Color Stability of Bioactive Restorative Materials After Immersion in Various Media.

Objectives: The aim of this article is to assess the color stability of the bioactive restorative materials (Activa Bioactive, Beautifil II) compared with the conventional resin composite and resin-modified glass ionomer cement after immersion in different staining solutions overtime. Materials and Methods: This is an in-vitro study that investigated four different material groups: (1) bioactive composite (ACTIVA Bioactive-Restorative, Pulpdent, USA), (2) Giomer composite (Beautifil II, SHOFU Dental GmbH, Japan), (3) resin-modified glass ionomer cement (Fuji II, GC Corporation, Japan), and (4) resin composite (Filtek Z350XT, 3M ESPE, USA). One hundred samples (n=25 each group) were fabricated using a custom acrylic mold (1 mm thick × 10 mm diameter) and then immersed in five different staining solution groups: coffee, black tea, cola, mixed berry juice, and saline. Baseline (T0) shade of samples was recorded using two spectrophotometers: VITA Easyshade Digital Advance and a spectrophotometer. Then shade was recorded at the intervals of 7 (T1), 14 (T2), and 28 (T3) days of immersion. Measurements were obtained and then ΔE was calculated for each group at each time point. Three-way analysis of variance tests were used to test the interactions between different variables at the 0.05 significance level. Results: All specimens showed a significant color change (P<0.001), following 7, 14, and 28 days of storage. Activa Bioactive and Filtek Z350 showed the highest color stability overtime in different staining solutions, whereas Fuji II and Beautifil II showed the least color stability. The most significant color change was noticed in the coffee group and then in the mixed berry juice group. Conclusion: Resin-based restorative materials showed higher color stability than glass ionomer-based restorations. Both spectrophotometers gave comparable results for materials' color stability.

Assessment of remineralisation potentials of bioactive dental composite using an in-vitro demineralised dentine model.

Objective: Minimally invasive dentistry encourages conservative caries excavation and remineralisation of the remaining dental tissues. However, dentine remineralisation is more difficult than enamel remineralisation due to the differences in their composition. This study aims to assess the remineralisation potential of Activa BioActive-Restorative and Beautifil II restoration on demineralised dentine samples, and compares it with glass-ionomer (GIC) restoration using energy dispersive X-ray (EDX) and Knoop hardness number (KHN). Methods: Non-carious extracted molar teeth were used, a total number of ten teeth were sectioned into halves and partially demineralised using 37.0% phosphoric acid for 60 s. All samples are assessed using EDX and KHN prior to restorations. The samples are then subdivided into four groups (n = 5). Group 1 was restored with Activa BioActive-Restorative, Group 2 received Beautifil II, Group 3 was restored with GIC, and the last group was used as a negative control. After storage, the samples were analysed using EDX and KHN. Results: The demineralisation protocol with 37.0% phosphoric acid significantly decreased the calcium:phosphate (Ca:P) ratio and KHN. Remineralisation occurred in all groups, but the highest percentage change in Ca:P ratio and KHN was observed in the Activa BioActive-Restorative group (20.7%, 82.0%, respectively), followed by the Beautifil II group, glass ionomer group, and the control group, in that order. Conclusion: Activa BioActive-Restorative restoration presents superior remineralisation compared to Beautifil II and glass-ionomer dental restorations.