BackgroundZirconia is characterized by a hard, dense, and chemically inert surface which requires additional surface treatments in order to enhance osseointegration. The proposed hypothesis of the study was that combination of a nano-porous surface infiltrated with a bioactive material may enhance osseointegration of zirconia implants.MethodsCustom-made zirconia implants (3.7 mm × 8 mm) were designed, milled, and sintered according to manufacturer recommendations. All implants received selective infiltration etching (SIE) technique to produce a nano-porous surface. Surface porosities were either filled with nano-hydroxy apatite particle- or platelet-rich plasma while uncoated surface served as a control (n = 12, α = 0.05). New surface properties were characterized with mercury porosimetry, XRD analysis, SEM, and EDX analysis. Implants were inserted in femur head of rabbits, and histomorphometric analysis was conducted after healing time to evaluate bone–implant contact percentage (BIC%).ResultsSelective infiltration etching produced a nano-porous surface with interconnected surface porosities. Mercury porosimetry revealed a significant reduction in total porosity percent after application of the two coating materials. XRD patterns detected hexagonal crystal structure of HA superimposed on the tetragonal crystal phase of zirconia. Histomorphometric analysis indicated a significantly higher (F = 14.6, P < 0.001) BIC% around HA–bioactive–hybrid surface (79.8 ± 3%) and PRP-coated surface (71 ± 6 %) compared to the control (49 ± 8%).ConclusionsBioactive–hybrid–zirconia implant surface enhanced osseointegration of zirconia implants.

Objectives: The aim of this study was to evaluate the shear bond strength of three different types of bonding systems for orthodontic brackets to tooth surface. Materials and Methods: Sixty sound premolar teeth divided randomly into three groups of 20 each. In group A, the brackets were bonded using conventional etch system. In group B, brackets were bonded using self-etch primer system, while in group C, brackets were bonded using one step adhesive system. Premolar teeth were mounted with cold acrylic resin in metallic mold and brackets were shear tested to failure using universal testing machine recorded in Newton for all specimens. Results: Group C shows significantly higher value of shear bond strength in comparison to groups A and B, while there was no significant difference between group A and B. Conclusion: Orthodontic brackets bonded to enamel surface using one-step bonding system (GC ortho connect) without primer was significantly higher than brackets bonded using conventional or self-etch systems.

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