Erbium-Doped Yttrium Aluminum Garnet Laser and Photochemical Functionalization of Polyetheretherketone Post Surface: Comparative Push-Out Bond Strength Evaluation Using Total-Etch and Self-Adhesive Resin Cements

Abstract

Aim:

Evaluating the effect of surface conditioning protocols—sulfuric acid (SA), Er: YAG (erbium-doped yttrium aluminum garnet) laser, and Rose Bengal-activated photochemical functionalization (RB-PCF)—on the surface roughness (R_a) and push-out bond strength (PBS) of polyetheretherketone (PEEK) posts bonded to canal dentin using total-etch conventional resin cement (TE-CRC) and self-adhesive resin cement (SARC).

Material and Method:

Briefly, 60 extracted, caries-free human maxillary canines were decoronated to 15 mm root length. Endodontic therapy was performed using the ProTaper Next system, followed by obturation. Post space preparation was carried out with Peeso reamers. Briefly, 90 PEEK posts were allocated into 3 groups (n = 30) based on the surface conditioning methods. Group 1: SA, Group 2: Er: YAG laser, Group 3: RB-PCF. R_a was assessed using a profilometer, and surface topography was evaluated by scanning electron microscopy. The remaining 20 posts were subdivided based on the cement type used for bonding to canal dentin: TE-CRC and SARC (n = 10 each). Specimens were sectioned into cervical, middle, and apical thirds and tested for PBS, after which failure modes were examined. Data analysis was performed using analysis of variance and post hoc Tukey (p < 0.05).

Results:

Group 1 (SA) showed the highest R_a (1.32 ± 0.32 µm), while Group 3 (RB-PCF) exhibited the lowest R_a (0.56 ± 0.21 µm). The highest PBS was observed in the cervical third of Group 1A (SA + TE-CRC), whereas the lowest occurred in the apical third of Group 3A (RB-PCF + TE-CRC).

Conclusion:

Er: YAG laser conditioning appears to be a viable alternative to SA for surface pretreatment of PEEK posts. Self etch resin cement showed improved performance compared with TE-CRC.