PubMed | Jinan Stomatological Hospital Jinan, Shandong University and Qingdao University
Type: Journal Article | Journal: International journal of clinical and experimental pathology | Year: 2015
Pulp regeneration caused by endogenous cells homing has become the new research spot in endodontics. However, the source of functional cells that are involved in and contributed to the reconstituting process has not been identified. In this study, the possible role of systemical BMSC in pulp regeneration and the effect of stromal cell-derived factor-1 (SDF-1) on stem cell recruitment and angiogenesis were evaluated. 54 mice were divided into three groups: SDF-1 group (subcutaneous pockets containing roots with SDF-1 absorbed neutralized collagen gel and the green fluorescent protein (GFP) positive BMSCs transplantation via the tail vein), SDF-1-free group (pockets containing roots with gel alone and GFP + BMSCs transplantation) and Control group (pockets containing roots with gel alone). The animals were sacrificed after the roots were implanted into subcutaneous pockets for 3 weeks. Histomorphometric analysis was performed to evaluate the regenerated tissue in the canal by hematoxylin and eosin (HE) staining. The homing of the transplanted BMSCs was monitored with a fluorescence microscope and immunohistochemical analysis. The expression of ALP in new formed tissue was detected immunohistochemically. Dental-pulp-like tissue and new vessels were regenerated and GFP-positive BMSCs and expression of ALP could be observed in both SDF-1 group and SDF-1-free group. Furthermore, more GFP+ cells, stronger expression of ALP and stronger angiogenesis were found in the SDF-1 group than in the SDF-1-free group. To conclude, systemic BMSC can home to the root canal and participate in dental-pulp-like tissue regeneration. Intracanal application of SDF-1 may enhance BMSC homing efficiency and angiogenesis.
PubMed | Jinan Stomatological Hospital Jinan and Shandong University
Type: Journal Article | Journal: International journal of clinical and experimental pathology | Year: 2016
To investigate the impact of hypoxia on the expression of receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG) in human periodontal ligament cells (hPDLCs) in vitro. hPDLCs were incubated in a hypoxic atmosphere of 2% O2, 5% CO2, 94% N2 at 37C for 6, 12, 24 and 48 h. After that, cell proliferation assay was determined using CCK-8 technique. SP immunocytochemistry method was performed to trace the expression of hypoxia-inducible factor 1 alpha (HIF-1) in hPDLCs. The expression levels of RANKL and OPG were investigated using real-time PCR and ELISA. As a control, the cells were incubated at normoxic conditions of 20% O2, 5% CO2, 75% N2. All results were analyzed using one-way ANOVA at a significant level of P=0.05. OPG mRNA and protein levels were down-regulated meanwhile RANKL mRNA and soluble RANKL (sRANKL) protein levels were up-regulated after stimulated by hypoxia. The relative RANKL/OPG expression ratios were increased in both mRNA and protein levels. The expression of RANKL mRNA and sRANKL protein levels was enhanced significantly (P<0.05) under the hypoxia conditions at 12 h, 24 h and 48 h while OPG mRNA and protein were reduced significantly (P<0.05) at 12 h, 24 h and 48 h. Hypoxia can affect the expression of RANKL and OPG in hPDLCs, which constitute an important pathogenic event in the alveolar bone resorption. Lack of oxygen in periodontal tissue may accelerate the development of periodontitis.
PubMed | Jinan Stomatological Hospital Jinan
Type: Journal Article | Journal: Shanghai kou qiang yi xue = Shanghai journal of stomatology | Year: 2014
To evaluate the restorative effectiveness of fiber post versus metal screw post through systematical review.Randomized controlled trials (RCTs) data from the establishment of the database up to June 2013 were searched from MEDLINE (Ovid), PubMed, The Cochrane Library, Embase, Wanfang Data, VIP, CNKI and CBM using the designed strategy. After data extraction and quality review of the retrieved articles by two independent investigators, the softwares of RevMan 5.1.0 and GRAED profiler 3.2.2 were employed to process data analysis.Ten RCTs were finally included, of which 1 was English literature and 9 were Chinese literatures. Meta analysis suggested that the survival rate of repair of adult and young permanent teeth was significantly higher using fiber post than metal screw post [RR=1.21,95%CI(1.13,1.30), P<0.01,RR=1.21,95%CI(1.10,1.34), P<0.01], and the results root fracture rate was significantly lower [RR=0.16,95%CI(0.05,0.48),P=0.001]. No significant difference was found in the rate of post-core fall off [RR=0.76,95%CI(0.33,1.73), P>0.05] and gingivitis [RR=0.71, 95%CI(0.27,1.88), P>0.05]. All outcomes were of low quality in the GRADE system.Compared with metal screw post, the survival rate is significantly higher and the root fracture rate is significantly lower by using fiber post. However, the conclusion is limited by lack of relevant studies, small sample sizes, inadequate quality and diversified methodology. Further study is needed by employing more well-designed, large-sample and multi-center RCTs to verify the conclusion.