Mechanical and antimicrobial property of different surface treated glass ionomer cements under desiccated condition

Abstract

Background: The purpose of this in vitro study was to evaluate the effect of five different surface
treatments on the mechanical property and antimicrobial effect of three desiccated glass ionomer
cements.
Materials and Methods: In this in vitro experimental study, 300 rectangular blocks of three
different restorative materials were fabricated using an aluminum mold, Group I (n = 100) Micron
bioactive, Group II (n = 100) GC Fuji IX GP Extra, and Group III (n = 100) bioglass R. These blocks
were stored in 100% humidity for 24 h and then placed in air to desiccate for another 24 h. These
groups were further divided into two major groups (n = 50) for both mechanical (Flexural) and
antimicrobial testing. The blocks of mechanical and antimicrobial groups were further divided into
five subgroups (n = 10) based on the medias used for surface treatment (senquelNaF, MI varnish,
chlorhex plus, kedodent mouthwash, and 100% humidity [control]). Flexural strength (FS) was
measured using the universal testing machine. Fracture strength of groups was compared using the
one‑way analysis of variance and Tukey’s post hoc test with P ≤ 0.05 considered statistically significant.
Antimicrobial effect was carried out by covering the specimens in a suspension of Streptococcus
mutans followed by incubation for 24 h. The blocks were later washed, vortex mixed, serially
diluted, and plated. Ccolony‑forming unit/ml was calculated after 3 days of incubation. Data were
then analyzed using the Kruskal–Wallis and Mann–Whitney U nonparametric test, with P ≤ 0.05
considered statistically significant.
Results: Micron bioactive with the surface treatment of MI varnish significantly exhibited highest
FS. Surface treatment of desiccated restorative materials with chlorhex plus exhibited no growth
of S. mutans. GC Fuji IX GP Extra with surface treatment of MI varnish exhibited highest reduction
in S. mutans growth compared to other experimental group.
Conclusion: Surface treatment of restorative material with MI varnish improved their mechanical
and antimicrobial property while among three restorative materials Micron bioactive showed
better mechanical property, whereas GC Fuji IX GP Extra exhibited better antimicrobial property.
Key Words: Desiccation, flexural strength, glass‑ionomer cements