Research Article Surface Characteristics and Bioactivity of a Novel Natural HA/Zircon Nanocomposite Coated on Dental Implants Ebrahim Karamian, 1 Amirsalar Khandan, 2 Mahmood Reza Kalantar Motamedi, 3 and Hesam Mirmohammadi 4,5 1 Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Isfahan, Iran 2 Young Researchers and Elite Club, Khomeinishahr Branch, Islamic Azad University, Isfahan, Iran 3 Dental Students Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran 4 Dental Materials Research Center, Department of Restorative Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran 5 Department of Cariology Endodontology Pedodontology, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam 1081 JD, he Netherlands Correspondence should be addressed to Hesam Mirmohammadi; hmirmoha@acta.nl Received 5 February 2014; Accepted 1 April 2014; Published 16 April 2014 Academic Editor: David M. Dohan Ehrenfest Copyright © 2014 Ebrahim Karamian et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. he surface characteristics of implant which inluence the speed and strength of osseointegration include surface chemistry, crystal structure and crystallinity, roughness, strain hardening, and presence of impurities. he aim of this study was to evaluate the bioactivity and roughness of a novel natural hydroxyapatite/zircon (NHA/zircon) nanobiocomposite, coated on 316L stainless steel (SS) soaked in simulated body luid (SBF). NHA/zircon nanobiocomposite was fabricated with 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% of zircon in NHA using ball mill for 20 minutes. he composite mixture was coated on 316L SS using plasma spray method. he results are estimated using the scanning electron microscopy (SEM) observation to evaluate surface morphology, X-ray difraction (XRD) to analyze phase composition, and transmission electron microscopy (TEM) technique to evaluate the shape and size of prepared NHA. Surfaces roughness tester was performed to characterize the coated nanocomposite samples. he maximum average   (14.54 m) was found in the NHA 10wt.% of zircon coating. In addition, crystallinity (  ) was measured by XRD data, which indicated the minimum value (  = 41.1%) for the sample containing 10 wt.% of zircon. Maximum bioactivity occurred in the sample containing 10 wt.% of zircon, which was due to two reasons: irst, the maximum roughness and, second, the minimum crystallinity of nanobiocomposite coating. 1. Introduction Dental implants are well-accepted and predictable treatment modalities for rehabilitation of patients with partial and complete edentulism. Dental implantation has become an established treatment method since its appearance for over 40 years. he future would probably see bioactive surfaces and additives that stimulate the bone growth. According to Albrektsson et al. several factors can afect the osseointegra- tion, including implant material, implant design, implant sur- face characteristics, status of the bone, surgical technique, and implant loading conditions [1]. Nowadays, there is an efort to speed up the osseointegration by improving the implant-to- bone interface chemically (by incorporating inorganic phases on or into the titanium oxide layer) or physically (by increas- ing the level of roughness) [2]. here are some advantages regarding surface modiied implants, including (a) providing a better stability between bone and implant during healing process, established by a greater contact area, (b) providing a surface coniguration that may retain the blood clot, and (c) stimulating the bone formation and healing process [3]. here are several methods to improve the quality of implant surface; one of them is adding bioactive materials to the surface of the dental implant to induce osteoconductivity. Hydroxyapatite (HA), [Ca 10 (PO 4 ) 6 (OH) 2 ], is a calcium phosphate bioceramic material, with osteoconductivity and excellent biocompatibility. However, apatite layers coating Hindawi Publishing Corporation BioMed Research International Volume 2014, Article ID 410627, 10 pages http://dx.doi.org/10.1155/2014/410627