Surface Topography of Titanium Affects Their Osteogenic Potential through DNA Methylation

Abstract

It is widely accepted that sandblasted/large-grit/acid-etched (SLA) surfaces of titanium (Ti) have a higher osteogenic potential than machined ones. However, most studies focused on differential gene expression without elucidating the underlying mechanism for this difference. The aim of this study was to evaluate how the surface roughness of dental Ti implants affects their osteogenic potential. Mouse preosteoblast MC3T3-E1 cells were seeded on machined and SLA Ti discs. The cellular activities of the discs were analyzed using confocal laser scanning microscopy, proliferation assays, and real-time polymerase chain reaction (PCR). DNA methylation was evaluated using a methylation-specific PCR. The cell morphology was slightly different between the two types of surfaces. While cellular proliferation was slightly greater on the machined surfaces, the osteogenic response of the SLA surfaces was superior, and they showed increased alkaline phosphatase (Alp) activity and higher bone marker gene expression levels (Type I collagen, Alp, and osteocalcin). The degree of DNA methylation on the Alp gene was lower on the SLA surfaces than on the machined surfaces. DNA methyltransferase inhibitor stimulated the Alp gene expression on the machined surfaces, similar to the SLA surfaces. The superior osteogenic potential of the SLA surfaces can be attributed to a different epigenetic landscape, specifically, the DNA methylation of Alp genes. This finding offers novel insights into epigenetics to supplement genetics and raises the possibility of using epidrugs as potential therapeutic targets to enhance osteogenesis on implant surfaces.

Corrosion Resistance and Surface Bioactivity of Ti6Al4V Alloy after Finish Turning under Ecological Cutting Conditions

“…HA is like a bioceramic that has very good biological properties facilitating bone repair and reconstruction [40]. The surface roughness of titanium alloys suitable for the growth of osteoblasts is 0.2-0.7 µm, and, in the literature, many reports can be found on the protective and bioactive layers on titanium alloys and their corrosion resistance [41][42][43][44].…”

Influence of epigenetics on periodontitis and peri‐implantitis pathogenesis

“…87 Treatment with 5-aza-2′-deoxycytidine of osteoblasts grown on titanium discs of two different surface characteristics decreased DNA methylation on both surfaces and induced gene expression of alkaline phosphatase. 88 Decitabine (5-aza-2′-deoxycytidine) was found to reduce bone loss in a mouse periodontitis model by inhibiting osteoclastogenesis. 89 Another challenge in periodontal tissue regeneration is reducing inflammation.…”

“…29 In addition, the methylation level of the alkaline phosphatase gene was lower in osteoblast cells grown on smooth titanium surfaces than in cells grown on modified titanium surfaces. 88 Interestingly, surface decontamination using mechanical methods was found to further influence epigenetic markers. 111 In a previous study, preosteoblastic cells were grown on titanium discs with various surfaces: machined, dual acid-etched, and acid-etched nanohydroxyapatite-blasted.…”

Role of chitosan in titanium coatings. trends and new generations of coatings

“…In this regard, some studies on implant surfaces and osteoblast differentiation have focused on differences in the osteogenic potential of surfaces as a function of gene expression levels, and some have reported that implant surface topography can alter cellular activity (Zheng et al, 2020;Ichioka et al, 2021). A study by Cho et al concluded that the surface topography of Ti implants affects their osteogenic potential through epigenetic changes, raising the possibility of using epidrugs to enhance osteogenesis on implant surfaces (Cho et al, 2021).…”