钛表面粗糙度对成骨细胞核心结合因子α1亚基基因表达的影响

目的 通过研究种植体表面粗糙度对成骨细胞黏附、增殖、碱性磷酸酶(alkaline phosphatase,ALP)含量以及核心结合因子α1亚基(core bindingfactor alpha 1 subunit,Cbfα1)基因表达的影响,探讨种植体表面形态影响界面生物学反应的可能途径.方法 直径15 mm、厚2 mm的纯钛圆盘试件48个,均分为4组,每组12个.分别采用粒度为88～125μm(微度粗糙组)、125～150μm(中度粗糙组)、250～500μm(重度粗糙组)的金刚砂颗粒喷砂,后两组试件再用10%的盐酸、硫酸混合液处理5 min;剩余1组未处理作为对照组.测试4组试件表面粗糙度.将成骨细胞接种于4组试件表面,采用扫描电镜、吖啶橙荧光染色及考马斯亮蓝染色检测试件粗糙度对成骨细胞黏附、增殖的影响.采用酶联免疫吸附实验(enzyme linked immunosorbent assay,ELISA)测定成骨细胞ALP含量的变化.采用荧光实时定量聚合酶链反应测定成骨细胞Cbfα1基因表达的变化.结果 处理后微、中、重度粗糙组和对照组的粗糙度分别为(1.00±0.20)、(1.67±0.08)、(2.40±0.20)和(0.12±0.03)μm.3个粗糙组成骨细胞的数量及ALP含量均高于对照组(P＜0.05).与对照组相比,粗糙表面上Cbfα1的mRNA水平明显增加(P＜0.05);中度粗糙组为(0.93±0.03);微度粗糙组次之,为(0.50±0.03);重度粗糙组最低,为(0.37±0.07);对照组仅为(0.10±0.06).结论 种植体表面粗糙度的差异可造成成骨细胞骨源性基因Cbfα1表达及ALP含量不同.粗糙度在1～2μm范围内成骨细胞的生长、ALP含量及Cbfα1基因的表达较强.

Influence of surface roughness of titanium implant on core binding factor alpha 1 subunit of osteoblasts

Objective To determine whether the roughness of titanium implant can influence its osseointegration by affecting the growth, alkaline phosphatase (ALP) production and expression of core binding factor alpha 1 subunit (Cbfα1) of osteoblasts. Methods Totally 48 titanium disc specimens,15 mm in diameter and 2 mm in thickness, were included in the study and divided equally into 4 groups with 12 specimens in each group. Specimens were coarsened by sandblasting with carborundum granula and acid etching with mixing liquid of hydrochloric acid and sulphuric acid under diverse conditions. In the four groups, three were treated with different surface roughness: micro-roughness [ (1.00 ± 0. 20 ) μm ],midrange roughness [ ( 1.67 ± 0. 08 ) μm ] and severe roughness [ ( 2. 40 ± 0. 20) μm ], while the group untreated with surface roughness [ (0. 12 ± 0. 03 ) μm ] was set as control Scanning electron microscope,acridine orange fluorescence staining and coomassie brilliant blue staining were used to observe morphology and growth of osteoblasts incubating on these specimens. Enzyme linked immunosorbent assay(ELISA) and fluorescence quantitative real-time polymerase chain reaction were used to evaluate ALP production and gene expression of Cbfαl of osteobalsts among different groups. Results Growth, ALP production and CbfαlmRNA expression of osteoblasts in experimental groups were higher than those in control group( P <0. 05 ).Significant differences of these data were also found among three experimental groups ( P < 0. 05 ). Midrange roughness group showed the highest level of gene expression of Cbfαl mRNA, which was 0. 93 ± 0. 03.While that in the micro-roughness group (0. 50 ± 0. 03 ) came second, and the severe roughness group had the lowest data, which was 0. 37 ± 0. 07. Conclusions Results indicated that rough surface was more suitable for the adherence and propagation of the osteoblasts than smooth one did. Surface with roughness of 1～2 μm may be a better choice for osseointegration between osteoblasts and dental implants than others are.