Date of Award
Spring 2019
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Thompson, Geoffrey A.
Second Advisor
Drago, Carl
Third Advisor
Rasoulianboroujeni, Morteza
Abstract
Objective: Soft tissue attachment to different surfaces plays a pivotal role in long term success of dental implants. The aim of the current study was to evaluate viability and adhestion of human gingival fibroblasts (HGFs) upon specific surface modifications on different implant abutment materials. Material & Methods: A total of 150 specimens in 6 experimental groups were used: titanium alloy (Ti [smooth machined]), titanium laser-modified (TiL), PEEK (P [smooth machined]), PEEK laser-modified (PL), PEEK plasma treated (PP), PEEK laser and Plasma treated (PLP). The surface roughness (Sa), water contact angle (WCA), and X-ray photoelectron spectroscopy (XPS) were measured. Human gingival fibroblast (HGF) attachment and proliferation were observed 1, 3 and 7 days post cell seeding. Results: Sa values of the laser modified groups were significantly higher than the non-modified (smooth machined) groups (P<.001). WCA of all groups was greater than 40 degrees, except for the plasma treated groups. XPS analysis of both Ti and PEEK groups showed that this laser treatment did not alter chemical bonding. Scanning Electron Microscopy (SEM) revealed more functionally oriented HGF cells on the laser-grooved surfaces; however, the cells on the laser-modified PEEK groups were more stretched compared to the TiL group. On the first, third, and seventh day of proliferation, titanium groups showed no significant differences (P>.05). On the first and third day of proliferation, the plasma treated PEEK groups showed significantly greater proliferation than all experimental groups (P < .001); the PL group had the lowest proliferation (P < .001). On the seventh day of proliferation, statistically significant differences were observed among all groups (P < .001), with the exception of PL & P groups and PP & PLP groups(P>.05). Conclusion: Within the limitations of this study, laser modified titanium and PEEK surfaces led to guided gingival fibroblast attachment. Plasma treatment of PEEK surfaces increased the wettability of this polymer and improved proliferation of HGF. Therefore, PEEK implant components may be a valid choice in areas of esthetic challenges, where maximum soft tissue contact is essential.