The Influence of Silica Dioxide and Aluminum Oxide Nano Fillers Reinforced Heat Cured Acrylic Denture Base Material and Thermocycling on Tensile and Shear Bond to Denture Soft Lining Material

Abstract

Background: Soft lining materials play an important role in modern prosthodontics
treatment because of their capability to restore the inflamed and distorted mucosa.
The purpose of the research was to estimate the influence of acrylic denture base
reinforcement with silanted nano fillers (Al2O3 and Sio2) separately on tensile and
shear bond strength of soft lining material and studying effect of thermo cycling
on bonding strength.
Materials and methods: Total 120 specimens were prepared; it divided into 60
Specimens for shear bond strength test and 6o specimens for tensile bond strength
test. Specimens were sub grouped into 30 Specimens without thermo cycling and
30 specimens with thermo cycling. Each sub group is consisted from: 10
Specimens control, 10 specimens were reinforced with 2 wt% of Al2O3 nano fillers
and 10 specimens were reinforced with 5 wt% of SiO2 nano fillers. Samples were
processed depending on test applied. Soft lining material was applied for each
testing group. Samples were immersed in distal water for 24 hours at 37°C before
testing. For thermo cycling test, specimen were thermo cycled in thermo cycling
device. Bonding strength test was done using INSTRON universal testing
machine.
Results: reinforcement of acrylic denture base with nano-fillers was significantly
increase both tensile and shear bonding of lining material and thermo cycling
decreases both bonding strength.
Conclusion: reinforcement of acrylic denture base with nano fillers could improve
bonding strength of lining material, while thermo cycling had a deleterious effect
on bonding strength.