Poster presented at the 3rd International Congress of CiiEM - Research and Innovation in Human and Health Sciences, Monte da Caparica, Portugal, 20-22 June 2018N/

Azul, A. C.

Polido, M.

Proença, L.

Santos, A.

English

Repositório Comum

DEPTH OF CURE OF BULK-FILL LIGHT CURED COMPOSITE  RESINS WITH DIFFERENT INITIATORS A. SANTOS1, L. PROENÇA1,2, M. POLIDO1,2, A. C. AZUL1,2  1 Instituto Universitário Egas Moniz, Caparica, Portugal; 2 Centro de Investigação Interdisciplinar Egas Moniz, Caparica, Portugal INTRODUCTION AND OBJECTIVES Bulk-fill composites’ manufacturers claim that these materials can be completely cured on a single layer up to 5mm (1), reducing the risk of bacterial and salivary contamination or air bubbles incorporation between layers (2) . The aim of this study was to o evaluate the depth of cure of bulk-fill composites with different times of curing, according to the pho-to initiator and the resin shade. MATERIALS AND METHODS Specimens were prepared incorporating an increment of composite (Tetric EvoCeram Bulk-Fill [TECBF] IVA and IVB - Ivoclar Viva-dent or Filtek One Bulk-Fill [FOBF] A3 and B1 - 3M ESPE – fig. 1) in standardized metal molds with 4 mm of diameter and height, using the buccal surface of a superior central incisor as a reflection substrate (fig. 2 and 3). Twelve groups (n=10) were defined ac-cording to curing time (10, 20 or 40 seconds), shade (lowest/highest value) and photo initiator (lucirin/camphoroquinone). Vickers microhardness (VMH) was measured at the top and bottom of each specimen by 5 indentations with a force of 29,42 N for 5 s (fig. 4 and 5). The depth of cure (DC) was obtained by the ratio of the bottom/top VHM (3). Results above 80% were used to consider-ate the sample well cured (4). Comparative inferential statistical analysis was performed through IBM SPSS Statistics  v.24 software using a three-way ANOVA at a significance level of 5%. RESULTS Regardless the shade, DC of the composite resins studied showed an improvement tendency with an increased polymerization time. In both of resins, time was the main factor in obtaining a suitable depth of cure (p<0.001 and partial eta squared = 0.771), being 10 s of polymerization insufficient to reach the minimum of 80% of polymerizati-on (p<0.001). So, 20 s is the time needed to ensure an adequate polymerization, since there is no statistically significant differences between 20 and 40 s of polymerization (fig 6). Colour was not found to be a significant factor in the DC of bulk-fill composites (p=0.916). FOBF showed a similar depth of cure but higher superficial hardness when compared to TECBF. Fig. 6—Depth of  cure of TECBF and FOBF according to their shade and curing time (%) DISCUSSION AND CONCLUSIONS Curing time is the crucial factor in obtaining a proper depth of cure. Colour, on the other hand, does not appear to be a significant factor in the depth of cure of the bulk-fill resin composites studied. The presence of different photo initiators may justify the diffe-rences found between the two resin composites. REFERENCES 1. Papadogiannis D, Tolidis K, Gerasimou P, Lakes R & Papadpgiannis Y. Viscoelastic properties, creep behavior and degree of conversion of bulk fill composite resins. Dental Materials. 2015; 31(12): 1533-1541. 2. Flury S, Hayoz S, Peutzfeldt A, Hϋsler J, Lussi A. Depth of cure of resin composites: Is the ISO 4049 method suitable for bulk fill materials?. Dental Materials. 2012; 28:521-528. 3. Standard I. 4049 Dentistry – Polymer-based restorative materials. International Organization for Standardization. 2009. 4. Moore B, Platt J, Borges G, Chu T, Katsilieri I. Depth of cure of dental composites: ISO 4049 depth and microhardness of types of materials and shades. Operative Dentistry. 2008, 33-4:408-4  Fig. 2—Diagram of specimens preparation  Fig. 1 A  - Composite TECBF; B—FOBF Fig. 3—Diagram of specimens polymerization Legenda da imagemFig. 5—Indentation Fig. 4—Vickers Hardness Tester Acknowledgements: The authors acknowledge Ivoclar for supplying the research materials 

Depth of cure of bulk-fill light cured composite resins with different initiators

https://comum.rcaap.pt/bitstream/10400.26/29025/1/Poster_AAzul_2018_02.pdf

Depth of cure of bulk-fill light cured composite resins with different initiators

Abstract

Similar works

Full text

Available Versions

Repositório Comum