title: Genetic responses to nanostructured calcium-phosphate-coated implants.
abstract: Nanostructured calcium phosphate (CaP) has been histologically and biomechanically proven to enhance osseointegration of implants; however, conventional techniques were not sufficiently sensitive to capture its biological effects fully. Here, we compared the conventional removal torque (RTQ) evaluation and gene expression in tissues around nanostructured CaP-coated implants, using real-time RT-PCR, with those of uncoated implants, in a rabbit model. At 2 wks, RTQ values were significantly higher, alkaline phosphatase (ALP) expression was significantly higher, and runt-related transcription factor 2 and tumor necrosis factor-α expressions were significantly lower in the coated than in the uncoated implants. This indicates that inflammatory responses were suppressed and osteoprogenitor activity increased around the CaP-coated surface. At 4 wks, although RTQ values did not significantly differ between the 2 groups, ALP and osteocalcin (OCN) were significantly up-regulated in the coated group, indicating progressive mineralization of the bone around the implant. Moreover, an osteoclast marker, adenosine triphosphatase, which indicates acidification of the resorption lacunae, was significantly higher for the coated implants, suggesting gradual resorption of the CaP coating. This study reveals detailed genetic responses to nanostructured CaP-coated implants and provides evidence that the effect of nanotopography is significant during the osseointegration cascade.
authors.affiliation: Surface Biology Group, Department of Prosthodontics, Faculty of Odontology, Malmö University, 205 06 Malmö, Sweden. ryo.jimbo@mah.se
authors.forename: R
authors.initials: R
authors.lastname: Jimbo
authors.forename: Y
authors.initials: Y
authors.lastname: Xue
authors.forename: M
authors.initials: M
authors.lastname: Hayashi
authors.forename: H O
authors.initials: HO
authors.lastname: Schwartz-Filho
authors.forename: M
authors.initials: M
authors.lastname: Andersson
authors.forename: K
authors.initials: K
authors.lastname: Mustafa
authors.forename: A
authors.initials: A
authors.lastname: Wennerberg
mesh_terms: D000135:Acid Phosphatase / Q000096:biosynthesis; D000818:Animals; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D050659:Core Binding Factor Alpha 1 Subunit / Q000096:biosynthesis; D003799:Dental Stress Analysis; D020878:Device Removal; D015870:Gene Expression; D020007:Implants, Experimental; D007527:Isoenzymes / Q000096:biosynthesis; D053758:Nanoparticles; D010006:Osteoblasts / Q000378:metabolism*; D015675:Osteocalcin / Q000096:biosynthesis; D011817:Rabbits; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction; D000071681:Tartrate-Resistant Acid Phosphatase; D019415:Torque; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D050659:Core Binding Factor Alpha 1 Subunit; D007527:Isoenzymes; D014409:Tumor Necrosis Factor-alpha; D015675:Osteocalcin; C020243:calcium phosphate; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase