Effects of ultraviolet treatment and alendronate immersion on osteoblast-like cells and human gingival fibroblasts cultured on titanium surfaces

In this study, we evaluated the effects of ultraviolet (UV) treatment and alendronate (ALN) immersion on the proliferation and differentiation of MG-63 osteoblast-like cells and human gingival fibroblasts (HGFs) cultured on titanium surfaces. MG-63 cells were used for sandblasted, large grit, and acid-etched (SLA) titanium surfaces, and HGFs were used for machined (MA) titanium surfaces. SLA and MA specimens were subdivided into four groups (n = 12) according to the combination of surface treatments (UV treatment and/or ALN immersion) applied. After culturing MG-63 cells and HGFs on titanium discs, cellular morphology, proliferation, and differentiation were evaluated. The results revealed that UV treatment of titanium surfaces did not alter the proliferation of MG-63 cells; however, HGF differentiation and adhesion were increased in response to UV treatment. In contrast, ALN immersion of titanium discs reduced MG-63 cell proliferation and changed HGFs into a more atrophic form. Simultaneous application of UV treatment and ALN immersion induced greater differentiation of MG-63 cells. Within the limitations of this cellular level study, simultaneous application of UV treatment and ALN immersion of titanium surfaces was shown to improve the osseointegration of titanium implants; in addition, UV treatment may be used to enhance mucosal sealing of titanium abutments.ope

자외선 조사 및 알렌드로네이트 침지를 이용한 표면 처리가 티타늄 기판 상에서 유사골모세포 및 인간치은섬유모세포의 세포 반응에 미치는 영향

Titanium is widely used as a dental implant material due to its biocompatibility and excellent physical properties. However, when exposed to the external environment over time, the titanium surface becomes contaminated, leading to decreased bio-responses related to osseointegration of the implant surface and the mucosal seal around the abutments. As a part of approach to overcome the above phenomenon, this study aimed to investigate the effects of ultraviolet (UV) irradiation and alendronate (ALN) immersion on the response of osteoblast-like cells and gingival fibroblasts cultured on the titanium surface, as a part of approach to overcome the above phenomenon. Titanium discs were fabricated with a diameter of 10 mm and a thickness of 2 mm, using grade 4 titanium. Titanium substrates were classified as sandblasted with large grit and acid-etched (SLA) surface or machined (MA) surface, and further sub-divided into the following four categories to produce a total of eight groups (n = 12 per group): no treatment, only UV irradiation, only ALN immersion, and UV irradiation with ALN immersion (dual application). MG-63 osteoblast-like cells and gingival fibroblasts were cultured on the SLA surface groups and the MA surface groups, respectively. The morphology and attachment of cells and the extent of proliferation, differentiation, and attachment were examined using a scanning electron microscope, WST-8 (water-soluble tetrazolium-8) analysis, alkaline phosphatase (ALP) activity assay, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Statistical analyses were performed using a one-way analysis of variance for cell proliferation, differentiation, and attachment-related gene expression. Proliferation of MG-63 cells significantly decreased in ALN-treated groups compared to the non-ALN-treated groups (P < 0.05). However, in dual application group, there was a significant increase in ALP activity of MG-63 osteoblast-like cells, compared to the control group (P < 0.05). Proliferation of gingival fibroblasts was decreased in the dual application group compared to UV or ALN-only groups (P < 0.05). The mRNA (messenger ribonucleic acid) expression related to the attachment of gingival fibroblasts significantly increased in the UV-only group, compared to the other groups (P < 0.05). Accordingly, dual application of UV irradiation and ALN immersion on the SLA surface augmented the differentiation of MG-63 osteoblast-like cells, and UV irradiation on the MA surface promoted the expression of factors related to the attachment of gingival fibroblasts. Further studies are required to verify the clinical usefulness of these findings.open박

Digital workflow to provide an immediate interim restoration after single-implant placement by using a surgical guide and a matrix-positioning device

This article describes a workflow based on a top-down approach to provide a fixed-type immediate interim restoration after placing a single implant using a digitally driven surgical guide and a matrix-positioning device. A characteristic of the technique is that both the surgical guide and the matrix-positioning device are fabricated from a single diagnostic virtual trial restoration designed on computer-aided design (CAD) software. This workflow may shorten the time required for chairside placement of an interim restoration and enhance esthetics when rehabilitating anterior teeth.restrictio