Cementing Line Configuration of Bioactive Engineered Zirconia Implants (In Vivo Histological Study)

Abstract

Background: Osseointegration of dental implant is a challenging issue for those who need to restore a missing tooth, a matter that necessitates wide range of research on different implant manufacturing, modification and bioactive coating materials.Aim of the study: Investigation of cementing line configuration around osseointegrated engineered nano-porous zirconia implants coated with bioactive autologous HA, platelet rich plasma (PRP) and bovine HA (Bio-oss) coatings in rabbit model.Materials and methods: Zirconia implants (cylinders 3.7 mm x 8 mm) were milled and sintered according to manufacturer recommendations. Then all specimens were treated with selective infiltration etching (SIE) to produce a nano-porous surface. Implants were surgically placed bilaterally in the femur distal heads of 20 male line V Spain white rabbits. Implants were divided equally into 4 groups (n=10): group (A) control (non-coated), group (B) autologous HA coated, group (C) PRP coated and group (D) Bio-Oss coated implants. Specimens were characterized with x-ray diffraction (XRD) analysis and mercury porosimetery. Histological examination was performed after six weeks of peri-implant healing period.Results: XRD patterns revealed the detection of hexagonal HA and (Y-TZP) tetragonal crystal phases for the HA coated surfaces. Mercury porosimetery revealed a significant reduction in total porosity percent after application of bioactive coating materials. The histological picture of osseiointegration and cementing line continuity in association with both of autologous HA and PRP were outstanding and satisfactory followed by that of Bio-Oss and all coated implants showed a noticeable difference from that of the control specimens that were surrounded by unsupported cementing line adjacent to newly formed bone with low density.Conclusions: Engineering of zirconia implant surface with bioactive coatings either HA or PRP to enhance its biological activity could be considered as reliable method to provide satisfactory osseiointegration.