Difference In Color Change Research Articles

Effect of Listerine and Chlorhexidine mouthwashes with antidiscoloration system on the colour change of CAD/CAM conventional and novel lithium disilicate ceramics

Background It has been reported that using mouthwashes can discolour the surface of teeth. Their effect on the stainability of newly introduced lithium disilicate ceramics is, however, unknown. Objective: The purpose of this in vitro study was to investigate how mouth washes affected the color change of new and conventional lithium disilicate (LS2) ceramics that were finished using various techniques. Materials and Methods A total of 56 ceramic slices were produced from conventional LS2 (E Max CAD, Ivoclar) and a novel virgilite based LS2 (Cerec Tessera, Dentsply Sirona). According to the finishing method, the specimens were divided into glazed and polished subgroups. Each subgroup was further subdivided into two based on immersion in chlorhexidine (CHXD) or Listerine (LIST) mouth washes. A handheld spectrophotometer was used to measure the color attributes, and color differences (ΔE00) were then counted using specific equation. Data were analyzed using ANOVA and Tukey’s post-hoc tests. Results Significant differences in color change (ΔE00) values were observed between conventional and novel LS2 ceramics, as well as between different finishing methods and mouth-rinse solutions. Chlorhexidine induced higher color differences than Listerine, with average ΔE00 values of 0.959 and 0.885, respectively (p < 0.001). The polished specimens generally exhibited higher ΔE00 values than the glazed specimens, with average values of 1.071 and 0.792 for conventional LS2, and 0.836 and 0.786 for novel LS2 (p < 0.001). However, most color changes did not exceed the perceptibility and acceptability thresholds. Conclusion Using CHXD and LIST mouth washes affected the color change of polished or glazed conventional and novel lithium disilicate ceramics. In general, the stainability of polished specimens was higher than that of glazed ones. There was more discoloration on specimens immersed in CHXD than those immersed in LIST. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1178-1184

Color Stability Assessment of Single- and Multi-Shade Composites Following Immersion in Staining Food Substances.

Composite resins are the material of choice for direct restorations, and their success depends mainly on their color stability, since discoloration causes color mismatch, and consequent patient dissatisfaction. A single- and a multi-shade resin were compared in order to evaluate their pigmentation after immersion in staining substances and to investigate the effect of the polymerization time on their color stability. Two-hundred-and-forty composite specimens were created, half made of a single-shade (Group ONE, n = 120) and half of a multi-shade composite (Group OXP, n = 120). Each group was further divided into ONE30 (n = 60) and OXP30 (n = 60), polymerized for 30″, and ONE80 (n = 60) and OXP80 (n = 60), polymerized for 80″. Randomly, the specimens were immersed in turmeric solution, soy sauce, energy drink, or artificial saliva. By means of a spectrophotometer, ΔE00 and WId were calculated at 24 h (T0), at 7 (T1), and 30 (T2) days. Single-shade composites showed statistically significant differences in color change from the turmeric solution, energy drink, and soy sauce than the multi-shade composites (p < 0.005), showing a higher discoloration potential. The polymerization time did not have significative effects on color stability. Single-shade composites showed more color change than multi-shade systems after immersion in staining substances, and the curing time did not influence color variations.

Extending Cucumber Shelf Life: A Comparative Study of Low-Cost Drip Cooling Systems Using Different Fabric Coverings

Aims: Postharvest losses of cucumbers pose significant challenges for small-scale farmers in developing regions due to limited access to modern cold storage. This study investigated the effectiveness of low-cost indigenous drip coolers with different fabric coverings as an alternative preservation method. Study Design: Completely Randomized Design (CRD) with five treatments and three replications. Place and Duration of Study: Department of Crop Science, Surigao del Norte State University – Mainit Campus, Mainit, Surigao del Norte, Philippines on March 1-20, 2024. Methodology: Cucumber fruits were stored in indigenous drip coolers constructed with various recycled fabric coverings. Treatment combinations were: T1 - Control ambient temperature, T2 - Alpha Gina fabric, T3 - Silk satin bedsheets, T4 – Cotton comforter, and T5 - Cotton Blanket. The study evaluated color change, firmness, shriveling index, visual quality rating, weight loss, and damage rate over 20 days storage period. Results: Significant differences in cucumber fruit quality emerged at different time points across various parameters. Differences in color change and firmness were observed on day 15 (p = 0.023), while shriveling and visual quality showed differences by day 20 of storage (p = 0.042 and p = 0.042, respectively). However, in terms of weight loss, the Alpha gina fabric significantly had the highest loss among fabric covers used (p = 0.038). Consistently, the control ambient group exhibited the poorest quality, while treatments like the cotton comforter and silk satin bedsheet were most effective in preserving cucumber quality. Conclusion: This study demonstrates the effectiveness of indigenous drip coolers in preserving cucumber quality, with silk satin bedsheets and cotton comforter coverings consistently outperforming other materials and ambient conditions. These coolers were effective in slowing color change, maintaining firmness, reducing shriveling, and preserving overall visual quality. The study highlights the importance of fabric selection in drip cooler design, with cotton comforter and silk satin bedsheet coverings likely offering better air circulation, moisture retention, and insulation.

Effect of Common Staining Beverages on Color Stability of Polymer-infiltrated Ceramics and Extra Translucent Zirconia: An In Vitro Study.

The current study aims to assess the color change of polymer-infiltrated ceramic Vita Enamic (VE) and extra translucent multilayer zirconia (XTML) after being immersed in different types of beverages, which are coffee, tea, and cola in comparison to distilled water as control. A total of 80 rectangular-shaped specimens were prepared with fixed dimensions (14 × 12 × 0.5 mm) and then were divided into two groups (n = 40) according to ceramic material (VE, XTML). Specimens were sliced as each slice measures about 0.5 mm thick. Each group specimens were divided into four subgroups (n = 10) based on the immersion solutions in which specimens were stored (water, coffee, tea, and cola) for 28 days. The color parameters (L-a-b) of the specimens were recorded before immersion and at the end of the 7th (T1), 14th (T2), 21st (T3) and 28th (T4) days after immersion. Color measurements were statistically analyzed with a significance threshold of p < 0.05. There was a significant difference in color change between VE and XTML in all periods of tea and coffee immersion subgroups and in T3 and T4 in cola immersion subgroups (p < 0.001). Vita Enamic showed the highest differences in ΔE through all storage periods after 28 days of tea immersion (ΔE of VE= 8.06 ± 1.04). Extra translucent multilayer zirconia showed the highest differences in ΔE through all storage periods after 28 days of tea immersion (ΔE of XTML = 3.0 ± 0.33). Commonly consumed staining beverages influenced the color stability of the polymer-infiltrated ceramics more than extra translucent zirconia ceramics. This study may provide guidance for clinicians to select the appropriate ceramic restorative material with high color stability and low tendency for color change by common staining beverages to achieve long-lasting esthetic results for the patients. How to cite this article: Abdelhafez MHA, Abu-Eittah MRH. Effect of Common Staining Beverages on Color Stability of Polymer-infiltrated Ceramics and Extra Translucent Zirconia: An In Vitro Study. J Contemp Dent Pract 2024;25(5):411-416.

The effect of whitening toothpastes on the color stability and surface roughness of stained resin composite

BackgroundThis study aimed to investigate the effect of whitening toothpastes on the color stability and surface roughness of resin composites stained with coffee and cigarette smoke.MethodsSeventy-two disk-shaped specimens (6 × 2 mm) of suprananohybrid resin composite were randomly divided into two groups and exposed to coffee and cigarette smoke (n = 36). After staining, the samples randomly divided into four groups according to whitening toothpastes and were brushed for 4 min: Opalescence Whitening (OW); Colgate Optic White (COW); Curaprox Black is White (CPX) and, distilled water (control) (n = 9). Color was measured with spectrophotometer at the initial, after staining, and after brushing, and surface roughness was measured with profilometer at the initial and after brushing. A surface morphology analysis was examined using scanning electron microscopy and atomic force microscopy. The obtained data were statistically analyzed. (p < 0.05).ResultsCigarette smoke caused a significantly higher color change than coffee in the resin composite (p < 0.05). Brushing with hydrogen peroxide and silica-containing whitening toothpaste showed significant differences in color change (p < 0.05). The lowest whitening effect was found in activated charcoal-containing toothpaste. While all toothpastes increased the degree of surface roughness of resin composites, the highest roughness was caused by whitening toothpastes containing activated charcoal. (p < 0.05).ConclusionsThe color stability and surface properties of resin composites can be affected by brushing them with whitening toothpaste. The utilization of whitening toothpaste containing hydrogen peroxide can be considered a safe method for increasing the whiteness of discolored resin composites.

Effect of conventional cigarette smoking and recent heated tobacco products on CAD/CAM restorative materials

ObjectiveTo determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials.Materials and methodsOne hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass–ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer’s instructions.Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α < 0.05.The surface topography was evaluated by scanning electron microscopy (SEM) and analyzed using energy-dispersive X-ray (EDX) spectroscopy to determine changes in the surface chemical composition.ResultsBoth types of smoking caused significant increases in the surface roughness of all the samples. There was a significant difference in color change between CS and HTP for all materials with different surface finish (P < 0.01) and zirconia had the greatest effect on color change (P < 0.001). In contrast, polyetheretherketone (PEEK) “BioHPP” had the least effect (P < 0.001).ConclusionExposure to different types of smoking induce changes in the surface topography and color of different esthetic restorative materials. Compared with HTP, conventional cigarette smoke has a greater effect on the surface roughness and color stability of esthetic restorative materials. The glazed surfaces showed less change in surface topography than did the polished surfaces. Zirconia showed better color stability when compared to polyetheretherketone (PEEK).

Color stability of CAD-CAM hybrid ceramic materials following immersion in artificial saliva and wine.

To examine the color stability of 3D-printed and milled, interim, and definitive, restorative materials after immersion in artificial saliva and wine for 1, 3, and 6 months. The study used a 2 × 5 factorial design with 10 subgroups, including 2 immersion liquids (artificial saliva and wine) and 5 manufacturing technology and restorative material combinations (n = 10). Color measurements were taken using a contact-type digital spectrophotometer (CM-2600d Spectrophotometer; Konica Minolta Healthcare Americas Inc) before immersion and at 1 month (T1), 3 months (T3), and 6 months (T6) after immersion. The CIE2000 system was used to calculate quantitative measurements of color differences in ΔE00, and comparisons were made to the acceptability threshold (AT) and perceptibility threshold (PT). Repeated measures of ANOVA (α = 0.05) were used to compare differences in color changes between manufacturing technology/restorative material-immersion liquid combinations at T1, T3, and T6. To compare the effect of immersion liquid and time on the manufacturing technology/restorative material groups, the ΔE00 values were compared to the PT of 0.8 and the AT of 1.8. Wine caused significant color changes in ΔE00 values beyond the PT and AT values in all groups at all time intervals, except for the AT value of milled definitive crowns (hybrid nano-ceramic material). Wine immersion caused significant ΔE00 for all manufacturing technology/restorative material groups at all time intervals (1 month, 3 months, and 6 months) when compared to artificial saliva immersion (all p < 0.001). Upon exposure to artificial saliva, 80%-100% of samples from all groups remained within the acceptable and perceptible color change thresholds. The wine had significant chromogenic effects on all tested restorative materials, however, the milled definitive crowns (hybrid nano-ceramic material) showed the greatest color stability. For patients with heavy wine consumption, 3D-printed definitive crowns (hybrid ceramic-filled material) may show discoloration exceeding acceptable and perceptible color change limits.

Resin infiltration for white spot lesions: An in vitro experimental trial.

To evaluate the aesthetic outcome by varying the duration allowed for infiltrant penetration when treating white spot lesions with resin infiltration. An in vitro, experimental randomised study. Artificially created white spot lesions (WSLs) were induced on 100 extracted anterior teeth (T1). Teeth were divided into enamel and dentine groups depending on the extent of the lesion and then randomly assigned into different treatment protocol groups: penetration times of 3, 6 and 9 min. Resin infiltration treatment was applied according to the treatment protocol assigned (T2). Samples were thermocycled for 10,000 cycles (1 clinical year) (T3). The samples from the 3-min enamel and dentine groups were then randomly assigned into either a repeat treatment or no additional treatment group (T4). Samples were then thermocycled for an additional 10,000 cycles (T5). Spectrophotometric analysis was measured colour change (ΔE) for all groups. Mean ΔE values equal to or greater than the critical value (3.7) indicate a detectable clinical difference in colour of the treated WSL when compared to before WSL formation. Mean ΔE values, for the enamel groups, were slightly above or significantly below the critical value, and for the dentine groups, were significantly above the critical value. Mean ΔE values within the enamel and dentine groups both demonstrated a downward trend with increasing time allowed for resin infiltrant penetration (P < 0.05). No significant mean ΔE difference (P = 0.53) was found between groups that received a single or repeat treatment. After the first thermocycling event, no significant difference in colour change was observed in all groups except for the deep dentine lesion treated for 3 min. There was a significant difference in colour change for all groups except the enamel group that received a single treatment following thermocycling after a single or repeat treatment. Increasing the resin infiltrant penetration time to at least 9 min is advised as the most optimised treatment protocol. Resin infiltration treatment should be done only once to treat a particular white spot lesion as subsequent treatment for the same lesion results in marginal colour improvement. The colour improvement of WSLs resulting from the resin infiltration treatment can be expected to last for at least 1 year. Resin infiltration treatment of shallow lesions with a single and optimised infiltration technique can be expected to last an additional year.

Color Stability of Re-Injection Acetal Resin with Different Percentages or Several Times

Studies in a variety of scientific disciplines have experimented with various techniques for recycling and reusing the materials they utilize on a regular basis, in this study suggest to re cycling waste of acetal resin.Purpose: The purpose of this study was to assess and compare the color change of re-injection acetal resin with different percentages or several times.Material and Methods: Specimens were prepared with dimensions (20±1 mm in diameter x 0.5 mm in thickness) for color stability test and injection according to the manufacture’s instruction for acetal resin as denture base materials and aesthetic clasp. The first group represent control group with (100% New) and other five groups as experimental groups (group II, group III, and group III) with different percentages between new acetal materials and old acetal materials, while two last groups with several times (group IV and group V) only used old acetal materials. Preparation the ratio between the new material with the old material according to pilot study and the best ratio in this study is 25% new acetal material and 75% old acetal material (group II). The old material is preparation by acetal sprue is collected and cutting by cutter and re-injection with new acetal resin.Results: Statistically non-significant difference in color change in re-injection acetal resin, when comparing the control group with mean (1.046±0.094) and re-injection groups with means respectively (1.040 ±0.076,0.942±0.115,0.993±0.137, 0.978±0.060, and 0.970±0.098).Conclusion: Color change was statistically non-significant differences between all studied groups.

Effect of UV radiation on postharvest conservation of blueberries

The objective of this work is to determine the variation in the nutritional and quality characteristics of blueberries subjected to UV radiation. Blueberries of the variety (JEWEL) provided by Tierra de blueberries, Oran, Monteros, Tucuman were used. The parameters analyzed were variations of the color and content of polyphenols by HPLC and UV-vis. Polyphenols determined by HPLC were: delfinidin-3-galactoside, delfinidine-3-glucoside, cyanidin-3-galactoside, delfinidin-3-arabinoside, cyanidin-3-glucoside, petunidin-3-galactoside, cyanidin-3-arabinoside, petunidin-3-glucoside, peonidin-3-galactoside, petunidin-3-arabinoside, malvidin-3-galactoside and malvidin-3-glucoside. From the results obtained, it is concluded that the polyphenol content varied in the irradiated fruits and in the untreated fruits as a function of time, with the values being closest to the initial time value (control) in the case of irradiated fruits. There were no appreciable differences in color change due to irradiation. At time 0, the color difference in the whole fruit between the treated sample (IFC0) and the standard (NFC0) gave ΔE* values equal to 2.06. After 3 days, the color difference was 3.08 for the natural sample and 6.06 for the treated sample. For this reason, it is considered that irradiation of blueberries is a very appropriate method for conservation, maintaining the nutritional and quality characteristics of blueberries.

Color Change based on Mixing Ratio of Acidic Hair Dye by Hair Brightness

Purpose: This study seeks to examine the difference in color change depending on the mixing ratio of acidic hair dye and hair brightness and provide baseline data on the color change of hair dye using acidic hair dye.Methods: Gray, ash blue, pink, and orange colors were used alone, mixed with gloss in transparent color in the ratio of 1:1, 1:10, and 1:20, and were applied to unbleached hair, once, twice, and three times bleached hair, respectively, and color images were taken. The L&lt;sup&gt;*&lt;/sup&gt;a&lt;sup&gt;*&lt;/sup&gt;b&lt;sup&gt;*&lt;/sup&gt; values were measured using a spectrophotometer, and their average value was obtained.Results: It was found that when acidic hair dye was used alone, hair was less bright and more saturated. Brightness increased more when acidic hair dye was mixed with transparent shimmering gloss. Also, when dyeing with pink and orange colors, it was possible to express the desired color on once-bleached hair even with a high value of yellow color. Bright grey and ash-blue color could be expressed when the gray color was bleached three times. For the pink color, high saturation could be expressed on once-bleached hair. For orange color, it was found that various orange colors could be expressed.Conclusion: This study is meaningful in that it enhances customers’ satisfaction with hair coloring and increases the efficiency of hair dyeing service by minimizing the error between the objective color desired by the designer and the customer, and the resulting color.

The effect of imposing apple (Malussylvestris Mill) juice on discoloration of nanofiller and nanohybrid composites

Composite resin can undergo discolouration if exposed to dyes. The use of apples can whiten teeth because they contain ma-lic acid. True experiment research with pretest-posttest with control group design using 24 samples divided into 6 treatments, namely sample groups 1 and 2 (nanofiller and nanohybrid composite groups that have been discoloured soaked in apple fruit juice (Malus sylvestris Mill) 80% concentration, groups 3 and 4 (negative control group, discoloured nanofiller and nanohy-brid composites soaked in distilled water) and groups 5 and 6 (positive control group, discoloured nanofiller and nanohybrid composites soaked in 10% carbamide peroxide). The colour change was determined with a shade guide (Vitapan Classical). The results were normally distributed and homogeneous. One-way Anova test showed there was a significant difference in each group. In the independent t-test, there was a significant difference in colour change between nanofiller and nanohybrid composite resins that experienced discoloration in 80% apple juice immersion. It was concluded that nanofiller composite resin had lower discolouration compared to nanohybrid.

Comparative Effects of Three Bleaching Techniques on Tooth Discoloration Caused by Tea.

Objectives: This study aimed to investigate the impact of three different bleaching protocols on tooth discoloration caused by tea. Materials and Methods: Forty extracted sound premolars were cleaned, disinfected, and their initial color parameters were measured (T1). The teeth were then immersed in boiled tea solution for 24 hours, and their color was measured again (T2). The samples were divided into four groups of 10 teeth each. Group A was treated with an in-office bleaching gel followed by 30 seconds of light curing. Groups B, C, and D were respectively treated with 0.24M oxalic acid followed by bleaching gel, 5.25% sodium hypochlorite followed by bleaching gel, and a combination of 0.24M oxalic acid, 5.25% sodium hypochlorite, and bleaching gel. The color was measured once more after the interventions (T3). Data were analyzed using two-way repeated measures ANOVA, paired sample t-test, and Tukey's test. Results: The mean color change (∆E2) between T2 and T3 was significantly higher in group D compared to group A (P<0.05). However, there was no significant difference in color change between groups A, B, and C. Additionally, there was no significant difference in color change between groups B, C, and D. The groups also showed significant differences in ∆L (P=0.007), with the only significant difference found between groups B and C (P=0.001). Conclusion: The combined use of sodium hypochlorite and oxalic acid followed by in-office bleaching gel is more effective than bleaching alone in correcting tooth discoloration caused by tea. This protocol can further reduce yellow coloration.

Does the composite attachment of clear aligners compromise the effectiveness of dental bleaching? An in vitro study

This study aimed to evaluate the effectiveness of dental bleaching with hydrogen peroxide 35% on the surface below the attachments. Twenty-four blocks of bovine incisors were equally divided into 2 groups. The control group comprises the enamel surface free of attachments, whereas the attachment group comprises the enamel surface with attachment. Initial staining of samples was performed with black tea for 7 days; then, an attachment was made in the attachment group with Z250 resin and new staining for another 7 days in all samples. After staining, in-office bleaching was performed in both groups, and the attachments from the attachment group were removed. Color reading was performed with a spectrophotometer at all stages: initial (baseline), after 7 days of staining, after 14 days of staining, after immediate bleaching, and after 24 hours of bleaching. The color difference was calculated, and data analysis was performed using the t test for intergroup analysis. The results showed effective bleaching in both groups; however, there was a statistically significant difference in color change between them 24 hours after bleaching. It was concluded that the presence of attachment did not impair the action of the bleaching agent on the tooth surface.

THE EFFECT OF MAULI BANANA (Musa acuminata) STEMS AND BASIL LEAVES (Ocimum basilicum) EXTRACTS ON GIC DISCOLORATION

Background: The water settable GIC material is easily influenced by fluids and is hydrophilic which causes discoloration of the restoration. Chlorhexidine is the gold standard mouthwash and if used for a long period of time it can cause discoloration of the restoration because it contains chemicals, so an alternative mouthwash made from natural ingredients is needed. A mixture of mauli banana stem and basil leaves extract has a more optimal antibacterial ability. Objective: In general, this study aimed to analyze the effect of a mixture of Mauli banana stem (Musa acuminata) and basil leaves (Ocimum basilicum) extracts on discoloration of the water settable GIC. Methods: This research is a true experimental research with pre test and post test designs with control group design. This study was divided into three treatments, namely water settable GIC soaked in a mixture of extracts of banana stems and basil leaves at concentrations of 75%, 100%, and 0.2% chlorhexidine gluconate (positive control). Color measurement was carried out using a series of digital analysis tools consisting of a Samsung A1 macro camera, Peyond series PD-480 SL and the MATLAB application. Results: The results of the Kruskal-Wallis statistical test showed p value = 0.282 (&gt; 0.05), meaning that there was no significant difference in color change between the three treatments. Conclusion: There is an effect of a mixture banana mauli stems (Musa acuminata) and basil leaves (Ocimum basilicum) extracts at concentrations of 75%, 100%, and 0.2% chlorhexidine gluconate on the discoloration of the water settable GIC. Keywords: Basil leaves (Ocimum basilicum), CIELAB system, discoloration, mauli banana stem (Musa acuminata), water settable GIC

Evaluation of the Effectiveness of Tooth Whitening of Using Reservoir in Bleaching Trays as Compared to Using Bleaching Tray without the Reservoir: An Observational Clinical Trial

Background: Bleaching procedures have gained importance due to the increase in aesthetic demand. At-home bleaching procedures have become popular due to their ease of application at their own time. At-home bleaching procedures can be modified to increase effectiveness. Aim: The present study aims to compare the effectiveness of tooth whitening by using bleaching trays with reservoirs and ones without reservoirs. Materials and Methods: The present study is an observational clinical trial done on 24 patients in Palestine. All the caries-free participants with Canine shades darker than A2 were included in the present study. The sample was divided into two groups. One group received bleaching trays with a reservoir, another group received bleaching trays without a reservoir. 10% carbamide peroxide was used as a bleaching agent in both groups for 21 days with 3-hour wear of trays. The primary outcome measured in the study was color change using the spectrophotometer VITA Easyshade. The secondary outcomes measured in the study were post-bleaching gingival irritation and tooth sensitivity. Statistical analysis was done using SPSS software. T-test was done to compare the primary outcomes between the two groups and the Chi-square test was done to compare the secondary outcomes. Results: T-test showed that there is no significant difference between the color change in the two groups. The chi-square test showed that there is no significant difference in the occurrence of gingival irritation and tooth sensitivity between the two groups (P&gt;0.05). Conclusion: There is no significant difference in color change between the bleaching tray with the reservoir and without the reservoir. There is no significant difference in the increase in gingival irritation or tooth sensitivity between the two groups. Further studies and meta-analyses need to be conducted to obtain more evidence-based data on the outcomes.

Repeated Etching Cycles of Resin Infiltration up to Nine Cycles on Demineralized Enamel: Surface Roughness and Esthetic Outcomes-In Vitro Study.

Resin infiltration (RI) is used to mask enamel opacities. There are three recommended etching cycles. However, anecdotal evidence suggests that favorable esthetics outcomes can be obtained by increasing the etching cycles. This study aimed to evaluate the effects of repeated etching cycles during RI application on esthetic changes and surface roughness of demineralized enamel at multiple treatment stages. Artificial demineralization was prepared on the buccal surface of ninety sound extracted premolars. The teeth were divided into nine groups (n = 10); with each consecutive group having one additional etching cycle up to nine etching cycles. Resin infiltrant was performed twice, first for 3 min (Resin 1) and again for 1 min (Resin 2). Surface roughness and esthetic changes were assessed using a profilometer (Ambios XP-200) and Minolta spectrophotometer, respectively, at baseline (sound enamel), etching, resin 1, resin 2, 7 days, and 28 days post resin applications. Data were analyzed with two-way ANOVA (p < 0.05). There was a significant interaction between the different stages and various groups of etching cycles on surface roughness, F(48, 126) = 3.48, p < 0.001. There was a significant interaction between the different stages and various groups of etching cycles on color changes, F(4, 126) = 1.177, p = 0.045. The surface roughness of demineralized enamel infiltrated with RI was less than that of sound enamel (baseline). There is a significant difference in color changes between resin 1 and resin 2 (p < 0.05). After five etching cycles, RI improved the esthetic of the color of teeth similar to the baseline. Surface roughness and color changes remained constant for 28 days. RI can be considered an effective and predictable treatment option for the restoration of early enamel lesions owing to its better surface characteristics and reliable masking effects. The color stability and surface roughness stay unaltered for up to 28 days.

The effects of different repolishing procedures on the color change of bulk-fill resin composites.

The purpose of the study was to investigate the impact of repolishing procedures on the color change of bulk-fill resin composites after being exposed to coffee. Four bulk-fill resin composites (Filtek One bulk-fill, Tetric EvoCeram bulk-fill, Admira Fusion x-tra bulk-fill, Grandio SO x-tra bulk-fill) were tested. Sixty samples were prepared with each resin composite and were randomly divided into two groups: first one received the one-step polishing system (Optragloss) and the other group received the two-step polishing system (Nova Twist) (n=30). After being kept in coffee for 12 days, the samples were divided into three subgroups according to repolishing: one-step repolishing group, two-step repolishing group, and non-repolishing group (n=10 for each). Color measurements of the resin composite samples were determined with a spectrophotometer. The difference in color change was calculated using the CIEDE 2000 color formula. The data were analyzed using three-way ANOVA and Tukey test. Among composite materials, Filtek One bulk-fill (1.84 ± 0.98) less color change was observed compared to others (p<0.001). In terms of polishing systems, Optragloss (2.96 ± 1.51) showed significantly greater color change than Nova Twist (2.21 ± 1.07) (p<0.001). The non-repolishing group (3.78 ± 1.25) presented significantly greater color change than the Nova Twist sytem (1.49 ± 0.61) and Optragloss system (2.50 ± 1.01) (p<0.001). The repolishing process reduced discoloration. A two-step repolishing system results in less color change compared to a one-step repolishing application. In polishing systems containing diamond particles, increasing the number of steps can contribute to color stability.

Perceptual and quantitative analysis of discoloration of orthodontic elastomeric chains by food

BackgroundThe objectives of this study were to use a digital camera to measure the discoloration of orthodontic elastomeric chains in various immersion solutions over different time periods and to determine the valid acceptability tolerances for color changes in orthodontic elastomeric chains by surveying digital photographs.MethodsOrthodontic elastomeric chains were applied to the maxillary anterior teeth of nine typodont models. The models were divided into three groups and immersed in the curry, coffee, and wine solutions. The digital images of the elastomeric modules were captured and processed using commercial software after 30 min of immersion, thrice a day, for 28 days. The differences in color changes (Delta {text{E}}), depending on the type of immersion solution and period, were analyzed using a repeated-measures analysis of variance (ANOVA) test. A web-based survey questionnaire was randomly distributed to 50 respondents for a visual analysis of the elastomeric chain discoloration. The relationship between the surveying score and Delta {text{E}} value was analyzed using Spearman’s correlation coefficient. The perceptibility and acceptability of elastomeric chain discoloration (Delta {text{E}}) based on the type of immersion solutions and periods were analyzed using a regression model.ResultsSignificant differences were observed in the discoloration of the elastomeric power chain depending on the immersion solution and period. The amount of discoloration was highest in curry, followed by coffee and wine (P < 0.05). The mean discoloration (Delta {text{E}}) continued to increase over the entire immersion period. There was a significant correlation between visual scoring and discoloration (Delta {text{E}}) over the entire period, especially in the early stages compared to the later stages (r = 0.918, P < 0.05). In 50% of the respondents, the predicted clinically unacceptable discoloration was between 4.46 and 9.98 and in 90% of the respondents, it was between 16.52 and 19.85.ConclusionsThe amount of discoloration was the highest for curry, followed by coffee and wine, and continued to gradually increase during the observation period. Significant differences were found between the color measurements obtained and the visual assessment by observers. The observers varied in their tolerance for perceptibility and acceptability for elastomeric chain discoloration based on the type of dietary media.

Colour Stability Of Bulk Fill Composites: A Systematic Review

Background: The introduction of Bulk-Fill (BF) composite materials, among other new preparations, was one of the most recent innovations in operative dentistry. All bulk composites' colour stability is a source of concern. There has been a lot of research on the effects of different drinking solutions on the colour consistency of conventional resin-based composites, but little has been written about the colour changes of BF composite resins, which have been developed for the placement of somewhat thicker layers.&#x0D; Aim: Thus, the objective of this systematic review was to assess the colour consistency of various bulk-filled composites.&#x0D; Methods and Materials: A massive exploration of preexisting literature was done in order to locate all relevant research that addressed the sustainability of colour of BF composites under the effect of various. According to PRISMA standards, the current systematic evaluation was carried out. A thorough search for non-controversial existing literature on the websites like PubMed portal, MEDLINE portal, and Scopus portal was done in December 2022. There were no comparable articles in Cochrane online library. To make sure that all pertinent studies were found, search keywords were applied. Furthermore, all appropriate scientific papers from Jan 2010 to December 2022 on the effect of various beverages, polishing techniques, storage media, and oral fluids, bleaching protocols on the colour longevity of bulk-filled composite samples were included.&#x0D; Results: 18 studies were evaluated in this systematic review. 9 studies focused on the effect of different drinks and beverages like tea, coffee, wine, and acidic beverages over the changes in the colour of bulk-filled composites. There were 4 studies that evaluated the impact of different polishing mechanisms. There were 2 researches that described the influence of different bleaching techniques over the change in colour of bulk-filled composites. One study discussed the effect of reinforcement of glass fibers and polythene fibers in bulk-filled composites, the presence of different dentin substitutes and water solubility and water sorption impact over the change in colour. The number of specimens evaluated ranged from n=20 to n=800 across all the included studies. There was the use of two to ten composite materials across all the included studies.&#x0D; Conclusion: When there was an analysis of the effect of different beverages and drinks over the changes in colour then there were mixed results. Some studies found that colour changes in bulk-filled composites are lesser than in customary composites. While some studies revealed that alteration in colour is greater in bulk-filled composites when compared to customary composites. Some studies found no significant difference in colour change in conventional composite and bulk-filled composite. The polishing operations can have a serious influence on the staining impedance of bulk-fill composite resins.