Vickers hardness and shrinkage stress evaluation of low and high viscosity bulk-fill resin composite
| Autor: | Massimo Carossa, Tatjana Maravic, Milena Cadenaro, Lorenzo Breschi, Annalisa Mazzoni, Allegra Comba, Nicola Scotti |
|---|---|
| Přispěvatelé: | Comba A., Scotti N., Maravic T., Mazzoni A., Carossa M., Breschi L., Cadenaro M., Comba, A., Scotti, N., Maravic, T., Mazzoni, A., Carossa, M., Breschi, L., Cadenaro, M. |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Polymers and Plastics Composite number Bulk fill Bulk-fill composite 02 engineering and technology medicine.disease_cause Indentation hardness Article Stress (mechanics) lcsh:QD241-441 03 medical and health sciences 0302 clinical medicine Composite resin lcsh:Organic chemistry Mold medicine Irradiation Composite material Shrinkage composite resins Shrinkage stress Microhardne 030206 dentistry General Chemistry 021001 nanoscience & nanotechnology Vickers hardness test Composite resins Microhardness microhardness 0210 nano-technology |
| Zdroj: | Polymers, Vol 12, Iss 1477, p 1477 (2020) Polymers Volume 12 Issue 7 |
| Popis: | The aim of this in vitro study was to evaluate the hardness and shrinkage stress (SS) of six bulk-fill resin composites. To evaluate microhardness (MH), ten 6 mm specimens were prepared using a metal mold for each selected bulk-fill resin composite and irradiated from the top side for 40 s using an LED light. After 24 hours of storage, Vickers MH was evaluated on the upper, lower and lateral sides of the specimens. SS evaluation was then performed with a universal machine, which evaluated the contraction force generated by a bulk-fill composite specimen placed between two metal cylinders during and after light curing. The results were evaluated with a one-way ANOVA test with a post-hoc Bonferroni test and linear regression analysis (p < 0.05). All materials showed a significant MH decrease between the top and bottom surfaces. However, the bulk-fill materials tested performed differently when considering lateral depth progression. ANOVA tests for SS evaluation showed that both SDR and Venus Bulk Fill had significantly lower stress during irradiation than other tested materials. Further, MH decrease became significantly lower from the top surface at different depths in each tested group. Among the different resins, Venus Bulk Fill and SDR showed not only inferior hardness, but also a significant reduction in SS. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|