27 research outputs found
Investigating the impact of whitening toothpastes on bioactive resin-based restorative materials: a comparative analysis
Abstract Objective To assess the color stability and surface roughness of bioactive resin-based composite following exposure to coffee staining and brushing with whitening toothpastes. Methods Disk-shaped specimens of Filtek Z250 (FZ), Beautifil Flow Plus (BFP), Activa Presto (AP), and Fuji II LC (FII) were stained with coffee and then brushed with one of three toothpastes, conventional (C-TP), non-peroxide whitening (W-TP) or hydrogen peroxide-containing whitening toothpaste (HPW-TP) for 10 000 cycles. Changes in color (ΔE00) and surface roughness were measured. Results Two-way ANOVA revealed a significant interaction between restorative material and toothpaste type in roughness (p = 0.049) and ΔE00 (p = 0.007). FII consistently had the highest surface roughness change across all toothpastes, and AP showed significantly higher value than BFP and FZ with C-TP and W-TP (p 0.05). Additionally, the effect of toothpaste type on individual parameters, as well as the interaction between material and toothpaste type, was nonsignificant (p > 0.05). Conclusion All materials tested showed increased roughness and unacceptable staining with none returning to baseline color or achieving acceptable color change post toothbrushing, irrespective of toothpaste type. Clinical significance Understanding the effects of staining and whitening toothpastes on bioactive resin-based composites is important for optimizing material selection and maintenance protocols to ensure long-lasting esthetic outcomes in patients prone to staining
Comparative Evaluation of Color Stability in Bioactive and Conventional Resin Cements Under Thermal Stress Conditions
Bioactive resin-based cements (RBCs) were recently introduced, but data on their color stability remain limited. This study analyzed the impact of thermal cycling on the color and whiteness of bioactive RBCs. Specimens (n = 10) were fabricated from Panavia SA Universal (PN), Predicta Bioactive Cement (PR), and ACTIVA BioACTIVE cement (AC). CIE Lab* values were registered at baseline and after 5000, 10,000, and 15,000 thermal cycles (5–55 °C). Changes in color (ΔE00) and whiteness index (ΔWID) were calculated and compared. Material type and thermal cycling significantly affected ΔE00 and ΔWID (p < 0.001). AC showed the highest ΔE00 values at all stages (p < 0.001), with a progressive increase over time. PN differed significantly between early and later cycles (p < 0.05), while PR remained stable (p > 0.05). Analysis of color parameters indicated that AC underwent the most pronounced changes, particularly in Δa and Δb, while PN exhibited the greatest shift in Δb. For ΔWID, PR had significantly lower values than PN (p < 0.05) and AC (p < 0.001), with no difference between PN and AC (p > 0.05), and thermal cycling significantly affected all groups, with PR and AC differing across all stages (p < 0.05). Thermal cycling significantly influenced the color stability and whiteness of bioactive RBCs, with AC exhibiting the greatest changes over time, while PR demonstrated superior stability
Comparative analysis of finishing and polishing procedures on gloss and color stability in bioactive dental resin composites
Objective . The aim of this study was to assess the effect of different polishing systems on the color stability of bioactive dental resin composites compared to a conventional composite. Materials and Methods . Two different bioactive dental resin composites (Beautifil Flow Plus F00 and Activa Presto) along with a nanohybrid composite (Filtek Z250 XT) were tested. A total of 20 samples per material were prepared and divided into four groups as per polishing protocol: Sof-Lex Diamond, Jiffy and TorVm polishing systems as well as a control group without polishing. A spectrophotometer was used to measure the color parameters before and after immersion in a coffee solution for 12 days. The color change (ΔE _00 ) was calculated after immersion for each sample. Gloss was also measured at baseline and post immersion using a gloss meter. Results . There was a significant change in both ΔE _00 and gloss in all materials (p < 0.05). Z250 XT exhibited better color stability and gloss retention, particularly with the Jiffy system. Beautifil Flow Plus F00 demonstrated acceptable color stability and high gloss with the TorVm discs. Activa Presto showed significant color changes across all polishing systems. Conclusions . This work highlights the importance of understanding the effect of polishing systems on dental resin composites for optimal aesthetic outcomes. Despite the obvious benefits of bioactivity in both Beautifil Flow Plus F00 and Activa Presto, their performance regarding both color stability and gloss retention was lower than the inert Z250 XT. These findings emphasize the need for careful material and technique selection in clinical practice to ensure the longevity and esthetic quality of dental restorations
Surface roughness and gloss retention of bioactive resin composite after simulated toothbrush abrasion
Background. Newly introduced bioactive resin composites are being used more often. Few studies have evaluated the influence of toothbrush abrasion on their surface characteristics. Methods. This study aims to assess the surface roughness (Ra) and gloss values (GU) of 3 bioactive composites and a conventional nanohybrid composite before and after simulated toothbrush abrasion. Five samples each of Filtek Z250 XT, Beautifil Flow Plus, Activa Presto and Predicta Bioactive Bulk were subjected to 10,000 cycles of simulated toothbrush abrasion. Ra and GU values were evaluated at baseline and after each 2,500 cycles. Results. Significant difference was found in both Ra and GU (P 0.05). After 7,500 cycles, the mean Ra value of Activa Presto at 0.64 (0.14) was significantly higher than that of Z250 XT at 0.49 (0.03) (P < 0.001). At 10,000 cycles, Activa Presto had significantly higher Ra at 0.70 (0.10) when compared to Z250 XT at 0.52 (0.08), Beautifil Flow Plus at 0.56 (0.07) and Predicta Bioactive Bulk at 0.59 (0.10) (P < 0.001). Conclusion. All materials showed an increase in Ra and decrease in GU after simulated toothbrushing
Influence of chlorhexidine dentin disinfection on universal adhesive performance: Interfacial adaptation and bond strength assessments.
PurposeThis study aimed to investigate the effect of chlorhexidine (CHX) cavity disinfectant on interfacial microleakage and micro-tensile bond strength (μTBS) of a universal adhesive bonded to dentin in both self-etch (SE) and etch-and-rinse (ER) modes.MethodsClass I cavities were prepared in the coronal dentin of extracted human teeth and assigned to two etching modes (SE or ER), then subdivided by disinfection with or without CHX (n = 5). Cavities were restored using Single Bond Universal Adhesive and Filtek Z350 XT composite. After 10,000 thermal cycles, interfacial microleakage was assessed on serial B-scans obtained for each specimen using cross-polarization optical coherence tomography. For μTBS testing, resin composite was bonded to dentin discs, sectioned into beams, and subjected to tensile load until failure using a universal testing machine. Failure modes in fractured beams were analyzed under a stereomicroscope and categorized as adhesive, cohesive, or mixed. ANOVA with Bonferroni post-hoc at a significance level of 0.05 was used to compare the groups.ResultsMicroleakage was not significantly influenced by the etching mode or CHX disinfection (p-value = 0.068). For μTBS, the ER group exhibited the highest values, and CHX disinfection did not significantly alter these results (p-value = 1.000). In contrast, the SE-CHX group displayed significantly lower μTBS than the ER, ER-CHX, and SE groups (p-values of ConclusionThe use of CHX disinfectant influences the bonding performance of universal adhesive differently depending on the application mode. Specifically, in the SE mode, CHX adversely affects bond strength to dentin. This suggests that when using universal adhesives in SE mode, clinicians should carefully consider the use of CHX disinfectants, as they may interfere with the adhesive's effectiveness
Effect of Antibacterial Agents on Dentin Bond Strength of Bioactive Restorative Materials
Treating dentin surfaces with antibacterial agents prior to bonding bioactive restorations might affect their mechanical properties. In this study, we evaluated the effect of silver diamine fluoride (SDF) and chlorhexidine (CHX) on the shear bond strength (SBS) of bioactive restorative materials. Dentin discs were treated with SDF for 60 s or CHX for 20 s and bonded with four restorative materials, namely Activa Bioactive Restorative (AB), Beautifil II (BF), Fuji II LC (FJ), and Surefil One (SO). Control discs were bonded without treatment (n = 10). SBS was determined using a universal testing machine, and a scanning electron microscope (SEM) was used for the evaluation of the failure mode and the cross-sectional examination of adhesive interfaces. The SBS of each material between different treatments and of the different materials within each treatment were compared via a Kruskal–Wallis test. The SBS of AB and BF was significantly higher than that of FJ and SO in the control and CHX groups (p < 0.01). In the latter, SBS was higher in FJ than SO (p < 0.01). SO had a higher value with SDF compared to CHX (p = 0.01). The SBS of SDF-treated FJ was higher than that of the control (p < 0.01). SEM showed a more homogenous and improved interface of FJ and SO with SDF. Neither CHX nor SDF compromised the dentin bonding of bioactive restorative materials
Spontaneous regression of pineal region arachnoid cyst: A case report and review of literature
Arachnoid cyst is a rare benign cerebrospinal fluid-filled cyst that can develop anywhere in the brain along the arachnoid membrane and usually unaccompanied by the anomalous development of the brain structure. These cysts are usually located in the middle cranial fossa. However, they are also denoted in other regions. Arachnoid cysts are mostly asymptomatic and diagnosed incidentally. Spontaneous regression of arachnoid cysts in different anatomical regions of the brain has been reported in the literature. However, to the best of our knowledge, this is the first case reporting an unusual spontaneous regression of arachnoid cyst in the pineal region in a 3-year-old child presented to our hospital with hydrocephalus without alarming signs and was treated conservatively as the patient was stable, and the cyst showed spontaneous regression. A comprehensive review of the literature regarding spontaneous regression of arachnoid cysts has been collected and discussed in this article.</jats:p
