In the present investigation, four titanium (Ti) surfaces of dental implants were compared through in vitro systems. The surface roughness of Ti was measured by TR240 mobile surface roughmeter. The Ti implants were seeded with human periodontal ligament cells (hPLDCs) and maintained for a period of 0-7 days. The adhesion, proliferation, and differentiation of hPLDCs were observed by using Cell morphology, cell counting and Osteocalcin (OC) immunofluorescent staining. Results suggest that surface roughness of titanium favors hPDLCs behavior and improves cell adhesion, proliferation, and differentiation.