The Experts below are selected from a list of 213 Experts worldwide ranked by ideXlab platform
B Senguuven - One of the best experts on this subject based on the ideXlab platform.
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odontoblast like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet rich plasma and enamel matrix derivative a histomorphometric evaluation
International Endodontic Journal, 2012Co-Authors: Ekim Onur Orhan, Murat Maden, B SenguuvenAbstract:Orhan EO, Maden M, Senguuven B. Odontoblast-like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma and enamel matrix derivative: a histomorphometric evaluation. International Endodontic Journal, 45, 317–325, 2012. Abstract Aim To collect quantitative information about the numbers of odontoblast-like cells and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma (PRP) and enamel matrix derivative (EMD). Methodology The experiment was conducted on 36 Wistar albino rats and a total of 144 incisor teeth. Calcium hydroxide, mineral trioxide aggregate, PRP and EMD were applied as direct capping agents on the pulps of 96 incisors (n = 24). Positive and negative control groups were created on the remaining 48 incisors. The teeth were extracted on the 7th and 28th days. After routine histological preparation, cross-sections were stained with haematoxylin and eosin. The numbers of the odontoblast-like cells were measured histomorphometrically on day 7 and day 28. The thickness of the Reparative Dentine was also measured. The number of odontoblast-like cells was also measured beneath the Dentine bridge. The normal distribution of all data was tested with the Mann–Whitney U test. The statistical differences between groups were analysed using the Kruskal–Wallis test. Results The mean number of odontoblast-like cells increased between day 7 and 28 following pulp exposure (P > 0.01) in all groups except for the EMD group (P 0.01). Conclusions Reparative Dentine formation was observed, but with no significant difference between the groups. Odontoblast-like cells were observed in association with the outcome of pulps capped with PRP and EMD. PRP and EMD are possible capping agents that influence the thickness of Reparative Dentine formation.
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odontoblast like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet rich plasma and enamel matrix derivative a histomorphometric evaluation
International Endodontic Journal, 2012Co-Authors: Ekim Onur Orhan, Murat Maden, B SenguuvenAbstract:AIM: To collect quantitative information about the numbers of odontoblast-like cells and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma (PRP) and enamel matrix derivative (EMD). METHODOLOGY: The experiment was conducted on 36 Wistar albino rats and a total of 144 incisor teeth. Calcium hydroxide, mineral trioxide aggregate, PRP and EMD were applied as direct capping agents on the pulps of 96 incisors (n = 24). Positive and negative control groups were created on the remaining 48 incisors. The teeth were extracted on the 7th and 28th days. After routine histological preparation, cross-sections were stained with haematoxylin and eosin. The numbers of the odontoblast-like cells were measured histomorphometrically on day 7 and day 28. The thickness of the Reparative Dentine was also measured. The number of odontoblast-like cells was also measured beneath the Dentine bridge. The normal distribution of all data was tested with the Mann-Whitney U test. The statistical differences between groups were analysed using the Kruskal-Wallis test. RESULTS: The mean number of odontoblast-like cells increased between day 7 and 28 following pulp exposure (P > 0.01) in all groups except for the EMD group (P 0.01). CONCLUSIONS: Reparative Dentine formation was observed, but with no significant difference between the groups. Odontoblast-like cells were observed in association with the outcome of pulps capped with PRP and EMD. PRP and EMD are possible capping agents that influence the thickness of Reparative Dentine formation.
Paul T Sharpe - One of the best experts on this subject based on the ideXlab platform.
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gsk3 inhibitor induced dentinogenesis using a hydrogel
Journal of Dental Research, 2021Co-Authors: Lucia K Zaugg, A Alaohali, Christoph Salzlechner, F Suzano, Ana Martinez, Eileen Gentleman, Paul T SharpeAbstract:Small-molecule drugs targeting glycogen synthase kinase 3 (GSK3) as inhibitors of the protein kinase activity are able to stimulate Reparative Dentine formation. To develop this approach into a viable clinical treatment for exposed pulp lesions, we synthesized a novel, small-molecule noncompetitive adenosine triphosphate (ATP) drug that can be incorporated into a biodegradable hydrogel for placement by syringe into the tooth. This new drug, named NP928, belongs to the thiadiazolidinone (TDZD) family and has equivalent activity to similar drugs of this family such as tideglusib. However, NP928 is more water soluble than other TDZD drugs, making it more suitable for direct delivery into pulp lesions. We have previously reported that biodegradable marine collagen sponges can successfully deliver TDZD drugs to pulp lesions, but this involves in-theater preparation of the material, which is not ideal in a clinical context. To improve surgical handling and delivery, here we incorporated NP928 into a specifically tailored hydrogel that can be placed by syringe into a damaged tooth. This hydrogel is based on biodegradable hyaluronic acid and can be gelled in situ upon dental blue light exposure, similarly to other common dental materials. NP928 released from hyaluronic acid-based hydrogels upregulated Wnt/β-catenin activity in pulp stem cells and fostered Reparative Dentine formation compared to marine collagen sponges delivering equivalent concentrations of NP928. This drug-hydrogel combination has the potential to be rapidly developed into a therapeutic procedure that is amenable to general dental practice.
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macrophage modulation of dental pulp stem cell activity during tertiary dentinogenesis
Scientific Reports, 2020Co-Authors: Vitor C M Neves, Val Yianni, Paul T SharpeAbstract:The interaction between immune cells and stem cells is important during tissue repair. Macrophages have been described as being crucial for limb regeneration and in certain circumstances have been shown to affect stem cell differentiation in vivo. Dentine is susceptible to damage as a result of caries, pulp infection and inflammation all of which are major problems in tooth restoration. Characterising the interplay between immune cells and stem cells is crucial to understand how to improve natural repair mechanisms. In this study, we used an in vivo damage model, associated with a macrophage and neutrophil depletion model to investigate the role of immune cells in Reparative Dentine formation. In addition, we investigated the effect of elevating the Wnt/β-catenin pathway to understand how this might regulate macrophages and impact upon Wnt receiving pulp stem cells during repair. Our results show that macrophages are required for dental pulp stem cell activation and appropriate Reparative Dentine formation. In addition, pharmacological stimulation of the Wnt/β-catenin pathway via GSK-3β inhibitor small molecules polarises macrophages to an anti-inflammatory state faster than inert calcium silicate-based materials thereby accelerating stem cell activation and repair. Wnt/β-catenin signalling thus has a dual role in promoting Reparative Dentine formation by activating pulp stem cells and promoting an anti-inflammatory macrophage response.
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axin2 expressing cells differentiate into Reparative odontoblasts via autocrine wnt β catenin signaling in response to tooth damage
Scientific Reports, 2017Co-Authors: Rebecca Babb, Dhivya Chandrasekaran, Vitor De Carvalho Moreno Das Neves, Paul T SharpeAbstract:In non-growing teeth, such as mouse and human molars, primary odontoblasts are long-lived post-mitotic cells that secrete Dentine throughout the life of the tooth. New odontoblast-like cells are only produced in response to a damage or trauma. Little is known about the molecular events that initiate mesenchymal stem cells to proliferate and differentiate into odontoblast-like cells in response to Dentine damage. The Reparative and regenerative capacity of multiple mammalian tissues depends on the activation of Wnt/β-catenin signaling pathway. In this study, we investigated the molecular role of Wnt/β-catenin signaling pathway in Reparative dentinogenesis using an in vivo mouse tooth damage model. We found that Axin2 is rapidly upregulated in response to tooth damage and that these Axin2-expressing cells differentiate into new odontoblast-like cells that secrete Reparative Dentine. In addition, the Axin2-expressing cells produce a source of Wnt that acts in an autocrine manner to modulate Reparative dentinogenesis.
Ekim Onur Orhan - One of the best experts on this subject based on the ideXlab platform.
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odontoblast like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet rich plasma and enamel matrix derivative a histomorphometric evaluation
International Endodontic Journal, 2012Co-Authors: Ekim Onur Orhan, Murat Maden, B SenguuvenAbstract:Orhan EO, Maden M, Senguuven B. Odontoblast-like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma and enamel matrix derivative: a histomorphometric evaluation. International Endodontic Journal, 45, 317–325, 2012. Abstract Aim To collect quantitative information about the numbers of odontoblast-like cells and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma (PRP) and enamel matrix derivative (EMD). Methodology The experiment was conducted on 36 Wistar albino rats and a total of 144 incisor teeth. Calcium hydroxide, mineral trioxide aggregate, PRP and EMD were applied as direct capping agents on the pulps of 96 incisors (n = 24). Positive and negative control groups were created on the remaining 48 incisors. The teeth were extracted on the 7th and 28th days. After routine histological preparation, cross-sections were stained with haematoxylin and eosin. The numbers of the odontoblast-like cells were measured histomorphometrically on day 7 and day 28. The thickness of the Reparative Dentine was also measured. The number of odontoblast-like cells was also measured beneath the Dentine bridge. The normal distribution of all data was tested with the Mann–Whitney U test. The statistical differences between groups were analysed using the Kruskal–Wallis test. Results The mean number of odontoblast-like cells increased between day 7 and 28 following pulp exposure (P > 0.01) in all groups except for the EMD group (P 0.01). Conclusions Reparative Dentine formation was observed, but with no significant difference between the groups. Odontoblast-like cells were observed in association with the outcome of pulps capped with PRP and EMD. PRP and EMD are possible capping agents that influence the thickness of Reparative Dentine formation.
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odontoblast like cell numbers and Reparative Dentine thickness after direct pulp capping with platelet rich plasma and enamel matrix derivative a histomorphometric evaluation
International Endodontic Journal, 2012Co-Authors: Ekim Onur Orhan, Murat Maden, B SenguuvenAbstract:AIM: To collect quantitative information about the numbers of odontoblast-like cells and Reparative Dentine thickness after direct pulp capping with platelet-rich plasma (PRP) and enamel matrix derivative (EMD). METHODOLOGY: The experiment was conducted on 36 Wistar albino rats and a total of 144 incisor teeth. Calcium hydroxide, mineral trioxide aggregate, PRP and EMD were applied as direct capping agents on the pulps of 96 incisors (n = 24). Positive and negative control groups were created on the remaining 48 incisors. The teeth were extracted on the 7th and 28th days. After routine histological preparation, cross-sections were stained with haematoxylin and eosin. The numbers of the odontoblast-like cells were measured histomorphometrically on day 7 and day 28. The thickness of the Reparative Dentine was also measured. The number of odontoblast-like cells was also measured beneath the Dentine bridge. The normal distribution of all data was tested with the Mann-Whitney U test. The statistical differences between groups were analysed using the Kruskal-Wallis test. RESULTS: The mean number of odontoblast-like cells increased between day 7 and 28 following pulp exposure (P > 0.01) in all groups except for the EMD group (P 0.01). CONCLUSIONS: Reparative Dentine formation was observed, but with no significant difference between the groups. Odontoblast-like cells were observed in association with the outcome of pulps capped with PRP and EMD. PRP and EMD are possible capping agents that influence the thickness of Reparative Dentine formation.
Marcio Cajazeira Aguiar - One of the best experts on this subject based on the ideXlab platform.
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immunocytochemical detection of Dentine matrix protein 1 in experimentally induced reactionary and Reparative Dentine in rat incisors
Archives of Oral Biology, 2010Co-Authors: Marcio Cajazeira Aguiar, Victor E AranachavezAbstract:Abstract Objective Although the general mechanisms of dentinogenesis are understood, several aspects regarding tertiary Dentine formation still deserve investigation, especially regarding the presence and distribution of some noncollagenous matrix proteins. As Dentine matrix protein 1 (DMP 1) is present in primary Dentine, it is possible that this protein may also be present in the Dentine matrix secreted after injury, but there are no immunocytochemical studies attempting its detection in tertiary Dentine. The aim of this study was to examine the ultrastructural immunolocalization of DMP 1 in the tertiary Dentine after extrusion of the rat incisor. Study design Upper incisors were extruded 3 mm and then repositioned into their sockets. After several periods, the incisors were fixed and processed for transmission electron microscopy and for immunocytochemistry for DMP 1. Results Extrusion yielded both types of tertiary Dentine, which varied in aspect and related cells. DMP 1 was found in the mineralized matrix of all types of Dentine, presenting high affinity for collagen, but rare colloidal gold particles over preDentine. DMP 1 was evident in the supranuclear region and inside the nucleus of some odontoblast-like cells. Conclusion The observed association between DMP 1 and collagen seem to be essential for reactionary and Reparative Dentine formation.
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ultrastructural and immunocytochemical analyses of osteopontin in reactionary and Reparative Dentine formed after extrusion of upper rat incisors
Journal of Anatomy, 2007Co-Authors: Marcio Cajazeira Aguiar, Victor E AranachavezAbstract:Reactionary Dentine and Reparative Dentine are two strategies used by the Dentine-pulp complex to respond to injury. The reactionary Dentine is secreted by original odontoblasts, while the Reparative Dentine is formed by odontoblast-like cells. Osteopontin (OPN) is a non-collagenous protein usually present in the repair of mineralized tissues. It is likely to be present in newly formed Dentine but there are no studies attempting to detect it in reactionary and Reparative Dentine. The aim of the present study was to examine the ultrastructural characteristics, as well as the presence and distribution of OPN in reactionary and Reparative Dentine by provoking extrusion of the rat incisor. The right upper incisors of 3-month-old male rats were extruded 3 mm and then repositioned into their original sockets. At 3, 7, 10, 15, 20, 30 and 60 days after surgery, the incisors were fixed in glutaraldehyde-formaldehyde and then processed for scanning and transmission electron microscopy and for immunocytochemistry for OPN. After extrusive trauma, the Dentine-pulp interface showed the presence of reactionary and Reparative Dentine, which varied in aspect, thickness and related cells. OPN was not detected in the physiological and reactionary Dentine, while it was strongly immunoreactive in the matrix that surrounded the entrapped cells of Reparative Dentine. In addition, original odontoblasts subjacent to the physiological Dentine contained OPN in their Golgi region. The present findings showed that Reparative Dentine shares some structural characteristics with primary bone, especially in relation to its OPN content. The odontoblast-like cells resemble osteoblasts rather than odontoblasts.
Victor E Aranachavez - One of the best experts on this subject based on the ideXlab platform.
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immunocytochemical detection of Dentine matrix protein 1 in experimentally induced reactionary and Reparative Dentine in rat incisors
Archives of Oral Biology, 2010Co-Authors: Marcio Cajazeira Aguiar, Victor E AranachavezAbstract:Abstract Objective Although the general mechanisms of dentinogenesis are understood, several aspects regarding tertiary Dentine formation still deserve investigation, especially regarding the presence and distribution of some noncollagenous matrix proteins. As Dentine matrix protein 1 (DMP 1) is present in primary Dentine, it is possible that this protein may also be present in the Dentine matrix secreted after injury, but there are no immunocytochemical studies attempting its detection in tertiary Dentine. The aim of this study was to examine the ultrastructural immunolocalization of DMP 1 in the tertiary Dentine after extrusion of the rat incisor. Study design Upper incisors were extruded 3 mm and then repositioned into their sockets. After several periods, the incisors were fixed and processed for transmission electron microscopy and for immunocytochemistry for DMP 1. Results Extrusion yielded both types of tertiary Dentine, which varied in aspect and related cells. DMP 1 was found in the mineralized matrix of all types of Dentine, presenting high affinity for collagen, but rare colloidal gold particles over preDentine. DMP 1 was evident in the supranuclear region and inside the nucleus of some odontoblast-like cells. Conclusion The observed association between DMP 1 and collagen seem to be essential for reactionary and Reparative Dentine formation.
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ultrastructural and immunocytochemical analyses of osteopontin in reactionary and Reparative Dentine formed after extrusion of upper rat incisors
Journal of Anatomy, 2007Co-Authors: Marcio Cajazeira Aguiar, Victor E AranachavezAbstract:Reactionary Dentine and Reparative Dentine are two strategies used by the Dentine-pulp complex to respond to injury. The reactionary Dentine is secreted by original odontoblasts, while the Reparative Dentine is formed by odontoblast-like cells. Osteopontin (OPN) is a non-collagenous protein usually present in the repair of mineralized tissues. It is likely to be present in newly formed Dentine but there are no studies attempting to detect it in reactionary and Reparative Dentine. The aim of the present study was to examine the ultrastructural characteristics, as well as the presence and distribution of OPN in reactionary and Reparative Dentine by provoking extrusion of the rat incisor. The right upper incisors of 3-month-old male rats were extruded 3 mm and then repositioned into their original sockets. At 3, 7, 10, 15, 20, 30 and 60 days after surgery, the incisors were fixed in glutaraldehyde-formaldehyde and then processed for scanning and transmission electron microscopy and for immunocytochemistry for OPN. After extrusive trauma, the Dentine-pulp interface showed the presence of reactionary and Reparative Dentine, which varied in aspect, thickness and related cells. OPN was not detected in the physiological and reactionary Dentine, while it was strongly immunoreactive in the matrix that surrounded the entrapped cells of Reparative Dentine. In addition, original odontoblasts subjacent to the physiological Dentine contained OPN in their Golgi region. The present findings showed that Reparative Dentine shares some structural characteristics with primary bone, especially in relation to its OPN content. The odontoblast-like cells resemble osteoblasts rather than odontoblasts.