Browsing by Subject "Dental pulp"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Publication
    Open Access
    Biological action of bleaching agents on tooth structure: A review
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2024) Bragança Aragão, Walessa Alana; Santos Chemelo, Victória; de Melo Alencar, Cristiane; Martins Silva, Cecy; Pessanha, Sofia; Reis, Alessandra; de Souza Rodrigues, Renata Duarte; Rodrigues Lima, Rafael
    The use of bleaching agents to remove stains is one of the main dental procedures to improve the aesthetics of teeth. This review presents the main agents used for tooth whitening, existing clinical protocols, and the structural changes that may occur through their use. The main bleaching agents consist of hydrogen peroxide and carbamide peroxide, which are used in bleaching techniques for vital teeth. These techniques can be performed in the office by a professional or by the individual in a home environment under professional guidance. Bleaching agents come in a variety of concentrations and there are over-the-counter products available on the market with lower concentrations of hydrogen peroxide. Due to the chemical characteristics of the agents, changes in the organic and inorganic content of the tooth structure can be observed. These changes are related to morphological changes characterized by increased permeability and surface roughness, such changes compromise the mechanical resistance of the tooth. Furthermore, bleaching agents can promote molecular changes after reaching the dental pulp, resulting in oxidative stress of pulp cells and the release of proinflammatory mediators. Despite the bleaching effectiveness, tooth sensitivity is considered the main side effect of use. Therefore, among the heterogeneity of protocols, those that used the bleaching agent for a prolonged time and in lower concentrations presented more harmful effects on the tooth structure.
  • Thumbnail Image
    Publication
    Open Access
    Human dental Pulp stem cells exhibit different biological behaviours in response to commercial bleaching products
    (MDPI, 2018-06-27) Llena, Carmen; Collado-González, Mar; Tomás Catalá, Christopher Joseph; García Bernal, David; Oñate Sánchez, Ricardo Elías; Rodríguez Lozano, Francisco Javier; Forner, Leopoldo; Biología Celular e Histología
    The purpose of this study was to evaluate the diffusion capacity and the biological effects of different bleaching products on human dental pulp stem cells (hDPSCs). The bleaching gel was applied for 90, 30 or 15 min to enamel/dentine discs that adapted in an artificial chamber. The diffusion of hydrogen peroxide (HP) was analysed by fluorometry and the diffusion products were applied to hDPSCs. Cell viability, cell migration and cell morphology assays were performed using the eluates of diffusion products. Finally, cell apoptosis and the expression of mesenchymal stem cell markers were analysed by flow cytometry. Statistical analysis was performed using analysis of variance and Kruskal–Wallis or Mann–Whitney tests ( < 0.05). Significant reductions of approximately 95% in cell viability were observed for the 3 x 15 min groups (p < 0.001), while 1 x 30 min of PerfectBleach and 1 x 90 min of PolaNight resulted in reductions of 50% and 60% in cell viability, respectively (p < 0.001). Similar results were obtained in the migration assay. Moreover, the 3 x 15 min group was associated with cell morphology alterations and reductions of >70% in cell live. Finally, hDPSCs maintained their mesenchymal phenotype in all conditions. Similar concentrations of carbamide peroxide (CP) and HP in different commercial products exhibited different biological effects on hDPSCs.
  • Thumbnail Image
    Publication
    Open Access
    Ischemic culture of dental pulp-derived cells is a useful model in which to investigate mechanisms of post-ischemic tissue recovery
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2013) Agata, Hideki; Sumita, Yoshinori; Asahina, Izumi; Tojo, Arinobu; Kagami, Hideaki
    Dental pulp is a soft tissue characterized by unique regenerative properties. It is located in the center of each tooth, and is surrounded by hard tissue (dentin). Vascular access is limited to a small foramen at the root apex. Because of this anatomical limitation, dental pulp can easily lose its blood supply, causing the tissue to become ischemic. This occurs, for example, when a tooth is dislocated by traumatic injury or is subjected to inflammation. Since ischemia is caused by a critical shortage of oxygen and nutrients, ischemic damage is usually irreversible, even when the ischemic event is transient. However, unlike ischemia-sensitive organs such as the brain and heart, dental pulp is relatively ischemia-resistant, and recovers from ischemic injury by regenerating damaged tissue. The mechanisms by which this regeneration occurs are poorly understood, but are being investigated in cell culture models that mimic in vivo ischemic conditions using a combination of hypoxia and nutrient deprivation. Here, we review the use of ischemic cell culture to investigate the mechanisms of post-ischemic dental pulp tissue recovery.
  • Thumbnail Image
    Publication
    Open Access
    Isolation of pluripotent stem cells from human third molar dental pulp
    (Editores F. Hernandez y Juan F. Madrid. Murcia, Universidad de Murcia, Departamento de Biologia Celular e Histologia, 2011) Atari, M.; Barajas, M.; Hernández-Alfaro, F.; Gil, C.; Fabregat, M.; Ferrés Padró, E.; Giner, L.; Casals, N.
    Potent stem/progenitor cells have been isolated from normal human dental pulps, termed dental pulp stem cells (DPSCs). However, no study has described the presence of stem cell populations in human dental pulp from the third molar with embryonic phenotypes. The dental pulp tissue was cultured in media with the presence of LIF, EGF, and PDGF. In the present study, we describe a new population of pluripotent stem cells that were isolated from dental pulp (DPPSC). These cells are SSEA-4+, Oct4+, Nanog+, FLK-1+, HNF3beta+, Nestin+, Sox2+, Lin28+, c-Myc+, CD13+, CD105+, CD34- , CD45- , CD90low, CD29+, CD73low, STRO-1low and CD146- . We have investigated by SEM analysis and q-RT-PCR the capacity of DPPSCs to 3D differentiate in vitro using the Cell Carrier 3D glass scaffold into tissues that have similar characteristics to embryonic mesoderm and endoderm layers. These data would support the use of these cells, which are derived from an easily accessible source and can be used in future regeneration protocols for many tissue types that differentiate from the three embryonic layers.
  • Thumbnail Image
    Publication
    Open Access
    Pinocytotic vacuoles in human dental pulp capillaries
    (Murcia : F. Hernández, 1993) Lyroudia, K.I.; Economou, L.; Manthos, A.; Zervas, P.; Albanou, A.; Foroglou, Ch.
    Dental pulp capillaries were studied in human. They were of the cantinuous type, with the exception of a small number which were of the fenestrated type, located in the vicinity of the odontoblasts. A characteristic morphological peculiarity was found in the endothelial cells. In places there was a large quantity of multisized vacuoles. The vacuoles were evidently of pinocytotic origin, and their content was emptied into the extracapillary space. The initiation of their formation was indicated by the creation of cytoplasmic flaps, which could not be characterised as typical pseudopodia, and which in cross sections resembled microvilli. The flaps engulfed a quantity of plasma and then, after bending over, their edge fused with the cell, creating a vacuole. The vacuole, after being moved abluminally, was emptied into the pericapillary area by exocytosis. There was indication that flaps created at the borders of the endothelial cells (flanges) acted likewise, transporting vacuoles through the intercellular spaces. Micropinocytosis, was a distinctly different phenomenon, contributing, to a very small degree, to the intracellular enlargement of the vacuoles. It seems that this vacuolar mechanism of transportation serves an augmented metabolic need of the surrounding tissue.