Staining Susceptibility Research Articles

Effect of swimming pool water on staining susceptibility of various restorative materials

Effect of swimming pool water on staining susceptibility of various restorative materials

Effects of two dentifrices on the surface properties and staining susceptibility of polymer-based materials.

This study examined the effect of whitening and abrasive regular dentifrices on the surface characteristics and stain susceptibility of polymer-based CAD-CAM blocks subjected to artificial toothbrushing abrasion (TB). Two resin composite blocks [CeraSmart (CS) and Grandio Blocs (GB)], one polymer-infiltrated ceramic [Vita Enamic (VE)], and one direct resin composite [GrandioSO (RC)] were used to produce 60 specimens. The baseline mass, gloss, roughness, Vickers hardness (Hv), and color were measured after 7 days of water storage. The specimens were then separated into three TB treatment groups (n = 5): water control (C), regular daily dentifrice (R), and whitening dentifrice (W). Measurements were repeated post-TB (20,000 cycles). All specimens were immersed in coffee, and the CIE ΔE00 was measured after 1, 7, and 14 days. Two-way, one-way ANOVA, and Tukey's post hoc tests were performed to determine any significant differences between the materials and TB groups. To determine the stain resistance, repeated measures of ANOVA, one-way ANOVA, and Tukey's post hoc tests were used (α = 0.05). The R and W mass changes were minimal (-3.77 to 3.16g%). W reduced the gloss of all the materials by 12.6%-65%. All materials in W were slightly rougher (Ra, 0.107-0.144 μm) than those in R (Ra, 0.049-0.072 μm). The ΔE00 ranged from 0.6 to 1.6 in W and 0.4 to 1.4 in R. VE was the hardest material at baseline (Hv = 362), whereas brushing and staining lowered Hv in all TB groups (282.8-300.6). After brushing in W, VE, and RC were more susceptible to coffee stains than were CS and GB. The whitening dentifrice roughened CAD-CAM specimens, reducing gloss, yet lightened some materials. Polymer-infiltrated ceramic and direct resin composite specimens brushed with abrasive regular or whitening dentifrice resulted in more intense staining than the CAD-CAM resin composites.

3D-printed intracoronal restorations, occlusal and laminate veneers: Clinical relevance, properties, and behavior compared to milled restorations; a systematic review and meta-analysis.

To assess the feasibility of producing 3D-printed intracoronal restorations, thin and ultrathin veneers, and to compare their mechanical behavior, accuracy, biological, and stain susceptibility to the currently applied milled restorations. The databases were comprehensively searched for relevant records up to January 2024 without language restrictions. All studies that assessed 3D-printed partial coverage restorations including inlays, onlays, laminate, and occlusal veneers were retrieved. The web search yielded a total of 1142 records, with 8 additional records added from websites at a later stage. Only 17 records were ultimately included in the review. The included records compared 3D-printed; alumina-based- and zirconia ceramics, lithium disilicate ceramics, polymer infiltrated ceramics, polyetheretherketone (PEEK), resin composites, and acrylic resins to their CNC milled analogs. The pooled data indicated that it is possible to produce ultrathin restorations with a thickness of less than 0.2 mm. 3D-printed laminate veneers and intracoronal restorations exhibited superior trueness, as well as better marginal and internal fit compared to milled restorations (p < 0.05). However, it should be noted that the choice of materials and preparation design may influence these outcomes. In terms of cost, the initial investment and production expenses associated with 3D printing were significantly lower than those of CNC milling technology. Additionally, 3D printing was also shown to be more time-efficient. Using additive manufacturing technology to produce restorations with a thickness ranging from 0.1 to 0.2 mm is indeed feasible. The high accuracy of these restorations, contributes to their ability to resist caries progression, surpassing the minimum clinical threshold load of failure by a significant margin and reliable adhesion. However, before 3D-printed resin restorations can be widely adopted for clinical applications, further improvements are needed, particularly in terms of reducing their susceptibility to stains. 3D-printed intracoronal restorations and veneers are more time and cost-efficient, more accurate, and could provide a considerable alternative to the currently applied CNC milling. Some limitations still accompany the resin materials, but this could be overcome by further development of the materials and printing technology.

Evaluation of Enamel Staining Susceptibility after Using Three Kinds of Orthodontic Adhesives and Four Different Clean-Up Techniques

Background: The present study tried to find the proper bonding and debonding technique to preserve the natural enamel surface and avoid its discoloration. Methods: Sixty newly extracted human premolars were randomly divided into three groups, and three orthodontic adhesives were applied to bond the brackets: chemically cured System 1 Plus adhesive (Ormco, USA) (CC), light-cured resin (Transbond XT, 3Munitek, USA) (LC), and resin-modified glass ionomer cement (Fuji Japan) (GI). The specimens were immersed in black tea for one week and debonded, and four prophylactic methods were applied to remove residual resin: 1) tungsten carbide bur (TC), 2) tungsten carbide bur + Sof-Lex polisher (TC + SL), 3) tungsten carbide bur + One Gloss Polisher (TC + OG), and 4) tungsten carbide bur + Po-Go polisher (TC + PG). The enamel color was measured according to the CIE standard system (Commission Internationale de l’Eclairage) by Konica Minolta CS Spectroradiometer equipment twice: 1) natural enamel color before bonding and 2) after bonding, staining, debonding, and polishing. The ΔE value is the tooth discoloration, which is measured from the mean Δa*, Δb*, and ΔL* values using the following formula ΔE = [(ΔL*)2 + (Δa*)2 + (Δb*)2]1/2 for each group. Then, it was statistically analyzed using a t-test. Results and Conclusions: Regarding adhesive materials, CC adhesive showed higher discoloration than LC in all the polishing methods. The lowest discoloration was observed in GI. The highest ΔE* values were obtained using TC only, which was deemed insufficient to remove the residual adhesives. Applying TC + Sof-Lex and TC + PoGo equally enhanced the results; therefore, they were the best polishing methods.

Comparative Research Regarding the Hydrophilic Extractives Content in Turkey Oak and Sessile Oak Wood and Their Related Staining Susceptibility by Reaction with Iron

The paper presents the experimental results concerning the amount of extractable substances and the color changes determined by the reaction of the tannins contained in wood with iron. Tests were performed comparatively with sapwood and heartwood samples of two Quercus species, namely Turkey oak (Quercus cerris L.) and sessile oak (Quercus petraea (Matt.) Liebl.). The findings show that Turkey oak sapwood has an unexpectedly high amount of extractable substances, higher than the heartwood of the same species. This result was obtained with three extraction methods (cold water, hot water, and NaOH 1% solution). The FTIR investigation of the extracts impregnated on quantitative filter paper seems to confirm these results. Visual assessment and color measurements after applying FeCl3 highlight that both oak species are prone to staining in contact with iron due to their tannin content. The values of the total color difference between the state and after the reaction with FeCl3, lower fer for Turkey oak compared to sessile oak, correlate with a lower extractive content of this wood species.

Staining Susceptibility of Microhybrid and Nanohybrid Composites on Exposure to Different Color Solutions

Composite discoloration is considered one of the most significant disadvantages of dental restorations. The purpose of our study was to assess the color susceptibility of two esthetic composite filling materials, microhybrid composite (ValuxTM Plus) and nanohybrid composite (FiltekTM Z250 XT), to different solutions and compare the results among different measuring methods (Intraoral scanner, Easyshade spectrophotometer, and Vita classical shade guide). A total of 100 specimens were fabricated in this experimental study. Each sample was soaked in either Coca-Cola, orange juice, tea, coffee, or distilled water for 30 days. Color measurement was performed using the spectrophotometer, IOS 3Shape Trios, and Vita classical shade guide. L*a*b* values were recorded to determine the color changing (ΔE00). The significance level was p &lt; 0.05. All samples showed clinically visible color changes after immersion in coffee, tea, orange juice, and Coca-Cola. The nanohybrid composite showed high color change when placed in tea (ΔE00 = 12.5) measured by the Intraoral scanner, spectrophotometer (ΔE00 = 23.21), and by Vita classical shade guide (ΔE00 = 25). Less color discoloration was perceptible in the microhybrid composite when immersed in Coca-Cola (ΔE00 = 1.78) measured by spectrophotometer, intraoral scanner (ΔE00 = 2.85), and measured by Vita classical shade (ΔE00 = 3.2). The results showed that measurements with the spectrophotometer and Vita classical shade guide were correlated. The results were analyzed using the chi-square and Wilcoxon signed-rank tests, and there was a significant difference (p &lt; 0.001) in both composite resins for all the solutions, with microhybrid being more color stable. Microhybrid composite had more color stability than nanohybrid composite, especially when immersed in tea and coffee. The spectrophotometer with Vita classical shade guide showed better interrater agreement than with the intraoral scanner.

Effect of Different Mouthwashes on Stain Susceptibility of Resin Composite in Contact with Beverages.

Objectives: This study aimed to investigate the effect of common mouthwashes on the color change of a nanohybrid composite and its further stain susceptibility to Coke and coffee. Materials and Methods: One hundred and fifty composite discs were prepared and initial color values were measured using a spectrophotometer. The specimens were grouped based on the 24h exposure to common mouthwashes including Listerine, chlorhexidine, two types of fluoride mouthwashes (alcohol free and alcohol containing) as well as distilled water as control (N=30). The color change (ΔE1) values were calculated to show the amount of color change caused by mouthwashes. Subsequently, the specimens in each group were subdivided and immersed in the secondary colorant solution (coffee, Coke and, distilled water) for seven days. The total color change (ΔE total) values were obtained to show the stain susceptibility. Statistical analysis was conducted using ANOVA and Tukey's post hoc test. A P-value less than 0.05 was considered statistically significant. Results: The calculated ΔE1 of resin composite was significantly higher for all mouthwash groups than that of the control group; however, all were in the clinically acceptable range. Exposure to Listerine and distilled water caused more staining effects compared to other mouthwashes after immersion in secondary colorant solutions. Regardless of primary mouthwash type, coffee and distilled water caused the highest and the least total discolorations, respectively (P<0.001). Conclusion: All mouthwashes caused a clinically acceptable color change in resin composite; however, further stain susceptibility depended on the mouthwashes but was not higher than distilled water.

Effect of Simulated Annual At-home Bleaching on Susceptibility to Staining, Translucency, and Whiteness Variations of Computer-aided Design and Computer-aided Manufacturing Monolithic Materials.

The effect of annual at-home bleaching on the color, translucency, and whiteness properties of computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic materials requires investigation. The aim of the present in vitro study was to evaluate the effect of simulated annual at-home bleaching (consisting of daily applications for 10 hours a day for 14 days), for up to 3 years, on susceptibility to staining (ΔE00), translucency (ΔTP00), and whiteness (ΔWID) variations and on topography of CAD-CAM monolithic materials. Disks from the Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), and IPS e.max CAD (EMAX) were allocated as follows: 1) nonbleached or 2) bleached with 10% carbamide peroxide. After reading the CIE L*a*b* coordinates at baseline (R0), specimens were bleached or not and subsequently immersed for a 1-year simulated period in coffee before the next reading (R1). This process was repeated two more times, resulting in R2 and R3. The ΔE00, ΔTP00, and ΔWID between R1, R2, and R3 in relation to R0 were calculated. The surface topography was analyzed by scanning electron microscopy. In general, bleaching increased the staining susceptibility of all materials when compared to the nonbleached groups and that of the LU, VE, and EMAX over the years. Bleaching decreased the translucency of the VE in all years and over the years. When compared to the nonbleached groups, bleaching decreased the whiteness of the LU and EMAX and increased the whiteness of the EMP, while the VE was not affected. In the LU, the whiteness decreased over the years in both treatments, whereas the other materials were not affected with time. All materials showed progressive topographic changes over the years. The simulated annual at-home bleaching with 10% carbamide peroxide adversely affected the topography and the optical and/or colorimetric properties of the evaluated materials.

Color Stability of Polymer-Based Composite CAD/CAM Blocks: A Systematic Review.

This systematic review aims to evaluate the color stability of resin composite CAD/CAM blocks (CCB) when submitted to staining solutions. A systematic search was performed on different databases (Embase, Medline, Scopus, Web of Science). Search terms were: 'polymer infiltrated', 'polymer-based', 'resin nanoceramic', 'resin ceramic', 'hybrid composite', 'hybrid ceramic', 'composite ceramic', 'resin infiltrated', 'CAD-CAM', 'CAD/CAM', 'color stability', 'staining', 'staining susceptibility', 'color change', 'color difference'. in vitro articles published in the English language until 18 September 2022 without initial time restriction evaluating the color stability of CCB when submitted to staining solutions. studies investigating color change induced by smoke or whitening treatments; studies not including a clinical evaluation of the results using the thresholds for color perceptibility and acceptability. Risk of bias assessment using the QUIN tool. Out of the 378 initially retrieved articles, 19 were included in this review. They investigated 17 different CCBs and different artificial staining by liquid protocols, including coffee, red wine, tea, and cola. CCBs exceeded clinical acceptability thresholds for color shift in 18 out of 19 studies, with a significantly higher color stability than conventional hybrid resin-based composites (RBCs), and a significantly lower color stability than ceramic materials. The identified differences in CCBs in color stability can be attributed to the material's composition, but also to the heterogeneity of staining procedures. Interpretation and clinical implication: Clinicians should be aware that, although to a lower degree when compared to RBCs used in direct or indirect procedures, CCBs undergo color changes to a higher degree in comparison to ceramic materials.

Effect of microabrasion on the staining susceptibility of enamel: An in vitro study.

Background. Enamel microabrasion can eliminate enamel irregularities and discoloration. This study evaluated the staining susceptibility of enamel after microabrasion using different clinical protocols. Methods. A total of 210 extracted bovine incisors were used in this study. The teeth were randomly divided into five groups of 42 teeth each (n=42), including group 1: control (no treatment), group 2: microabrasion, group 3: microabrasion + fluoride polishing, group 4: macroabrasion (fine-grit diamond bur) + microabrasion, and group 5: macroabrasion (finegrit diamond bur) + microabrasion + fluoride polishing. The groups were then randomly divided into two subgroups for discoloration procedures: coffee and distilled water (n=21). A spectrophotometric evaluation was carried out at baseline and on the 1st, 7th, 14th, and 28th days of the staining period. Statistical analyses were performed using repeated-measures ANOVA and the post hoc Bonferroni test at a significance level of 0.05. Results. The greatest color change was observed in group 2 specimens, which were immersed in coffee solutions. The color change values for groups 3, 4, and 5 specimens, which were immersed in distilled water, were higher than those in group 1 specimens (P<0.05). The fluoride polishing + enamel microabrasion treatment groups (groups 3 and 5) exhibited greater resistance to color changes than the matched non-fluoride-polished groups (groups 2 and 4) (P<0.05). Conclusions. The teeth that underwent enamel microabrasion treatment and were polished with fluoride gel became more resistant to color changes. Our findings confirm that enamel microabrasion treatment is a conservative method for localized discoloration.

Staining susceptibility of dental composite resins with various nano-filler technologies

Background: Discoloration of dental composite restoration is a common problem that usually results in refurbishing or replacement or even removal of the restoration. Objective: The purpose of this study was to evaluate the color stability of polished composite resin material with different filler technologies. Methodology: Three composites were studied; Filtek™ Z350 XT (3M, ESPE, St. Paul, USA) [Group-I] that has nano-cluster filler particles, Brilliant EverGlow™ (Coltene/Whaledent® AG, Altstatten, Switzerland) [Group-II] which consists of submicron barium glass fillers and pre-polymerized fillers and Ceram.X® Sphere TEC™ (Dentsply, Konstanz, Germany) [Group-III] with advanced granulated filler technology composite. Twenty standardized composite discs were prepared with each composite resin, and it was polished with Sof-Lex disks (3M, ESPE, St. Paul, USA). The baseline color was then recorded using a spectrophotometer (X-Rite PANTONE® iPro-2, Michigan). Eight samples from each group were then subdivided and immersed into freshly prepared solutions of turmeric, coffee, and four samples into distilled water for a total period of 3 hours/day for 30 days. Following this, the color was again recorded. Statistical analysis: The change in color (ΔE) was calculated, and the data obtained were subjected to Kruskal Wallis and Mann Whitney test. Results: A significant difference was seen between the staining characteristics of Group-III and Group-I (p&amp;lt;0.05). The mean color change in the values was highest in Ceram.X that was clinically unacceptable (ΔE&amp;gt;3.3). Conclusion: Though all composites revealed color changes after their immersion into the staining solutions, the amount of stain varied based on their constituents and filler characteristics.

Effect of different surface treatments on the microhardness and colour change of artificial enamel lesions.

To investigate the effect of three different surface treatments on the microhardness and colour change of artificial enamel lesions. One hundred bovine teeth were randomly assigned into four groups. Artificial enamel lesions were created using demineralizing solution for all groups except the sound enamel group. Different surface treatments were then performed G1: resin-infiltrant; G2: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP); G3: artificial saliva; G4: Sound Enamel. Each group was subdivided into three subgroups, where each subgroup was subjected to a different testing method. Subgroup 1: surface microhardness; subgroup 2: cross-sectional microhardness; subgroup 3: colour measurement. Statistical analysis was performed by ANOVA, followed by Tukey's post hoc test. Sound enamel group recorded the highest surface and cross-sectional microhardness results. No significant difference was found between the resin-infiltrant group and CPP-ACP regarding surface and cross-sectional microhardness at different lesion depths. Resin-infiltrant group showed the least colour change (∆E) results compared to the other groups. Resin-infiltrant can effectively enhance surface microhardness and enamel resistance to demineralization, additionally, reduces the staining susceptibility of white spot lesions (WSLs) after treatment. CPP-ACP application for 4 weeks seems to improve surface microhardness; however, has a limited effect in resisting staining of WSLs after treatment. © 2022 Australian Dental Association.

Long-term effect of gastric juice alternating with brushing on the surface roughness, topography, and staining susceptibility of CAD-CAM monolithic materials

Statement of problemStudies on the behavior of computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic materials subjected to gastric juice alternating with brushing—as occurs in patients with bulimia nervosa—are lacking. PurposeThe purpose of this in vitro study was to evaluate, over a simulated 5-year period, the effect of gastric juice alternating with brushing on the roughness, topography, and staining susceptibility of CAD-CAM monolithic materials. Material and methodsDisks of Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), IPS e.max CAD (EMAX), and Vita Suprinity (VS) were randomly allocated to artificial saliva+brushing or gastric juice+brushing groups, simulating 1, 3, and 5 years of clinical function. The roughness (Sa) and topography were evaluated at baseline (T0) and at each simulated year. For the staining susceptibility (ΔE00), the CIELab color coordinates were registered at baseline, and, at the end of the fifth simulated year, the specimens were immersed in deionized water, coffee, or cola before the second reading. Roughness data were submitted to mixed repeated-measures ANOVA and Bonferroni, and the staining susceptibility data were analyzed by 3-way ANOVA and the Games-Howell test (α=.05). ResultsThe gastric juice+brushing led to higher roughness than artificial saliva+brushing only in the VE at T3 and T5 (P<.01). In both treatments, the LU and VE showed topography changes and an increase in roughness over time (P<.001), in addition to higher roughness than the other materials (P<.001). The staining susceptibility of the materials to each staining solution was not affected by the treatment (P>.05). The LU and VS groups were more stained by coffee (P<.001), while the VE and EMP groups were more stained by cola (P≤.016), except for the EMP in the gastric juice+brushing, where no significant difference was found between cola and coffee (P>.05). The EMAX was imperceptibly affected by the 3 solutions. ConclusionsConcerning roughness and topography, the LU and VE were the most affected by both treatments. The staining susceptibility of the materials was not affected by the treatment.

Stain Susceptibility of 3D-Printed Nanohybrid Composite Restorative Material and the Efficacy of Different Stain Removal Techniques: An In Vitro Study.

Recent burgeoning development in material science has introduced a 3D-printable, nanohybrid composite resin restorative material. However, its performance has not yet been investigated. This study evaluates the stain susceptibility and efficacy of different stain removal techniques. A total of 120 labial veneers were fabricated using milling (n = 60) and SLA 3D-printing (n = 60). Based on the immersion media: coffee, tea and artificial saliva, each group was divided into three sub-groups (n = 20). Stain susceptibility was evaluated by calculating color difference (∆E00) at 12 and 24 days using a spectrophotometer against black and white backgrounds. Collected data were analyzed with ANOVA and Tukey’s post hoc test (p < 0.05). A significant interaction effect was found between the staining mediums and fabrication methods in both black and white backgrounds (p < 0.001). 3D-printed restorations showed significantly higher stain susceptibility than milled restorations (p < 0.001). Prolonged immersion time increased the color difference in both groups. In-office bleaching was more effective in stain removal in both 3D-printed and milled restoration groups. The susceptibility of the presented novel 3D-printed restorative material to color changes in different immersion mediums was clinically not-acceptable. The clinicians might expect the need to replace the restoration after 1–2 years and thus, recommendation for the use of such a material as a permanent restoration cannot be made but rather as a long-term temporary restoration.

Color Stability and Staining Susceptibility of Direct Resin-Based Composites after Light-Activated In-Office Bleaching.

This study evaluated color stability and staining susceptibility of five direct resin-based composites (RBCs) subjected to light-activated in-office bleaching with 40% hydrogen peroxide (HP). The test materials included 5 RBCs, which consisted of one nano-filled, one sub-micron, one bulk-filled, and two nano-hybrid RBC types. Ten disc-shaped specimens of each RBC were fabricated and divided into bleaching (BLE) and non-bleaching (CON) groups (n = 5 for each group). Specimens were then immersed in red wine solution over 4 h. A spectrophotometer was used to obtain Commission Internationale de l’Eclairage (CIE) L*a*b* parameters for each of the following periods tested: before bleaching (TBA), after bleaching (TBL), and after staining (TST). Color stability and staining susceptibility were evaluated using two metrics, CIEDE2000 color differences (ΔE00) and whiteness variations using the whiteness index (ΔWID). Data were analyzed using repeated measures two-way analysis of variance (ANOVA) (α = 0.05). Statistically significant and clinically unaccepted ΔE00 and ΔWID were observed for all tested specimens between TBA and TBL. The nano-hybrid type RBCs showed the highest discoloration among materials after bleaching treatment. The BLE group exhibited significantly higher ΔE00 and ΔWID than the CON group for all the tested RBCs between TBA and TST. The sub-micron type RBC showed the highest discoloration among materials after immersion in the red wine. Conclusion. The light-activated in-office bleaching with 40% HP’s influences on color and whiteness index were material-dependent. The use of bleaching treatment also increased the susceptibility to red wine for all RBCs.

Effect of In-office Bleaching on Color, Translucency, and Whiteness Variations in CAD-CAM Monolithic Materials.

Little is known about the impact of bleaching on the optical properties of computer-aided design and computer-aided manufactured (CAD-CAM) monolithic materials. The aim of the present study was to evaluate the effect of one session of in-office bleaching on stain removal, staining susceptibility, translucency, and whiteness variations of CAD-CAM monolithic materials. Disks were fabricated from Lava Ultimate (LU), Vita Enamic (VE), Vita Suprinity (VS), and IPS e.max CAD (IPS). A spectrophotometer was used to register Commission Internationale de l'Eclairage L*a*b* coordinates. For stain removal, 80 specimens from each material were assessed at baseline (R0) and after immersion in deionized water or coffee for 36.5 days followed or not by bleaching with 40% hydrogen peroxide (R1). For staining susceptibility, 80 specimens from each material were analyzed at baseline (R0'), and after having been bleached or not and immersed in deionized water or coffee (R1'). Both analyses were calculated as the color difference (ΔE00) between R1-R0 and R1'-R0', respectively. Differences in translucency (ΔTP00) and whiteness (ΔWID) between R1-R0 and R1'-R0' were also calculated. Data were analyzed by three-way ANOVA and the Games-Howell post hoc test (α=0.05). Clinical significance was based on 50%:50% perceptibility and acceptability thresholds for ΔE00, ΔTP00 and ΔWID, respectively. Surfaces were analyzed by scanning electron microscopy. Coffee increased ΔE00 in LU, VE, and VS, and decreased their translucency and whiteness, whereas the IPS had only its whiteness affected. Bleaching after immersion in coffee decreased ΔE00 in LU and VE, and increased translucency and whiteness of LU, VE, and VS. No effect was observed on IPS. Bleaching before immersion in coffee decreased translucency of LU, but within the acceptable interval, while VE exhibited lower ΔE00, and became more translucent and less dark. Both VS and IPS were not affected. One session of in-office bleaching benefited optical properties of the previously stained LU, VE, and VS, without increasing their susceptibility to staining or adversely providing clinically unacceptable variations in their translucency and whiteness. All variations exhibited by the IPS were below the perceptible threshold.

Evaluation of Stain Susceptibility of Different CAD/CAM Blocks After Immersion in Coffee

Aim: Color stability is gaining more importance today due to majority of patients are seeking color matching restorations. However, there is still lack of information on staining and changes in translucency of recent CAD/CAM block materials. The goal of the current study was to evaluate the discoloration susceptibility, translucency change, water solubility, and water sorption of different CAD/CAM materials after one-month of immersion in coffee. Material and Methods: Four CAD/CAM block materials and one conventional composite resin were examined. The CIELab values of CAD/CAM materials were determined using a clinical spectrophotometer on black and white backgrounds. The color changes and translucency differences were calculated after immersion in coffee or distilled water for one month (n=6). Water solubility and sorption were also determined according to the ISO 4049:2009 (n=6). The data were calculated by 2-way ANOVA and Tukey’s pair-wise comparisons (α=0.05). Results: Color changes of the CAD/CAM materials tested ranged from 1.5 to 7.3, and translucency reduced. The highest color change was observed in nanocomposite resin (7.3), whereas the lowest color change was observed in feldspathic porcelain (1.5) after storing in coffee for a month. There was no significant difference among the polymer-based CAD/CAM materials. No correlation was determined between color changes and water sorption/solubility. Conclusion: All materials except feldspar ceramic showed a discoloration exceeding the clinically acceptable threshold level (2.7) after being stored in coffee for one month. The highest color change was observed in nanocomposite resin material.

The effect of staining and bleaching on the color of two different types of composite restoration.

BackgroundLong term success of composite restorations depends greatly on their color stability and esthetic appearance. This study aimed to assess the effects of commonly consumed beverage and bleaching on the color of composite restoration. Material and MethodsTwo resin composite were used Filtek™ Z350 XT (3M/ESPE) and Briliant EverGlow (Coltene). Fifteen discs were made from each resin composite then baseline color measurements were made. The specimens divided into 3 groups (n=5) according to the storage solution. The storage solutions that used in this study are distilled water, tea and coffee. The specimens were stored in the solutions for 3h/day for 40 days and then second color measurements were done. Specimens were bleached by using of 40% H2O2 Opalescence boost. Then the specimens color were measured for the third time. For measuring color change CIE L* a* b* system was used. The results were statistically analyzed using Two-way analysis of variance (ANOVA) and Bonferroni tests. Level of significance was set at p < 0.05. ResultsIn all groups there were a significant color change (∆E>3.3). The discs that were made from Filtek™ Z350 XT (3M/ESPE) and immersed in coffee show the highest color change whereas the discs that were made from Briliant EverGlow and stored in distilled water show the least color change. Significant improvements in the color of specimens were demonstrated after bleaching, however bleaching couldn’t restore the composite color to clinically acceptable level (∆E<3.3). ConclusionsBoth tested materials were susceptible to staining in the three-staining solution; Filtek™ Z350 XT showed more staining susceptibility than Briliant EverGlow. In office bleaching reverse some of the effect of staining from the surface of the composite but it couldn’t restore the composite color to its original color before staining. Key words:Staining, color change, resin composite, bleaching.

Color Stability of Artificial White Spot Lesions treated with Resin Infiltration

Objective: To evaluate the color stability of artificial white spot lesions treated with three different surface treatments after immersion in staining solution. Materials and Methods: An artificial white spot lesion was created in the middle of the labial surface using demineralizing solution. Sixty-five bovine teeth were randomly assigned into 5 groups (n=13) according to surface treatment. G1: Enamel submitted to demineralization only. G2: Polished Enamel. G3: Demineralized enamel treated with low-viscosity resin infiltrant. G4: Demineralized enamel treated with CPP-ACP for 1 month. G5: Demineralized enamel treated with Artificial saliva for 1 month. All specimens were then immersed in a staining solution (coffee) for 8 weeks. Color measurements, using the CIE L*a*b* system, were done immediately after treatment and after 2, 4 and 8 weeks of immersion, by Spectrophotometry. Digital photographs were also taken at each stage to a representative specimen from each group. In addition, representative specimen for each group was evaluated using Polarized Light microscope. Color change (ΔE) was analyzed by two-way mixed ANOVA. Results: Resin infiltrant group exhibited the lowest color change values at all times of measurement, followed by CPP-ACP and polished enamel, while the highest color change values were recorded in samples without treatment. Conclusion: Resin infiltrant can be considered an effective treatment in masking and reducing long-term staining susceptibility of white spot lesions after treatment.

Effect of Bleaching on the Staining Susceptibility of Enamel and Composite Resin (An in Vitro Study)

Effect of Bleaching on the Staining Susceptibility of Enamel and Composite Resin (An in Vitro Study)