Baseline Color Measurements Research Articles

A comparative study of polishing systems on optical properties and surface roughness of additively manufactured and conventional resin based composites

This study aimed to compare polishing systems on color stability, surface roughness, and gloss of additively manufactured permanent and conventional resin composites. Totally 250 disc specimens (6 mm*2 mm) were prepared from resin-based materials [G-ænial Posterior (GP), Clearfil Majesty Esthetic (CME), SonicFill-2 (SF), Tescera (Tes), and Crowntec (CT)]. Following baseline color (ΔE00), gloss (GU), and surface roughness (Ra) measurements, the specimens were randomly divided into 5 groups (n = 10/group) according to polishing systems: Control (mylar strips); OneGloss; OneGloss + Platina Hi-Gloss; OptiDisc; and OptiDisc + Platina Hi-Gloss. Specimens were immersed in coffee for 144 h following polishing. ΔE00, GU, and Ra measurements were repeated. Atomic force microscopy images were taken in all groups. Spearman’s rho correlation coefficient, Robust ANOVA, and Bonferroni correction were used for statistical analysis. Significance level was taken as p < 0.050. Significant differences in ΔE00 values were found among resin-based materials, polishing systems, and their interactions (p < 0.001,p < 0.01, and p = 0.001). Regardless of polishing system, the lowest ΔE00 values were observed in CT, while lowest gloss (GU) values were found in Tes. The lowest surface roughness (Ra) values were detected at OptiDisc group (p < 0.001). A single type of polishing system may not be sufficient to achieve optimal results in resin-based materials.

Assessing the Color Stability of Polymethyl Methacrylate (PMMA) Dental Restorations Polished With a Novel Polishing Agent Derived From Pulverized Old Alginate Impressions.

Interim restorations are essential in restorative dentistry, serving as temporary solutions until permanent restorations can be placed. Polymethyl methacrylate (PMMA) is a promising solution for customizing teeth for removable dentures to match the exact requirements of patients. The color stability of these restorations is critical for patient satisfaction. PMMAis a widely used material for interim restorations due to its favorable properties. The study compares the color stability of PMMA interim restorations polished using traditional pumice versus Algishine, a novel polishing agent derived from pulverized old alginate impressions. The 3-D design software Geomagic Design X (3D Systems, Rock Hill, CA) created a standard tessellation language file of 2-cm radius circles. Sixty PMMA samples were milled and divided into two groups of 30 each. Group A samples were polished using pumice, while group B samples were polished with Algishine. Baseline color measurements were taken using a spectrophotometer (VITA Easyshade V, VITA Zahnfabrik, Bad Säckingen, Germany). The samples were then subjected to staining with coffee, tea, and red wine solutions for 30 days, simulating oral conditions. Post-staining color measurements were taken, and color changes (ΔE) were calculated at the seven-day (t1) and one-month (t2) mark. The Shapiro-Wilk test assessed normality, followed by a two-way ANOVA testto compare color change values at different time points. At t1 (seven days), there were no significant differences between groups A and B in the coffee and tea staining groups. However, significant differences were observed in red wine staining, with group B exhibiting lower ΔE values (0.14 ± 0.067) compared to group A (0.38 ± 0.076) (p < 0.01). At t2 (30 days), significant differences were noted in all staining groups. Group B consistently showed lower ΔE values: coffee (0.125 ± 0.084 vs. 0.236 ± 0.015, p < 0.01), tea (0.254 ± 0.087 vs. 0.391 ± 0.015, p < 0.01), and red wine (1.174 ± 0.045 vs. 1.309 ± 0.074, p < 0.01), indicating superior resistance to staining compared to group A. The results suggest that Algishine is more effective than pumice in maintaining the color stability of PMMA interim restorations. The novel polishing agent derived from old alginate impressions enhances esthetic longevity and provides an eco-friendly solution for recycling dental material waste. Algishine performs superiorly in preserving the color of PMMA interim restorations against common staining agents. Its application can potentially improve patient satisfaction and contribute to sustainable dental practices.

Evaluation of Color Stability of Different Esthetic Restorative Materials with Whitening Dentifrices

Introduction: Color stability and surface roughness are important factors affecting the longevity of any restorative material, as a rough surface structure can lead to staining and discoloration. Aim: The aim of this study was to evaluate the effects of application of two over-the-counter whitening toothpastes (Colgate Optic White and Close-up) on the color stability of different esthetic restorative materials (resin composite and conventional glass-ionomer). Materials and Methods: Using Mylar strips, 120 specimens were created from each restorative material (resin composite and conventional glass-ionomer). Baseline color measurement was done. This was followed by brushing the specimens according to the groups were brushed with the different whitening toothpastes. Before measuring color, the samples were washed. Results: A significant color change was observed between the two restorative materials. The color change was significantly higher with Colgate Optic White than Close-up toothpaste. Furthermore, composite material showed higher color stability than glass-ionomer cement (GIC). Conclusion: When used for 2 min twice day for 15 days, the whitening toothpastes Colgate Optic White and Close UP do create noticeable changes in the color. Furthermore, composites showed higher favorability for color stability than GIC.

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.

Color match evaluation using instrumental method for three single-shade resin composites before and after in-office bleaching

Abstract The aim of this study is to evaluate the effect of an office bleaching agent on the color of various single-shade resin composites. Three single-shade resin composites were tested in this study. Thirty disk-shaped specimens were prepared with a diameter of 10 mm and a height of 1 mm, and they were divided into three groups (n = 10). After color measurements, 40% hydrogen peroxide containing bleaching agent gel was applied to all the specimens. Baseline and final color measurements were performed using a clinical spectrophotometer. Statistical analyses were performed. All bleached specimens had clinically incomprehensible color changes (ΔE &lt; 3.3). Comparisons for single-shade composites revealed no statistically significant color difference between groups. With the limitation of this study in mind, color changes in single-shade resin-composites after office bleaching were found to be clinically acceptable. It may be appropriate to use single-shade composites that shorten the in-chair clinical time by facilitating shade selection.

The Effect of Whitening Mouthrinses on the Color Stability of a BIS-GMA Free Composite Resin: An Invitro Study

Purpose: Recently, many whitening mouthrinses have appeared on the market with different ingredients due to their ease of use and low costs. Whether these mouthrinses change the color of composite resins has been a matter of curiosity. The aim of this study was to investigate the effect of whitening mouthrinses with different chemical structures on the color stability of a Bis-GMA free resin composite. Materials&amp;amp;methods: Seventy disc-shaped specimens (8 mm x 2 mm) were prepared from a Bis-GMA free composite resin and randomly divided into seven groups, according to the mouthrinses (n=10): Listerine Advanced White, Colgate Optic White, Perfect White Black, Crest 3D White, Pasta Del Capitano, Oral B 3D White Luxe. The control group used in the study was distilled water. After the baseline color measurement values were recorded with a spectrophotometer (Vita Easy Shade V, Vita Zahnfabrik, Bad Sackingen, Germany). At the end of the keeping period, color measurements were repeated and changes in color values were calculated (ΔEab) using the CIE L*a*b* color system. Statistical analysis of the values obtained was made according to Kruskal Wallis test (p &amp;lt;0.05). Results: All samples demonstrated color changes within clinically acceptable limits in whitening mouthrinses after immersion (ΔEab = 1.005 - 2.062). There was no statistically significant difference among the whitening mouthrinses (p &amp;lt;0.05). Conclusion: It may be concluded that the whitening mouthrinses used in this study did not cause a significant color change during our holding time in Bis-GMA free composite resin.

Water Sorption, Solubility and Color Stability of Different Bulk-Fill Restorative Materials

Objectives: The aim of this study was to evaluate the color stability, water sorption and solubility of recent bulk-fill restorative materials. Materials and Methods: Seventy disc shaped specimens (height:1mm, diameter:15mm) were prepared with a micro-hybrid composite resin (Z250; Filtek Z250, 3M ESPE), two resin-based bulk-fill (Filtek One Bulk Fill, 3M ESPE and EBF; Estelite Bulk-Fill Flow, Tokuyama Dental), glass ionomer-based restorative (Equia FF; Equia Forte Fil, GC Dental), self-cure and light-cure alkasite (CN; Cention N, Ivoclar Vivadent) and indirect composite resin (Gradia P; Gradia Plus, GC Dental) (n=10). Baseline color measurements were performed and mass of the samples (m1) were noted. Color measurements were repeated after 24 h and 28 days immersion of the specimens in water. After the 28-days immersion, mass was noted as m2. Specimens were kept in desiccators and final mass (m3) were recorded. The color change (ΔE00) water absorption (WSP) and water solubility (WSL) of the specimens were calculated. Results: After 28-days immersion, Gradia P showed significantly lower water sorption than EBF and Equia FF groups (p&amp;lt;0.05). Light-cured and self-cured CN groups showed similar sorption with resin composite groups (p&amp;gt;0.05). The lowest solubility was observed in Z250and Gradia P. The lowest (ΔE00) was observed in self-cured CN group (p&amp;lt;0.05) and Gradia P showed the highest ΔE00. Conclusions: Light-cured and self-cured CN groups demonstrated similar sorption to the conventional composite resin and indirect composite resin. Self-cured CN demonstrated higher water solubility than composite resins. Restorative materials showed moderately unacceptable color change after 28-day immersion in distilled water.

Fracture strength and color stability of direct composite veneer using different materials

Aim: The purpose of this study was to compare the fracture resistance and color stability of three different restoration materials: Nano composite, flowable composite, and Nanohybid composite.&#x0D; Materials and Methods: 45 removed human maxillary premolar teeth for orthodontic treatment were chosen. The teeth were divided into three experimental groups, each consisting of fifteen teeth: Direct composite veneers constructed of Nano - composites were employed to fix the teeth in Group A. (Z350 XT, 3M, USA). Group B: Flowable composite was used to directly veneer teeth (G-aenial Universal flo GC, Japan). Group C: Direct composite veneers made of Nanohybid composite were used to reconstruct teeth (G-aenial GC, Japan). Each tooth in groups A, B, and C had a copyplast template made prior to preparation using a 1 mm thick vacuum-pressed polyethylene plastic template. Standard preparations (intra enamel) were made for all teeth in experimental groups using ceramic veneer set burs. By injecting flowable composite via a hole formed in a copyplast template, Group B is restored. In Groups A and C, the buccal third (Bucco-palatally) of the template was filled with restorative material using a plastic tool before being positioned on the tooth and squeezed until it made contact with the unprepared tooth surface. All specimens' baseline colors were assessed using a spectrophotometer (Vita Easyshade, Ivoclar VivadentAG, Schaan, Liechtenstin). After baseline color measurement, each group of laminate veneers were subjected to immersion solutions (Tea bags, Lipton). Each specimen's color values were once again measured with the same spectrophotometer,&#x0D; &#x0D; and the color change values (ΔE) were computed. Using a universal testing equipment, the fracture strength was evaluated.

Which whitening toothpaste with different contents is more effective on color and bond strength of enamel?

To evaluate the effects of six whitening toothpastes with different whitening ingredients as follows: abrasives, polyphosphates, activated charcoal and hydrogen peroxide on the color, and shear bond strength (SBS) of enamel. Thirty-five extracted human molars were sectioned in mesiodistal direction, providing 70 enamel specimens and randomly divided into seven groups having different whitening ingredients (n=10). After baseline color measurements, the specimens were brushed three times daily for the 30 s. At the end of 2 weeks, spectrophotometric readings were repeated, and color change parameters were calculated. Then, composite cylinders were built on the enamel surfaces and the specimens were subjected to SBS test. Failure modes were determined under a stereomicroscope (×10). One specimen from each group was examined with scanning electron microscope (SEM). The data were statistically analyzed using Kruskal-Wallis, Wilcoxon signed, one-way-ANOVA (p=0.05). Clinically acceptable color change was observed in all whitening toothpastes. There were no significant differences among the groups for Δa, ΔL, ΔE00 , and ΔWID (p > 0.05). The differences among the groups were not significant regarding SBS and failure mode distributions (p > 0.05). SEM findings were in line with the SBS test and failure mode distribution results. All the tested whitening toothpastes showed similar and clinically acceptable efficacy on the color change of the enamel and led to comparable SBS values. The tested whitening toothpastes had an acceptable whitening efficacy and did not have a negative effect on the bond strength to the enamel.

12- months color stability of direct resin composite veneers in anterior teeth: Clinical trial

Background: This clinical trial aims to evaluate the color changes of direct resin composite veneer (DCV) restorations based on spectrophotometric analysis of 4 different types of resin composites between the baseline immediately after polishing and after one year of follow-up. Materials and methods: 28 patients were assessed for eligibility for participation, aged between 18 and 38 years old, who indicated for DCV restorations in anterior maxillary teeth were considered for participation in this study. In total, 25 patients who met the inclusion criteria were selected (6 males and 19 females, mean age: 20.9 at the time of restoration placement), and 3 patients were excluded. Participants were divided into four groups based on the type of composite resin used for restorations. Group 1 nanohybrid Ips Empress direct (Ivoclar Vivadent)](IPS) (13 restorations/6 patients), group 2 microfilled [Essentia (GC cooperation Japan)](ES) (14 restorations / 7 patients), group 3 supra-nano filled [ Estelite ∑ Quick (Tokuyama, Tokyo, Japan)](EQ) (17 restorations / 7 patients) and group 4 nanofill [Filtek Ultimate (3M ESPE)](FU) (13 restorations / 5 patients). Baseline Color measurements were performed with a spectrophotometer immediately after finishing and polishing (baseline), and after one year of recall, color change (ΔE) from baseline values and after one year of follow-up of DCVs were calculated according to CIELab color coordinates. For this, a silicone mold was fabricated for each patient and used as a guide for each measurement to standardize the site of the readings. Statistical analysis of the data was applied using the Kruskal-Wallis test with Dunn-Bonferroni posthoc test after controlling the distribution of data in terms of normality with the Shapiro Wilk test. Results: At the end of one year,25 participants(57restorations) were followed up. The mean ΔE of IPS, EQ, and FU composites were higher than the ES composite resin, but there was no statically significant difference between all types of composites (P&gt; 0.05). There was no statistically significant difference in the mean ΔL* between any types of composite resin (p&gt; 0.05). There was a significant change in Δa* and Δb* after a one-year recall for all the types of DCV restorations (p &lt; 0.05). Conclusion: After one year of follow-up, the spectrophotometer measurements of direct resin composite veneer restorations, it was concluded no difference between the mean ΔE of ES, IPS, FU, and EQ resin composite. ES (Microfilled hybrid) showed a lower mean ΔE value compared to the other groups. All groups of resin composite showed color changes within clinically acceptable levels after a one-year follow-up.

The effect of bleaching applications on stained bulk-fill resin composites

BackgroundThe structure of bulk-fill resin composites differs from that of their conventional counterparts, but how this difference affects the color stability of the former after staining and bleaching is unclear. Accordingly, this study was aimed at investigating color change in nine bulk-fill resin composites and one nanohybrid resin composite treated with hydrogen peroxide and carbamide peroxide after staining with tea, coffee, and red wine.MethodsEighty specimens were prepared from each resins [Clearfil Majesty Posterior (CMP), SDR flow+ (SDR), FiltekTMBulk-Fill Flowable Restorative (FBF), Reveal HD Bulk (RHD), Beautifil-Bulk Restorative (BBR), Tetric EvoCeram® Bulk Fill (TEC), SonicFill™2 (SF2), everX Posterior™ (eXP), X-tra base (XB), and Venus® Bulk Fill (VBF)]. Following baseline color measurements, the specimens were randomly divided into 4 groups according to immersion solutions and distilled water as the control. At the end of a 30-day test period, color measurements were repeated, and color change values (∆E00) were calculated. Each resin group was then divided into 2 subgroups (with 10 specimens per group) on the basis of bleaching agent (Opalescence Boost 40%, Opalescence PF 16%). Following bleaching application, ∆E00 and changes of whiteness (∆WID1 = WIDbleaching-WIDbaseline, ΔWID2 = WIDbleaching-WIDstaining) values were recorded. Two- and three-way analyses of variance and Tukey’s post hoc test were performed, with a P < 0.05 regarded as indicative of significance.ResultsAfter immersion in distilled water, tea, and red wine, the highest ΔE00 values were observed in eXP (P < 0.05). Resin materials immersed in coffee and tea exhibited statistically higher ∆E00 values than those immersed in red wine except for eXP, TEC, and FBF (P < 0.05). For eXP, the highest ∆E00 values were recorded in distilled water. For TEC and FBF, there was no statistically significant difference among the immersion solutions and distilled water (P > 0.05). For all the resins and staining beverages, no statistically significant difference in ∆WID1 and ∆WID2 values were detected between bleaching agents (P > 0.05). All the ΔWID1 values were above the whiteness perceptibility threshold.ConclusionThe bulk-fill materials were more resistant to discoloration and bleaching procedures than the conventional resin composites. Coffee and tea caused more staining than distilled water and red wine generally. The type of bleaching procedure had no effect on the whiteness of the tested materials.

Effect of Different pH Beverages on the Color Stability of Smart Monochromatic Composite

Omnichroma is a smart monochromatic material and is believed to attain the shade of the surrounding tooth structure in which it is placed. However, the color stability of this material is unknown. Therefore, this study was conducted to evaluate the effect of different pH beverages on the color stability of the Omnichroma composite and its comparison with micro-hybrid composite resin. Sixty extracted human maxillary premolars of different shades, viz. A2, A3, B2 and B3, were selected in equal numbers. A Class V cavity was prepared on the buccal and palatal sides of each tooth. After the cavity preparation, etching of the cavity was performed with 35% phosphoric acid followed by bonding. The prepared cavities were then filled with Omnichroma composite resin on the buccal side and Filtek Z250 composite on the palatal side. The baseline color measurements of all tooth samples were performed by a spectrophotometer. The teeth were then divided into three groups, the Pepsi group, coffee group and milk tea group. Five teeth from each shade, viz. A2, A3, B2 and B3, were immersed in 10-mL of Pepsi, coffee, and milk tea for 14 days. After the completion of the 14 days, the teeth were rinsed and kept in distilled water for 24 h. Finally, a spectrophotometer was used to calculate the color alteration value ΔE. Mean difference in ΔE values of the samples before and after immersion in different beverages was calculated and analysed by SPSS 25. One-way ANOVA test was applied to compare groups. Further stratification was performed using the Post-Hoc Tukeys test. Samples immersed in milk tea showed a statistically significant difference (p &lt; 0.05) in A2, A3, and B2 shades of the OM-milk tea group in comparison with the FT-milk tea group. In summary, the immersion of teeth in beverages with a different pH and colorants showed an apparent alteration in the color of both the smart monochromatic and micro-hybrid composites. Hence, the type of resin composite material should be selected wisely depending on the patient’s drinking and social habits.

Impact of two energetic drinks on color stability, surface roughness and microhardness of some ceramic and hybrid materials

Objective To evaluate the impact of two energetic drinks on color stability (CS), surface roughness (SR) and microhardness (HV) of some ceramic and hybrid materials. Materials and methods A total of 72 square-shaped samples (0.8 mm in thickness, 10 mm in width and 12 mm in length) were divided into three groups (n = 24) according to the studied materials: Celtra Duo, IPS e.max CAD/CAM and Nacera Hybrid. Each group was subdivided into three subgroups (n = 8) according to the three immersion solutions applied: artificial saliva, Hype and Power horse energetic drinks. Samples were sectioned using an Isomet 4000 (Buehler, Lake Bluff, USA) and then stored in artificial saliva for 24 h before doing the baseline color, surface roughness and microhardness measurements. For determination of color change (ΔE), a reflective spectrophotometer was used. Surface roughness (SR) testing was carried out using an optical profilometer with a built-in camera and the microhardness (HV) investigation was performed with a Microhardness Digital Tester. After 60 days of immersion in energetic drinks, these measurements for color stability, surface roughness and microhardness were repeated in the same way. Data were tabulated and analyzed using a two-way ANOVA followed by one-way ANOVA and Tukey's post-hoc test with a significance level assigned at P ≤ 0.05 for all tests. Results Statistical analysis revealed significant differences between studied groups for CS (P = 0.031), SR (P = 0.012) and HV (P = 0.028). Celtra Duo recorded the lowest color change (0.57 ± 0.09) and surface roughness (0.2499 ± 0.0033) and greatest microhardness (659.62 ± 6.10) with all immersion solutions. Nacera Hybrid material showed poorer values in all investigated properties compared to Celtra Duo and IPS e.max ceramics. For all studied materials, the greatest effect of immersion solutions on CS, SR and HV was exhibited by Power horse followed by Hype and artificial saliva. Conclusions The energetic drinks studied significantly increased SR and decreased CS and VH of Nacera Hybrid. Celtra Duo and IPS e.max CAD/CAM ceramics showed greater resistance to acidic energetic drinks compared Nacera Hybrid material. Clinical significance It is essential for the dentist to reinforce the awareness of patients regarding the risks of heavy consumption of energetic drinks. Nacera Hybrid material is a promising material but should not be used in esthetic restorations.

Spectrophotometric analysis of color stability of esthetic restorative material in chlorhexidine mouthwash: An in vitro study.

Commendable aesthetic properties of composites make it a pioneer filling material. However, discoloration of composite resin materials emerges as a major clinical problem in a long term. Aim of the study is to evaluate the color stability of nano filled and micro hybrid dental composite resin in chlorhexidine mouthwash. 20 specimens of dimension 10*2mm were prepared of A2 shade. All the prepared samples were immersed in 20 ml of distilled water in separate containers according to the group. Further incubation at 37°C for 24 h was done. After 24 h, baseline color values of each sample were recorded using a spectrophotometer. After recording the baseline color measurements, 10 specimens (random selection) from each group were placed in 20 ml of 0.2% chlorhexidine mouthwash for 24 h duration. The L*a*b* system of the Commission Internationale de l'Eclairage (CIE L*a*b* Color Scale) was used for the determination of colorimetric values of the specimens. The color change was displayed by both the samples after immersion in the mouthwash but the change was not statistically significant (0.763). ΔE value for nano filled composites is 3.25 while for the micro-hybrid composites the value is 3.56. The colorimetric values of nano filled composite resins are more stable than the micro hybrid composite due to exposure to chlorhexidine mouthwash.

Stainability of different ceramic materials against mouth rinses and effect of polishing after staining

Statement of problemMouth rinses are known to stain tooth surfaces. However, their staining effect on different ceramics after prolonged use and the effect of polishing after staining are still unclear. PurposeThe purpose of this in vitro study was to evaluate the stainability of different ceramic materials against different mouth rinses and the effect of polishing on staining. Material and methodsForty disk-shaped specimens were prepared from each material (total of 160 specimens): lithium disilicate (IPS e.max CAD), zirconia-reinforced lithium disilicate (VITA SUPRINITY PC), leucite-reinforced feldspar (GC Initial LRF), and resin matrix ceramic (CERASMART). Baseline color measurements (T0) were recorded with a clinical spectrophotometer (VITA Easyshade V). The specimens were immersed in chlorhexidine gluconate (CHX) 0.2% mouth rinse (Klorhex), (KLO) chlorhexidine gluconate 0.1% mouth rinse (Eludril) (ELU), a daily mouth rinse (LISTERINE Cool Mint) (LIS), artificial saliva (CON) continuously for 7 days (T1), 14 days (T2), and 28 days (T3). Discoloration values (ΔE) between the immersion time points (T0,T1,T2,T3) were calculated by using the following formula: ΔE= ([ΔL∗]2 + [Δa∗]2 + [Δb∗]2)1/2. After the immersion process, specimens were polished and ΔE values remeasured. The Kruskal-Wallis and Mann-Whitney U tests were performed (α=.05) and were adjusted by postanalysis Bonferroni testing. ResultsKLO caused the highest ΔE values in all groups. IPS e.max CAD had the lowest ΔE values, and CERASMART showed the highest ΔE values against all of the solutions (P<.05). However, polishing caused a decrease in the ΔE values in all groups. ConclusionsProlonged use of mouth rinses may cause color change in different ceramic materials. Polishing affected the color change and resulted in a decrease in ΔE values. Mouth rinses containing CHX should be recommended with caution for daily use.

Power brushing and chemical denture cleansers induced color changes of pre-polymerized CAD/CAM denture acrylic resins

Denture wearers are advised to follow the protocol of using both mechanical and chemical hygiene methods. In this study, the in-vitro color stability of heat-cured, light-cured and newly developed pre-polymerized CAD/CAM acrylic resin base materials were evaluated after exposure to mechanical brushing and chemical denture cleansers. Two polymethyl methacrylate (PMMA) (heat-cured, and pre-polymerised CAD/CAM) and one urethane dimethacrylate based resin denture base material were subjected to mechanical brushing, followed by immersion in chemical denture cleansers (Corega, 5.25% Sodium hypochlorite (NaOCl), and 0.2% chlorhexidine gluconate (CHG)) and thermal-cycling to simulate one-year of normal prosthesis use. Baseline and final color measurements were determined and the difference in color was calculated using bench-top UV light visible spectrophotometer. The highest (29.69 ± 1.84) and lowest (19.03 ± 8.78) mean ΔE was observed with light-cured and CAD/CAM materials immersed in 0.2% CHG, respectively. Tukey’s post-hoc test showed that heat cured and light-cured resins immersed in either of the denture cleansers showed no significant differences (p > 0.05) in the mean ΔE values. On the contrary, CAD/CAM materials immersed in either of the denture cleansers demonstrated significant differences in the mean ΔE values (p ≤ 0.05). A statistically significant interaction between the combination of materials and denture cleansers (F = 4.890; p = 0.001) was observed. The color stability of the pre-polymerized CAD/CAM acrylic discs is comparatively better than the conventional acrylic resin materials. The changes in the color values of all the tested materials were above the clinically acceptable range, regardless of the type of denture cleanser used.

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.

Effect of home and over the contour bleaching on stainability of CAD/CAM esthetic restorative materials

To determine the effect of home and over the counter bleaching on the stainability of CAD/CAM restorative materials, and to correlate the surface roughness with discoloration. Specimens were fabricated from feldspathic ceramic, an hybrid ceramic, a resin nano-ceramic, and lithium disilicate-reinforced glass ceramic. After baseline surface roughness (Ra1) and color measurement, each material was randomly divided into three groups according to bleaching regimen as Opalescence PF and; Opalescence Go; control. Then, the second color and surface roughness (Ra2) measurements were made. Thereafter, all specimens were immersed in a coffee solution for 12 days and the third color measurement was made. Color and whiteness change (CIELAB- ΔEab , CIEDE2000-ΔE00 , whiteness index-ΔWID ) were calculated after bleaching (ΔE1;ΔE00 1;ΔWID 1) and immersion in the coffee solution (ΔE2;ΔE00 2;ΔWID 2). According to both CIELAB, CIEDE 2000 and WID formulas, the highest mean ΔE1, ΔE2, ΔWID 1, ΔWID 2 values were observed for LAVA Ultimate groups while the lowest values were measured for e.max CAD groups. The findings also showed that there was a positively significant relationship between Ra2, and ΔE2 and ΔWID 2. Type of restorative materials and bleaching agents had an impact on color change after bleaching and immersion in coffee. Home and over-the-counter bleaching agents may cause an increase in susceptibility of restorative materials to staining.

Discoloration of Resin Composites Induced by Coffee and Tomato Sauce and Subjected to Surface Polishing: An In Vitro Study

BackgroundThe purpose of this study is to evaluate and compare color stability of 3 resin based restorative materials when immersed into staining media at 0, 3, 30, 45, 60, and 75 days, and to assess the efficacy of surface polishing in reducing possible discoloration.Material/MethodsNinety composite discs were prepared in a custom-made mold (5 mm diameter and 2 mm thick) from 3 different light cured composites (Filtek™ Z250, Harmonize™, and G-aenial). Color differences of all specimens were measured by a spectrophotometer according to the CIE L*a*b* system. After baseline color measurements, 30 discs from each composite group were randomly divided into 3 subgroups of 10 specimens each. Subgroups (n=10) were immersed for 75 days into different staining solutions: coffee, tomato sauce, and distilled water (control). Solutions were changed every week and color measurements were repeated every 15 days. At day 75, color measurements of the specimens were performed before and after surface polishing with aluminum oxide discs. The experimental data were statistically evaluated using repeated measures one-way ANOVA test followed by Tukey’s multiple pairwise comparison with a significance level of 5%.ResultsOf the 3 composites, G-aenial reported the highest color change deviation when immersed into coffee (ΔE=8.674), and tomato sauce (ΔE=7.737) at day 75, followed by Harmonize that also exhibited a significant difference for coffee (ΔE=4.7) and tomato sauce (ΔE=3.8) when compared to distilled water. While Filtek™ Z250 did not show any significant difference between the 3 storage solutions (P>0.05).Only G-aenial had significant color change (P<0.05) after polishing with aluminum oxide discs for all tested samples, whereas Filtek™ Z250 and Harmonize presented no significant difference after surface polishing (P>0.05).ConclusionsUnder the tested experimental conditions, Filtek™ Z250, among the 3 resin-based composites, exhibited the highest color stability when subjected to coffee and tomato sauce as well. Whereas, G-aenial presented the highest color deviation when immersed in both staining media.Surface polishing effectively reduced coffee and tomato sauce discolorations for G-aenial’s specimens and had no significant effect regarding Filtek™ Z250 and Harmonize.

An in vitro evaluation of the effect of polishing on the stainability of different CAD/CAM ceramic materials

PurposeTo determine the effect of coffee on the stainability of CAD/CAM ceramics after different surface treatment protocols. MethodsNinety specimens (2 mm × 10 mm) of CAD/CAM ceramic materials (Vitablocs Mark II, VITA Enamic, and VITA Suprinity) were prepared. The specimens were subdivided (n = 10) into three groups: G1: Glazed (control group), G2: Subjected to finishing and polishing, and G3: Re-glazed after finishing and polishing. The surface treatment was performed using a diamond polishing system for porcelain (Diapol) followed by applying a diamond polishing paste (Diapolisher). The specimens were immersed in distilled water for 24 h, and the baseline color measurement after finishing and polishing was recorded. Each group was then immersed in a staining solution (coffee) for one week, and the second color measurement was recorded. ResultsThe color of the CAD/CAM ceramic materials in the finishing and polishing groups changed significantly after staining (P < 0.05). Statistically significant differences were noticed after staining in the polished groups of Vita Enamic and Vita Suprinity compared with the glazed group (control). However, the color change between the re-glazed and control groups was insignificant for all the materials (P > 0.05). Although the color change values of the three CAD/CAM materials increased, these changes were within the clinically acceptable value (ΔE < 3.3). ConclusionStaining of the tested CAD/CAM ceramic materials increased the color change values within the clinically acceptable range in all the groups, with the highest values found after finishing and polishing. Re-glazing is recommended after surface adjustment for all the tested materials to increase their resistance to staining.