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Bone regeneration is a coordinated process involving connections between blood vessels and osteocytes. Angiogenesis and osteogenesis are tightly connected throughout the progression of bone regeneration. This study aimed to explore the underlying mechanism of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)-regulated angiogenesis during bone regeneration. Gene and protein expression was detected by quantitative real-time PCR and western blot assay. Vascular endothelial growth factor (VEGFA) secretion was assessed by enzyme-linked immunosorbent assay. To evaluate the effect of osteogenic differentiation, alkaline phosphatase (ALP) and alizarin red staining assays were performed. Proliferation was detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Migration and angiogenesis were measured using Transwell and tube formation assays. A dual luciferase reporter assay was performed to confirm the binding relationship among MALAT1, miR-494, and specificity protein 1 (SP1). Expression levels of MALAT1, SP1, and VEGFA were elevated and miR-494 was suppressed in MC3T3-E1 cells after culture in osteogenic medium. MALAT1 knockdown suppressed the osteogenic differentiation of MC3T3-E1, since ALP activity, mineralized nodules, and expression of the osteodifferentiated markers runt-related transcription factor 2 and osterix were restrained. In addition, MALAT1 silencing inhibited angiogenesis during bone regeneration, as the proliferation, migration, and capillary tube formation of human umbilical vein endothelial cells were blocked. Furthermore, miR-494 was directly targeted by MALAT1 and regulated the SP1/Toll-like receptor 2 (TLR2)/bone morphogenetic protein 2 (BMP2) axis by targeting SP1. Furthermore, miR-494 overexpression inhibited angiogenesis and osteogenic differentiation. Moreover, SP1 overexpression or miR-494 inhibition rescued the regulatory effect of sh-MALAT1 on angiogenesis and osteogenic differentiation. Taken together, these findings indicate that MALAT1 promotes angiogenesis and osteogenic differentiation by targeting miR-494 and activating the SP1/TLR2/BMP2 pathway, suggesting a novel target for bone regeneration therapy by promoting angiogenesis.

To study the accuracy of 3D printing implant-guided anterior tooth implantation under flap or flapless surgery.Twenty-one cases (32 teeth) with missing teeth were divided into two groups: tooth implantation on the maxillary models under flap surgery (FP group) and tooth implantation on the maxillary models under flapless surgery (FPS group). A dental implant guide was designed and used in the two groups. The actual position of the dental implants in the two groups was compared with the preplanned deviation values of implant top, bottom, vertical distance, and angle deviation. SPSS 19.0 software was used for statistical analysis.The deviation values of implant top, bottom, vertical distance, and angle were significantly lower in the FP group than in the FPS group (P0.05).High accuracy of tooth implantation can be realized by using the 3D printing implant guide. The different surgical methods influence the precision of tooth implantation. Clinicians can choose the surgery reasonably depending on the actual situation.目的 比较3D打印种植导板引导前牙牙种植在不同术式下的精度。方法 选择21例（32个牙位）牙缺失患者，制作仿真翻瓣与不翻瓣颌骨模型，分为翻瓣组（FP组）与不翻瓣组（FPS组），分别设计制作牙种植导板，比较两组牙种植体实际位置与术前规划在顶端、底端、垂直向距离的偏差值和角度偏差值。采用SPSS 19.0软件对数据进行统计学分析。结果 FPS组与FP组种植体顶端、底端、垂直向距离偏差值和角度偏差值的差异均有统计学意义（P0.05）；与FPS组相比，FP组偏差值更小，精度更高。结论 3D打印种植导板可提高牙种植的精确性，翻瓣与不翻瓣的不同术式对牙种植精度有一定的影响，临床医生可根据实际情况合理选择术式。.