Effect of cigarette smoke on color stability and surface roughness of dental composites

Long-term clinical comparison of a resin-based composite and resin modified glass ionomer in the treatment of cervical caries lesions

This 72-month study compared the clinical effectiveness of a resin-based composite (RBC) (Spectrum TPH3, Dentsply Sirona) with a resin-modified glass ionomer cement (RMGIC) (Riva Light Cure, SDI) in restoring cervical caries lesions (CCLs). Thirty-three patients, each with at least two CCLs, were enrolled. After caries removal, the dimensions of the cavities were recorded. In a split-mouth study design, a total of 110 restorations were randomly placed. Fifty-five restorations were placed with RBC using an etch-and-rinse adhesive system (Prime&Bond NT, Dentsply Sirona), while the remaining 55 were restored with RMGIC. The restorations were assessed at baseline, 6, 12, 18, 24, 36, 60, and 72 months according to modified USPHS criteria. Statistical analysis included Pearson Chi-square, Friedman tests, Kaplan Meier, and Logistic Regression analysis (p < 0.05). After 72 months, 47 restorations in 19 patients were evaluated (55% follow-up rate). Seventy-five percent of the RBC (n = 26) and 74% (n = 21) of the RMGIC restorations were fully retained. There were no significant differences between materials regarding retention and marginal adaptation (p > 0.05). Cavity dimensions, caries activity, and retention exhibited no correlation (p > 0.05). The increase in marginal staining in both groups over time was significant (p < 0.001). RMGIC restorations exhibited higher discoloration than RBC restorations (p = 0.014). At 72 months, three secondary caries lesions were detected in both restoration groups: two RMGIC and one RBC. There were no reports of sensitivity. After 72 months, both RBC and RMGIC restorations were clinically successful, with similar retention and marginal adaptation scores. However, it is noteworthy that RMGIC restorations tend to discoloration over time compared to RBC. The trial is registered in the database of "Clinical Trials". The registration number is NCT0372-2758, October 29, 2018.

Impact of smoking on resin bonded restorations: A narrative review

INTRODUCTION

Smoking is a common risk factor for multiple diseases, including diabetes mellitus, cardiovascular diseases, pulmonary diseases, and different cancers. It is an established cause of multiple oral health conditions, in addition to adversely impairing the appearance of oral tissues. Smoking has also been identified to impact dental restorations' functional and esthetic aspects. This narrative review is focused on the significance of the esthetic consequences of smoking on resin-based dental restoration. It provides an understanding of the challenges dental professionals and patients face.

METHODS

A literature search was conducted to identify studies on the impact of smoking exposure on the esthetic appearance of composite restorations. The inclusion criteria were met by five studies selected for analysis.

RESULTS

The studies revealed that conventional cigarettes cause more noticeable color changes than electronic cigarettes. Additionally, the choice of composite material significantly influences the color stability of dental restorations. Exposure to both smoking and staining agents could worsen the color alterations in dental restorations. Smokers may benefit from dental ceramics, which offer better aesthetics. Quantitative insights into these effects can be gained by incorporating delta E (ΔE) values and fluorescence intensity in esthetic evaluations.

CONCLUSIONS

The studies provide valuable insights into the multiple factors that can impact the aesthetics of dental restorations. Dental professionals should take into account the smoking type, composite material, and patient habits when planning treatments. Utilizing ΔE values and fluorescence intensity in esthetic evaluations can provide a more comprehensive understanding. Future research should focus on longitudinal studies, alternative materials, and individual patient profiles.

Cigarette smoke and tobacco heating aerosol on the aging of clear aligners

BACKGROUND

The treatments with clear aligners (CA) showed an exponential higher percentage in the last years being almost invisible with major patient acceptability and a resulting improvement in quality of life. CA are composed of thermoplastic polyurethane not inert but subjected to changes due to heating and humidity, chewing forces, and prolonged exposure to enzymes in saliva in the oral cavity and external factors. Cigarette smoke (CS) and the aerosol produced by tobacco products with reduced health risks may be considered among the external factors affecting CA. The purpose of this study was the assessment of optical properties (absorbance and transmittance) and roughness of CA after in vitro aging due to exposition to CS and THS2.2, compared to controls. The secondary objective will be the investigation of CS and THS2.2 effects on resin composite inside aligners used for attachments during treatment with CA.

METHODS

A total number of 60 CA units will be used and equally divided in three different groups (20 in each): CS group exposed to reference cigarettes smoking, THS2.2 group exposed to aerosol from 20 heat-not-burn sticks, and control group, CG to pure air only. The aligners will present ten introflection for the attachments on the anterior part. In accordance with ISO standard 3402, 3R4F cigarettes and THS2.2 tobacco sticks must undergo conditioning for a minimum of 48 hours and a maximum of 21 days at a temperature of 22±1 °C and a relative humidity of 60±3%.

RESULTS

Using spectrophotometry, the optical characteristics (absorbance and transmittance) of each aligner will be evaluated after aging (Jasco UV-vis V630PC, Tokyo, Japan). Each aligner will be cut with a rotating saw from canine to canine prior to the measurements in order to lop off the lingual region and displaying the labial barrier. The absorbance and transmittance measurements will be collected and statistically analyzed with a significance of P<0.05.

CONCLUSIONS

Surface roughness of the aligners and attachments inside them will be assessed by 3D scanning microscopy (Infinite Focus G4h). Color of resin composite will be assessed using the (CIE Lab) Commission Internationale de l'Eclairage L*a*b* color space by means of Olympus CrystalEyef dental spectrophotometer. Clinicians should advise patients to refrain from smoking and drinking coffee or tea while wearing aligners for two reasons: first, the color change is unacceptably noticeable when wearing aligners, and second, the material's chemical composition may be slightly altered, which could affect the intended dental movements.

The influence of smoking on the effectiveness of at-home bleaching: A prospective clinical study

OBJECTIVES

To evaluate the effect of smoking on tooth whitening and color change after at-home bleaching.

MATERIALS AND METHODS

This prospective clinical study evaluated two groups of participants: NS-non-smokers (n = 24) and S-smokers (n = 16). All subjects were treated with at-home bleaching using 22% carbamide peroxide (CP) for 1 h/day for 14 days. Color coordinates (L*-luminosity, a*-red-green axis and b*-yellow-blue axis) were obtained before bleaching (D0-baseline), 1 day (D1), 15 days (D15), and 1 month (D30) after bleaching. The whiteness index (WID ) and CIEDE2000 color differences (ΔE00 ) were calculated for S and NS. Color changes between S and NS subjects for specific teeth (CI-Central Incisors, LI-Lateral Incisors, and C-Canines) were analyzed using the Mann-Whitney test (α = 0.05).

RESULTS

There was no significant difference in WID between S and NS subjects at baseline. NS participants showed higher WID than S at D1, D15, and D30 (p < 0.05). NS showed higher ΔWID for CI and C between D0 and the other evaluation times (D1, D15, and D30) compared to S. Smokers showed higher darkening of CI than NS in ΔWID D30-D1 (p < 0.05). Color changes showed similar overall behavior for ΔWID . For all evaluation times, ΔWID and ΔE00 values were below the corresponding acceptability thresholds.

CONCLUSION

At-home bleaching was effective on smokers and nonsmokers. Smoking negatively affected color stability after bleaching. ΔE00 and ΔWID were acceptable for both groups.

CLINICAL SIGNIFICANCE

Although smoking negatively affected color stability after bleaching, the observed changes were clinically acceptable.

Effect of immersion and thermocycling in different beverages on the surface roughness of single- and multi-shade resin composites

BACKGROUND

Resin composite restorations are highly esthetic restorations, which should have and maintain high surface polish. However, esthetic restorations are subjected to different beverages at variable temperatures, which may affect their surface roughness. This study aimed to evaluate the surface roughness of single-shade (Omnichroma) and multi-shade (Filtek Z350XT) composite materials, following aging by immersion and thermocycling in different beverages, simulating one year of clinical service.

METHODS

Thirty specimens of each material were prepared and divided into 6 subgroups (n = 5). In each material, the grouping of the specimens was as follows: the first subgroup was the as-prepared specimens stored dry without immersion or thermocycling. The second, third, and fourth subgroups were immersed in saliva, tea, and red wine, respectively, for 12 days at 37 °C. The fifth and sixth subgroups were thermocycled for 10,000 cycles, in tea (the fifth between 37 and 57 °C) and in red wine (the sixth between 37 °C and12°C). The resultant surface roughness was measured by two different methods, stylus profilometer and atomic force microscopy (AFM). Intergroup comparison was performed using independent t test, while intragroup comparison was performed using one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test.

RESULTS

Intergroup comparison between both composites showed no statistically significant differences in all groups using the stylus profilometer roughness measurements (P>0.05), while the AFM measurements showed significant difference (P ≤ 0.05) within all storage media except the as-prepared control (P = 0.0645), where nanofilled Filtek Z350 XT showed lower nano-roughness. Intragroup comparison data were variable, depending on the material, aging conditions, and roughness assessment tool. However, the resultant average surface roughness (R_a) values in all groups did not exceed the threshold value of R_a 0.2 μm.

CONCLUSIONS

Both resin composites attained and retained a clinically acceptable surface finish after immersion and thermocycling in different beverages.

Color stability of resin-based composites exposed to smoke. A systematic review

OBJECTIVE

To conduct a systematic review on color stability of dental resin-based composites (RBC) exposed to conventional and electronic cigarettes.

MATERIALS AND METHODS

In vitro studies reporting on the color stability of RBC exposed to conventional cigarettes or to e-cigarettes: both Tobacco Heating Systems (THS) and Electronic Nicotine Delivery Systems (ENDS). The quality of the included studies was assessed with the QUIN tool (risk-of-bias tool for assessing in vitro studies conducted in dentistry). A systematic search, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed on four (n = 4) databases (Embase, Medline, Scopus, Web of Science) for articles published until March 28th, 2022.

RESULTS

Of the 365 screened articles, 13 were included in this review. All the included articles analyzed conventional cigarette smoke (CS), four analyzed Electronic Nicotine Delivery Systems (ENDS) and two Tobacco Heating Systems (THS). In terms of study design, smoke exposure time, smoke flow, type and number of cigarettes a high variability was reported.

CONCLUSIONS

The available evidence suggests that CS smoke significantly affects color stability. Electronic cigarettes show less color change that seems to be easily recovered under clinical acceptability thresholds, although evidence is scarce.

CLINICAL SIGNIFICANCE

Clinicians should be aware, and should therefore warn their patients, that RBCs are subjected to irreversible color change if exposed to smoke. Electronic cigarettes (both ENDS and THS) induce less color change that can be recovered with repolishing or whitening procedures.

Effects of Smokeless Tobacco on Color Stability and Surface Roughness of 3D-Printed, CAD/CAM-Milled, and Conventional Denture Base Materials: An In Vitro Study

Tobacco consumption in its different forms can affect the optical and surface properties of dental materials that are used in the oral cavity. Thus, the present study was conducted to evaluate the effects of two commercially available smokeless tobacco products on the color stability and surface roughness of denture base resins that were fabricated using three different techniques (CAD/CAM milling, 3D printing, and conventional heat polymerization). A total of 126 denture base resin specimens were fabricated using the three different manufacturing techniques (n = 42 each). Specimens from each group were further subdivided into three subgroups (n = 14 each) and immersed in three different immersion media (a khaini suspension, a tabbaq suspension, and artificial saliva). The differences in color and surface roughness were assessed according to data that were collected and statistically analyzed using SPSS version 24.0. The tabbaq smokeless tobacco was found to cause greatest changes in color and surface roughness; the effect was observed to be highest in the 3D-printed specimens followed by the conventional heat-polymerized and CAD/CAM milled specimens. The mean changes in color and surface roughness were the highest for the tabbaq smokeless tobacco followed by the khaini smokeless tobacco and the artificial saliva. Statistically significant (p-value < 0.05) differences were observed among all techniques and suspensions. We concluded that the mean changes in color and surface roughness were significantly higher for the 3D-printed dentures compared to the conventional heat-polymerized and CAD/CAM-milled dentures. Thus, the results of the present study strengthened the concept that tobacco in any form can lead to changes in the color and surface roughness of denture base materials.

Effect of tobacco and nicotine in causing staining of dental hard tissues and dental materials: A systematic review and meta-analysis

INTRODUCTION

Dental staining is a common concern for tobacco users. However, little is known about which components of tobacco are responsible for the staining and whether nicotine may be implicated. This is of increasing relevance with the popularity of novel products such as heated-tobacco products and electronic cigarettes (E-cigarettes).

OBJECTIVES

This systematic review aimed to establish the evidence base for the effect if any, of the various tobacco and nicotine products in causing staining of dental hard tissues and materials.

MATERIAL AND METHODS

This systematic review was performed in accordance with the preferred reporting items for systematic reviews and meta-analyses guidelines. There were four structured population intervention comparison outcomesquestions. A search was conducted up to December 2021 in three databases: MEDLINE, EMBASE, and Web of Science, and manual searching of relevant sources was also completed. Two researchers individually reviewed the titles then abstracts and finally full articles. A reporting quality appraisal was conducted appropriately to the study methodology.

RESULTS

Of the 815 records titles identified, 56 full-text articles were assessed for eligibility, of which 27 were included for analysis. The included studies were mainly laboratory studies of varying reporting quality. There was evidence from 18 studies that tobacco exposure caused staining of dental hard tissues (pooled results from three studies- enamel/dentine; mean difference [MD]: 16.22; 95% confidence interval[12.11, 20.32; I² : 96%)and materials (pooled result from four studies-resin composite; MD: 11.90; 95% CI: 11.47, 12.34; I² : 100%). There was limited evidence that E-cigarettes 99%) and heated tobacco products (HTPs; pooled results from three studies--1.07, 6.54; I² : 99%) cause staining, but this was lower than with traditional tobacco/found 11 compounds, of which 8 were terpenoids, from tobacco products implicated in causing staining. Finally, there was some evidence that resin composites stained more than other materials.

CONCLUSIONS

Tobacco smoking causes dental staining. There was limited evidence that E-cigarettes and HTPs did cause dental staining that was less intense than that caused by traditional tobacco products.

Effect of cigarettes smoke on bonded polymeric restorations: OCT study

Background

Up to date, the effect of cigarette smoke (CS) on the adhesive properties of the restorative materials bonded to tooth structure is still unclear. It is still questionable if it interferes with the durability and clinical success of these restorations. Few numbers of studies reported the assessment of microgaps of dental composite using cross-polarization optical coherence tomography (CP-OCT). The aim of this study was to evaluate the presence of interfacial microgaps between composite resin restoration and the tooth structure with or without exposure to CS under the CP-OCT.

Materials and methods

In this in-vitro study, a standardized round class-V cavities were prepared in twenty extracted, caries-free human molar teeth, and they were divided randomly into two groups (n = 10). Adhesive system (Gluma universal, Kulzer GmbH) was applied followed by filing the prepared cavities with flowable composite restoration (Charisma, Kulzer GmbH). Then, exposure to CS (40 cigarettes/day) was carried out for 14 days and the samples were stored in normal saline solution after each smoke exposure cycle. Next, all samples were immersed in ammoniac silver nitrate for 24 h, followed by immersion in a photo-developing solution for 8 h. Optical comparison was carried out by CP-OCT to assess microgaps percentage between smoke (SG) and non-smoke groups (NSG) at the axial walls (AW) and cavity floor (CF).

Results

Independent T-test showed that there was a significant difference between the two groups (SG, NSG) in AW microgaps percentage (p = 0.008), while there was no difference in CF (p = 0.15).

Conclusion

It can be inferred from the current finding that OCT can be used to predict the adaptability of the bonded restoration under the thermochemical influence. CS has a negative effect on the marginal integrity of the bonded polymeric restorations.

The Effect of Smoking and Brushing on the Color Stability and Stainability of Different CAD/CAM Restorative Materials

This study aimed to investigate and compare the color stability and stainability of computer-aided design/computer-aided manufacturing (CAD/CAM) restorative materials in their glazed (G) and polished (P) state when exposed to cigarette smoke, as well as after brushing. Three CAD/CAM restorative materials were investigated: lithium disilicate CAD (LD), zirconia (Zr), and Telio PMMA CAD (PMMA), according to their surface finishing and assignment to cigarette smoking exposure or soaking in the saliva (control) group. The color change (∆E) was calculated before and after the intervention performed for all specimens, using the L*a*b values to quantitatively assess the shade differences. Statistical analysis was performed using one-way repeated measures ANOVA and Bonferroni multiple comparison analysis (α = 0.05). The surface finishing did not influence the materials’ stainability. Color change was noted after smoking, LD and Zr-G and Zr-P had a comparable color change (p > 0.05), while PMMA presented lower ∆E values (p < 0.05). After brushing, all specimens had a significant color change that was high for LD-G and LD-P, and Zr-G, compared with Zr-P and PMMA (p < 0.05). In conclusion, the exposure to cigarette smoke showed that LD, Zr, and PMMA are all susceptible to staining, but brushing decreases surface staining.

Effect of cigarette smoke on aesthetic brackets: an in vitro study

Objective:

The objective of this study was to evaluate the effect of cigarette smoke (CS) on physical and mechanical properties of ceramic, polycarbonate and alumina ceramic brackets. The null hypothesis tested was that aesthetic brackets would not be influenced by CS.

Methods:

Ninety aesthetic brackets were allocated to three groups (n = 30): ceramic (GCE), polycarbonate (GCO) and alumina ceramic (GPS). Ten samples of each group were assigned to color and surface roughness analysis, performed before (T₀) and after (T₁) exposure to CS; and twenty samples were allocated into control and experimental groups (n = 10) (not exposed and exposed to CS, respectively) for shear bond strength test (SBS). Exposure to CS followed an adaptation of the method described by Le Mesurier. Colorimetric reading, surface morphology and roughness, SBS and adhesive remnant index (ARI) were assessed. Statistical analysis comprised independent and paired t-tests, ANOVA/Tukey and Fisher’s exact tests (α = 0.05).

Results:

Changes were observed in brackets’ color (NBS: GCE = 2.4; GCO = 1.9; GPS = 2.1), surface roughness (ΔRa: GCE = 1.1 ± 0.8 µm; GCO = 1.9 ± 1.5µm; GPS = -0.3 ± 0.1 µm / ΔRz: GCE = 1.4 ± 1.0 nm; GPS = -0.5 ± 0.1 nm); and SBS (GPS - experimental = 221.8 ± 48.6 N) after exposure to CS (p< 0.05).

Conclusions:

Exposure, in vitro, of aesthetic brackets to CS resulted in changes of color to darker and more opaque shades, surface roughness alterations, and higher SBS values. ARI scores were not associated with exposure to CS.

In vitro procedures for color stability evaluation of dental resin-based composites exposed to smoke: A scoping review

The objective of this study was to review the experimental in vitro procedures employed to assess the color stability of resin-based composites exposed to smoke. A literature search was performed on four databases (Pubmed, Scopus, Embase, and Web of Science). The quality of the included papers was assessed with the Cochrane risk-of-bias tool (RoB 2). In total, 25 studies were selected for full-text reading, from which 12 were included in the review. The assessed variables were: dimensions, shape, time before exposure, finishing, smoke-type, exposure time, brushing simulation, color, measuring system, repolishing. A disk-shaped specimen was used in most studies (n=10) with a 2 mm thickness (n=7) in custom made devices equipped with vacuum pumps or in Vitrocell systems. Spectrophotometers were the most used devices (n=11). Color differences were quantified with ΔE (n=12), ΔE00 (n=1). The large variety of staining procedures suggests the need for standardization.

Effects of conventional and heated tobacco product smoking on discoloration of artificial denture teeth

STATEMENT OF PROBLEM

Cigarette smoke can cause discoloration of artificial denture teeth. However, studies on the effects of heated tobacco product smoke on artificial denture teeth are lacking.

PURPOSE

The purpose of this in vitro study was to evaluate the effects of conventional cigarette and heated tobacco product smoke on the color stability of artificial denture teeth.

MATERIAL AND METHODS

Ninety maxillary central incisor denture teeth (Endura Anterior HC5 A3; Shofu) were randomly divided into 3 groups (n=30). Teeth in the control group were exposed to air; those in group CC were exposed to conventional cigarette (Marlboro Medium; Philip Morris) smoke, and those in group HT were exposed to heated tobacco product (IQOS 2.4 plus holder, Marlboro Heets Silver; Philip Morris) smoke. Before the experiment, the shade of the artificial denture teeth was evaluated in accordance with the Commission International de I'Eclairage (CIELab) color system by using a spectrophotometer (Shadepilot; DeguDent GmbH). The average CIELab value was estimated by scanning the entire labial surface of each specimen. To simulate smoking, standard conditions described by the Coresta Recommended Method N°22 were used-the puff duration was 2 seconds, with a 60-second interval between puffs. For each cigarette, 6 puffs and 6 intervals were simulated across 372 seconds. A total of 105 cigarettes were used based on a smoking simulation of 15 cigarettes each day for 7 days. The teeth in the control group were stored in fresh air in the smoke chamber for the same period as those in the experimental groups. After the experiment, L∗, a∗, and b∗ values were measured, and ΔE was calculated to evaluate the color change. All statistical analyses were performed with a statistical software program using a paired t test to determine discoloration after exposure to cigarette smoke. One-way ANOVA and the Tukey test were used to evaluate the significant differences between groups (α=.05).

RESULTS

Lightness was significantly lower in the CC and HT groups (P<.001). All CIELab values showed statistically significant differences in the CC group. The greatest color change was observed in the CC group (ΔE=6.93 ±0.59), whereas the HT group showed a clinically imperceptible color change (ΔE=0.79 ±0.21). Discoloration was minimal in the CC group (ΔE=0.34 ±0.13).

CONCLUSIONS

Conventional cigarette and heated tobacco product smoke can change the color of denture teeth. Heated tobacco product smoke causes less discoloration of denture teeth.

Color stability and microhardness alteration of irradiated dental enamel treated with a high fluoride concentration toothpaste

OBJECTIVES

Radiotherapy (RT) is a kind of head and neck cancer (HNC) treatment, which is associated to the habit of smoking and can develop collateral effects in the oral cavity, such as the increase of caries prevalence. This study evaluated the color alteration, the microhardness, and the remineralizing potential of high fluoride concentration toothpastes on irradiated teeth.

MATERIALS AND METHODS

Forty bovine teeth were used (6 × 6 × 2 mm) and after color (EasyShade, VITA) and microhardness initial readings were separated into two groups: exposed to cigarette smoke and non-exposed. All samples were submitted to RT (30 Gy) and to cariogenic challenge. New color and microhardness readings were done. After RT (60 Gy), the samples were submitted to simulated toothbrushing (73,000 cycles = 5 years of brushing) with two different toothpastes: conventional (1450 ppm) and high fluoride concentration (5000 ppm). Final color and microhardness readings were done after brushing. Data were analyzed with 2-way ANOVA with repeated measures and Tukey's test (p < .05).

RESULTS

There was no color difference after RT, nor after brushing (p > .05). However, after brushing, microhardness values increased for the samples treated with high fluoride concentration toothpaste (p < .05).

CONCLUSION

Radiotherapy did not influence the teeth color, and the high fluoride concentration toothpaste presented remineralizing potential; therefore, it could be used on the caries prevention related to HNC radiation.

CLINICAL RELEVANCE

Considering its remineralizing potential, toothpastes with high fluoride concentration could be a proper alternative for caries prevention in patients undergoing radiotherapy.

Color stability of resin-based composites: Staining procedures with liquids-A narrative review

OBJECTIVE

The objective of this study was to review the experimental staining procedures performed in in-vitro studies for evaluating color stability of resin-based composites used for direct restorations.

OVERVIEW

A review was performed with the purpose to identify in vitro procedures carried out to establish staining and color stability of resin-based composites used for direct restorations. A literature search was performed on four online databases (PubMed, Scopus, Embase and Web of Science) for articles published from January 1st 2001 till March 20th 2021, using a combination of free words and Medical Subject Headings (MESH) terms: "Composite Resins" AND "Color Stability" OR "Staining." Two reviewers screened titles and/or abstracts of 1728 unique studies. In total, 208 studies were selected for full-text reading, from which 178 were included in the review. The assessed variables were specimen dimensions, shape, and surface finishing; time before immersion; staining media type, dwell time, temperature and renewal interval; type of composite; color and translucency assessment parameters and measuring system. One hundred and seventy-eight articles analyzed color stability with staining liquids. Coffee was the most used staining medium (n = 102), followed by tea (n = 61), and red wine (n = 55). A disc-shaped specimen was used in most studies (n = 170) with a 2 mm thickness (n = 116). Spectrophotometers were the most used color assessment devices (n = 154), followed by colorimeters (n = 17). Color differences were quantified with ΔE (n = 154), ΔE00 (n = 23). Acceptability and or perceptibility thresholds were also taken into consideration (n = 126).

CONCLUSIONS

The large variety of staining procedure suggests the need for standardization.

CLINICAL SIGNIFICANCE

Aesthetic failure due to discoloration is a relevant clinical problem. Evaluating benefits and drawbacks of resin based composites artificial staining procedures will improve to predict materials clinical performances.

Pilot study to determine differences in breath odour between cigarette and e-cigarette consumers

Cigarette smoke is known to influence breath odour, but the effect of e-cigarettes is unknown. In this pilot study, we aimed to determine differences in breath odour between cigarette smokers (CSs) and e-cigarette consumers (ECs) in 33 healthy subjects: 11 CSs, 11 ECs and 11 non-smokers (NSs). Breath was sampled at baseline and following product use (CSs and ECs) or a waiting period (NSs) by eight trained odour judges using a six-point smoke intensity scale and a nine-point hedonic scale. We observed a statistically significant difference between CSs and ECs. Smoke intensity values were significantly higher in CSs than ECs and NSs, which were comparable both at baseline and after product use. In addition, hedonic values for CSs were significantly lower than both NSs and ECs after product use. These acute results indicate that cigarette and e-cigarette use results in significantly different breath. ECs breath has a reduced smoke odour and more pleasant aroma than CSs, and is comparable to NSs. This suggests there may be cosmetic benefits for CSs who quit smoking or switch to exclusive use of ECs. Further studies are required to understand the long-term effects of e-cigarette use on breath odour.

Impact of Smokeless Tobacco on the Color Stability of Zirconia, Zirconia-Reinforced Lithium Silicate and Feldspathic CAD/CAM Restorative Materials: An In-Vitro Study

WHO estimates that the global number of tobacco users exceeds 1.3 billion people. Few studies have examined the effect of locally made smokeless tobacco (ST) products on the color changes of material used in dental prosthetics. Bearing the recent advances in CAD/CAM ceramic restorations material in mind, this study aimed to assess ST influence on mean color change (∆E*) values among selected CAD/CAM ceramic types: multilayer zirconia (Ceramill Zolid PS), zirconia-reinforced lithium silicate ceramic (Vita Suprinity), and feldspathic (Vita TriLuxe) restorative materials. The color changes of the ceramics were compared to VITA classical and VITA 3D-MASTER shade guides. Sixty CAD/CAM ceramic specimens (20 samples each) were fabricated from Ceramill Zolid PS, Vita TriLuxe Forte, and VITA Suprinity. Specimens were prepared and divided into two groups according to the ST type and immersed for two weeks. Basic VITA classical and VITA 3D-MASTER colors were recorded at a baseline of one week and two weeks. The highest ∆E* values were recorded in the black ST for Vita Suprinity (4.77) in the first week, followed by Vita TriLuxe (4.07) in the second week. For white ST, Vita TriLuxe (4.87), and Vita Suprinity (4.42) showed extensive color change after two weeks and one week, respectively. The color change was least in zirconia for black and white ST after one week. CAD/CAM ceramic materials showed no significant difference after 1 and 2 weeks for the tested ST types. The effects of ST on CAD/CAM ceramic material (∆E* values) were high but did not reach clinically unacceptable values. Zirconia showed the least amount of color change among all the tested materials.

Effect of Conventional and Electronic Cigarettes Smoking on the Color Stability and Translucency of Tooth Colored Restorative Materials: An In Vitro Analysis

This in vitro study compared the effects of conventional and electronic cigarettes on the aesthetics (color stability and translucency) of two types of composite resins: micro and nano-hybrid. Methods: A total of 120 specimens from two different composite materials Filtek Z250 XT (Nano-hybrid, 3M) and Filtek Z250 (Micro-hybrid, 3M) were divided into four groups (n = 30); shade A2 was used. The samples were exposed to conventional and electronic cigarette smoke via a custom made chamber device. The color values and measurements were recorded using a spectrophotometer before and after the exposure. The color and translucency were evaluated using the three-dimensional CIE Lab. Results: There was a significant change in the color (ΔE) and the translucency parameter (TP) in all of the specimens exposed to electronic cigarettes and conventional cigarettes. The results showed that the highest ΔE mean is for the nano-hybrid composite exposed to conventional cigarettes with 1.74 ΔE while the same material is 0.64 under the electronic cigarettes and the difference is significant with (p < 0.05). The micro-hybrid composite data showed less changes in color under both exposures with 0.85 ΔE mean under the conventional cigarette smoke and 0.48 under the electronic cigarette smoke with (p < 0.004). Conclusions: The conventional cigarette smoke has more effect on the color stability of the composite resins than electronic cigarettes. From a clinical point of view, the effect of smoke exposure on the tested specimens’ color, for the time duration to which the specimens were exposed, were moderate (ΔE < 2). The micro-hybrid composites showed better color stability as compared to the nano-hybrid composites.

Development of a novel method to measure material surface staining by cigarette, e-cigarette or tobacco heating product aerosols

Tobacco smoke (CS) may visually stain indoor surfaces including ceilings, walls and soft furnishings over time. Potentially reduced risk products (PRRPs) such as e-cigarettes (EC) and tobacco heating products (THP) produce chemically less complex aerosols with significantly reduced levels of toxicants, particles and odour. However, the potential effects of EC and THP aerosols on the staining of indoor surfaces are currently unknown. In this study, an exposure chamber was developed as a model system to enable the accelerated staining of wallpaper and cotton samples by a scientific reference cigarette (3R4F), three THP (glo™, glo™ pro, glo™ sens) and an e-cigarette (iSwitch Maxx).

Exposure to 3R4F reference cigarettes caused the greatest level of staining, which was significantly higher than glo™, glo™ pro, glo™ sens or iSwitch Maxx aerosols, all of which showed relatively little colour change. Exposure to 200–1000 puffs of 3R4F cigarette smoke resulted in a visible dose response effect to wallpaper and cotton samples which was not observed following exposure to glo™, glo™ pro, glo™ sens or iSwitch Maxx aerosols. Aging of the samples for 4 weeks post-exposure resulted in changes to the staining levels, however PRRP staining levels were minimal and significantly lower than 3R4F exposed samples.

For the first time, diverse PRRPs across the tobacco and nicotine products risk continuum have been assessed in vitro for their impact on surface staining. CS exposure significantly increased the level of wallpaper and cotton staining, whereas exposure to glo™, glo™ pro, glo™ sens or iSwitch Maxx aerosols resulted in significantly reduced levels of staining, staining levels were also comparable to untreated control samples.

Analysis of chemical deposits on tooth enamel exposed to total particulate matter from cigarette smoke and tobacco heating system 2.2 aerosol by novel GC-MS deconvolution procedures

Tobacco smoking contributes to tooth discoloration. Pigmented compounds in the smoke generated by combustion of tobacco can cause discoloration of dental hard tissues. However, aerosols from heated tobacco products cause less discoloration than cigarette smoke (CS) in vitro. The objective of the present study was to optimize a method for extracting the colored chemical compounds deposited on tooth enamel following exposure to total particulate matter (TPM) from CS or a heated tobacco product (Tobacco Heating System [THS] 2.2), analyze the extracts by gas chromatography coupled to time-of-flight mass spectrometry, and identify the key chemicals associated with tooth discoloration. Sixty bovine enamel blocks were exposed for 2 weeks to TPM from CS or THS 2.2 aerosol or to artificial saliva as a control. Brushing without toothpaste and color measurements were performed each week. Noticeable discoloration of enamel was observed following exposure to CS TPM. The discoloration following exposure to THS 2.2 aerosol TPM or artificial saliva was not distinguishable to the eye (ΔE < 3.3). Carbon disulfide was used to extract surface-deposited chemicals. Untargeted analyses were followed by partial least squares correlation against discoloration scores (R2 = 0.96). Eleven compounds had variable importance in projection scores greater than 2. Discriminant autocorrelation matrix calculation of their mass spectral information identified eight of the eleven compounds as terpenoids. None of the compounds were related to nicotine. Several of these compounds were also detected in THS 2.2 aerosol TPM-exposed enamel, but at lower levels, in line with our findings showing less discoloration. Compared with CS TPM exposure, THS 2.2 aerosol TPM exposure resulted in lower deposition of color-related compounds on enamel surface, consistent with minimal discoloration of dental enamel.

Effect of phytosphingosine on staining resistance and microhardness of tooth enamel

OBJECTIVE

To evaluate the protective effect of phytosphingosine (PHS) against staining on dental enamel.

MATERIALS AND METHODS

Ninety-six specimens of bovine teeth (6 mm × 6 mm × 2 mm) were cut, and initial color (Easyshade, VITA), microhardness (HMV-2, Shimadzu) and fluorescence (Matlabs software, Matworks) measurements were performed. Specimens were separated into four groups according to the treatments: Distilled water (control); Human saliva (HS); PHS; PHS + HS. Specimens (n = 6) were submitted to staining procedures: Distilled water (immersion for 30 days-control); Coffee (15 minutes, twice a day/for 15 days); Black tea (as described for Coffee) and cigarette smoke (20 cigarettes/sample). Final measurements were performed, and data were analyzed (Color-CIEDE2000, fluorescence-2-way ANOVA, Tukey, and microhardness-Kruskal-Wallis Dunn, P < .05).

RESULTS

Coffee caused the highest color change (ΔE₀₀ ), followed by black tea, regardless of the treatment employed. Distilled water and cigarette smoke produced similar color changes (P > .05) for the groups control (water = 1.0 + - 0.5/ cigarette = 2.3 0.3) and PHS (water = 0.8 0.4/ cigarette = 2.3 0.4). PHS + HS demonstrated intermediate means than PHS and HS when stained with coffee and tea. After treatments, the least fluorescence alterations occurred for the groups treated with distilled water and cigarette, regardless of the treatment, with no difference (P > .05) between them. There was a significant difference (P < .05) on microhardness between all the groups, as PHS + HS > PHS > HS > Distilled water.

CONCLUSIONS

It was concluded that PHS treatment did not protect the staining of the enamel by coffee and tea, but increased the microhardness, both in the presence and absence of a salivary pellicle.

PRACTICAL IMPLICATIONS

Phytoshingosine is a novel agent and considered a promising component for anti-biofilm and anti-erosion properties by the formation of a diffusion barrier on the dental enamel. In line, PHS might be considered for anti-staining purposes.

The effect of electronic cigarettes on dental enamel color

OBJECTIVE

The use of electronic cigarettes (ECIGs) has recently increased as an alternative to conventional smoking tobacco products. The literature is scarce on the effects of ECIGs on dental and oral structures. Therefore, the objective of this study was to observe whether ECIG aerosol could alter the color of dental enamel.

MATERIALS AND METHODS

Sixty-three bovine enamel specimens were randomly separated into groups (n = 7) and treated with aerosols with different e-liquid flavors (neutral, menthol, and tobacco) and nicotine content (0, 12, and 18 mg). The initial color assessment was performed using a spectrophotometer (Easy Shade-Vita). Dental enamel was exposed to 20 cycles of ECIG aerosol in a smoking machine, and the final color was measured. The color change was evaluated using ΔEab, ΔE00, and Whiteness Index (WI_D ) formulae. Differences in L* a* b* coordinates were calculated, and data were analyzed (two-way ANOVA, uncorrected Fisher's LSD post hoc test, α = 0.05).

RESULTS

Luminosity (ΔL) was reduced by aerosols with almost all levels of nicotine content and neutral and menthol flavors. Flavored e-liquids caused more color change (P < .05) according to ΔEab and ΔE00. ΔE values from both formulae exceeded the thresholds for perceptible visual alterations of color. WI_D increased after ECIGs exposure for menthol and tobacco and decreased for neutral flavors.

CONCLUSIONS

ECIG aerosol from e-liquids with different nicotine contents and flavors altered enamel color. Menthol and tobacco e-liquids may alter the enamel color decreasing the yellowness of the enamel compared to neutral e-liquid.

CLINICAL SIGNIFICANCE

Electronic cigarettes can cause perceptible changes in tooth color, altering dental esthetics.

The Silorane-based Resin Composites: A Review

This article aims to review the research done on the silorane-based resin composites (SBRC) regarding polymerization shrinkage and contraction stresses and their ability to improve the shortcomings of the methacrylate-based resin composites (MRBC). Special attention is given to their physical and mechanical properties, bond strength, marginal adaptation, and cusp deflection. The clinical significance of this material is critically appraised with a focus on the ability of SBRC to strengthen the tooth structure as a direct restorative material. A search of English peer-reviewed dental literature (2003-2015) from PubMed and MEDLINE databases was conducted with the terms "low shrinkage" and "silorane composites." The list was screened, and 70 articles that were relevant to the objectives of this work were included.

Mass change of a sodium bicarbonate air-polished nanocomposite exposed to cigarette smoke, coffee, and red wine

Resumo Introdução As resinas compostas estão sujeitas à desafios na cavidade oral relacionados aos hábitos dos pacientes, que podem comprometer a integridade e longevidade das restaurações. As consequências da associação do consumo de bebidas e o uso de cigarros à profilaxia profissional precisam ser estudadas. Objetivo O objetivo desse estudo foi avaliar como o jateamento com bicarbonato de sódio afeta a mudança de massa (sorção e solubilidade) de uma resina composta exposta à fumaça de cigarro, vinho tinto e café. Material e método Oitenta corpos-de-prova de resina composta (FiltekZ350 XT - 3M/ESPE) foram preparados e distribuídos em 8 grupos (n=10): G1 (jateamento + água destilada), G2 (jateamento + café), G3 (jateamento + vinho tinto), G4 (jateamento + fumaça de cigarro), G5 (água destilada), G6 (café), G7 (vinho tinto) e G8 (fumaça de cigarro). Os corpos-de-prova de resina composta foram pesados em três tempos diferentes para obter M1 (massa inicial), M2 (massa após 30 dias de armazenamento nas soluções testadas e exposição ao agente) e M3 (após dessecação). Os valores de sorção e solubilidade foram calculados e analisados usando ANOVA 2-fatores e teste Tukey (5%). Resultado Os grupos experimentais tiveram maior sorção e solubilidade comparado ao grupo controle, independentemente do uso do jateamento. Não houve diferença estatística na sorção para o fator jateamento. Porém, a solubilidade foi maior nos grupos jateados. Conclusão: O jateamento com bicarbonato de sódio foi capaz de intensificar a solubilidade da resina testada, embora não tenha aumentado significativamente os valores de sorção.

Can whitening toothpastes maintain the optical stability of enamel over time?

Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth.

Staining Beverages and Cigarette Smoke on Composite Resin and Human Tooth Fluorescence by Direct Spectrometry

INTRODUCTION

This study evaluated the fluorescence intensity (FI) of different brands of composite resins (CRs) and compare those values with the FI of human tooth, under the action of cigarette smoke (CI), coffee (CA), and soft drink (CO), measured by direct spectrometry.

MATERIALS AND METHODS

A total of 30 specimens of each brand (Filtek Z350, Esthet-X, Amelogen, Durafill) were made. Others 30 tooth specimens (3 mm/diameter) were obtained from human molars using a trephine bur. The specimens were randomly divided into three groups (n = 10), according to substances: CI, CA, CO. The FI was directly measured using an optic fiber associated with a spectrometer and was measured at baseline and after staining. Data were submitted to Kruskal-Wallis, Dunnett, and Dunn tests.

RESULTS

Staining influenced FI mean values among CRs and between those with human tooth. Z showed the closest FI mean values of tooth after staining.

CONCLUSION

Staining beverages and cigarette smoke negatively influenced on FI of CR and human tooth.

CLINICAL SIGNIFICANCE

The study shows darkening treatments influenced on the fluorescent property of the dental tissues and restorative materials according to the direct spectrometry analysis.

Surface Roughness, Microhardness, and Microleakage of a Silorane-Based Composite Resin after Immediate or Delayed Finishing/Polishing

Objective. This study evaluated the effect of immediate or delayed finishing/polishing using different systems on the surface roughness, hardness, and microleakage of a silorane-based composite. Material and Methods. Specimens were made with silorane-based composite (Filtek P90, 3M ESPE) and assigned to the treatments: control (light-cured); aluminum oxide discs (Sof-Lex, 3M ESPE); diamond-impregnated silicone tips (Astropol, Ivoclar Vivadent); aluminum oxide-impregnated silicone tips (Enhance, Dentsply). Half of the specimens were finished/polished immediately and the rest after 7 days. Surface roughness (Ra, μm; n = 20) and Vickers microhardness (50 g; 45 s; n = 10) were measured. Cavities were prepared in bovine incisors and filled with Filtek P90. The fillings received immediate or delayed finishing/polishing (n = 10) and were subjected to dye penetration test (0.5% basic fuchsin, 24 h). Data were analyzed by ANOVA and Scheffe, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). Results. The finishing/polishing system significantly influenced roughness and microhardness (p < 0.0001). For enamel, microleakage was not affected by the finishing/polishing system (p = 0.309). For dentin, Sof-Lex discs and Astropol points promoted greater microleakage than Enhance points (p = 0.033). Conclusion. Considering roughness, microhardness, and microleakage together, immediate finishing/polishing of a silorane-based composite using aluminum oxide discs may be recommended.

The influence of patient characteristics on acrylic-based resilient denture liners embedded in maxillary complete dentures

PURPOSE

A major complication associated with the use of resilient denture liners (RDLs) is a change in hardness over time. In vivo studies on the deterioration of RDLs over time are needed. We aimed to investigate the influence of patient characteristics on the hardness of acrylic-based RDLs (ARDLs) embedded in complete maxillary dentures. We hypothesized that 1 month after application of the ARDLs, the hardness would be influenced by age, saliva condition, occlusal force, smoking, drinking, denture wearing during sleeping, denture cleanser usage, and denture type.

METHODS

Thirty complete maxillary denture wearers were recruited after obtaining informed consent. One investigator measured the Shore D hardness of the commercially available ARDLs, Soften (SFT), FD Soft (FDS), and Bio Liner (BIO) using a Vesmeter(®). The salivary flow rates and pH values and the occlusal force were measured for all patients before initiation of the study. T-tests and Pearson's correlation coefficients were used for the statistical analyses. A p-value of <0.05 was considered statistically significant.

RESULTS

Smoking, wearing dentures while sleeping, use of denture cleansers, and denture type were associated with an increase in the hardness of the RDLs. The resting saliva pH only influenced the hardness of the SFT ARDLs.

CONCLUSIONS

Smoking, denture wearing while sleeping, denture cleanser usage, denture type, and resting saliva pH are important predictors of the deterioration of ARDLs over time.

Correlation between three-dimentional surface topography and color stability of different nanofilled composites

AIM

The aim of this study was to evaluate the 3-dimensional (3D) surface topography and color stability of four different resin composites after immersion in different soft-beverages.

MATERIALS AND METHODS

One hundred sixty disk-shaped specimens (diameter: 10 mm, and thickness: 2 mm) were made from four different resin composites (i.e., Filtek Z550, Tetric N-Ceram, Clearfil Majesty Esthetic, and Cavex Quadrant Universal LC). Each specimen was cured under mylar strips for 20 sec for both top and bottom surfaces. All of the specimens were stored in distilled water for 24 h at 37°C. Surface measurements were carried out using a noncontact 3D-optical-profilometer in terms of surface topography (Ra values). Color measurements of each specimen were performed with Vita Easy Shade system. All the measurements were performed at baseline and after 30 days of immersion in the selected soft-beverages (Redbull, Coca-Cola and Dimes-Lemonade). Control groups were stored in distilled water during the study. Ra values and color changes (ΔE values) of the groups were recorded. The data were statistically analyzed using a one way ANOVA and Tukey's post-hoc tests (SPSS 18.0).

RESULTS

The tested soft-beverages in the present study caused color changes at a 30-day evaluation period for the tested resin composites (p < 0.05). However, 3D surface topography of resin composites was not influenced by the tested soft-beverages (p > 0.05). There was no significant interaction between the composite and beverage type on the Ra values of the resin composites (p > 0.05).

CONCLUSIONS

No correlation was found between color stability and 3D surface topography of the resin composites. Color stability of resin composites may be affected by soft beverages.

Effect of Cigarette Smoke on Surface Roughness of Different Denture Base Materials

BACKGROUND

Surface roughness is an important property of denture bases since denture bases are in contact with oral tissues and a rough surface may affect tissues health due to microorganism accumulation. Therefore, the effect of cigarette smoke on the surface roughness of two commercially available denture base materials was evaluated to emphasize which type has superior properties for clinical use.

MATERIALS AND METHODS

A total numbers of 40 specimens were constructed from two commercially available denture base materials; heat-cured PMMA and visible light cured UDMA resins (20 for each). The specimens for each type were randomly divided into: Group I: Heat cured resin control group; Group II: Heat cured acrylic resin specimens exposed to cigarette smoking; Group III: Light cured resin control group; Group IV: Light cured resin specimens exposed to cigarette smoking. The control groups used for immersion in distilled water and the smoke test groups used for exposure to cigarette smoking. The smoke test groups specimens were exposed to smoking in a custom made smoking chamber by using 20 cigarettes for each specimen. The surface roughness was measured by using Pocket SurfPS1 profilometer and the measurements considered as the difference between the initial and final roughness measured before and after smoking.

RESULTS

The t-test for paired observation of test specimens after exposure to smoking was indicated significant change in surface roughness for Group II (p< 0.05) but has no significance with Group IV. Otherwise, there were no significant differences with control groups (Group I and III).

CONCLUSION

The surface roughness of the dentures constructed from heat cured acrylic resin had been increased after exposure to cigarette smoke but had no impact on the dentures constructed from visible light cured resin.

Effects of cigarette smoke and denture cleaners on the surface roughness and color stability of different denture teeth

STATEMENT OF PROBLEM

Denture teeth have the most effect on the esthetics of complete dentures. However, extrinsic factors can change their roughness and color.

PURPOSE

The purpose of this study was to investigate the effects of smoking and denture cleaners on the roughness and color (CIE [Commission International de I'Eclairage] L*a*b*) of denture teeth.

MATERIAL AND METHODS

Maxillary central incisors made of acrylic resin, high-strength acrylic resin, and porcelain (Acrylux, SR, Orthosit PE-O, and Enta) were divided into 4 groups (n=10): control, denture cleaner, cigarette smoke, and cigarette smoke and denture cleaner. The dental cleaner group and cigarette smoke and dental cleaner group were immersed in denture cleaner (Protefix; Queisser Pharma) for 15 minutes; the cigarette smoke group and cigarette smoke and dental cleaner group were exposed to smoke from 20 cigarettes for 10 minutes per cigarette. The roughness was measured with a profilometer, and the color was measured with a colorimeter. The CIE L*a*b* values were recorded. The data were analyzed with a 3-way ANOVA and the Fisher least significant difference test (α=.05).

RESULTS

The roughness of Acrylux, SR Orthosit PE-O (P<.001), and Enta (P<.01) was significantly higher in the cigarette smoke group and dental cleaner group than in the control group. Immersion in denture cleaner after exposure to cigarette smoke decreased the roughness of Acrylux, SR Orthosit PE-O (P<.001), and Enta (P<.01). The greatest color change (7.94) was observed in Acrylux in the cigarette smoke group, whereas the smallest color change (0.24) was in Enta in the control group. The color change of all of the teeth in the cigarette smoke group decreased after exposure to denture cleaner (P<.05). The L* decreased, and the a* and b* increased after exposure to smoke (P<.05).

CONCLUSIONS

Smoking and denture cleaner increased the roughness and discolored the teeth, whereas denture cleaners after exposure to smoke decreased the roughness.