A comparison of the effects of incremental and snowplow techniques on the mechanical properties of composite restorations

Abstract

Background:Glass fibre-reinforced composite (GFRC) has the potential to enhance the mechanical properties of resin-based restorations. Nevertheless, the application technique can influence the cervical margin porosity, potentially reduc-ing the mechanical strength of restorations.Methods:In anin vitrosetup, mould specimens underwent six different treatments to assess the effects of snowplow andincremental curing techniques on the properties of GFRC (EverX) and universal resin composite (Filtek). Mechanicalproperties, namely flexural strength (FS), compressive strength (CS) and Vickers hardness (VH), were evaluated followingISO 4049 standards. Data interpretation utilized the Kruskal–Wallis tests.Results:No significant difference emerged across groups for FS. CS in the snowplow method with lesser EverX thickness(SnPl_1) was comparable with only EverX and Filtek (P>0.05). The CS was reduced in the snowplow technique withgreater EverX thickness (SnPl_2) (P<0.05) and further decreased with the incremental method (P<0.001). VH resultsshowed that EverX Posterior was consistently softer than Filtek, with specific patterns of hardness variations among dif-ferent application methods.Conclusions:Applying EverX and Filtek using the snowplow technique delivers superior CS and VH for restorations incontrast to the incremental method. Utilizing the snowplow approach in high-stress areas can make restorations morefracture-resistant.