The effect of four materials on direct pulp capping: An animal study

Impact of different capping materials extracts on proliferation and osteogenic differentiation of cultured human dental pulp stem cells

This study aimed to evaluate the effects of four bioactive capping material extracts on the proliferation and osteogenic differentiation of human dental pulp stem cells. Four capping material extracts were evaluated in this study [Harvard MTA (calcium silicate), Retro MTA (calcium zirconia complex material), Activa Bioactive Base/Liner (bioactive glass-based material) and an experimental MCP-based pulp capping material). The materials prepared according to their manufacturers' instructions in the form of discs. Each material disc was placed into one insert of a 6-well plate and covered with Dulbecco's Modified Eagle Medium to produce extracts at 1:1 ratio. Human dental pulp stem cells represent the negative control group, cells cultured in osteogenic media represent the positive control group, while cells cultured on the tested extracts represent the test groups. Each specimen was assessed in triplicate by three independent assays. The proliferation of stem cells was evaluated via MTT assay and cell viability was determined by measuring optical density. Osteogenic differentiation was assessed via the alizarin red stain test by measuring the H-score and calcium concentration. The proliferation and osteogenic differentiation data were analyzed using one-way ANOVA followed by Tukey's post hoc multiple comparison test (p ≤ 0.05). Regarding MTT assay results, osteogenic media was significantly greater than calcium zirconia complex and MCP-based material. In comparison with negative control and calcium zirconia complexes, calcium silicate significantly increased the optic density. Alizarin red staining revealed significantly low H-scores and calcium concentrations in the four tested capping materials in comparison with control group. The calcium concentration of calcium silicate material was significantly greater than the remaining tested materials.Calcium silicate-based materials seem to have the most reliable performance concerning the proliferation and osteogenic differentiation of human dental pulp stem cells. Newly introduced resin-based materials have shown acceptable results but need further investigation. The present study had a few limitations; mainly the need to perform more laboratory evaluations and in vivo studies.

Diffusion of Silver Diamine Fluoride Solution in Dentine: An In Vitro Study

OBJECTIVES

The aim of this research was to assess the diffusion dynamics of silver and fluoride ions after 38% silver diamine fluoride (SDF) solution application on dentine of varying thicknesses over 24 weeks.

METHODS

Bovine dentine discs of 5.5 mm in diameter were prepared and separated into 3 groups with thicknesses of 0.5 mm (group 1), 1.0 mm (group 2), and 1.5 mm (group 3). The diameter and number of dentinal tubules of discs were assessed. Each disc received a topical application of 0.05 mL 38% SDF solution. The deionised water in the tube was collected weekly for 24 weeks. The silver and the fluoride ion concentrations in the collected deionised water were determined. Generalised estimating equations was used to explore the potential effects of the key factors on the silver/fluoride diffusion.

RESULTS

The amount of silver and fluoride ion diffusion through dentine almost levelled off after 4 weeks and showed a decline trend over 24 weeks. The mean (SD) 24-week cumulative ion diffusion through dentine in groups 1, 2, and 3 was as follows: 20 (4) μg, 10 (2) μg, and 5 (1) μg for silver (P < .05) and 18 (2) μg, 13 (2) μg, and 7 (1) μg for fluoride (P < .05), respectively.

CONCLUSIONS

Silver and fluoride ion diffusion through dentine showed a decline trend over 24 weeks. The diameter and the number of dentinal tubules on dentine with different thicknesses affects the ion diffusion dynamics. This study provides indications on the pattern of silver/fluoride ions diffusion through dentine to pulp after 38% SDF application. An increased amount of silver/fluoride diffuses through dentine into the pulp with decreased remaining dentine thickness.

Histological and radiographic assessment of the regenerative potential of sodium hexametaphosphate (SHMP) as a novel direct pulp capping material in an animal model

BACKGROUND

This study aimed to assess the histological and radiographic effects of sodium hexametaphosphate (SHMP) as a direct pulp capping (DPC) agent in immature permanent dog premolars.

METHODS

A split-mouth design was employed with three healthy 4-month-old Mongrel dogs, each having 36 premolars. The premolars were randomly assigned to either SHMP or MTA. The specimens were stained with hematoxylin and eosin (H&E) and Masson's trichrome, and histologically examined three months after the animals were sacrificed. To assess root maturity, radiographic changes in root length (RL), root surface area (RSA), and apical foramen width (AFW) were measured at baseline and after 3 months. Quantitative data were analyzed using the paired-sample t-test, while the qualitative data based on Stanley's histological scoring system were tested using the Monte Carlo exact test. The level of significance was set at 5%.

RESULTS

Histological findings showed no significant differences between the two groups, except for the average thickness of the predentin and odontoblastic layers, which was significantly higher in the SHMP specimens (P < 0.0001). The frequencies of fully calcified dentin bridges and regularly arranged dentinal tubules were significantly higher in the SHMP specimens (P < 0.05). Both materials showed comparable radiographic measurements (P > 0.05), except for the change in RL, which was significantly longer in the SHMP group (P < 0.05).

CONCLUSIONS

There were no significant differences between SHMP and MTA in some respects. Histological evaluation showed that SHMP provided better bioinductive and biocompatible properties compared to MTA. Radiographically, both materials showed comparable root maturogenesis outcomes, except for the significant increase in RL in the SHMP group. SHMP may be a suitable alternative material for DPC in the treatment of immature permanent teeth.

Exploring vital pulp Therapies: A bibliometric analysis of the most cited articles

Aim

The aim of this study was to identify and analyze the most cited articles on vital pulp therapies.

Methodology

Bibliographical data related to the abstract, citations, keywords, and other relevant information was extracted using different combinations of keywords. Further evaluation and visualization of the selected data were performed with the help of various tools, including MS Excel, Microsoft Word, Google open refine, BibExcel, and VOS viewer. An initial search revealed 91 documents, of which 40 were chosen for further analysis. We used the Kolmogorov-Smirnov test and Spearman correlation coefficient test, and our adopted significance level was p < 0.05.

Results

In total, the articles received 1,905 citations, with six of them receiving at least 100 citations. Among the top 40 articles, the United States of America (10 articles) and Ireland (6 articles) were the countries with the highest number of cited articles. The journals "Journal of Endodontics" (14 articles; 650 citations) and "International Endodontic Journal" (13 articles; 577 citations) published most of the articles among the 50 most cited ones. Duncan H. was the author with the highest number of works cited (11 articles; 339 citations). Of the articles, systematic reviews accounted for 32%, literature reviews for 14%, in vitro experimental studies for 12%, clinical trials for 8%. Among the biomaterials used in vital pulp therapies, mineral trioxide aggregate (MTA) was discussed in 37 articles (74%), followed by calcium hydroxide, mentioned in 30 studies (60%). Interestingly, the publication year did not demonstrate a significant impact on citation count.

Conclusion

The present study provided a detailed list of the top 50 most cited and classic articles on vital pulp therapies. This will help researchers, students, and clinicians in the field of endodontics with an impressive source of information.

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.

Nano eggshell-based slurry as a direct pulp-capping material: In vitro characterization and histopathological assessment in an experimental animal model

AIM

Pulp vitality is essential for tooth integrity. Following pulp exposure, choosing a suitable pulp-capping material is crucial to maintain pulp vitality. However, the reparative dentine bridge created by calcium hydroxide (Ca(OH)2 ) is generally porous and incomplete. The aim of the current study is to assess the in vitro and in vivo bioactivities of nano eggshell-based slurry (NES), using NES as a direct pulp-capping material, compared with Ca(OH)2 in rabbit animal model.

METHODOLOGY

Nano eggshell powder (NE) was characterized for particle morphology, chemical composition and ion release. In vitro bioactivity was tested by immersion in simulated body fluid (SBF) for 7 days. For histopathological evaluation, 36 adult New Zealand rabbits (72 pulp exposures) were divided into nine groups (n = 8) according to the pulp-capping material (NES, Ca(OH)2 and no capping as negative control group) and the animals were sacrificed after 7, 14 or 28 days. The pulps of the two lower central incisors were exposed and then directly capped by Ca(OH)2 or NES or left untreated. The cavities were then sealed with glass ionomer cement. Teeth were collected for histopathological evaluation using an optical microscope. Pulp haemorrhage, inflammation, fibrosis and calcific bridge formation were assessed. Results were statistically analysed using anova and Tukey's tests.

RESULTS

Nano eggshell particles were spherical with a 20 nm diameter and were composed mainly of calcite. Statistical analysis showed that there was a significant increase in the release of all investigated ions between days 1 and 28, except for copper. NES group showed a significantly higher release of all elements as compared to Ca(OH)2 . Environmental scanning electron microscope micrographs of NES incubated for 7 days in SBF showed the formation of HAp with a Ca/P ratio (1.686). For histopathological evaluation, the difference between groups was statistically significant. At day 28, 75% of the pulps of the Ca(OH)2 group showed mild calcific bridge in comparison with 100% moderate calcific bridge in the NES group. The NES group showed significantly less inflammation at days 7 and 28, and higher fibrosis at day 7 compared with Ca(OH)2 .

CONCLUSIONS

Nano eggshell-based slurry represents a promising novel direct pulp-capping material with favourable pulp tissue response.

Advanced materials and technologies for oral diseases

Oral disease, as a class of diseases with very high morbidity, brings great physical and mental damage to people worldwide. The increasing burden and strain on individuals and society make oral diseases an urgent global health problem. Since the treatment of almost all oral diseases relies on materials, the rapid development of advanced materials and technologies has also promoted innovations in the treatment methods and strategies of oral diseases. In this review, we systematically summarized the application strategies in advanced materials and technologies for oral diseases according to the etiology of the diseases and the comparison of new and old materials. Finally, the challenges and directions of future development for advanced materials and technologies in the treatment of oral diseases were refined. This review will guide the fundamental research and clinical translation of oral diseases for practitioners of oral medicine.

Biomimetic Approaches in Clinical Endodontics

In the last few decades, biomimetic concepts have been widely adopted in various biomedical fields, including clinical dentistry. Endodontics is an important sub-branch of dentistry which deals with the different conditions of pulp to prevent tooth loss. Traditionally, common procedures, namely pulp capping, root canal treatment, apexification, and apexigonesis, have been considered for the treatment of different pulp conditions using selected materials. However, clinically to regenerate dental pulp, tissue engineering has been advocated as a feasible approach. Currently, new trends are emerging in terms of regenerative endodontics which have led to the replacement of diseased and non-vital teeth into the functional and healthy dentine-pulp complex. Root- canal therapy is the standard management option when dental pulp is damaged irreversibly. This treatment modality involves soft-tissue removal and then filling that gap through the obturation technique with a synthetic material. The formation of tubular dentine and pulp-like tissue formation occurs when stem cells are transplanted into the root canal with an appropriate scaffold material. To sum up tissue engineering approach includes three components: (1) scaffold, (2) differentiation, growth, and factors, and (3) the recruitment of stem cells within the pulp or from the periapical region. The aim of this paper is to thoroughly review and discuss various pulp-regenerative approaches and materials used in regenerative endodontics which may highlight the current trends and future research prospects in this particular area.

Dentin Sialoprotein/Phosphophoryn (DSP/PP) as Bio-Inductive Materials for Direct Pulp Capping

Conventional direct pulp capping, such as calcium hydroxide (Ca(OH)₂) or silicate products, usually induces an inflammatory reaction to provoke pulp regeneration. Phosphophoryn (PP) and dentin sialoprotein (DSP), the two most abundant non-collagenous proteins in the dentin matrix, are responsible for dentin mineralization, pulp cell migration, and differentiation. Here we examined the PP and combined DSP/PP as bio-inductive pulp capping materials by in vitro and in vivo tests. Firstly, the effects of the PP dose on pulp cell migration and matrix protein expression were examined by an agarose bead test. Secondly, the role of recombinant DSP (recDSP) and recDSP/PP on stimulating DSP-PP transcript expression was examined by RT-PCR. DSPP mRNA was also knocked down by RNA interference (RNAi) to examine their functions on dentin matrix mineralization. Finally, we used ferret animal models to test PP and recDSP/PP acting as capping agents on in vivo pulp responses and reparative dentin formation. The result showed that intermediate-dose PP was the most effective to enhance cell migration and differentiation. RecDSP/PP strongly enhanced the DSP-PP transcript expression, while inhibition of DSPP mRNA expression by siRNAs partially or completely affected dental pulp cell mineralization. The in vivo results showed that intermediate-dose PP and recDSP/PP proteins induced less pulp inflammation and promoted reparative dentin formation. Contrarily, conventional calcium hydroxide induced severe pulp inflammation. With these findings, DSP and PP could serve as capping agents for pulp capping therapy.

Efficacy of Mineral Trioxide Aggregate and Photobiomodulation on Pulp Capping of Dogs’ Teeth

AIM: The present study assessed the effect of mineral trioxide aggregate (MTA) and photobiomodulation (PBM) on pulp capping of exposed pulp of dogs’ teeth. METHODS: Forty-eight teeth in three mongrel dogs were randomly divided into two major study groups; Group I where MTA was used as a pulp capping agent and Group II in which both MTA+PBM were used. The groups were equally subdivided according to the observation period following completion of pulp capping into Subgroup (A) 1 week, Subgroup (B) 2, and Subgroup (C) 16 weeks. The teeth were examined for histological inflammatory response as well as dentine bridge formation. RESULTS: With regard to inflammatory response at 1 week significantly, less intense inflammation was observed in MTA+PBM (Group II) compared to the MTA (Group I) for the same time period with no significant difference for between Group I and Group II for other time intervals. As for dentin bridge formation, PBM+MTA groups showed statistically significant thicker dentine bridge formation at 16 weeks than MTA alone group for the same time period with no significant difference for between Group I and Group II for other time intervals. CONCLUSIONS: Under the conditions of this study, PBM appeared to be a beneficial adjunct in dental pulp capping procedures in which MTA was the pulp capping material.

The effect of low-level laser on the quality of dentin barrier after capping with bioceramic material: A histomorphometric analysis

The study aims to investigate the quality of dentin barriers and pulp reaction to EndoSequence Root Repair Material (ERRM) combined with low-level laser application. In eight dogs, pulps were exposed via class V, half of the samples received low-level diode laser at 870 nm. Thereafter, cavities were capped with fast-set or regular-set ERRM. The specimens were processed for histomorphological and immunohistochemical examination after 2 weeks and 2 months. Dentin bridges were observed in all samples, and 87.5% were complete. The low-level laser group had significantly more reparative dentin area than the non-lased group (p < 0.05). The dentin bridges were found to have an unprecedented tubularity of 43%-89%. Tiny dentin island formation was observed within the material particles. Initial mild-to-moderate inflammatory reactions were observed, which subsided after 2 months. RUNX2 and osteocalcin staining were evident for all samples at both time intervals. Low-level laser combined with bioactive ERRM is effective in inducing reparative dentin formation.

Mineral-induced bubbling effect and biomineralization as strategies to create highly porous and bioactive scaffolds for dentin tissue engineering

The objective of the study was to assess the biological and mechanical characteristics of chitosan-based scaffolds enriched by mineral phases and biomineralized in simulated body fluid (SBF) as a possible biomaterial for dentin regeneration. Thus, porous chitosan scaffolds were prepared by the mineral-induced bubbling-effect technique and subjected to biomineralization to create biomimetic scaffolds for dentin tissue engineering. Suspensions containing calcium hydroxide, nanohydroxyapatite, or β-tricalcium phosphate were added to the chitosan (CH) solution and subjected to gradual freezing and freeze-drying to obtain CHCa, CHnHA, and CHβTCP porous scaffolds, respectively, by the bubbling effect. Then, scaffolds were incubated in SBF for 5 days at 37°C, under constant stirring, to promote calcium-phosphate (CaP) biomineralization. Scanning electron microscopy revealed increased pore size and porosity degree on mineral-containing scaffolds, with CHCa and CHnHA presenting as round, well-distributed, and with an interconnected pore network. Nevertheless, incubation in SBF disrupted the porous architecture, except for CHCa_SBF , leading to the deposition of CaP coverage, confirmed by Fourier Transform Infrared Spectroscopy analyses. All mineral-containing and SBF-treated formulations presented controlled degradation profiles and released calcium throughout 28 days. When human dental pulp cells (HDPCs) were seeded onto scaffold structures, the porous and interconnected architecture of CHCa, CHnHA, and CHCa_SBF allowed cells to infiltrate and spread throughout the scaffold structure, whereas in other formulations cells were dispersed or agglomerated. It was possible to determine a positive effect on cell proliferation and odontogenic differentiation for mineral-containing formulations, intensely improved by biomineralization. A significant increase in mineralized matrix deposition (by 8.4 to 18.9 times) was observed for CHCa_SBF , CHnHA_SBF , and CHβTCP_SBF in comparison with plain CH. The bioactive effect on odontoblastic marker expression (ALP activity and mineralized matrix) was also observed for HDPCs continuously cultivated with conditioned medium obtained from scaffolds. Therefore, biomineralization of chitosan scaffolds containing different mineral phases was responsible for increasing the capacity for mineralized matrix deposition by pulpal cells, with potential for use in dentin tissue engineering.

Development and Analysis of a Hydroxyapatite Supplemented Calcium Silicate Cement for Endodontic Treatment

Aim: To develop an endodontic cement using bovine bone-derived hydroxyapatite (BHA), Portland cement (PC), and a radiopacifier. Methods: BHA was manufactured from waste bovine bone and milled to form a powder. The cements were developed by the addition of BHA (10%/20%/30%/40% wt), 35% wt, zirconium oxide (radiopacifier) to Portland cement (PC). A 10% nanohydroxyapatite (NHA) cement containing PC and a radiopacifier, and a cement containing PC (PC65) and a radiopacifier were also manufactured as controls. The cements were characterised to evaluate their compressive strength, setting time, radiopacity, solubility, and pH. The biocompatibility was assessed using Saos-2 cells where ProRoot MTA acted as the control. Compressive strength, solubility and pH were evaluated over a 4-week curing period. Results: The compressive strength (CS) of all cements increased with the extended curing times, with a significant CS increase in all groups from day 1 to day 28. The BHA 10% exhibited significantly higher CS compared with the other cements at all time points investigated. The BHA 10% and 20% groups exhibited significantly longer setting times than BHA 30%, 40% and PC65. The addition of ZrO₂ in concentrations above 20% wt and Ta₂O₅ at 30% wt resulted in a radiopacity equal to, or exceeding that of, ProRoot MTA. The experimental cements exhibited relatively low cytotoxicity, solubility and an alkaline pH. Conclusions: The addition of 10% and 20% BHA to an experimental PC-based cement containing 35% ZrO₂ improved the material’s mechanical strength while enabling similar radiopacity and biocompatibility to ProRoot MTA. Although BHA is a cost-effective, biomimetic additive that can improve the properties of calcium silicate endodontic cements, further studies are now warranted to determine its clinical potential.

Update on Endodontic, Restorative, and Prosthodontic Therapy

Endodontic therapy is intended to preserve the function of mature teeth with irreversible pulpitis or pulp necrosis or to maintain the vitality of endodontically compromised immature teeth. Standard root canal therapy and vital pulp therapy are 2 mainstays of endodontic treatment. Recent knowledge has improved the outcomes of endodontic treatment with newer materials, such as mineral trioxide aggregate. Composite or prosthodontic crown restoration is also a critical key to success.

Effectiveness of Direct Pulp Capping Bioactive Materials in Dentin Regeneration: A Systematic Review

Background: Regenerative endodontics aims to restore normal pulp function in necrotic and infected teeth, restoring protective functions, such as innate pulp immunity, pulp repair through mineralization, and pulp sensibility. The aim of this systematic review was to assess the dentin regeneration efficacy of direct pulp capping (DPC) biomaterials. Methods: The literature published between 2005 and 2021 was searched by using PubMed, Web of Science, Science Direct, Google Scholar, and Scopus databases. Clinical controlled trials, randomized controlled trials, and animal studies investigating DPC outcomes or comparing different capping materials after pulp exposure were included in this systematic review. Three independent authors performed the searches, and information was extracted by using a structured data format. Results: A total of forty studies (21 from humans and 19 from animals) were included in this systemic review. Histological examinations showed complete/partial/incomplete dentin bridge/reparative dentin formation during the pulp healing process at different follow-up periods, using different capping materials. Conclusions: Mineral trioxide aggregate (MTA) and Biodentine can induce dentin regeneration when applied over exposed pulp. This systematic review can conclude that MTA and its variants have better efficacy in the DPC procedure for dentin regeneration.

Nanomaterials Application in Endodontics

In recent years, nanomaterials have become increasingly present in medicine, especially in dentistry. Their characteristics are proving to be very useful in clinical cases. Due to the intense research in the field of biomaterials and nanotechnology, the efficacy and possibilities of dental procedures have immensely expanded over the years. The nano size of materials allows them to exhibit properties not present in their larger-in-scale counterparts. The medical procedures in endodontics are time-consuming and mostly require several visits to be able to achieve the proper result. In this field of dentistry, there are still major issues about the removal of the mostly bacterial infection from the dental root canals. It has been confirmed that nanoparticles are much more efficient than traditional materials and appear to have superior properties when it comes to surface chemistry and bonding. Their unique antibacterial properties are also promising features in every medical procedure, especially in endodontics. High versatility of use of nanomaterials makes them a powerful tool in dental clinics, in a plethora of endodontic procedures, including pulp regeneration, drug delivery, root repair, disinfection, obturation and canal filling. This study focuses on summing up the current knowledge about the utility of nanomaterials in endodontics, their characteristics, advantages, disadvantages, and provides a number of reasons why research in this field should be continued.

The Effect of Calcium-Silicate Cements on Reparative Dentinogenesis Following Direct Pulp Capping on Animal Models

Dental pulp vitality is a desideratum for preserving the health and functionality of the tooth. In certain clinical situations that lead to pulp exposure, bioactive agents are used in direct pulp-capping procedures to stimulate the dentin-pulp complex and activate reparative dentinogenesis. Hydraulic calcium-silicate cements, derived from Portland cement, can induce the formation of a new dentin bridge at the interface between the biomaterial and the dental pulp. Odontoblasts are molecularly activated, and, if necessary, undifferentiated stem cells in the dental pulp can differentiate into odontoblasts. An extensive review of literature was conducted on MedLine/PubMed database to evaluate the histological outcomes of direct pulp capping with hydraulic calcium-silicate cements performed on animal models. Overall, irrespective of their physico-chemical properties and the molecular mechanisms involved in pulp healing, the effects of cements on tertiary dentin formation and pulp vitality preservation were positive. Histological examinations showed different degrees of dental pulp inflammatory response and complete/incomplete dentin bridge formation during the pulp healing process at different follow-up periods. Calcium silicate materials have the ability to induce reparative dentinogenesis when applied over exposed pulps, with different behaviors, as related to the animal model used, pulpal inflammatory responses, and quality of dentin bridges.

Biocompatibility of a HA/β-TCP/C Scaffold as a Pulp-Capping Agent for Vital Pulp Treatment: An In Vivo Study in Rat Molars

Bioceramic materials possess desirable biological properties, highlighting their non-reactivity and osteoconductivity. Their use has been extended in vital pulp treatment. The purpose of this study was to evaluate and compare the effects of beta-tricalcium phosphate (β-TCP), hydroxyapatite (HA), and collagen (C) scaffold with mineral trioxide aggregate (MTA) on the vital pulp of rat molars. Thirty-two molars of Sprague–Dawley rats underwent direct pulp capping with β-TCP/HA/C (n = 16) and MTA (n = 16). After 30 days, the following parameters were evaluated in the tested samples: the degree of pulp inflammation and pulp vitality, the presence of reparative dentin, the homogeneity of the odontoblastic layer, and the presence of pulp fibrosis. No statistically significant differences were observed between HA/β-TCP/C and MTA in terms of the degree of inflammation (p = 0.124). Significant differences were found in reparative dentin formation between the treatment groups (p = 0.0005). Dentin bridge formation was observed in the MTA-treated group. The local action of HA/β-TCP/C is similar to that of MTA when used as an agent for pulp vital treatment in terms of absence of inflammation and maintenance of pulp vitality, although there are significant differences between both materials regarding the formation of dentin bridges.

Minimal Intervention in Dentistry: A Literature Review on Biodentine as a Bioactive Pulp Capping Material

Root canal treatment has been the treatment of choice for carious pulp exposures. In the perspective of minimally invasive dentistry and preventive endodontics, a direct pulp capping procedure with a reliable bioactive material may be considered an alternative approach provided that the pulp status is favorable. However, the treatment of pulp exposure by pulp capping is still a controversial issue with no clear literature available on this topic, leaving the concerned practitioner more confused than satisfied. Biodentine is a relatively new bioactive material explored for vital pulp therapy procedures. This article discusses its role in direct pulp capping procedures. A thorough literature search of the database was done using PubMed, Google Scholar, and Scopus using the keywords preventive endodontics, calcium silicate cement, direct pulp capping, Biodentine, and vital pulp therapy. Reference mining of the articles that were identified was used to locate other papers and enrich the findings. No limits were imposed on the year of publication, but only articles in English were considered. This paper is aimed at reviewing the current literature on Biodentine as a direct pulp capping material. The review will provide a better understanding of Biodentine's properties and can aid in the decision-making process for maintaining the vitality of exposed dental pulp with minimal intervention.

A laboratory study to test the responses of human dental pulp stem cells to extracts from three dental pulp capping biomaterials

AIM

This laboratory study aimed to investigate the effects of three endodontic biomaterials; MTA-HP, iRoot-BP-Plus and ACTIVA on the proliferation, adhesion and osteogenic differentiation of human Dental Pulp Stem Cells (hDPSCs).

METHODOLOGY

The hDPSCs were isolated from the dental pulps of 21 patients scheduled for surgical extraction of their impacted third molars. The MTT assay was used for assessing cellular proliferation. Ninety-six-well plates were used and the experiment was repeated four times under the same condition and the assay was done in triplicate. Four groups were assigned in which the hDPSCs were cultured in complete media only and considered as negative control. Whilst in the 2^nd , 3^rd and 4^th groups, the cells were treated with CM supplemented with 1.5 μl MTA-HP (CM-MTA, iRoot-BP-Plus (CM-BP), and ACTIVA(CM-AC) extracts, respectively. Attachment adhesion and growth morphology of hDPSCs were observed using SEM and the osteogenic differentiation assay was evaluated by Alizarin red stain test (ARS). The data of proliferation and osteogenic differentiation were analysed using two-way ANOVA followed by Tukey's post hoc multiple comparison test. A p-value < 0.05 was considered significant to analyse the differences amongst the means of groups.

RESULTS

Both CM-MTA and CM-BP groups were associated with a significant increase in hDPSC proliferation in comparison with CM-AC and CM groups (p = 0.001). hDPSCs exhibited a greater cellular attachment to iRoot-BP-Plus surfaces followed by MTA-HP, whilst less attachment was observed in the ACTIVA group. Moreover, at day 7 there was a significant difference in formation of mineralizing nodules; CM-BP, CM-MTA and CM-AC groups respectively (p = 0.001). Whilst there was no significance of difference between CM-AC and CM groups (p > 0.05).

CONCLUSIONS

In a laboratory setting, ACTIVA, MTA-HP and iRoot-BP-Plus promoted hDPSCs proliferation, mineralization and attachment, which may explain their in-situ success as endodontic biomaterials.

Cytocompatibility and bioactive properties of the new dual-curing resin-modified calcium silicate-based material for vital pulp therapy

OBJECTIVE

The aim of the present study was to evaluate the in vitro biocompatibility of Theracal PT, Theracal LC, and MTA Angelus, considered as bioactive materials used for vital pulp treatment, on human dental pulp stem cells (hDPSCs).

MATERIALS AND METHODS

Human dental pulp stem cells (hDPSCs) were isolated from third molars, and material eluates were prepared (undiluted, 1:2, and 1:4 ratios). The hDPSC cytotoxicity, adhesion, morphology, viability, and cell migration were assessed. The mineralization nodule formation was determined by Alizarin red S staining (ARS). The odonto/osteogenic differentiation potential was assessed by osteo/odontogenic marker expression real-time qPCR. The chemical composition and ion release of the vital pulp materials were determined by energy dispersive X-ray (EDX) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. Statistical differences were assessed by ANOVA and Tukey's test (p < 0.05).

RESULTS

The three vital pulp materials showed variable levels of calcium, tungsten, silicon, and zirconium release and in their chemical composition. Cytocompatibility assays revealed higher hDPSC viability and migration rates when treated with Theracal PT than with Theracal LC. The lowest cell adhesion and spreading were observed in all Theracal LC-treated groups, whereas the highest were observed when treated with MTA. Theracal PT and MTA promoted the upregulation of DSPP and RUNX2 gene expression (p < 0.05). After 21 days, both MTA Angelus and Theracal PT-treated cells exhibited a significantly higher mineralized nodule formation than the negative control (p < 0.05).

CONCLUSIONS

This study demonstrates the favorable in vitro cytocompatibility and bioactive properties of the recently introduced Theracal PT and the well-established MTA Angelus on hDPSCs, as opposed to Theracal LC. More studies, including in vivo animal testing are suggested before these new formulations might be used in the clinical setting.

CLINICAL RELEVANCE

Theracal PT is a new material that could be clinically suitable for vital pulp therapy. Further studies considering its biocompatibility and bioactivity are necessary.

In vivo Biocompatibility and Bioactivity of Calcium Silicate-Based Bioceramics in Endodontics

Endodontic therapy aims to preserve or repair the activity and function of pulp and periapical tissues. Due to their excellent biological features, a substantial number of calcium silicate-based bioceramics have been introduced into endodontics and simultaneously increased the success rate of endodontic treatment. The present manuscript describes the in vivo biocompatibility and bioactivity of four types of calcium silicate-based bioceramics in endodontics.

Comparative Surface Morphology, Chemical Composition, and Cytocompatibility of Bio-C Repair, Biodentine, and ProRoot MTA on hDPCs

Biocompatibility is an essential property for any vital pulp material that may interact with the dental pulp tissues. Accordingly, this study aimed to compare the chemical composition and ultrastructural morphology of Biodentine (Septodont, Saint Maur-des-Fosses, France), ProRoot MTA (Dentsply Tulsa Dental Specialties, Johnson City, TN, USA), and Bio-C Repair (Angelus, Londrina, PR, Brazil), as well as their biological effects on human dental pulp cells. Chemical element characterization of the materials was undertaken using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX). The cytotoxicity was assessed by analyzing the cell viability (MTT assay), cell morphology (immunofluorescence assay), and cell attachment (flow cytometry assay). The results were statistically analyzed using ANOVA and Tukey’s test (p < 0.05). EDX revealed that ProRoot MTA and Biodentine were mostly composed of calcium, carbon, and oxygen (among others), whereas Bio-C Repair evidenced a low concentration of calcium and the highest concentration of zirconium. SEM showed adequate attachment of human dental pulp cells (hDPCS) to vital pulp materials and cytoskeletal alterations were not observed in the presence of material eluates. Remarkably, the undiluted Biodentine group showed higher viability than the control group cells (without eluates) at 24 h, 48 h, and 72 h (p < 0.001). Based on the evidence derived from an in vitro cellular study, it was concluded that Bio-C Repair showed excellent cytocompatibility that was similar to Biodentine and ProRoot MTA.

Performance of a Biodegradable Composite with Hydroxyapatite as a Scaffold in Pulp Tissue Repair

Vital pulp therapy is an important endodontic treatment. Strategies using growth factors and biological molecules are effective in developing pulp capping materials based on wound healing by the dentin-pulp complex. Our group developed biodegradable viscoelastic polymer materials for tissue-engineered medical devices. The polymer contents help overcome the poor fracture toughness of hydroxyapatite (HAp)-facilitated osteogenic differentiation of pulp cells. However, the composition of this novel polymer remained unclear. This study evaluated a novel polymer composite, P(CL-co-DLLA) and HAp, as a direct pulp capping carrier for biological molecules. The biocompatibility of the novel polymer composite was evaluated by determining the cytotoxicity and proliferation of human dental stem cells in vitro. The novel polymer composite with BMP-2, which reportedly induced tertiary dentin, was tested as a direct pulp capping material in a rat model. Cytotoxicity and proliferation assays revealed that the biocompatibility of the novel polymer composite was similar to that of the control. The novel polymer composite with BMP-2-induced tertiary dentin, similar to hydraulic calcium-silicate cement, in the direct pulp capping model. The BMP-2 composite upregulated wound healing-related gene expression compared to the novel polymer composite alone. Therefore, we suggest that novel polymer composites could be effective carriers for pulp capping.