Anti-inflammatory cerium-containing nano-scaled mesoporous bioactive glass for promoting regenerative capability of dental pulp cells.

AIMS: This study aimed to investigate the anti-inflammatory and odontoblastic effects of cerium-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) on dental pulp cells as novel pulp-capping agents. METHODOLOGY: Ce-MBGNs were synthesized using a post-impregnation strategy based on the antioxidant properties of Ce ions and proposed the first use of Ce-MBGNs for pulp-capping application. The biocompatibility of Ce-MBGNs was analysed using the CCK-8 assay and apoptosis detection. Additionally, the reactive oxygen species (ROS) scavenging ability of Ce-MBGNs was measured using the 2,7-Dichlorofuorescin Diacetate (DCFH-DA) probe. The anti-inflammatory effect of Ce-MBGNs on THP-1 cells was further investigated using flow cytometry and quantitative real-time polymerase chain reaction (RT-qPCR). Moreover, the effect of Ce-MBGNs on the odontoblastic differentiation of the dental pulp cells (DPCs) was assessed by combined scratch assays, RT-qPCR, western blotting, immunocytochemistry, Alizarin Red S staining and tissue-nonspecific alkaline phosphatase staining. Analytically, the secretions of tumour necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were detected with enzyme-linked immunosorbent assay (ELISA). RESULTS: Ce-MBGNs were confirmed to effectively scavenge ROS in THP-1-derived macrophages and DPCs. Flow cytometry and RT-qPCR assays revealed that Ce-MBGNs significantly inhibited the M1 polarization of macrophages (Mφ). Furthermore, the protein levels of TNF-α and IL-1ß were downregulated in THP-1-derived macrophages after stimulation with Ce-MBGNs. With a step-forward virtue of promoting the odontoblastic differentiation of DPCs, we further confirmed that Ce-MBGNs could regulate the formation of a conductive immune microenvironment with respect to tissue repair in DPCs, which was mediated by macrophages. CONCLUSIONS: Ce-MBGNs protected cells from self-produced oxidative damage and exhibited excellent immunomodulatory and odontoblastic differentiation effects on DPCs. As a pulp-capping agent, this novel biomaterial can exert anti-inflammatory effects and promote restorative dentine regeneration in clinical treatment. We believe that this study will stimulate further correlative research on the development of advanced pulp-capping agents.

Regenerative potential of a novel aloe vera modified tricalcium silicate cement as a pulp capping material: An animal study.

This study compared the histologic response of a pulp capping material Matreva MTA modified with different concentrations of aloe vera (AV) solutions to Biodentine cement. Ninety dogs' teeth were included and categorized according to the capping material into five groups (18 teeth each); Group I (Biodentine), group II (Matreva MTA), group III (Matreva MTA 10% AV), group IV (Matreva MTA 20% AV) and group V (Matreva MTA 30% AV). The histopathological findings were recorded at 2, 4, and 8 weeks. Matreva MTA and Biodentine groups showed the highest inflammatory cell count compared to the AV-modified Matreva MTA groups at 2- and 4-week intervals (p>0.05). Moreover, the AV-modified Matreva MTA and Biodentine groups showed higher dentin bridge thickness compared to unmodified Matreva MTA at different follow-up periods (p<0.05). AV can significantly enhance the in vivo bioactivity of Matreva MTA, inducing mild inflammation and good dentine bridge formation comparable to Biodentine.

Impact of corticosteroid administration on the response of exposed dental pulp to capping with bioactive cements-experimental study on mongrel dogs.

BACKGROUND: Corticosteroids are commonly used as a treatment for a variety of pathological conditions, however, systemic corticosteroid administration has adverse effects including impaired immune response and wound healing. Such complications may affect pulp healing after direct pulp capping. The current study evaluated the influence of corticosteroids on the healing ability of exposed dogs' dental pulps after direct pulp capping (DPC) with bioactive materials. METHODS: Ten healthy male dogs were assigned randomly into two groups, 5 dogs each: group I represent the control group which did not receive any medication, and group II was given corticosteroid for 45 days before DPC and till the dogs were euthanized (n = 75 teeth for each group). Following mechanical exposure, the pulps were randomly capped with either Ca(OH)2, MTA, or Biodentine. The pulpal tissues' reaction to the capping materials was evaluated 65 days postoperatively according to the following parameters: calcific bridge formation, pulpal inflammation, pulp necrosis, and bacterial infiltration. RESULTS: The corticosteroid-treated group revealed no significant difference compared to the control group concerning the pulp healing response (P > 0.05). Both Biodentine and MTA-treated specimens revealed significant differences with Ca(OH)2-treated specimens (P < 0.05) which displayed a superior positive effect of both MTA and Biodentine to Ca(OH)2 regarding all the parameters. CONCLUSIONS: Direct pulp capping technique whenever indicated in subjects treated with corticosteroid immunosuppressive drugs like prednisone performed well in aseptic conditions especially when capped with bioactive materials.

Inflammatory response and odontogenic differentiation of inflamed dental pulp treated with different pulp capping materials: An in vivo study.

AIM: Previous studies have evaluated the pulpal responses to calcium silicate cements (CSCs) on normal dental pulp, but investigations on the effects of CSCs on inflamed pulp are limited. This study aimed to test the inflammatory response and odontogenic differentiation of inflamed rat dental pulp after direct pulp capping with CSCs. METHODOLOGY: Wistar rat molars pulps were exposed for 48 h to induce inflammation and then capped with ProRoot MTA (Dentsply), Biodentine (Septodont), RetroMTA (Bio MTA) and Dycal (Dentsply Caulk). The degree of pulpal inflammation and hard tissue formation was evaluated by histological analysis. Immunofluorescence staining for interleukin (IL)-6, osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) was also performed. RESULTS: After 4 weeks, complete recovery from inflammation was evident in 22%, 37.5%, 10% and none of the ProRoot MTA, Biodentine, RetroMTA and Dycal samples, respectively. Heavy hard tissue deposition as a continuous hard tissue bridge was observed in 77.8%, 75%, 70% and 60% of the ProRoot MTA, Biodentine, RetroMTA and Dycal samples, respectively. IL-6, OCN and RUNX2 were detected in all materials, mainly adjacent to areas of inflammation and reparative dentine formation. At one, two and 4 weeks, significant differences were not observed between the inflammation and hard tissue formation scores of the four material groups (p > .05). CONCLUSIONS: In this study, pulpal inflammation was still present in most specimens at 4 weeks after pulp capping and a significant number of samples showed incomplete and discontinuous dentine bridge formation. The results of this study suggest that initial inflammatory conditions of the pulp may risk the prognosis of teeth treated with CSCs.

Comparative Evaluation of Ozonoid Olive Oil and Calcium Hydroxide as an Indirect Pulp Capping Agent in Primary Mandibular Second Molar: A Randomized Controlled Trial.

AIM: The aim of this study was to evaluate clinical and radiographical success of ozonoid olive oil as an indirect pulp capping (IPC) agent in primary mandibular second molar when compared to calcium hydroxide and to evaluate the antimicrobial efficacy of ozonoid olive oil on Streptococcus mutans and Lactobacilli. MATERIALS AND METHODS: A split-mouth randomized controlled trial was conducted on 30 primary mandibular second molars in 15 children of age 5-9 years with deep dentinal carious lesion. Teeth were randomly allocated to two groups of 15 each. After achieving local anesthesia and rubber dam isolation, an IPC procedure was performed using ozonoid olive oil in group I and calcium hydroxide in group II. Teeth were evaluated clinically and radiographically at 6 and 12 months of follow-up for success or failure of IPC. The bacterial counts of S. mutans and Lactobacilli were measured before and after application of ozonoid olive oil for 60 seconds on dentinal tissue in group I and recorded as colony-forming units per mL (CFU/mL). RESULTS: There were no statistically significant differences found between the materials used for IPC (p >0.05). About 93.33% and 100% clinical and radiographical success rates were seen in group I and group II, respectively. Statistically significant differences were observed for bacterial reduction after the application of ozonoid olive oil (p <0.05) for both the microorganisms. CONCLUSION: The results of this study showed that the success of IPC is independent of capping material. Ozonoid olive oil, an antimicrobial agent, can also be used for IPC. The success of the IPC procedure depends on a reduction in the bacterial count and sealing of the tooth with hermetic restoration. More clinical studies with a larger sample size and longer follow-up duration are required for understanding the efficacy of this material. CLINICAL SIGNIFICANCE: Ozonoid olive oil can be used as an IPC agent in primary molars and also for a bacterial reduction in dentinal caries.

Are resin-containing pulp capping materials as reliable as traditional ones in terms of local and systemic biological effects?

The aim of this study was to compare the local and systemic effects of current pulp capping materials containing resin with those of traditional materials in an animal study. A total of 48 rats were used: a control group (n=12) (sub-control and negative control), a resin-containing group (n=18) (Calcimol LC, Theracal LC, Activa-BioActive Base/Liner), and a traditional group (n=18) (Biodentine, ProRoot MTA, Dycal). The materials which had been placed in polyethylene tubes were implanted in subcutaneous pockets. The rats were sacrificed at 1, 2, or 4 weeks. Evaluations were made of subcutaneous connective tissue, the left kidney, liver, and blood samples. Of all the study groups, MTA demonstrated biocompatibility at a level close to that of the control groups. Inflammation was observed to be more severe in resin-containing materials, but Activa Base/Liner showed a more successful local and systemic tissue response.

Multifunctional Ca-Zn-Si-based micro-nano spheres with anti-infective, anti-inflammatory, and dentin regenerative properties for pulp capping application.

While pulp capping using a variety of materials has been applied clinically to preserve the health and vitality of the dental pulp and induce dentin repair no material meets all the anti-infection, anti-inflammation, and promoting pulp tissue regeneration criteria. Micro-nano materials of bioactive glasses (BG) with the biocompatibility and osteogenesis-promoting properties were developed for this study using Zn-doped bioactive glass (BGz) micro-nano spheres for dental pulp capping to control infection and inflammation and promote tissue regeneration. Of three key findings, the co-culture of Porphyromonas gingivalis showed that the BGz had an excellent antibacterial effect, and after being stimulated with BGz in vitro, macrophages showed a significant decrease of pro-inflammatory M1 markers compared with the undoped BG group. It is also noted that the conditioned medium derived from BGz-stimulated macrophages could significantly promote mineralized dentin formation of dental pulp cells (DPCs). In rats, acute pulp restoration experiments proved that BGz used as a pulp capping agent had excellent dentin regenerative properties. This work may provide a novel strategy to promote osteo/dentinogenic differentiation through regulating early inflammation, with potential applications in pulp capping.

The effect of mineral trioxide aggregate on dental pulp healing in the infected pulp by direct pulp capping.

This study aimed to clarify the effect of mineral trioxide aggregate (MTA) on pulp healing in the infected pulp by direct pulp capping (DPC). Thirty-six male ICR mice were divided into infected and uninfected groups. The pulp tissue was exposed to the oral flora for 24 h after pulp exposure in the infected group, or not exposed in the uninfected group, followed by sealing with MTA, calcium hydroxide cement (CH), or no DPC. Pulpal healing process was analyzed by hematoxylin-eosin staining and immunohistochemistry for nestin and Ki67. The active cell proliferation occurred on 1 week in the both MTA and CH groups, followed by the differentiation of odontoblast-like cells on 2 weeks in the MTA group, whereas their differentiation were not facilitated in the CH group. MTA is suggested to be a useful material for DPC with the infected and uninfected pulp tissue.

Graphene oxide-coated porous titanium for pulp sealing: an antibacterial and dentino-inductive restorative material.

Pulp treatment techniques such as pulp capping, pulpotomy and pulp regeneration are all based on the principle of preserving vital pulp. However, specific dental restorative materials that can simultaneously protect pulp vitality and repair occlusal morphology have not been developed thus far. Traditional pulp capping materials cannot be used as dental restorative materials due to their long-term solubility and poor mechanical behavior. Titanium (Ti) is used extensively in dentistry and is regarded as a promising material for pulp sealing because of its favorable biocompatibility, processability and mechanical properties. Originally, we proposed the concept of "odontointegration", which represents direct dentin-like mineralization contact between pulp and the surface of the pulp sealing material; herein, we report the fabrication of a novel antibacterial and dentino-inductive material via micro-arc oxidation (MAO), incorporating self-assembled graphene oxide (GO) for Ti surface modification. The hierarchical micro/nanoporous structure of the MAO coating provides a suitable microenvironment for odontogenic differentiation of human dental pulp stem cells, and GO loading contributes to antibacterial activity. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy and Raman spectroscopy were employed for structure and elemental analysis. In vitro studies, including cell adhesion, Live/Dead and CCK-8 assays, alkaline phosphatase activity and calcium deposition assay, real-time polymerase chain reaction, western blot analysis and immunofluorescence staining were used to examine cell adhesion, viability, proliferation, mineralization, and odontogenic differentiation ability. Antibacterial properties against Streptococcus mutans were analyzed by SEM, spread plate, Live/Dead and Alamar blue tests. The Ti-MAO-1.0 mg mL-1 GO group exhibited excellent cell adhesion, odontoblast differentiation, mineralization, and antibacterial ability, which are beneficial to odontointegration.

Development of self-adhesive pulp-capping agents containing a novel hydrophilic and highly polymerizable acrylamide monomer.

Several studies have shown the clinical success of hydraulic calcium-silicate cements (hCSCs) for direct and indirect pulp capping and root repair. However, hCSCs have various drawbacks, including long setting time, poor mechanical properties, low bond strength to dentin, and relatively poor handling characteristics. To overcome these limitations, a light-curable, resin-based hCSC (Theracal LC, Bisco) was commercially introduced; however, it did not exhibit much improvement in bond strength. We developed a light-curable self-adhesive pulp-capping material that contains the novel acrylamide monomer N,N'-{[(2-acrylamido-2-[(3-acrylamidopropoxy)methyl]propane-1,3-diyl)bis(oxy)]bis(propane-1,3-diyl)}diacrylamide (FAM-401) and the functional monomer 4-methacryloxyethyl trimellitate anhydride (4-MET). Two experimental resin-based hCSCs containing different calcium sources (portlandite: Exp_Pl; tricalcium silicate cement: Exp_TCS) were prepared, and the commercial hCSCs Theracal LC and resin-free hCSC Biodentine served as controls. The performance of each cement was evaluated based on parameters relevant for vital pulp therapy, such as curing degree on a wet surface, mechanical strength, as determined using a three-point bending test, shear bond strength to dentin, cytotoxicity, as determined using an MTT assay, and the amount of calcium released, as determined using inductively coupled plasma atomic emission spectrometry. Both experimental cements cured on wet surfaces and showed relatively low cytotoxicity. Furthermore, their flexural and shear bond strength to dentin were significantly higher than those of the commercial references. High calcium release was observed for both Exp_Pl and Biodentine. Thus, Exp_Pl as a new self-adhesive pulp-capping agent performed better than the commercial resin-based pulp-capping agent in terms of mechanical strength, bond strength, and calcium release.

Melatonin as an Agent for Direct Pulp-Capping Treatment.

Melatonin plays an essential role in the regulation of bone growth. The actions that melatonin exerts on odontoblasts may be similar to its action on osteoblasts. This research aimed to evaluate the pulp response to melatonin used for direct pulp capping to evaluate the antioxidant effect of melatonin administered orally and its influence on dental pulp. Direct pulp capping was performed on the upper molars of Sprague Dawley rats using melatonin or Mineral Trioxide Aggregate (MTA). The study groups were: MTA; Melatonin; MTA + Melatonin administered orally; and Melatonin + Melatonin administered orally. In the latter two groups, the animals drank water dosed with melatonin ad libitum (10 mg/100 mL). After 30 days, the animals were sacrificed, and 5 ml of blood, the kidneys, and the liver were extracted in order to evaluate oxidative stress using thiobarbituric acid reactive substances testing (TBARS). Fragments of the maxilla containing the study molars were prepared for histological evaluation. The degree of pulp inflammation and pulp necrosis, the presence of reparative dentin and dentin bridging the pulp chamber, the presence and regularity of the odontoblastic layer, and the presence of pulp fibrosis were evaluated. No significant differences were found between the four study groups for any of the studied histological variables. The oral administration of melatonin did not modify the local effects of MTA or melatonin on dental pulp, or reduce basal-level oxidative stress. The effect of melatonin on pulp is similar to that of MTA and may be used as an agent for direct pulp capping.

Evaluation of dentinogenesis inducer biomaterials: an in vivo study.

When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. OBJECTIVE: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. METHODOLOGY: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). RESULTS: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. CONCLUSIONS: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications.

Evaluation of dentinogenesis inducer biomaterials: an in vivo study

Abstract When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. Objective: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. Methodology: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). Results: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. Conclusions: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications

Pulpotomy with curcumin: Histological comparison with mineral trioxide aggregate in rats.

CONTEXT: It is important to develop new therapeutic materials that have requisite clinical actions, are safe and economical. AIMS: This study aims to histologically evaluate curcumin, an extract of turmeric (Curcuma longa) as a pulpotomy agent in rat molars and to compare it to mineral trioxide aggregate (MTA). SETTINGS AND DESIGN: Animal study. SUBJECTS AND METHODS: Twelve Wistar-Albino rats were randomly divided into two groups of 6 each. Pulpotomies were performed on caries free maxillary first and second molars on both sides of the arch, with MTA and curcumin (24 teeth each), respectively. Access cavities were sealed with resin-modified glass ionomer cement. Postoperative histological evaluation of pulpotomized teeth in both groups was done at 7, 14, and 30 days under a light microscope (×10). STATISTICAL ANALYSIS USED: Data were evaluated with Freidman's test and Mann-Whitney test at 0.05 level. RESULTS: (a) There was a gradual reduction in inflammatory cell response in both groups across time periods tested (MTA P = 0.074, curcumin P = 0.039). (b) The overall architecture of pulp was maintained better in the curcumin group across all time periods tested (P = 0.368). (c) Dentinal bridge formation was consistently seen across time periods tested in MTA group (P = 0.9094) and was feeble in curcumin group (P = 0.9094) across time periods tested. CONCLUSIONS: Curcumin has been shown to have wound healing properties. It has the potential to be developed into a predictable and cost-effective vital pulp therapy medicament.

Effects of two fast-setting pulp-capping materials on cell viability and osteogenic differentiation in human dental pulp stem cells: An in vitro study.

OBJECTIVE: The purpose of this study was to compare the effects of two fast-setting pulp-capping materials, Biodentine (BD) and iRoot Fast Set (FS) root repair material, on the attachment, viability, migration, and differentiation of human dental pulp stem cells (hDPSCs). METHODS: A comparative study was conducted between BD and FS material disks. Scanning electron microscope (SEM) images were used to observe the attachment of hDPSCs on the disks. A live/dead assay was used to assess the cell viability. Transwell assay was performed to study cell migration. Cell differentiation was determined by quantitative real-time polymerase chain reaction (qRT-PCR) for the analysis of osteogenic differentiation gene expression: alkaline phosphatase (ALP), collagen type I (COL1) and osteocalcin (OCN). RESULTS: SEM images indicated that hDPSCs showed a well-spreading morphology on both BD and FS disks. FS significantly increased the proliferation and migration of hDPSCs on day 7 (P＜0.05). Neither BD nor FS promoted the expression of osteogenic genes during the observation period. CONCLUSIONS: BD and FS both were beneficial to hDPSC attachment, and they had similar effects on cell osteogenic differentiation, whereas FS performed better than BD on hDPSCs proliferation and migration.

In vitro and in vivo effects of a novel bioactive glass-based cement used as a direct pulp capping agent.

Direct pulp capping is an important procedure for preserving pulp viability. The pulp capping agent must possess several properties, including usability, biocompatibility, and the ability to induce reparative dentin formation. In this study, a novel bioactive glass-based cement was examined to determine whether the cement has the necessary properties to act as a direct pulp capping agent. Physicochemical properties of the bioactive glass-based cement and in vitro effects of the cement on odontoblast-like cells, as well as in vivo effects on the exposed dental pulp, were analyzed. The cement immersed in water stabilized at pH10, and hydroxyapatite-like precipitation was induced on the surface of the cement in simulate body fluid. There were no cytotoxic effects on the viability, alkaline phosphatase activity, or calcium deposition ability of odontoblast-like cells. In the in vivo rat study of an exposed dental pulp model, the cement induced a sufficient level of reparative dentin formation by odontoblast-like cells expressing odontoblastic markers at the exposed area of the dental pulp. These results suggest that the newly developed bioactive glass-based cement provides favorable biocompatibility with the dental pulp and may be useful as a direct pulp capping agent. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 161-168, 2019.

Biocompatibility of mineral trioxide aggregate flow and biodentine.

AIM: To evaluate the influence of powder-to-gel ratio (0.19 g powder to 50 µL of gel, thick MTA Flow, and 0.06 g powder to 50 µL of gel, fluid MTA Flow) on biocompatibility of MTA Flow (Ultradent Products Inc., South Jordan, UT, USA, lot: 2015122901) and compare it with Biodentine (Septodont Inc., Saint-Maur-des-Fossés, France, lot: B18542A). METHODOLOGY: The materials were manipulated and inserted into polyethylene tubes for implantation in twenty rats. After 7, 15, 30 and 60 days, the specimens were removed and embedded in paraffin. Haematoxylin and eosin sections were used to count the number of inflammatory cells (IC) and fibroblasts mm-2 (Fb). In the Masson's trichrome-stained sections, the fibrous capsule thickness was measured; picrosirius red-stained sections were used for birefringent collagen quantification. The data were submitted to two-way ANOVA and Tukey test (P ≤ 0.05). RESULTS: A significantly lower number of IC and consequently higher number of Fb were observed in the capsules adjacent to thick MTA Flow at all periods, in comparison with other materials (P ≤ 0.05). At 60 days, the quantity of birefringent collagen was significantly greater in the tissue in contact with thick MTA Flow, when compared with fluid MTA Flow and Biodentine. CONCLUSIONS: Although thick MTA Flow induced a less intense inflammatory response, all evaluated materials are biocompatible because they allowed regression of this process after 60 days.

Characterization of the biological effect of BiodentineTM on primary dental pulp stem cells.

BACKGROUND: Biodentine™ is relatively a new tricalcium silicate cement that has gained great attention of the researchers due to its biological potential in comparison with other materials. The aim of this study was to investigate the optimum concentrations of Biodentine in relation to its stimulatory or inhibitory effect on proliferation, migration and adhesion of stem cells of human exfoliated deciduous teeth (SHED). The cell cultures of SHED were treated with Biodentine™ extract at four different concentrations; 20mg/ml, 2mg/ml, 0.2mg/ml and 0.02mg/ml. Cells cultured without Biodentine™ were kept as a blank control. The proliferation potential of SHED cells was evaluated by MTT viability analysis for 6 days. Migration potential was investigated by wound healing and transwell migration assays. The growth, survival and communication potential of these cells was determined by Adhesion assay. RESULTS: A significant increase was observed in the proliferation and migration of SHED at (2mg/ml, 0.2mg/ml and 0.02mg/ml) while higher concentration of Biodentine™ (20mg/ml) exhibited cytotoxic effect on the cells. However, three tested Biodentine™ concentrations were similar in effect (non-significant) to adhesion ability of cells when compared with blank control. CONCLUSION: Our findings suggest that lower concentrations of Biodentine™ can be considered as the optimum concentrations to enhance the stimulatory effect of Biodentine on SHED.

Tricalcium Silicate Capping Materials Modulate Pulp Healing and Inflammatory Activity In Vitro.

INTRODUCTION: On stimulation by lipoteichoic acid or by a physical injury, fibroblasts have been shown to play a major role in the initiation of the pulp inflammatory reaction and healing through secretion of complement proteins and growth factors. The application of direct pulp-capping materials on these cells may interfere with the inflammatory and the healing processes within the pulp's inextensible environment. This work was designed to study in vitro the effects of silicate-based materials on pulp fibroblast modulation of the initial steps of pulp inflammation and healing. METHODS: The effects of Biodentine, TheraCal, and Xeno III eluates were studied on lipoteichoic acid-stimulated and physically injured fibroblasts. Cytokine secretion (interleukin 6, vascular endothelial growth factor, fibroblast growth factor-2, and transforming growth factor-ß1) was quantified by enzyme-linked immunosorbent assay. Inflammatory THP-1 adhesion to endothelial cells and their migration and activation were studied in vitro. Human pulp fibroblast proliferation was investigated with the MTT test, and their migration to the injury site was studied with the scratch healing assay. RESULTS: Interleukin 6 and vascular endothelial growth factor secretion increased with all materials but to a lesser extent with Biodentine. Fibroblast growth factor-2 and transforming growth factor-ß1 secretion was significantly higher with Biodentine than with all other materials. THP-1 cell adhesion to endothelial cells and their activation were reduced by Biodentine and TheraCal. However, their migration decreased only with Biodentine. Fibroblast proliferation significantly increased with Biodentine but significantly decreased with Xeno III after day 6. Finally, only Biodentine induced fibroblast migration to the injury site in the scratch assay. CONCLUSIONS: These results confirm that pulp-capping materials affect the early steps of pulp inflammation and healing. They show that Biodentine had the highest pulp healing and anti-inflammatory potential when compared with the resin-containing materials. This highlights the interest of the material choice for direct pulp-capping.

Anti-inflammatory and Mineralization Effects of ProRoot MTA and Endocem MTA in Studies of Human and Rat Dental Pulps In Vitro and In Vivo.

INTRODUCTION: Few studies have reported direct pulp capping in inflamed pulp conditions. The purpose of this study was to investigate the in vitro and in vivo responses of dental pulp during direct pulp capping using various pulp capping materials in inflamed conditions. METHODS: Human dental pulp cells were treated with lipopolysaccharide (LPS) and cultured with Dycal (Dentsply Caulk, Milford, DE), ProRoot MTA (Dentsply Maillefer, Ballaigues, Switzerland), and Endocem MTA (Maruchi, Wonju, South Korea). The expressions of interleukin (IL)-1ß, IL-6, dentin matrix protein 1, and dentin sialophosphoprotein were analyzed through real-time polymerase chain reaction. The maxillary molars of Sprague-Dawley rats were exposed for 2 days. The exposed pulps were capped with Dycal, ProRoot MTA, and Endocem MTA and sealed with resin-modified glass ionomer followed by histologic and immunohistochemical analyses. RESULTS: The expression of IL-1ß and IL-6 was increased with LPS and decreased by Dycal, ProRoot MTA, and Endocem MTA. Dentin matrix protein 1 and dentin sialophosphoprotein levels were decreased with LPS and increased after treatment with pulp capping materials.In the in vivo study, inflammation associated with Dycal was higher than that associated with ProRoot MTA and Endocem MTA at week 1, without any significant difference between the 2. At 4 weeks, inflammation was decreased, and mineralization was increased compared with week 1 in all 3 of the materials. At week 1, IL-6 immunoreactivity was strongly expressed. Dycal exhibited stronger immunoreactivity than ProRoot MTA and Endocem MTA. However, the immunoreactivity was decreased in all groups at week 4. CONCLUSIONS: Successful direct pulp capping requires more effective pulp capping materials for the treatment of inflamed pulps.