Journal of Oral Implantology October 2013 - (Page 591)

RESEARCH Modified Titanium Surfaces Alter Osteogenic Differentiation: A Comparative Microarray-Based Analysis of Human Mesenchymal Cell Response to Commercial Titanium Surfaces Anastasios Mamalis, DDS, PhD1* Spyridon Silvestros The differential effects of dual-acid etched (Osseotite), hydroxyapatite coated (HA) and sand-blasted/acidetched (SLA) titanium surfaces on human bone marrow-derived mesenchymal cells (hMSCs) were investigated. Proliferation was significantly promoted on the SLA surfaces. 16 genes were significantly upregulated when hMSCs were cultured on the Osseotite and the HA surfaces and 15 genes on the SLA surfaces. Upregulated genes control cell differentiation, signal transduction, cell cycle regulation, angiogenesis, cell adhesion, and extracellular matrix and bone formation. Key Words: human mesenchymal cells, dental implants, gene expression INTRODUCTION C ommercial pure titanium (Ti) and its alloys are currently used as implant materials because they exhibit excellent mechanical properties, chemical stability, and biocompatibility.1 The biocompatibility of Ti is closely related to its surface properties: roughness, topography, and chemistry.2 Implant surface modification by altering topographical and chemical surface properties may enhance the process of osseointegration.3 Both in vivo and in vitro research efforts have extensively studied the effect of surface roughness to the outcome of osseointegration. In vivo, rough surfaces have demonstrated to promote bone-toimplant contact as compared to smooth surfaces.4,5 In addition, it has been demonstrated that the removal torque of rough implants is significantly 1 University of Texas Health Science Center at San Antonio, San Antonio, Texas. * Corresponding author, e-mail: mamalis@uthscsa.edu DOI: 10.1563/AAID-JOI-D-10-00209 increased corresponding to a higher anchorage level than that of smooth implants.6,7 In vitro research on the effects of surface roughness to osseointegration has provided controversial results. Human cells with a prominent fibroblastic phenotype, such as gingival fibroblasts or human periodontal ligament cells have demonstrated a greater attachment rate to smooth rather than rough surfaces.8,9 On the other hand, human cells with a clear osteoblastic phenotype attach preferentially to rough surfaces.10–12 Surface roughness regulates in vitro cellular activities; proliferation, differentiation, initial attachment, and protein production are upregulated when cells are grown on rough surfaces. Also, it has been evident that as surface roughness increases, cell differentiation is driven towards a clear osteoblastic phenotype where cells secrete alkaline phosphatase, osteocalcin, osteoprotegerin, and transforming growth factor-beta (TGF-b).13–15 Increased osteogenic differentiation in response to rough surfaces was correlated to elevated alkaline Journal of Oral Implantology 591

Table of Contents for the Digital Edition of Journal of Oral Implantology October 2013

Food and Drug Administration: Reclassification of Blade Form Dental Implants
Optimizing Platelet-Rich Plasma Gel Formation by Varying Time and Gravitational Forces During Centrifugation
Effect of Surface Roughness and Low-Level Laser Therapy on Removal Torque of Implants Placed in Rat Femurs
Impression Techniques for Multiple Implants: A Photoelastic Analysis. Part I: Comparison of Three Direct Methods
Impression Techniques for Multiple Implants: A Photoelastic Analysis. Part II: Comparison of Four Acrylic Resins
A Pig Model for the Histomorphometric Evaluation of Hard Tissue Around Dental Implants
In Situ Tooth Replica Custom Implant: A 3-Dimensional Finite Element Stress and Strain Analysis
Influence of Different Soft Liners on Stress Distribution in Peri-Implant Bone Tissue During Healing Period. A 3D Finite Element Analysis
Influence of Surface Nano-Roughness on Osseointegration of Zirconia Implants in Rabbit Femur Heads Using Selective Infiltration Etching Technique
Modified Titanium Surfaces Alter Osteogenic Differentiation: A Comparative Microarray- Based Analysis of Human Mesenchymal Cell Response to Commercial Titanium Surfaces
Hemorrhage Secondary to Interforaminal Implant Surgery: Anatomical Considerations and Report of a Case
Rehabilitation of a Patient With Mandibular Resection Using Osteointegrated Implants: A Case Report
Two-Stage Bone Expansion Technique Using Spear-Shaped Implants Associated With Overlapped Flap: A Case Report
Implant Esthetic Restoration in Ridge Deficiencies in Cases of Trauma: A Case Report
Rehabilitation of the Atrophic Maxilla With Tilted Implants: Review of the Literature

Journal of Oral Implantology October 2013