Effect of Surface Roughness of Titanium Dental Implant Placed under Periosteum on Gene Expression of Bone Morphogenic Markers in Rat

Abstract

Various bone matrix proteins are produced during the process of osteogenesis. Many previous studies suggested that the topography of an implant surface might affect the expression of osteoblast-mediated cytokines. However, these earlier studies were performed using in vitro cell culture. This study investigated the influence of the surface topography of a titanium implant placed under the periosteum on the gene expression of bone morphogenic markers in rat. Six custom-made implants with a rough upper surface and 6 custom-made implants with a smooth machined upper surface were placed subcrestally with the upper surface facing up in the femurs of 6 adult male rats. Five rats were sacrificed 7 days after the implant placement, and the periosteum above the embedded implant was obtained and analyzed by quantitative real-time RT-PCR for the target genes: alkaline phosphatase (ALP), bone sialoprotein (BSP) and osteocalcin (OCN). The other rat was sacrificed at day 7, and both implants and the surrounding tissue were embedded in paraffin. For light microscopic observations, paraffin sections were stained with toluidine blue. Gene expression of ALP , BSP and OCN at the rough surface implant was significantly higher than that at the smooth machined surface implant. At day 7, both types of implant were covered with soft tissue, but a lower number of cells stained with toluidine blue was observed on the machined surface compared with on the rough surface. It is considered that rough surfaces may stimulate osteoblasts, and that ALP activity is increased indirectly. Furthermore, the two other markers were also increased by the rough surface in vivo, and different distributions of cellular and extracellular components on the upper surface of the implants were observed at day 7. These results suggest that a rough surface implant under the periosteum promotes higher gene expression of ALP, BSP and OCN in rat.

The effects of implant topography on osseointegration under estrogen deficiency induced osteoporotic conditions: Histomorphometric, transcriptional and ultrastructural analysis

“…Micro-rough surface implants have been shown to increase osteoblastic cell attachment and differentiation [54][55][56][57][58] and result in higher osteogenic gene expression (ALP, bone sialoprotein, OC) compared with machined implants [59,60]. Our study also found a significant increase in the expression of osteoblast markers (ALP and OC) in the SHAM micro-rough implant group, which is consistent with previously reported data [59] and provides further evidence that micro-rough surfaces have an enhanced osteogenic capacity compared to machined surfaces. However, the micro-rough implants in the OVX group did not show an increase in osteogenic gene expression despite an increase in the number and organization of osteoblasts shown histologically (compared to the OVX machined group).…”

Low Pressure Radio-Frequency Oxygen Plasma Induced Oxidation of Titanium – Surface Characteristics and Biological Effects

“…The surface properties, including surface roughness, free energy and tomography, play a key factor for cellular adhesion and proliferation [ 6 , 35 - 39 ]. In this study, surface modification by OP provided better condition of cell spreading and growth, especially after 5 min OPT.…”

Dynamics of biochemical markers of the connective tissue metabolism in the blood of rats after insertion of steel implants with diamond-like carbon coating into the femur

“…According toT. Haraet al research results 6 , rough surface implants under the periosteum contribute to the expression of alkaline phosphatase, bone sialoprotein and osteocalcin. The influence of chitosan-collagen composites that could induce invivo-formation of new bone tissue around the surface of the titanium implant was also studied.…”