ABSTRACT: Tissue response following implantation determines the success of the healing process. This response is not only dependent on the chemical properties of the implant surface but also by the surface topography or its roughness. Although in vitro and in vivo studies show improved results with rough- and fluoride-modified implants, the mechanisms behind these findings are still unknown. Here, we have used a two step procedure to identify novel genes related to the early cell response of primary human osteoblasts to roughness and fluoride-modified titanium implants. 217 genes were identified by microarray analysis as response genes to roughness and 198 genes as response genes to fluoride. 11 of these identified genes have been related to bone and mineralization and were further investigated by real-time RT-PCR. After one day of culture, TLR3, ANKH, DCN, OC and RUNX2 were classified as responsive genes to roughness; DLX2 and TUFT1 as responsive genes to fluoride treatment. COLL-I, PTHLH, HES1, FST, ENPP1 and THRA as responsive genes to both, roughness and fluoride treatment. In conclusion, our strategy was useful for identifying novel genes that might be involved in the early response of osteoblasts to roughness and fluoride treatment of titanium implants. Tissue response following implantation determines the success of the healing process. This response is not only dependent on the chemical properties of the implant surface but also by the surface topography or its roughness. Although in vitro and in vivo studies show improved results with rough- and fluoride-modified implants, the mechanisms behind these findings are still unknown. Here, we have used a two step procedure to identify novel genes related to the early cell response of primary human osteoblasts to roughness and fluoride-modified titanium implants. 217 genes were identified by microarray analysis as response genes to roughness and 198 genes as response genes to fluoride. 11 of these identified genes have been related to bone and mineralization and were further investigated by real-time RT-PCR. After one day of culture, TLR3, ANKH, DCN, OC and RUNX2 were classified as responsive genes to roughness; DLX2 and TUFT1 as responsive genes to fluoride treatment. COLL-I, PTHLH, HES1, FST, ENPP1 and THRA as responsive genes to both, roughness and fluoride treatment. In conclusion, our strategy was useful for identifying novel genes that might be involved in the early response of osteoblasts to roughness and fluoride treatment of titanium implants. Human osteoblasts were cultured for 24 hours on titanium disks modified either with polished surfaces (P), grit-blasted surfaces (GB), or grit-blasted High Fluor treated surfaces (GB-HF). After 24 hours of culture RNA was isolated. 3 arrays were hybridized, one with the isolated RNA from cells cultured on titanium polished surfaces (P), one with the isolated RNA from cells cultured on titanium grit-blasted surfaces (GB) and one with the isolated RNA from cells cultured on titanium grit-blasted HF treated surfaces (GB-HF).
