ABSTRACT
Objective:To study the alveolar bone morphology in the anterior teeth area of the skeletal Class Ⅱ malocclusion subjects with different vertical skeletal types.Methods:64 patients with skeletal Class Ⅱ malocclusion and 15 subjects with normal occlusion were included.The alveolar bone structure of the anterior teeth were observed using CBCT.Results:The labial and lingual alveolar bone height and the alveolar bone thickness of the incisors of the patients were much lower than those of the normal controls.The height of labial and lingual alveolar bone and the alveolar bone thickness of anterior teeth in high-angle subgroup were lower than those in low-angle subgroup.Conclusion:The thickness of the anterior teeth alveolar bone of skeletal Class Ⅱ malocclusion is low,espe-cially in the high-angle group.
ABSTRACT
Objective:To investigate the craniofacial features in patients with cleidocranial dysplasia (CCD).Methods:The facial features,cervical vertebral bone age and skeletal abnormalities of 8 patients with CCD were studied by analyzing facial photos,cephalo-metric and panoramic radiographs.Results:4 patients were in the early growth stage and the other 4 in the late period of development. The bossing forehead and inclined eye fissure were observed in all patients,but underdevelopment of midfaces were not obviously pres-ented in younger patients.Morphological abnormalities of craniofacial bones,such as ascending ramus,coronoid process,nasal bones and disappearence of gonial angle were observed in all patients.Conclusion:Some craniofacial malformations in patients with CCD may be presented earlier than underdeveloped midface,which can be helpful for early diagnosis of CCD.
ABSTRACT
BACKGROUND:Human bone marrow cells-derived extracellular matrix can promote proliferation of human periodontal ligament stem cells and maintain stem cellproperties. OBJECTIVE:To preliminarily investigate the effect of human bone marrow cells-derived extracellular matrix on the proliferation of human periodontal ligament stem cells. METHODS:Human periodontal ligament stem cells and bone marrow cells were separately derived from human periodontal tissue and jaw bone marrow, and human bone marrow cells-derived extracellular matrix was prepared. Human periodontal ligament stem cells were cultured and purified using limited dilution cloning method, and transmission electron microscope was used for ultrastructure observation. Human periodontal ligament stem cells at passage 2 were cultured with human bone marrow cells-derived extracellular matrix and normal culture medium (control group). The cellcounting kit-8 and flow cytometry were used to determine the proliferation potential of human periodontal ligament stem cells cultured on human bone marrow cells-derived extracellular matrix. RESULTS AND CONCLUSION:Compared with the control group, human periodontal ligament stem cells cultured on human bone marrow cells-derived extracellular matrix had a superior capacity of proliferation (P<0.05), and the cells met their morphological and biological characteristics, and grew in good conditions. Human bone marrow cells-derived extracellular matrix is a promising matrix for large-scale expanding human periodontal ligament stem cells for future use in stem cel-based therapy.
ABSTRACT
BACKGROUND:Many studies have showed that enough blood supply is an essential condition of bone repair and regeneration. OBJECTIVE:To construct the endothelial progenitor cells/bone marrow mesenchymal stem cells (EPCs/BMSCs) composite sheet. METHODS:After isolation and culture, EPCs and BMSCs were co-cultured directly to form EPCs/BMSCs sheet by cellsheet-inducing medium. After 10 days of induction, the sheet was investigated by gross observation, inverted microscope and hematoxylin-eosin staining. The distribution and communication of EPCs and BMSCs during the process of cellsheet induction were observed after the fluorescence labeling separately. Alkaline phosphatase assay and alizarin red staining were applied to examine the ability of osteogenic differentiation of EPCs/BMSCs sheet. RESULTS AND CONCLUSION:EPCs/BMSCs sheet was harvested after 10-day induction. Cel-cellcontact between EPCs and BMSCs could be observed during the process of the cellsheet preparation. The harvested sheet was composed of multiple layers of cells and cel-produced extracellular matrix. Alkaline phosphatase assay and alizarin red staining both demonstrated that EPCs/BMSCs sheet had good osteogenic differentiation ability. These results suggested that EPCs/BMSCs sheet can be constructed successful y, and the sheet has strong osteogenic differentiation capability in vitro, providing the foundation for the repair of bone defects.
ABSTRACT
BACKGROUND:Extracellular matrix can simulate microenvironment and make the stem cells proliferate maintaining the characteristics of stem cells wel in vitro. OBJECTIVE:To prepare the extracellular matrix from human bone marrow cells and to analyze its microstructure and composition preliminarily. METHODS:Human bone marrow cells of passage 4 were cultured for 14 days, and the induction medium was used during the last 8 days. After decellularization, cells were removed to prepare human bone marrow cells-derived extracellular matrix. The surface morphology of human bone marrow cells-derived extracellular matrix was observed by inverted microscope and scanning electron microscope. Changes of col agen I and biglycan before and after decellularization were observed by immunofluorescence staining. Human periodontal ligament stem cells were seeded onto human bone marrow cells-derived extracellular matrix, fibronectin coated 6-wel plate and normal culture plate to compare the influence of different matrix on cellmorphology and adhesion. RESULTS AND CONCLUSION:We obtained intact human bone marrow cells-derived extracellular matrix by chemical combined with physical decellularization. The structure and amount of col agen I and biglycan had not been compromised dramatical y after decellularization. Human periodontal ligament stem cells growing on the human bone marrow cells-derived extracellular matrix developed in accordance with the orbit of the extracellular matrix, differing from the original cellmorphology. There were more human periodontal ligament stem cells adhering to the extracellular matrix during the same time. These findings indicate that effective decellularization can produce intact the extracellular matrix membrane without destroying its microstructure. Extracellular matrix protein is not compromised due to decellularization. The extracellular matrix affects cellmorphology and promotes celladhesion. We can use the extracellular matrix model to simulate stem cellmicroenvironment and thereafter, acquire a large number of adult stem cells with high quality in vitro.