This study assessed the shear bond strength (SBS) and failure modes of lithium disilicate ceramic veneering material to different high-performance polymers. Thirty-six square specimens measuring 7 × 7 × 2 ± 0.05 mm were prepared from pure polyetheretherketone (PEEK), Bio-high performance PEEK (BioHPP) and Trilor discs. Polymer specimens were air-borne abraded utilizing aluminum oxide particles, cleaned, and a bonding agent was applied (visio. link). The veneering LDC material (3 × 2 mm) was milled, hydrofluoric acid etched (9.5%) and primed (Clearfil ceramic). The LDC was bonded to the polymer specimens using dual-cured resin cement (Panavia V5) and light polymerized. The bonded specimens were subjected to 5000 cycles of physiological aging by thermocycling, and the SBS test was performed in a universal testing machine at 0.5 mm/min cross-head speed. The debonded specimens were analyzed to determine the primary bond failure sites (adhesive, mixed or cohesive). Data analysis was performed using one-way ANOVA and a post hoc Tukey test (α ≤ 0.05). The BioHPP material demonstrated the highest SBS values (23.94 ± 1.43 MPa), and the Trilor group recorded the lowest SBS values (17.09 ± 1.07 MPa). The PEEK group showed a mean SBS of 21.21 ± 1.51 MPa. The SBS comparison showed significant variations across all material groups (p < 0.001). Regarding failure modes, adhesive failure was observed in 40% of BioHPP and PEEK specimens and 90% of Trilor specimens. The cohesive failure occurred in 50% of PEEK and 30% of BioHPP specimens, while the Trilor specimens showed no cohesive failure. Mixed failures were reported in 30% of BioHPP and 10% of PEEK and Trilor specimens. The BioHPP material demonstrated high SBS followed by PEEK and Trilor. The SBS between the tested materials was statistically significant. However, the SBS of the tested implant framework materials was above the limit stipulated by the ISO 10477 standard (5 MPa) and the clinically acceptable range of 10–12 MPa.

Background/Objectives: Root canal treatment (RCT) is a crucial procedure for preserving dental health. While its clinical success rates are well documented, patient-reported outcomes regarding quality of life remain less explored. This study aimed to assess the long-term impact of RCT performed in an educational hospital on patients’ oral-health-related quality of life (OHRQoL) using the Oral Health Impact Profile-14 (OHIP-14). Methods: A total of 1500 patients who underwent non-surgical RCT between April 2018 and February 2023 were called and invited for a follow-up visit. During the visit, all teeth that had undergone RCT were assessed clinically and radiographically by two calibrated examiners to evaluate RCT quality and pre- and post-treatment periapical index (PAI) scores. Demographic information and OHIP-14 responses were collected, and the data were recorded. Results: Patients reported high levels of satisfaction (95%) and no negative impact on their OHRQoL. Statistical analysis revealed that post-operative periapical index (PAI) scores (p < 0.001), patient gender (p = 0.003) and nationality (p = 0.029) significantly influenced OHRQoL perceptions; Conclusion: These findings emphasize the effectiveness of RCT in enhancing patients’ quality of life and highlight the impact of demographic factors—such as gender and whether the patient is a resident or a national of the country, along with post-treatment severity of the disease—on patient-reported outcomes.