Flexural Properties and Elastic Modulus of Different Esthetic Restorative Materials: Evaluation after Exposure to Acidic Drink

Abstract

Background. Acidic beverages, such as soft drinks, can produce erosion of resin composites. The purpose of the present study was to investigate mechanical properties of different esthetic restorative materials after exposure to acidic drink. Methods. Nine different composites were tested: nanofilled (Filtek Supreme XTE, 3M ESPE), microfilled hybrid (G-ænial, GC Corporation), nanohybrid Ormocer (Admira Fusion, Voco), microfilled (Gradia Direct, GC Corporation), microfilled hybrid (Essentia, GC Corporation), nanoceramic (Ceram.X Universal, Dentsply De Trey), supranano spherical hybrid (Estelite Asteria, Tokuyama Dental Corporation), flowable microfilled hybrid (Gradia Direct Flo, GC Corporation), and bulk fill flowable (SureFil SDR flow, Dentsply De Trey). Thirty specimens of each esthetic restorative material were divided into 3 subgroups (n=10): specimens of subgroup 1 were used as control, specimens of subgroup 2 were immersed in 50 ml of Coca Cola for 1 week, and specimens of subgroup 3 were immersed in 50 ml of Coca Cola for 1 month. Flexural strength and elastic modulus were measured for each material with an Instron Universal Testing Machine. Data were submitted to statistical analysis. Results. After distilled water immersion, nanofilled composite showed the highest value of both flexural strength and elastic modulus, but its flexural values decreased after acidic drink immersion. No significant differences were reported between distilled water and acidic drink immersion for all other materials tested both for flexural and for elastic modulus values. Conclusions. Even if nanofilled composite showed highest results, acidic drink immersion significantly reduced flexural values.

New Resin-Based Bulk-Fill Composites: in vitro Evaluation of Micro-Hardness and Depth of Cure as Infection Risk Indexes

“…Based on the importance of enamel and bone hardness, since bacteria takes advantage of micro-alterations [46], a decrease of the material's hardness following the erosive action of acids might also be responsible for bacterial colonization. The biofilm accumulated over the restoration produces acidic substances, which further cause a surface degradation with the subsequent softening and roughening of the material's surface [46,47]. Finally, a greater penetration of microorganisms through the fissure interposed between the restoration and the enamel may occur, resulting in the re-infection of the tooth (secondary caries) [48][49][50].…”

Influence of Filler Loading on the Mechanical Properties of Flowable Resin Composites

“…Only Filtek Supreme XT (A3) demonstrated spherical inorganic filler (Figure 6b). The nano-and microhybrid fillers showed high particle packing with a relatively low viscosity, improving workability, mechanical properties, and polish retention [33][34][35].…”

Glass Fiber Reinforced Composite Orthodontic Retainer: In Vitro Effect of Tooth Brushing on the Surface Wear and Mechanical Properties

“…The middle point of the machine was moved using a computer-controlled stepper motor, the force was recorded by electronic sensors, and the position of the middle point of the machine was associated with the passive position. The flexural strength values were recorded with the Nexygen MT software (Lloyd Instruments) [31].…”