Styrene-butadiene-styrene addition improves the properties of asphalt in surface dressing: the thermal susceptibility is reduced and the binder cohesion increased, hence better resistance to bleeding and to aggregate dislodgement. The characteristics of hot-applied and emulsified SBS-modified binders are compared through series of laboratory tests: rheological properties, cohesion, tensile strength, toughness and tenacity. Application problems and field performance are globally examined. Hot-applied SBS-modified binders encounter viscosity and adhesion problems. They require a high amount of diluent, that may soften the support and cause aggregate embedment. Their SBS-content must be limited. Emulsified SBS-modified asphalts show excellent adhesion to all types of aggregate. They require very small amounts of diluent. High SBS contents can be employed. Their main drawback is slow setting time.

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Aim: This study assessed the effect of thermal aging on the interfacial strength of resin cements to surface-treated PEEK. Methods: Ninety-six PEEK blocks were allocated into 4 groups (n=24), according to following surface treatments: SB - sandblasting with aluminum oxide; SA - acid etched with 98% sulfuric acid; CA – coupling agent (Visio.link, Bredent) and CO - control group (untreated). Surface roughness (Ra) was measured and one cylinder (1-mm diameter and height) of Rely-X Ultimate - ULT (3M/ESPE) and another one of Panavia V5 - PAN (Kuraray) were constructed on the treated or untreated PEEK surfaces. Half of the samples of each group were thermal aged (1,000 cycles). Samples were tested at a crosshead speed of 1 mm/min in shear mode (μSBS). Ra and μSBS data were compared using one- and three-way ANOVA, respectively, and Tukey’s tests. Results: SA and SB samples had the roughest surfaces, while CA the smoother (p<0.001). Thermal aging reduced μSBS regardless the surface treatment and resin cement used. There was interaction between surface treatment and resin cement (p <0.001), with ULT showing higher μSBS values than PAN. SA provided higher μSBS than SB for both resin cements, while for CA μSBS was higher (PAN) or lower than SB (ULT). Conclusion: Aging inadvertently reduces interfacial strength between PEEK and the resin cements. If ULT is the resin cement of choice, reliable interfacial strength is reached after any PEEK surface treatment. However, if PAN is going to be used only SA and CA are recommended as PEEK treatment.