Experimental study of the Ti-implant surfaces structured by the ytterbium-doped pulsed fiber laser

Relevance. Currently, there are several basic techniques for the dental implant surface structuring. Laser treatment is an extremely promising technique for the surface structuring. This technology allows creating regular implant surface without using chemicals and in just one technological step. The purpose was to present study aimed to compare and evaluate in vivo the stability and osseointegration of dental implants with 2 different surfaces structured by ytterbium-doped pulsed fiber laser operating at 1064 nm.

Materials and methods. 60 dental implants were placed in the study. 2 types of dental implant surfaces, namely holes and parallel grooves, were created by the ytterbium laser operating at 1064 nm. A polished dental implant (without laser surface structuring) was also included in the experiment for comparison. The study was carried out on 15 laboratory animals (male rabbits, weight 3.5-4 kg). The implants were placed in the tibia. 4 implants with different surface types but of the same diameter and length were placed in each rabbit.

Results. Laboratory animals were sacrificed 1.5 and 3 months after the surgery. The stability of the implants was assessed by RFA (Resonance Frequency Analysis), based on the registration of resonance electromagnetic oscillations of the implant and the surrounding bone when they are exposed to the electromagnetic field (Osstell ISQ). Also, nondecalcified bone blocks were histologically examined using a confocal laser scanning microscope (Carl Zeiss LSM 780) and histomorphometry was performed (BIC-index: Bone-to-implant contact). Bone blocks were prepared according to a special technique: they were soaked and embedded into the plastic and synthetic resin. The obtained blocks were cut into sections, 40-50 µm thick, and stained with toluidine blue.

Conclusion. Laser surface structuring of the dental titanium implants is a promising technique. 59 in 60 (98.3%) implants were osseointegrated, there were no signs of inflammation in the bone tissue. The present results allow further studying of dental implants with various surface designs, structured by ytterbium laser.

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