Osteoblastic and osteoclastic differentiation on SLA and hydrophilic modified SLA titanium surfaces

Purpose We evaluated the activities of both osteoblastic and osteoclastic differentiation on sandblasted/acid etched (SLA), hydrophilic SLA surfaces (modSLA) and pretreatment titanium (PT). Material and methods The osteoblastic differentiation was evaluated by alkaline phosphatase analysis and Alizarin Red S staining, and the expression of bone‐related proteins, alkaline phosphatase (ALP), runt‐related transcription factor 2 (Runx2), osteopontin (OPN), and osteocalcin (OCN), was investigated by reverse transcriptase–polymerase chain reaction (RT‐PCR). Primary mice monocytes were expanded and differentiated in the presence of macrophage‐colony stimulating factor (M‐CSF), and osteoclastic differentiation was evaluated by actin ring formation assay and tartrate‐resistant acid phosphatase (TRAP) activity assay. Real‐time PCR tests were performed to investigate the expression of gene mRNA expression levels in osteoclast cells. Result Differentiation of osteoblasts in the Alizarin Red S test staining and ALP assay was significantly increased in the modSLA surface. The preceding results were supported by the result of RT‐PCR for the expression of Runx2, OPN, and OCN. As for osteoclastic activity, differentiated osteoclasts rarely existed on the SLA and modSLA surface with actin ring. The results of real‐time PCR and TRAP activity supported the preceding results. Conclusion It may be concluded that the modSLA surface promotes osteogenic effect and prevents osteoclastic differentiation. Promotion of osteoblastic proliferation after a short‐term cell culture might be responsible for stimulated bone regeneration implying that early loading may be possible. Also, the anti‐osteoclastic effect of the modSLA surface may contribute to maintenance of the marginal bone level of dental implants, implying long‐term stability would be provided by this surface technology. The modSLA surface may not only make early loading possible but possibly reduce marginal bone loss during the maintenance phase.