteristics of high-translucency computer-aided design and computer-aided manufacturing (CAD-CAM) dental restorative materials was evaluated. Two-hundred specimens were fabricated from five high-translucency CAD-CAM materials: a resin nano ceramic; a polymer-infiltrated ceramic network; a feldspathic ceramic; a lithium disilicate glass ceramic; and high-translucency zirconia. Each group of ceramic specimens was then divided into four subgroups: conventional mouthwash (LISTERINE); whitening mouthwash (LISTERINE Healthy White); chlorhexidine gluconate; and distilled water. Oral rinsing was simulated at 100 rpm for 180 h, representing 15 yr of clinical simulation. The specimens were then evaluated for colour, translucency, gloss, roughness, and surface morphology. Two-way ANOVA and linear mixed models were used for intergroup comparisons (α = 0.05). The polymer-infiltrated ceramic network and feldspathic ceramic became brighter, more opaque, less glossy, and rougher after rinsing with the whitening mouthwash. The long-term use of specific mouthwashes can cause deterioration of the optical and surface properties of high-translucency CAD-CAM dental restorations.

Effect of mouth rinses on tooth enamel surface

This study aims to evaluate the effect of mouth rinses on the color, microhardness, and surface roughness of tooth enamel. Sixty dental blocks were collected from human third molars and divided in five groups (n = 12): the control group (CG) without immersion in mouth rinse, Listerine Zero, Colgate Plax Fresh Mint, Listerine Whitening, and Colgate Luminous White. The groups were subjected to initial color analysis; the microhardness and roughness of the enamel surfaces were evaluated. Next, the samples were subjected to immersion in mouth rinses or brushing with conventional fluoride toothpaste (CG) according to the manufacturer's instructions; after a 12-week treatment, the color, microhardness, and roughness were once again assessed and compared with the initial analysis. Data were tabulated and analyzed through a two-way analysis of variance (ANOVA) (color and roughness) followed by Tukey's test. Microhardness was analyzed through the Kruskal-Wallis test followed by Dunn's test; the level of significance was 5%. All groups immersed in mouth rinses had a higher level of microhardness loss than CG; additionally, all groups showed changes in the enamel surface. Enamel surface loss was observed using a roughness test, and the mouth rinses promoted a higher level of color changes than CG. Given the results, it can be concluded that the mouth rinses led to significant changes in tooth enamel.