Evaluation of surface roughness and cell viability of milled and printed polyetheretherketone healing abutments: a comparative study.

This study aimed to evaluate and to compare the cell viability and surface roughness characteristics of subtractively manufactured polyetheretherketone (PEEK), additively manufactured PEEK, and titanium healing abutments. The specimens were fabricated from three different materials: milled titanium (MT; control group), milled polyetheretherketone (MP; subtractively manufactured), and 3D-printed polyetheretherketone (PP; additively manufactured). Ten discs were produced for each group (n = 10). The surface roughness (Ra) was measured using a contact profilometer, and the surface topography was analyzed using scanning electron microscopy (SEM). Human gingival fibroblasts (HGFs) were cultured on the discs, and cell viability was assessed using an MTT assay at 48 h. Data were analyzed using one-way ANOVA and Tukey's post-hoc test (α = 0.05). Ra values were significantly different among the groups (p = 0.023), with PP (1.03 ± 0.52) showing the highest Ra, followed by MP (0.51 ± 0.17) and MT (0.37 ± 0.21). The SEM analysis revealed distinct surface morphologies for each material. Cell viability was highest in the PP group, with statistically significant differences compared with both MP and MT groups (both p = 0.002). The material-manufacturing combinations affects the surface roughness and cell viability of the PEEK healing abutments. Biocompatibility may depend more on material composition and surface properties than on roughness alone. Additively manufactured PEEK could serve as a promising alternative to titanium, owing to its favorable biological response. Further studies are needed to evaluate the long-term clinical performance of these materials and their effects on peri-implant soft tissue healing and regeneration.