Determination of the whitening effect of toothpastes on human teeth / Determinación del efecto blanqueador de los dentífricos en dientes humanos

Abstract The desire of individuals to have whiter teeth increases the interest in tooth whitening products. Our aim was to in vitro study the whitening effect of hydrogen peroxide, blue covarine and active charcoal containing whitening toothpastes on human teeth. A total of 40 extracted human incisor teeth were used in the study. To measure the whitening effect of toothpastes, the teeth were divided into four subgroups and placed in the phantom tooth jaw model. Then, daily brushing was done with an electric toothbrush. The colors of the teeth were measured initially using the spectrophotometer (single point and bleached shade mode) and at the end of 7th, 14th and 28th days. Whitening effectiveness of toothpastes were studied according to CIEDE2000 formula (ΔE00) and shade guide units (SGU). One- way analysis of variance (ANOVA) and Tukey test were used in the statistical analysis of the data. (p0.05). Blue covarine containing toothpaste had statistically the lowest whitening effect (p<0.05). All toothpastes showed a whitening effect on the teeth after 7 days of use. Activated charcoal containing toothpaste showed more whitening effect after 28 days of use than hydrogen peroxide, blue covarine and traditional toothpaste.

Resumen El deseo de los individuos de tener unos dientes más blancos aumenta el interés por los productos de blanqueamiento dental. Nuestro objetivo fue estudiar el efecto blanqueador de las pastas dentales blanqueadoras que contienen peróxido de hidrógeno, covarina azul y carbón activo en dientes humanos in vitro. En el estudio se utilizaron un total de 40 dientes incisivos humanos extraídos. Para medir el efecto blanqueador de los dentífricos, los dientes se dividieron en cuatro subgrupos y se colocaron en el modelo de diente fantasma en mandíbula. A continuación, se realizó un cepillado diario con un cepillo eléctrico. El color de los dientes se midió inicialmente con un espectrofotómetro (modo de punto único y tono blanqueado) y al final de los días 7, 14 y 28. Se estudió la eficacia blanqueadora de los dentífricos según la fórmula CIEDE2000 (ΔE00) y las unidades de guía de color (SGU). En el análisis estadístico de los datos se utilizó el análisis de varianza de una vía (ANOVA) y la prueba de Tukey. (p0,05). El dentífrico que contiene covarina azul tuvo estadísticamente el menor efecto blanqueador (p<0,05). Todos los dentífricos mostraron un efecto blanqueador en los dientes después de 7 días de uso. Los dentífricos con carbón activado mostraron un mayor efecto blanqueador tras 28 días de uso que el peróxido de hidrógeno, la covarina azul y el dentífrico tradicional.

Effect of finishing and polishing systems on the surface roughness and color change of composite resins.

BACKGROUND: This study is to examine the surface roughness and color changes occurring on composite resins following the application of different finishing and polishing systems. MATERIAL AND METHODS: In our study, a total of 200 samples were prepared from composites resin (6×2 mm) containing supra-nano, submicron hybrid, nanohybrid, nano-ceramic and microhybrid filler. They were polished with diamond, aluminum oxide, silicon carbide finishing and polishing systems. The initial color values of composite samples were measured with a spectrophotometer and surface roughness values with a profilometer. After that, samples were immersed of coffee solution and color measurements were repeated on the 1st and 7th day. The differences between surface roughness (Ra) and color change values (∆Eab) were evaluated using two-way analysis of variance (ANOVA) test (p<0.05). RESULTS: Finishing and polishing systems produced a statistically significant difference between the surface roughness values of nano-ceramic, submicron hybrid and microhybrid composite resin samples (p<0.05). Supra nano composite, which showed the lowest surface roughness after all finishing and polishing systems, showed the least color change after 7 days compared to other composite groups (p<0.05). The microhybrid composite with the highest surface roughness was the most color changing composite group (p<0.5). CONCLUSIONS: The spiral finishing and polishing system containing diamond particles was the system to provide the least color difference on all composite groups. However, color differences of all composite resin groups were found to exceed the perceptibility threshold (PT) and acceptability threshold (AT). Key words:Composite resin, color stability, surface roughness.

Investigation the effects of whitening toothpastes on color change of resin-based CAD/CAM blocks.

INTRODUCTION: Some colorant foods and beverages cause undesired discoloration on dental restorations. The aim of this study was to investigate the effect of whitening kinds of toothpaste with different active ingredients on the color change of resin-based CAD/CAM blocks. MATERIAL AND METHODS: In the study, resin-based CAD/CAM block samples sized 1.5 × 7 × 12 mm, were prepared. Then, to simulate the time-dependent color change, the samples were immersed in coffee (Nescafe Classic, Nestlé) for 14 days. After the color change values of the samples colored in coffee were measured by spectrophotometer, the samples were brushed with different types of whitening toothpastes for 4 minutes. Statistical analysis of the color change (ΔE00 ) was performed using the one-way analysis of variance (ANOVA). RESULTS: Color differences occurring on all resin-based CAD/CAM blocks immersed in coffee for 14 days exceeded the 50%:50% perceptibility threshold (PT) (ΔE00 :0.8). There was no statistical significant difference between the whitening toothpastes containing activated charcoal, hydrogen peroxide (HP), blue covarine pigment, and microparticles in color improvement on resin-based CAD/CAM blocks (P > .05). CONCLUSION: It has been verified that the discoloration on resin-based CAD/CAM blocks exhibiting color difference above the PT after coffee immersion can be reduced by utilizing toothpastes containing whiteners. CLINICAL SIGNIFICANCE: Color changes that occur over time in resin-based CAD/CAM blocks can be a clinical problem. These color changes in the materials can be reduced below the PT level using whitening toothpastes.

Cytotoxic Effects of Bulk-Fill Composites on L929 Fibroblast Cells / Efeitos citotóxicos dos compósitos bulk-fill em células de fibroblastos L929

Objective: Unlike traditional composite resins, bulk-fill composite resins could be polymerized as thicker layers. This study aims to contribute to the field by investigating the cytotoxic effects of various bulk-fill composite resins on L929 mouse fibroblast cells in vitro. Material and Methods: In our study, six bulk fill and one conventional composite resin were used. Composite resin samples (8×4 mm) were prepared in a sterile cabinet by using a glass mod and polymerizing with a led light device (DTE LUX E, Germany). Composite samples (n:3) of which surface area was calculated according to ISO 10993-12: 2012 standards (3 cm2/ml), were kept in media for 24 h and 72 h in 37 oC incubator, their extracts were filtered in 1:1 and 1:2 proportion and were added on L929 mouse fibroblast cells. Cell viability was examined by the MTT assay and cell death by the LDH test. Cell viability results were evaluated using one-way analysis of variance (ANOVA) test (p<0.05). Results: When the 1:1 extracts from 4 mm thick bulk-fill composite samples were applied on L929 mouse fibroblast cells, cell viability rates showed significant differences compared to the control group at the end of 24 h and 72 h (except for Estelite Bulk Fill Flow). Although the extracts of the tested composite samples at 1:1 and 1:2 ratio at the end of 72 hours caused a decrease in L929 mouse fibroblast cell viability, the cell viability rate of only PRG-containing bulk fill composite and conventional composite remained below the cell viability ratio (70%) specified in ISO standards. Bulk fill composites did not produce toxic effects (except Beautifil Bulk Restorative) according to the LDH test. Conclusions: Despite decreasing in general the cell viability, bulk-fill composite resins used in 4 mm thick layers provided cell viability rates over the acceptability level, except PRG-containing bulk fill composite (Beautifil Bulk Restorative), which was cytotoxic to L929 mouse fibroblasts. (AU)

Objetivo: Ao contrário das resinas compostas tradicionais, as resinas compostas bulk-fill podem ser polimerizadas como camadas mais espessas. Este estudo visa investigar in vitro os efeitos citotóxicos de várias resinas compostas bulk-fill em células de fibroblastos de camundongo L929.Material e Métodos: Em nosso estudo, seis resinas tipo bulk fill e uma resina composta convencional foram usadas. Amostras de resina composta (8 × 4 mm) foram preparadas em gabinete estéril usando um molde de vidro e polimerizado com um dispositivo de luz LED (DTE LUX E, Alemanha). Amostras compostas (n=3) cuja área de superfície foi calculada de acordo com os padrões ISO 10993-12:2012 (3cm2/ml), foram mantidas em meio e incubadas por 24 h e 72 h a 37 ºC, seus extratos foram filtrados na Proporção de 1:1 e 1:2 e foram acondicionados em cultura de células de fibroblastos de camundongo L929. A viabilidade celular foi examinada pelo ensaio MTT e a morte celular pelo teste LDH. Os resultados de viabilidade celular foram avaliados usando o teste de análise de variância (ANOVA) um fator (p <0,05). Resultados: Quando os extratos foram plaqueados na proporção 1:1 de amostras de compósito bulk-fill de 4 mm de espessura com as células de fibroblastos de camundongo L929, as taxas de viabilidade celular mostraram diferenças significativas em comparação com o grupo controle no final de 24 h e 72 h (exceto para Estelite Bulk Fluxo de enchimento). Embora os extratos das amostras compostas testadas na proporção de 1:1 e 1:2 ao final de 72 horas tenham causado uma diminuição na viabilidade das células de fibroblastos de camundongo L929, a taxa de viabilidade celular apenas do compósito de preenchimento total contendo PRG e o compósito convencional permaneceram abaixo a taxa de viabilidade celular (70%) especificada nas normas ISO. Os compósitos de preenchimento a granel não produziram efeitos tóxicos (exceto Beautifil Bulk Restorative) de acordo com o teste de LDH. Conclusão: Apesar de diminuir em geral a viabilidade celular, as resinas compostas bulk-fill usadas em camadas de 4 mm de espessura forneceram taxas de viabilidade celular acima do nível aceitável, exceto o compósito bulk fill contendo PRG (Beautifil Bulk Restorative), que foi citotóxico para fibroblastos de camundongos L929 (AU)

Impact of various finishing and polishing techniques and composite materials on Candida albicans biofilm formation.

Candida albicans biofilms are commonly associated with severe oral infections. In dentistry, prosthetic and restorative materials are potential structures for the adhesion of C. albicans facilitating the formation of Candida biofilm and infection. Three composite resins (Charisma Classic, Sonic Fill, Estelite ∑ Quick) and two finishing-polishing systems (Biscover LV, Dental Finishing Disc) were evaluated for Candida biofilm formation. A Candida biofilm assay showed that both the resin and the finishing/polishing procedures affect Candida biofilm formation. Specifically, Candida biofilm formation was significantly lower in Sonic Fill resin than both Charisma Classic and Estelite ∑ Quick (P = .021). The type of finishing and polishing procedure also significantly affected the Candida biofilm formation to composite material (P < .001). Candida biofilm formation was more advanced after Biscover LV procedure than Dental Finishing Disc procedure.

Evaluating of cytotoxic effects of highly esthetic dental composites / Avaliação dos efeitos citotóxicos de resinas compostas altamente estéticas

Objective: Dental composites developed by using nanotechnology in the field of dentistry are widely used in the treatment of anterior and posterior teeth. This study aimed to investigate the cytotoxic effects of dental composites of different particle size on L929 mouse fibroblast cell line by extract test method in vitro. Material and Methods: Composite samples of 8 x 2 mm diameter were prepared by polymerizing with led light device by using glass mod in a sterile cabinet. Composite samples of which surface areas were calculated according to ISO standards (3 cm2 / ml), were incubated for 24 and 72 hours, at 37 o C. cell viability was assessed by 3-[4,5-dimethylthiazole-2- yl]-2,5-diphenyltetrazolium bromide (MTT) assay and cell death was evaluated by the lactate dehydrogenase (LDH) leakage assay. Results: The 1:1 extracts of the composites at the end of 24 hours (except for nanoceramic composite) showed no toxic effect. When the cell viability results of the 1:1 extracts of the composite samples at the end of 72 hours were statistically analyzed, significant differences were found comparing to the control group (p < 0.05). Conclusion: It was observed that the type and size of the filler were effective on the toxicity of the composites, and the composites containing Bis-GMA, TEGDMA, UDMA and Bis EMA monomers in their organic matrix showed acceptable cell viability (70%) as specified by ISO. However, the composites with PEGDMA and BPA monomers in their organic matrix showed poor cell viability, which is below the acceptable level of 70%, and were found to have a toxic effect. (AU)

Objetivo: As resinas compostas desenvolvidas pela nanotecnologia no campo da odontologia são amplamente utilizadas no tratamento de dentes anteriores e posteriores. Este estudo teve como objetivo investigar os efeitos citotóxicos de resinas compostas de diferentes tamanhos de partículas na linha celular de fibroblastos de camundongos L929 pelo método de teste de extrato in vitro. Material e Métodos: Amostras compostas de 8 x 2 mm de diâmetro foram preparadas por polimerização com dispositivo de luz led usando um molde de vidro em um gabinete estéril. Amostras de resinas cujas áreas de superfície foram calculadas de acordo com os padrões ISO (3 cm2 / ml), foram incubadas por 24 e 72 horas, a 37 o C. A viabilidade celular foi avaliada pelo ensaio de brometo de 3- [4,5-dimetiltiazol-2- il] -2,5-difeniltetrazólio (MTT) e a morte celular foi avaliada pelo ensaio de infiltração de lactato desidrogenase (LDH). Resultados: Os extratos 1: 1 dos compósitos ao final de 24 horas (exceto o composto nanocerâmico) não apresentaram efeito tóxico. Quando os resultados de viabilidade celular dos extratos 1: 1 das amostras compostas ao final de 72 horas foram analisados, estatisticamente, foram encontradas diferenças significativas em relação ao grupo controle (p < 0,05). Conclusão: Observou-se que o tipo e tamanho da carga foram eficazes na toxicidade dos compósitos, e os compósitos contendo os monômeros Bis-GMA, TEGDMA, UDMA e Bis EMA em sua matriz orgânica apresentaram viabilidade celular aceitável (70%) como especificado pela ISO. No entanto, os compósitos com monômeros PEGDMA e BPA em sua matriz orgânica apresentaram baixa viabilidade celular, que está abaixo do nível aceitável de 70%, e foram encontrados como tendo um efeito tóxico. (AU)

Comparison of the Effects of Various Methods Used to Remove Adhesive from Tooth Surfaces on Surface Roughness and Temperature Changes in the Pulp Chamber.

OBJECTIVE: The purpose of the present study was to compare the effects of three methods of removing adhesive on enamel surface roughness and dental pulp temperature. METHODS: Ninety human maxillary premolars were randomly divided into three groups (n=30) according to the type of adhesive clean-up procedure: aluminum oxide-based burs, erbium-doped yttrium aluminum garnet (Er:YAG) laser, and tungsten carbide bur. The surface roughness of enamel was measured using a non-contact optical profilometer. After the first readings of surface roughness were measured (T1), orthodontic brackets were attached to the enamel surface with composite. The brackets on the teeth were debonded using bracket removal pliers. The residue of adhesive was eliminated from the enamel surface of the teeth by different procedures in each group. While removing adhesive from the tooth surface, the intrapulpal temperature rise was simultaneously measured using a thermocouple. One-way ANOVA and post-hoc Tukey HSD tests were used to analyze data with a significance level set at 0.05. RESULTS: The highest roughness average (Ra) values were observed for the Er:YAG laser group, with a significant difference with the aluminum oxide bur group and tungsten carbide bur group (p<0.001). Ra values for the aluminum oxide bur group were significantly lower than those for the other groups (p<0.001). Comparing the thermal changes in each group showed a significant decrease in the Er:YAG laser group, but a significant increase in two other groups. CONCLUSION: Within the limitations of the present study, one-step finisher and polisher bur created the smoothest enamel surface, whereas Er:YAG laser the roughest. Tungsten carbide and aluminum oxide-based burs generated more heat than Er:YAG laser.

The Efficacy of Laser Doppler Flowmetry, Electric Pulp Test and Cold Test in Diagnosing Revascularization of Extrusively Luxated Immature Maxillary Incisors.

OBJECTIVE: To evaluate the effect of extrusion on immature permanent tooth PBF values during a 6-month post-trauma period and to compare the accuracy of cold tests on pulp sensibility of traumatized teeth with that of electric pulp tests (EPT). METHODS: The study group comprised of 26 extruded immature maxillary incisors in 25 trauma patients. The respective contralateral homologous teeth (n=25) were included as a positive control group. Teeth in the study group were treated by repositioning and splinting. Pulp vitality readings for traumatized and control teeth were taken with LDF, EPT and cold test on the day of splint-removal (2-3 weeks after trauma-T1) as well as 6 weeks (T2), 3 months (T3) and 6 months (T4) post-trauma. Student t and Mann-Whitney U-tests were used to compare data among groups. Statistical significance was set at P< 0.05. RESULTS: LDF gave positive vitality readings (>4.5 PU) in all patients from T1 to T4 (with the exception of 1 patient at T1). CONCLUSIONS: LDF was able to accurately identify vitality in traumatized immature teeth even during the first few weeks following trauma, whereas conventional sensibility tests were unable to accurately recognize vitality shortly after trauma.

Dental resin curing blue light induces vasoconstriction through release of hydrogen peroxide.

Dental resin curing blue light (BL) is frequently used during treatments in dental clinics. However, little is known about the influence of BL irradiation on pulpal blood vessels. The aim of the present study was to investigate the mechanism of effect of BL irradiation on vascular tone. Rat aorta (RA) rings were irradiated with a BL source in organ baths, and the responses were recorded isometrically. Effect of BL irradiation on phenylephrine (PE) -precontraction and acetylcholine (ACh) -induced relaxation after PE -precontraction were obtained and compared in BL -irradiated and control RA rings. Effect of 20 min preincubation with catalase (enzyme that breaks down hydrogene peroxide, 1200 u/ml) on PE -precontraced and BL-irradiated rings was also evaluated. Total oxidative stress (TOS) and total antioxidant capacity (TAC) in BL-irradiated and control RA preparations were measured with special assay kits and spectrophotometry. BL slightly decreased ACh -induced endothelium -dependent relaxations in PE (1 µM) -precontracted RA rings (n = 6, p > 0.05 vs. control). BL induced marked contraction 23.88 + 3.10% of PE (maximum contraction) in isolated RA ring segments precontracted with PE (p < 0.05 vs. control). The contractile effect of BL was inhibited by 1200 u/ml catalase (n = 6, p < 0.05 vs. control). BL irradiation increased the level of TOS in RA rings (n = 6, p < 0.05 vs. control). TAC levels were similar in BL-irradiated and control preparations. These results suggest that BL induces contraction in RA, and the mechanism of this effect may to be through release of hydrogen peroxide.

Effect of intracanal medicaments used in endodontic regeneration on the push-out bond strength of a calcium-phosphate-silicate-based cement to dentin.

OBJECTIVE: To evaluate the effects of various endodontic regeneration agents on the push-out bond strength of Endosequence Root Repair Material (ERRM) to root-canal dentin. METHODS: Fifty single-rooted human teeth were selected and instrumented to obtain a standard internal diameter of 1.5 mm. Specimens were randomly divided into four experimental groups and treated with an intracanal medicament [calcium hydroxide (CH), double antibiotic paste (DAP), triple antibiotic paste (TAP), TAP with amoxicillin (mTAP)] and a non-treated control group. Medicaments were removed after three weeks, and ERRM was applied to all specimens. The coronal portion of each root was then sliced into 2-mm-thick parallel transverse sections (2 slices per tooth, n=20 slices per group), and a push-out test was used to measure the bond strength of ERRM to dentin. Data were analyzed using Bonferroni-corrected Mann-Whitney tests, with the level of significance set at p<0.05. RESULTS: The push-out bond strength of the CH group was significantly higher than that of the TAP, DAP and mTAP groups (p< 0.005). Furthermore, the bond strength of the control group was higher than the bond strength of both the DAP and mTAP groups. CONCLUSION: The use of CH in clinical practice may help improve the adhesion of ERRM to dentin.

Influence of Bleaching Regimen and Time Elapsed on Microtensile Bond Strength of Resin Composite to Enamel.

OBJECTIVES: The aim of this study was to evaluate the effects of time elapsed since bleaching and different bleaching regimens on the microtensile bond strength of resin composite to enamel. METHODOLOGY: Forty flattened buccal enamel surfaces were divided into four groups: An unbleached (control) group and three bleaching groups. Control group specimens were not subjected to a bleaching regimen (Group 1), while those in the bleaching groups were bleached as follows: opalescence 10% (Group 2), whiteness perfect 16% (Group 3), and whiteness hydrogen peroxide 35% (Group 4). Thereafter, the bleached specimens were divided into three subgroups (n = 4 teeth each) for restoration according to predetermined posttreatment time intervals (immediately, 1 week, and 2 weeks). Bonded specimens were then sectioned and subjected to µTBS testing. The data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests at α = 0.05. RESULTS: There was a significant difference in the µTBS of the resin composite to enamel in groups that were bonded immediately after bleaching and in the control group (P < 0.05). Compared to the control group, the µTBS in Groups 2, 3, and 4 decreased significantly 1-week postbleaching (P < 0.05). No significant difference in µTBS was observed between the bleached and unbleached groups 2 weeks after treatment (P > 0.05). CONCLUSIONS: Adhesive restorative procedures could not be performed immediately or after 1 week irrespective of the type or concentration of bleaching system used. Composite restorations on bleached enamel surfaces should be performed after an interval of at least 2 weeks.

Association of Toll-like receptors 2, 3, and 4 genes polymorphisms with periapical pathosis risk

BACKGROUND: The aim of this study was to investigate the role of gene variations of Toll-like receptors (TLR) 2, 3, and 4 on genetic susceptibility to periapical pathosis. MATERIAL AND METHODS: One hundred patients were included in the study and divided into two groups as follows; Control Group (n=50) that have root canal treatment and no periapical lesion, Patient Group (n=50) that have root canal treatment and periapical lesion. TLR2 Arg753Gln, TLR3 (c.1377C/T) and TLR4 Asp299Gly and Thr399Ile polymorphisms were genotyped by using PCR-RFLP. Genotypical analysis of control and patient groups were investigated to disclose whether there is any association between periapical lesions and gene variations. RESULTS: There are no significant statistical differences between control and patient groups according to TLR 2 and 4 gene sequence. On the contrary, CC allele detected 74% for TLR 3 in patient group, and this difference was found to be statistically significant (p < 0.005). CONCLUSIONS: According to these results, it can be suggested that patients with Toll-like receptor 3 gene polymorphisms could be susceptible to periapical pathosis

In vitro evaluation of the minimum bactericidal concentrations of different root-end filling materials.

AIM: The aim of this study was to evaluate the minimum bactericidal concentrations (MBC) of root-end filling materials ProRoot MTA, MTA Angelus and IRM. MATERIALS AND METHODS: Macrodilution broth method was used. Microorganisms used were: Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212) and Streptococcus mutans. Serial two-fold dilutions of root-end filling samples were prepared in macrodilution tubes with concentrations ranging from 1/2 to 1/512. The samples dilutions were incubated for 24 hours. After incubation, 0.1 ml of diluted culture was inoculated onto the surface of supplemented sheep blood agar (Merck, Germany) and all plates were incubated at 37°C in aerobic condition for 24 hours. The MBC was defined as the lowest concentration of root-end filling samples where no growth was recorded. RESULTS: MBC of both mineral trioxide aggregate (MTA) products against S. aureus were recorded as 15.62 mg/ml and for IRM 31.25 mg/ml MBC for both MTA groups against E. faecalis were recorded as 31.25 mg/ml and for IRM 62.5 mg/ml. MBC of all root-end filling samples against S. mutans were recorded as 62.5 mg/ml. CONCLUSION: All tested root-end filling materials showed acceptable MBC against S. aureus and E. faecalis. CLINICAL SIGNIFICANCE: All tested materials can be used safely for filling of a root-end cavity.

Influence of different drinks on the colour stability of dental resin composites.

OBJECTIVES: The objective of this study was to evaluate the discolouration effects of artificial saliva, granule lemon juice, coffee (without sugar), coca cola, sour cherry juice, fresh carrot juice and red wine on resin-based composite materials that are commonly used in restorative dentistry. METHODS: Colour of four brands of resin composites (Filtek Z 250 (3M Espe), Filtek Supreme (3M Espe), Quadrant (Cavex), Charisma (Heraeus-Kulzer)) of A2 shade was measured after one day of immersion in eight different solutions. Colour measurements were obtained by using a XL-20 Trismus Colourimeter and colour differences (DeltaE) were estimated. For statistical evaluation, analysis of variance (ANOVA), Dunnett and Tukey tests were used at a significance level of 0.05. RESULTS: For the four restorative materials tested, the lowest DeltaE values were observed in the artificial saliva, while DeltaE values were the highest in red wine group. When comparing the four different restorative materials, Filtek Supreme exhibited the least colour changes whereas Filtek Z250 was the least colour-stable. CONCLUSIONS: Dental resin composites and drinking solutions were significant factors that may affect the colour stability. After immersion for one day, all materials showed visible colour changes. The red wine solution exhibited more staining than others in three groups. Filtek Supreme showed significantly the least colour change due to its nano particle sizes.