Micro-arc Oxidation (MAO) Coupling Electrophoresis Deposition (EPD) Versus Hydroxyapatite Coating in Periimplantitis: An Experimental Study in Dog

Object: This paper aims to evaluate the influence of dental implants coated with hydroxyapatite (HA) and implants processed by micro-arc oxidation (MAO) coupling electrophoresis deposition (EPD) on experimental peri-implantitis in Beagle dogs. Methods: The thirty-six implants (diameter 3.3 mm & length 11 mm) were equally divided into three groups. Group A was processed with a plasma-sprayed layer of HA, group B was surfaced with MAO and EPD, and group C was not-treated. The morphological surface characteristics and the surfaces chemical composition were observed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). These implants were randomly placed into the alveolar bone of mandible of dogs. After three months (healing stage), cotton ligatures with P. gingivalis (strain ATCC 33277) were replaced in the submarginal position around the neck of the implants to induce peri-implantitis. Clinical measurements, including peri-implant probing pocket depth (peri-implant PD), and bleeding on the probing were recorded every 2 weeks during subsequent six weeks. After the animals were euthanized, implants and surrounding tissues were retrieved. The length of bone loss (BLL) was measured. Result: The BLL of group A (4.66 ± 0.22) was higher than that of group B (4.04 ± 0.29), but it was lower than that of group C (5.08 ± 0.28). The difference was statistically significant (P<0.05). Conclusion: Dental implants with MAO coupled with EPD could be more effective for slowing down periimplantitis progression than HA-coated implants and nottreated implants.