Epithelial Cell Adhesion and Proliferation on Titanium(V) Biofunctionalized with Nanoceramic Thin Film

A. Abstract Statement of Problem: Titanium abutments are widely used in implant dentistry, but exhibit poor soft tissue sealing, making the crestal bone vulnerable to microbial invasion. Purpose: To evaluate the effects of atomic layer deposition (ALD) of ZrO2-TiO2 nanoceramic thin film coating, with and without ultraviolet C (UVC) irradiation, on titanium(V) surface hydrophilicity, and adhesion and proliferation of human gingival keratinocytes. Materials and Methods: Polished titanium(V) disks were randomly divided into three groups: control (uncoated), ALD (ZrO2:TiO2 coated at 1:4), and ALD-UV (ZrO2-TiO2 coated and UVC-treated). Surface wettability was evaluated via measuring water contact angle (n=5). Telomerase-immortalized human gingival keratinocytes (TIGKs) were cultured on each treated or untreated disk. Cell viability and adhesion were assessed at 6 and 24 hours via fluorescence microscopy (n=7), and proliferation was measured on days 1, 3, and 6 via colorimetric assay (n=7). Cell morphology was qualitatively examined with scanning electron microscopy (SEM). One-way ANOVA (water contact angle), and two-way ANOVA (adhesion and proliferation) with Tukey’s HSD post hoc tests with α = .05 were used for statistical analysis Results: The coating reduced water contact angle from 75.76° to 6.68° (P<0.0001), which increased to 50.49° after 48-hour air exposure (P<0.0001); UVC irradiation partially restored hydrophilicity to 34.33° (P<0.0001), but did not affect TIGK adhesion or proliferation. TIGKs were viable on control and coated samples with or without UVC treatment. For control, ALD, and ALD-UV groups, attached cell densities at 6-hour were 207, 150, and 156 cells/mm2, respectively, which significantly increased to 1056, 858, and 1012 cells/mm2 by 24-hour. The mean absorbances of these groups were 0.16, 0.15, and 0.16 at day 1, 0.80, 0.74, and 0.74 at day 3, and 1.06, 1.22, 1.03 at day 6, indicating significant cell proliferation. No significant differences in cell adhesion or proliferation among those three groups were observed through day 3. However, ALD group showed significantly higher proliferation than control and ALD-UV (P < .05, P < 0.001) at day 6. SEM revealed that TIGKs initially displayed round to spindle-shaped morphologies aligning along nano-grooves (contact guidance) during early adhesion at 6- or 24-hour, and more uniform spreading at days 3 and 6 for all groups. Conclusions: Coating titanium(V) with ZrO₂-TiO₂ composite nanoceramic thin films enhanced long-term human gingival keratinocyte attachment and proliferation in-vitro. UVC irradiation of coating improved wettability, but not biological activity. Clinical Implications: Coating titanium abutments with nanoceramic films via ALD may improve the peri-implant soft tissue seal, potentially reducing risk of microbial ingress and recession.

Author dc:creator

• Donghyun Kim (179170)

• Health Sciences, Dentistry
• Engineering, Materials Science
• Engineering, Chemical
• Biology, Cell

Statement dc:rights

• In Copyright
• Open Access after 2028-05-01

DOI dc:identifier

https://doi.org/10.25417/uic.32994974.v1

OAI identifier oai:identifier

oai:figshare.com:article/32994974