| Full text | |
| Author(s): |
Rocha, M. G.
[1]
;
de Oliveira, D. C. R. S.
[1]
;
Sinhoreti, M. A. C.
[1]
;
Roulet, J. F.
[2]
;
Correr, A. B.
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Estadual Campinas, Piracicaba Dent Sch, Dept Restorat Dent, Piracicaba, SP - Brazil
[2] Univ Florida, Coll Dent, Dept Restorat Dent Sci, Gainesville, FL - USA
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Operative Dentistry; v. 44, n. 5, p. 499-509, SEP-OCT 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
Objectives: To evaluate the effect of combining camphorquinone (CQ) and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) on the depth of cure and polymerization shrinkage stress of bulk-fill composites. Methods and Materials: Experimental bulk-fill composites were produced containing equal molar concentrations of either CQ-amine or CQ-amine/TPO. The degree of in-depth conversion through each millimeter of a 4-mm-thick bulk-fill increment was evaluated by Fourier transform near-infrared microspectroscopy using a central longitudinal cross section of the increment of each bulk-fill composite (n=3). Light-transmittance of the multi-wave light-emitting diode (LED) emittance used for photoactivation (Bluephase G2, Ivoclar Vivadent) was recorded through every millimeter of each bulk-fill composite using spectrophotometry. The volumetric shrinkage and polymerization shrinkage stress were assessed using a mercury dilatometer and the Bioman, respectively. The flexural modulus was also assessed by a three-point bend test as a complementary test. Data were analyzed according to the different experimental designs (alpha=0.05 and beta=0.2). Results: Up to 1 mm in depth, adding TPO to CQ-based bulk-fill composites increased the degree of conversion, but beyond 1 mm no differences were found. The light-transmittance of either wavelengths emitted from the multi-wave LED (blue or violet) through the bulk-fill composites were only different up to 1 mm in depth, regardless of the photoinitiator system. Adding TPO to CQ-based bulk-fill composites did not affect volumetric shrinkage but did increase the flexural modulus and polymerization shrinkage stress. Conclusion: Adding TPO to CQ-based bulk-fill composites did not increase the depth of cure. However, it did increase the degree of conversion on the top of the restoration, increasing the polymerization shrinkage stress. (AU) | |
| FAPESP's process: | 17/22161-7 - Development and characterization of dental resin materials photoactivated under WAVELENGHS between 495 and 750 nm |
| Grantee: | Dayane Carvalho Ramos Salles de Oliveira |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 16/05823-3 - LOW INTENSITY LIGHT-CURING UNITS AND PHOTOINITIATION SYSTEMS ACTIVATED UNDER WAVELENGHS IN BETWEEN 495-750 NM FOR DENTAL RESIN MATERIALS |
| Grantee: | Dayane Carvalho Ramos Salles de Oliveira |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 17/22195-9 - Development and characterization of bulk fill composites light cured using silver nanoparticles surface plasmon resonance as a photoinitiator system |
| Grantee: | Mateus Garcia Rocha |
| Support Opportunities: | Scholarships abroad - Research Internship - Doctorate |