Five theories shed lights on the potential mechanisms of aging:somatic mutations,telomere loss,mitochondrial defects,and accumulation of altered proteins inside proteasomes.The existence of a program of aging is not y...Five theories shed lights on the potential mechanisms of aging:somatic mutations,telomere loss,mitochondrial defects,and accumulation of altered proteins inside proteasomes.The existence of a program of aging is not yet identified,but overlaps with a program for risks of death.On the other hand,organisms are programmed for survival,which ultimately fails.This failure results in aging,notabily,focusing on alterations of specific genes.Irregular examinations,dysfunctions,insufficient use of fluoride,and removable partial dentures,are favoring the formation of caries and periodontal pathologies.Oral lesions are due to local trauma,related gingival recession,and formation of pockets.They are associated to insufficient removal of food/plaque.Epithelial thinning,and reduction of extracellular matrix components,lead to plications and foldings of the mucosal surface,and subsequently to bacterial colonization.Geriatric dentistry(or gerodontology)is an increasing field of dentistry,mostly associated with the growing percentage of patients over 80+years.展开更多
Dental pulp stem cells(DPSCs) are thought to contribute to reparative dentin formation, and that they may correspond to heterogenous populations of precursor cells or represent distinct differentiation stages along th...Dental pulp stem cells(DPSCs) are thought to contribute to reparative dentin formation, and that they may correspond to heterogenous populations of precursor cells or represent distinct differentiation stages along the odontoblastic lineage. DPSCs share many similarities with mesenchymal stem cells of the bone marrow(BMSCs). It appears that the distribution of tissue stem cells is not random and, within the dental pulp, there are potentially several distinct niches of stem/progenitor cells. In addition to DPSCs, other dental stem cell populations have been isolated. As for DPSCs, further studies are still needed to evaluate their potential of differentiation and their regenerative activity. Up today,(1) the formal demonstration that pulpal resident stem cells are actually the reparative dentin-forming cells recruited in response to injury is still lacking; and(2) the origin, localization and precise identity of odontogenic stem cells remain largely unknown. Dental clonal cell lines may represent valuable tool to answer some fontamental questions concerning the dental stem cell biology. Altogether, the presence of dental cell populations displaying stem cell properties has opened new paths for considering regenerative therapies. This might be aprerequisite to design alternative strategies for capping and endodontic treatment, using stem cells.展开更多
文摘Five theories shed lights on the potential mechanisms of aging:somatic mutations,telomere loss,mitochondrial defects,and accumulation of altered proteins inside proteasomes.The existence of a program of aging is not yet identified,but overlaps with a program for risks of death.On the other hand,organisms are programmed for survival,which ultimately fails.This failure results in aging,notabily,focusing on alterations of specific genes.Irregular examinations,dysfunctions,insufficient use of fluoride,and removable partial dentures,are favoring the formation of caries and periodontal pathologies.Oral lesions are due to local trauma,related gingival recession,and formation of pockets.They are associated to insufficient removal of food/plaque.Epithelial thinning,and reduction of extracellular matrix components,lead to plications and foldings of the mucosal surface,and subsequently to bacterial colonization.Geriatric dentistry(or gerodontology)is an increasing field of dentistry,mostly associated with the growing percentage of patients over 80+years.
文摘Dental pulp stem cells(DPSCs) are thought to contribute to reparative dentin formation, and that they may correspond to heterogenous populations of precursor cells or represent distinct differentiation stages along the odontoblastic lineage. DPSCs share many similarities with mesenchymal stem cells of the bone marrow(BMSCs). It appears that the distribution of tissue stem cells is not random and, within the dental pulp, there are potentially several distinct niches of stem/progenitor cells. In addition to DPSCs, other dental stem cell populations have been isolated. As for DPSCs, further studies are still needed to evaluate their potential of differentiation and their regenerative activity. Up today,(1) the formal demonstration that pulpal resident stem cells are actually the reparative dentin-forming cells recruited in response to injury is still lacking; and(2) the origin, localization and precise identity of odontogenic stem cells remain largely unknown. Dental clonal cell lines may represent valuable tool to answer some fontamental questions concerning the dental stem cell biology. Altogether, the presence of dental cell populations displaying stem cell properties has opened new paths for considering regenerative therapies. This might be aprerequisite to design alternative strategies for capping and endodontic treatment, using stem cells.
