Abstract:

Objectives: The disinfection of fabricated prostheses is crucial to prevent crossinfection
between dental laboratories and clinics. However, there is a lack of information
about the effects of chemical disinfection on 3D-printed denture base resins. This study
aimed to evaluate the impact of different disinfectants on the flexural strength, elastic
modulus, micro-hardness, surface roughness (Ra), and change in color of 3D-printed and
conventional heat-polymerized (HP) denture base resins (DBRs).

Methods: A total of
240 specimens (80 bar-shaped (64 × 10 × 3.3 mm) and 160 disk-shaped (10 × 2 mm))
were made from HP and 3D-printed DBRs. For each resin, the specimens were divided
into four groups (n = 10) according to the disinfectant solution. One remained in water
without disinfection as a control group, while the other three groups were disinfected
using 1% sodium hypochlorite, 2% glutaraldehyde, or 10% Micro 10+ for 30 min. The
flexural strength, elastic modulus, micro-hardness, Ra, and color change were measured.
The collected data were statistically analyzed using a two-way ANOVA and Tukey’s post
hoc test (α = 0.05).

Results: A significant decrease in flexural strength, elastic modulus, and
hardness was found with sodium hypochlorite (p < 0.05). When comparing the resins per
solution, the 3D-printed resin showed a significant decrease in flexural strength, elastic
modulus, and hardness compared with PMMA (p < 0.001), while no change was found in
the Ra of both resins with all disinfectants (p > 0.05). Disinfecting with sodium hypochlorite
resulted in a significant increase in color change for both resins (p < 0.05); however, all the
changes were within clinically acceptable limits. Sodium hypochlorite showed the highest
color change, while 2% glutaraldehyde and 10% Micro 10+ showed no significant changes
in the tested properties (p > 0.05).

Conclusions: Neither resin showed a change in surface
roughness with immersion in disinfectants. Sodium hypochlorite had an adverse effect on