Effects of storage medium and UV photofunctionalization on timerelated changes of titanium surface characteristics and biocompatibility Jian-Wei Shen,1 Yun Chen,1 Guo-Li Yang,1 Xiao-Xiang Wang,2 Fu-Ming He,1 Hui-Ming Wang3,4 1
Department of Oral Implantology, The Affiliated Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China 2 Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310006, China 3 Oral Medical Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China 4 Department of Oral and Maxillofacial Surgery, The Affiliated Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, 310006, China Received 26 September 2014; revised 28 February 2015; accepted 7 April 2015 Published online 13 May 2015 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/jbm.b.33437 Abstract: Storage in aqueous solution and ultraviolet (UV) photofunctionalization are two applicable methods to overcome the biological aging and increase the bioactivity of titanium. As information regarding the combined effects of storage medium and UV photofunctionalization has never been found in published literatures, this study focused on whether appropriate storage methods and UV photofunctionalization have synergistic effects on the biological properties of aged titanium surfaces. Titanium plates and discs were sandblasted and acid etched and then further prepared in five different modes as using different storage mediums (air or dH2O) for 4 weeks and then with or without UV treatment. The surface characteristics were evaluated with scanning electron microscopy, contact angle measurements, and X-ray photoelectron spectroscopy. MC3T3-E1 cells were cultured on the surfaces, and cellular morphology, proliferation, alkaline phosphatase activity, and osteocalcin release were evaluated.
The results showed that nanostructures were observed on water-stored titanium surfaces with a size of about 15 3 20 nm2. UV treatment was effective to remove the hydrocarbon contamination on titanium surfaces stored in either air or water. UV photofunctionalization further enhanced the already increased bioactivity of modSLA on initial cell attachment, proliferation, alkaline phosphatase activity, and osteocalcin release. Overall, UV photofunctionalization was effective in further enhancing the already increased bioactivity by using dH2O as storage medium, and the effect of UV treatment was much more overwhelming than that of the C 2015 Wiley Periodicals, Inc. J Biomed Mater storage medium. V Res Part B: Appl Biomater, 104B: 932–940, 2016.
Key Words: dental/endosteal implant, biological aging, nanostructures, hydrocarbons, UV photofunctionalization
How to cite this article: Shen J-W, Chen Y, Yang G-L, Wang X-X, He F-M, Wang H-M. 2016. Effects of storage medium and UV photofunctionalization on time-related changes of titanium surface characteristics and biocompatibility. J Biomed Mater Res Part B 2016:104B:932–940.
INTRODUCTION
Titanium implants have been widely used as anchors in dental and orthopedic reconstructive surgeries because of their excellent physicochemical properties and biocompatibility. Rapid and firm establishment of bone–titanium integration mainly depends on the characteristics of titanium surface.1–3 However, a series of recent studies3–6 reported that titanium surfaces undergo a progressive change in their biologic characteristics after processing, resulting in a significant decrease in osseointegration capability. On in vitro bioactivity, the 4-week-old titanium surfaces showed only 20%–50% of the levels of attachment, settlement, and proliferation of osteogenic cells versus new surfaces.3 In an animal model, the strength of implant fixation and the
percentage of bone coverage around implants for 4-weekold surfaces were reduced to
Department of Oral Implantology, The Affiliated Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China 2 Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310006, China 3 Oral Medical Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China 4 Department of Oral and Maxillofacial Surgery, The Affiliated Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, 310006, China Received 26 September 2014; revised 28 February 2015; accepted 7 April 2015 Published online 13 May 2015 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/jbm.b.33437 Abstract: Storage in aqueous solution and ultraviolet (UV) photofunctionalization are two applicable methods to overcome the biological aging and increase the bioactivity of titanium. As information regarding the combined effects of storage medium and UV photofunctionalization has never been found in published literatures, this study focused on whether appropriate storage methods and UV photofunctionalization have synergistic effects on the biological properties of aged titanium surfaces. Titanium plates and discs were sandblasted and acid etched and then further prepared in five different modes as using different storage mediums (air or dH2O) for 4 weeks and then with or without UV treatment. The surface characteristics were evaluated with scanning electron microscopy, contact angle measurements, and X-ray photoelectron spectroscopy. MC3T3-E1 cells were cultured on the surfaces, and cellular morphology, proliferation, alkaline phosphatase activity, and osteocalcin release were evaluated.
The results showed that nanostructures were observed on water-stored titanium surfaces with a size of about 15 3 20 nm2. UV treatment was effective to remove the hydrocarbon contamination on titanium surfaces stored in either air or water. UV photofunctionalization further enhanced the already increased bioactivity of modSLA on initial cell attachment, proliferation, alkaline phosphatase activity, and osteocalcin release. Overall, UV photofunctionalization was effective in further enhancing the already increased bioactivity by using dH2O as storage medium, and the effect of UV treatment was much more overwhelming than that of the C 2015 Wiley Periodicals, Inc. J Biomed Mater storage medium. V Res Part B: Appl Biomater, 104B: 932–940, 2016.
Key Words: dental/endosteal implant, biological aging, nanostructures, hydrocarbons, UV photofunctionalization
How to cite this article: Shen J-W, Chen Y, Yang G-L, Wang X-X, He F-M, Wang H-M. 2016. Effects of storage medium and UV photofunctionalization on time-related changes of titanium surface characteristics and biocompatibility. J Biomed Mater Res Part B 2016:104B:932–940.
INTRODUCTION
Titanium implants have been widely used as anchors in dental and orthopedic reconstructive surgeries because of their excellent physicochemical properties and biocompatibility. Rapid and firm establishment of bone–titanium integration mainly depends on the characteristics of titanium surface.1–3 However, a series of recent studies3–6 reported that titanium surfaces undergo a progressive change in their biologic characteristics after processing, resulting in a significant decrease in osseointegration capability. On in vitro bioactivity, the 4-week-old titanium surfaces showed only 20%–50% of the levels of attachment, settlement, and proliferation of osteogenic cells versus new surfaces.3 In an animal model, the strength of implant fixation and the
percentage of bone coverage around implants for 4-weekold surfaces were reduced to
