Influence of soft-start curing protocol in the degree of conversion of a nanohybrid resin composite

Heloisa Amorim Periotto, Ana Daielly da Silva, Isabella Saraiva Leão de Resende, Hellen Martins Jucá, Sérgio Lima Santiago, Jiovanne Rabelo Neri


OBJECTIVE: To analyze the influence of the soft-start curing protocol in the degree of conversion of a nanohybrid composite.
METHODS: Ten specimens were prepared from the polymerization of the composite resin Llis using two protocols: conventional (1000 mW/cm² for 20 seconds) or gradual (250 mW/cm² for 20 seconds + 1000 mW/cm² for 15 seconds). Then, analyzes were performed using a spectrophotometer and data were subjected to Two-way ANOVA and Holm-Sidak test. The significance level was 5%.
RESULTS: There was no statistical difference between the average resin conversion degree of composite values in the base area and top for both curing protocols (p > 0.05).
CONCLUSION: Therefore, the use of soft-start curing protocol did not interfere in the degree of conversion of a nanohybrid composite.


composite resins; polymerization; physical properties.

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