Bone Healing around Titanium Dental Implants with 3 Different Surfaces: an Experimental Study in Rats

Objective: Titanium nitride (TiN) has been used in many fields as a coating of surgical instruments, with the purpose of obtaining materials more resistant to wear and corrosion and reducing in this way also the phenomena of adhesion. Aim of this study was an evaluation of the biocompatibility of TiN coated dental implants. Methods: The protocol was approved by the Ethical Committee of our University. A total of 45 rats was used in this study. A total of 180 2 mm x 2 mm implants (P.H.I, San Vittore Olona, Milano - Italy) were used. The implants were divided into 3 groups: Group 1 (60 Implants): 30 machined (M) and 30 machined coated with titanium nitride (M-TiN); Group 2 (60 Implants): 30 sandblasted (SB) and, 30 sandblasted coated with titanium nitride (SB-TiN); Group 3 (60 Implants): 30 titanium plasma spray (TPS), 30 titanium plasma spray coated with titanium nitride (TPS-TiN). Four implants were placed in each rat, two implants coated with TiN on the right tibia and two uncoated implants on the left. The animals were killed after 5, 10, 20, 30 and 60 days. Other 18 implants were used for surface roughness analysis. Results: The present study showed that the healing around the titanium nitride coated implants was similar to that observed around the uncoated surfaces. At 5-10-20-30 and 60 days, statistical analysis of the differences between the two surfaces (control and test) was not significant (p>0.05). An higher percentage of bone was found around the SB and TPS implants at the 20-30-60 days time periods, and these differences were statistically significant (p<0.05). Conclusion: TiN coating demonstrated a good biocompatibility and did not have untoward effects on the peri-implant bone formation.