TY - JOUR
T1 - Microhardness and flexural strength after chemical aging of chlorhexidine delivery systems based on acrylic resin
AU - Neves, Cristina Bettencourt
AU - Costa, Joana
AU - Nepomuceno, Luís
AU - Madeira, Ana
AU - Portugal, Jaime
AU - Bettencourt, Ana
N1 - Publisher Copyright:
© 2019 Sociedade Portguesa de Estomatologia e Medicina Dentaria. All rights reserved.
PY - 2019
Y1 - 2019
N2 - Objectives: To evaluate the effect of chlorhexidine incorporation on the microhardness and flexural strength of three reline acrylic resins, after a 28-day chemical aging process. Methods: Forty-eight specimens were fabricated according to the several possible combinations of acrylic reline resin and concentrations of incorporated chlorhexidine (Kooliner 0% vs. 2.5%; Ufi Gel Hard 0% vs. 5%; and Probase Cold 0% vs. 5%), to set 6 experimental groups (n=8). After a 4-week chemical aging process (pH fluctuation in artificial saliva, with cycles of 6 hours at pH=3 and 18 hours at pH=7), the Knoop microhardness (98.12 mN, 30 seconds) and flexural strength (1 kN, 5 mm/min) of all specimens were evaluated. Data were submitted to non-parametric statistical tests, according to Kruskal-Wallis and Mann-Whitney (α=0.05). Results: Chlorhexidine incorporation did not significantly affect the microhardness of the three tested resins (Kooliner p=0.798; Ufi Gel Hard p=0.798; and Probase Cold p=0.195). Although chlorhexidine incorporation did not influence the flexural strength of Kooliner (p=0.959) and Ufi Gel Hard (p=0.645), the incorporation of 5% chlorhexidine in Probase Cold led to a statistically lower flexural strength than that obtained without incorporation (p=0.021). Conclusion: After chemical aging, the microhardness of chlorhexidine-incorporated acrylic resins is not affected. However, the incorporation of 5% chlorhexidine into Probase Cold negatively affects its flexural strength. (Rev Port Estomatol Med Dent Cir Maxilofac. 2019;60(3):104-110) c 2019 Sociedade Portuguesa de Estomatologia e Medicina Dentaria.
AB - Objectives: To evaluate the effect of chlorhexidine incorporation on the microhardness and flexural strength of three reline acrylic resins, after a 28-day chemical aging process. Methods: Forty-eight specimens were fabricated according to the several possible combinations of acrylic reline resin and concentrations of incorporated chlorhexidine (Kooliner 0% vs. 2.5%; Ufi Gel Hard 0% vs. 5%; and Probase Cold 0% vs. 5%), to set 6 experimental groups (n=8). After a 4-week chemical aging process (pH fluctuation in artificial saliva, with cycles of 6 hours at pH=3 and 18 hours at pH=7), the Knoop microhardness (98.12 mN, 30 seconds) and flexural strength (1 kN, 5 mm/min) of all specimens were evaluated. Data were submitted to non-parametric statistical tests, according to Kruskal-Wallis and Mann-Whitney (α=0.05). Results: Chlorhexidine incorporation did not significantly affect the microhardness of the three tested resins (Kooliner p=0.798; Ufi Gel Hard p=0.798; and Probase Cold p=0.195). Although chlorhexidine incorporation did not influence the flexural strength of Kooliner (p=0.959) and Ufi Gel Hard (p=0.645), the incorporation of 5% chlorhexidine in Probase Cold led to a statistically lower flexural strength than that obtained without incorporation (p=0.021). Conclusion: After chemical aging, the microhardness of chlorhexidine-incorporated acrylic resins is not affected. However, the incorporation of 5% chlorhexidine into Probase Cold negatively affects its flexural strength. (Rev Port Estomatol Med Dent Cir Maxilofac. 2019;60(3):104-110) c 2019 Sociedade Portuguesa de Estomatologia e Medicina Dentaria.
KW - Acrylic resins
KW - Chlorhexidine
KW - Denture relining
KW - Denture stomatitis
KW - Flexural strength
KW - Hardness
UR - http://www.scopus.com/inward/record.url?scp=85078353058&partnerID=8YFLogxK
U2 - 10.24873/J.RPEMD.2019.10.458
DO - 10.24873/J.RPEMD.2019.10.458
M3 - Article
AN - SCOPUS:85078353058
SN - 1646-2890
VL - 60
SP - 104
EP - 110
JO - Revista Portuguesa de Estomatologia, Medicina Dentaria e Cirurgia Maxilofacial
JF - Revista Portuguesa de Estomatologia, Medicina Dentaria e Cirurgia Maxilofacial
IS - 3
ER -