Objectives: The aim of this study was to compare the shear bond strength (SBS) of
two different light sources under different thermal cycle frequencies.
Methods: Ninety human premolar teeth were divided into six groups, in which three
groups consisted of halogen groups – Group I was cured with halogen without thermocycle,
Group II cured with halogen with 500 thermocycles, and Group III cured with halogen
with 10,000 thermocycles. The other three groups consisted of Plasma arc (PAC) group
– Group IV was cured with PAC without thermocycle, Group V cured with PAC thermocycled
500 cycles, and Group VI cured with PAC thermocycled 10,000 cycles. Two way ANOVA
was used to compare the SBS between the groups, and chi squaretest was used to compare
the bond failure of ARI scores among the groups.
Results: A significant difference was found for curing lights (P<.001) and thermocycling
(P<.01). However, there was no interaction between light curing and thermocycling
(P=.177). The halogen groups demonstrated higher mean SBS than the PAC groups. Both
groups showed a significant reduction between no cycles and 10,000 cycles (P<.05).
Conclusions: Both light sources showed favorable SBS performance without the thermocycle
procedure. Thermocycling significantly decreased the SBS values of both groups. (Eur
J Dent 2010;4:257- 262)
Keywords
Shear bond strength - ARI score - Thermocycling - Halogen - Plasma arc
