Evaluation of dental implant with hydroxyapatite coating by laser-induced hydrothermal synthesis: in vitro and in vivo experimental study

Abstract

Various attempts to increase the survival rate of dental implant have been introduced. Among the, there have been many studies for modification of implant surfaces. This study aimed to evaluate the results of in vitro and in vivo experiments on implants using a nano/micro-assembled hydroxyapatite (HA) structure with laser-induced single-step coating (LISSC) technique. In this study, machined surface implants (MA), sandblasted, large-grit, acid-etched surface implants (SLA), resorbable blasting media surface implants (RBM), and hydroxyapatite surface implants (HA) were used. Surface morphology, surface hydrophilicity and cell attachment analysis were conducted (in vitro). Twelve rabbits and two beagles were used in this in vivo study. Immediately after placement, the implant stability quotient (ISQ) was measured using the Osstell mentor device. After the animals were sacrificed (rabbit: 3 and 6 weeks; beagle: 12 weeks), histological, bone-implant contact ratio (BIC%), and bone volume ratio (BV%) analyses were performed. The ISQ value increased from post-OP to 6 or 12 weeks for all animal implant types. The results of in vitro experiment were shown as follows: “HA > RBM > SLA > MA (roughness value)” and “RBM > HA > MA > SLA (surface wettability)”. There were no statistically significant differences in initial cell adhesion and viability among four groups (cell attachment). According to the in vivo results, BV were measured in the order “SLA > RBM > HA > MA (3-week)” and “SLA > HA > RBM > MA (6-week)”. For BIC, the results were as follows: RBM > HA > MA > SLA (3 weeks) and HA > RBM > SLA > MA (6 weeks). HA showed the greatest increases in BV and BIC from 3 to 6 weeks (HA > SLA > RBM > MA). In the beagle experiment, the ISQ value at 12 weeks was higher than that post-OP for both HA and SLA. HA was higher than SLA in the BV group. HA implants act at a similar or equivalent level to other implants (MA, SLA, and RBM).