The efficient elimination of microorganisms and their byproducts from infected root canals is com... more The efficient elimination of microorganisms and their byproducts from infected root canals is compromised by the limitations in conventional root canal disinfection strategies and antimicrobials. Silver nanoparticles (AgNPs) are advantageous for root canal disinfection, mainly due to their wide-spectrum anti-microbial activity. Compared to other commonly used nanoparticulate antibacterials, AgNPs have acceptable antibacterial properties and relatively low cytotoxicity. Owing to their nano-scale, AgNPs penetrate deeper into the complexities of the root canal systems and dentinal tubules, as well as enhancing the antibacterial properties of endodontic irrigants and sealers. AgNPs gradually increase the dentin hardness in endodontically treated teeth and promote antibacterial properties when used as a carrier for intracanal medication. The unique properties of AgNPs make them an ideal additive for different endodontic biomaterials. However, the possible side effects of AgNPs, such as c...
Minimally Invasive Approaches in Endodontic Practice, 2020
Attempting exploration at the expense of dentin tissue to reveal anatomical variation is still a ... more Attempting exploration at the expense of dentin tissue to reveal anatomical variation is still a common practice in root canal treatment, mainly because it relies on bi-dimensional radiographic images and clinical assessments to comprehend root morphology and root canal anatomy. The main purpose of this chapter is to understand the role of technological advances in finding the appropriate resources and maneuvers to (a) completely treat root canal anatomy avoiding residual intracanal infection, (b) balancing the size of the access cavity and the degree of root canal enlargement with the requirements of irrigation methods to achieve optimum disinfection, and (c) preserving root dentin during instrumentation to maintain the mechanical integrity of the root, minimizing the risk of fractures, all of them considered relevant causes of endodontic treatment failure.
OBJECTIVE Considering the variety of pharmacological activities and the potential to mediate biom... more OBJECTIVE Considering the variety of pharmacological activities and the potential to mediate biomineralization, the flavonoids taxifolin and epigallocatechin-3-gallate (EGCG) could be explored as biomolecules in scaffolds for regenerative endodontic procedures. The aim of this study was to evaluate the effect of taxifolin and EGCG on the cell viability, differentiation, and expression of biomineralization markers in stem cells from the apical papilla. DESIGN Stem cells from the apical papilla were exposed to single or continuous treatments with taxifolin at 200, 100 and 50 µM and EGCG at 50, 25 and 12.5 µM for 48 h, 8 and 14 days, in regular or mineralizing media. Cell viability, alkaline phosphatase activity and calcium deposition were analyzed using resazurin, p-nitrophenylphosphate and alizarin-based assays. RESULTS None of the flavonoid groups affected cell viability at 48 h, however at 8 and 14 days, Taxifolin 200 µM and EGCG 50 µM were cytotoxic. Cells did not express alkaline phosphatase activity when grown in regular medium, even in the presence of flavonoids. Alkaline phosphatase activity and biomineralization potential were higher in cells treated with Taxifolin 50 µM and EGCG 12.5 µM. CONCLUSION Taxifolin and EGCG exhibited a concentration, time, and therapeutic mode dependent bioactivity on stem cells from the apical papilla. Both flavonoids at the lower concentrations tested exhibited cytocompatibility and increased expression of mineralization markers in the presence of mineralizing agents.
INTRODUCTION Three-dimension (3D) tissue-construct with a heterogeneous cell population is critic... more INTRODUCTION Three-dimension (3D) tissue-construct with a heterogeneous cell population is critical to understand the interactions between immune cells and stem cells from apical papilla (SCAP) in the periapical region for developing treatment strategies in regenerative endodontics. This study aims to develop and characterize a 3D tissue-construct with binary cell system for studying the interactions between SCAP and macrophages in presence of lipopolysaccharide (LPS - pro-inflammatory) and interleukin-4 (IL-4 - anti-inflammatory) environments. METHODS SCAP and macrophages were seeded in the 3D printed dumbbell-shaped molds to generate tissue-constructs with binary cell population. Two experimental (LPS and IL-4) and control (non-stimulation) conditions were applied to the tissue-constructs to determine the characteristics of the tissue-construct, volume of viable cells and their morphology using a confocal laser scanning microscopy from 0 to 7 days period. Experiments were conducted in triplicates and data were analyzed with trend analysis and two-way analysis of variance at the significance of p < 0.05. RESULTS The tissue-constructs revealed distinct SCAP-macrophage interaction in pro-/anti-inflammatory environments. SCAP displayed characteristic self-organization as a cap-shaped structure in the tissue-construct. The growth of cells and cell-to-cell as well as cell-to-matrix interactions resulted in 70% and 30% decreased dimension of the tissue graft on the SCAP side and macrophage side respectively at day 7 (p < 0.0001). The tissue environments influenced macrophages-SCAP interactions, resulting in altered viable cell volume (p < 0.05), morphology and structural organization. CONCLUSIONS This study developed and characterized an apical papilla organoid in a 3D collagen based tissue-construct for studying SCAP-macrophage crosstalk in tissue regeneration as well as repair.
High‐quality systematic reviews in the field of Dentistry provide the most definitive overarching... more High‐quality systematic reviews in the field of Dentistry provide the most definitive overarching evidence for clinicians, guideline developers and healthcare policy makers to judge the foreseeable risks, anticipated benefits, and potential harms of dental treatment. In the process of carrying out a systematic review, it is essential that authors appraise the methodological quality of the primary studies they include, because studies which follow poor methodology will have a potentially serious negative impact on the overall strength of the evidence and the recommendations that can be drawn. In Endodontology, systematic reviews of laboratory studies have used quality assessment criteria developed subjectively by the individual authors as there are no comprehensive, well‐structured, and universally accepted criteria that can be applied objectively and universally to individual studies included in reviews. Unfortunately, these subjective criteria are likely to be inaccurately defined,...
AIM In order to obtain a 3-dimentional scaffold with predictable clinical results for pulp regene... more AIM In order to obtain a 3-dimentional scaffold with predictable clinical results for pulp regeneration, this study aims to fabricate and characterize a porous decellularized human amniotic membrane (HAM) extracellular matrix (ECM) scaffold, and evaluate its potential to promote pulp regeneration in vitro and in vivo. METHODOLOGY The HAM was decellularized, and its histology and DNA content were analyzed to confirm decellularization. The scaffolds were synthesized with 15, 22.5, and 30 mg/mL concentrations. The porosity, pore size, phosphate buffered saline (PBS) absorption, and degradation rate of the scaffolds were assessed. In vitro experiments were performed on human dental pulp stem cells (hDPSCs) to assess their viability, proliferation, adhesion, and migration on the scaffolds. The optimal group was selected for in vivo immunogenicity assessment and was also used as the cell-free or cell-loaded scaffold in root segment models to evaluate pulp regeneration. All nonparametric data were analyzed with the Kruskal-Wallis test followed by Dunn's post hoc test, while quantitative data were analyzed with one-way ANOVA. RESULTS Decellularization of HAM was confirmed (P<0.05). The porosity of all scaffolds was more than 95%, and the pore size decreased with an increase in ECM concentration (P<0.01). PBS absorption was not significantly different among the groups, while 30 mg/mL ECM scaffold had the highest degradation rate (P<0.01). The hDPSCs adhered to the scaffold, while their proliferation rate increased over time in all groups (P<0.001). Cell migration was higher in 30 mg/mL ECM scaffold (P<0.05). In vivo investigation with 30 mg/mL ECM scaffold revealed mild to moderate inflammatory response. In root segments, both cell-free and cell-loaded 30 mg/mL scaffolds were replaced with newly formed, pulp-like tissue with no significant difference between groups. Immunohistochemical (IHC) assessments revealed high revascularization and collagen content with no significant difference among the groups. CONCLUSION The 30 mg/mL HAM ECM scaffold had optimal physical properties and better supported hDPSC migration. The HAM ECM scaffold did not interfere with formation of pulp-like tissue and revascularization within the root canal when employed as both cell-free and cell-loaded scaffold. These results highlight the potential of HAM ECM membrane for further investigations in regenerative endodontics.
A mature bacterial biofilm is composed of multiple layers of bacteria embedded in a self-made mat... more A mature bacterial biofilm is composed of multiple layers of bacteria embedded in a self-made matrix formed of extracellular polymeric substance. This substance has the potential to modify the response of the resident bacteria to antimicrobials by acting as a shield against the chemical effects of antimicrobials. There is also a localised high density of bacterial cells in a biofilm structure. This spatial arrangement will expose the cells in the deeper layers of the biofilm to less nutrients and redox potential than the cells on the biofilm surface. Since the degree of nutrient and gas gradients increases with the thickness and maturity of a biofilm, the influence of growth rate and oxygen on the antimicrobial resistance is particularly marked in aged biofilm. The resistance associated with biofilm bacteria is further associated with the slow growth rate (starvation) and/or due to the adoption of resistant phenotypes in bacteria residing in a biofilm. It is recognised that no singl...
Introduction: Inconsistencies in the definitions of endodontic outcome terminology jeopardize eva... more Introduction: Inconsistencies in the definitions of endodontic outcome terminology jeopardize evaluations of proposed interventions and patient care quality. This scoping review aimed to provide groundwork to develop a set of basic outcomes in endodontics. Methods: We performed a comprehensive literature search for randomized controlled trials, cohort studies, case-control studies, and case series (10 patients) published after 1980 with patients 10 years of age with any preoperative pulpal and periapical diagnosis in permanent teeth requiring nonsurgical root canal treatment, retreatment, or apexification. Abstracted data on outcome assessment methods, assessors, and domains were reported after univariate and bivariate analyses. Results: Treatment outcomes were evaluated radiographically (88%) or clinically (73%). Although 2-dimensional radiography exceeded 3-dimensional radiography, the use of the latter has increased since 2010, mostly for nonsurgical retreatments. Of 19 identified outcomes, 5 were most frequent: success (168 studies, 40%), radiographic healing (128 studies, 30%), survival (of an asymptomatic tooth [48 studies, 12%] or of a procedure code in administrative databases [31 studies, 7%]), pain assessment (14 studies, 3%), and quality of life (11 studies, 3%). Clinician-centered outcomes have been most frequently studied since the 1980s (71%), in academic settings (76%), and using a prospective design (45%). Patient-centered outcomes were reported in 19% of studies before 2010 and 30% since 2010. They were more common among retrospective studies (49%). Conclusions: Patient-centered outcome measures are lacking in endodontic studies. The state of available research can provide a baseline for the development of a core outcome set in endodontics, which should represent the important patient-centered outcomes in conjunction with well-validated clinician-centered outcomes.
AimTo assess odontogenic differentiation abilities of porous biomineralizable composite scaffolds... more AimTo assess odontogenic differentiation abilities of porous biomineralizable composite scaffolds comprising eggshell derived nano‐hydroxyapatite (HAnp) and carboxymethyl chitosan (CMC) on cultured human dental pulp stem cells (hDPSCs).MethodologyNano‐hydroxyapatite was derived from eggshells using a simple combustion method and CMC was prepared from chitosan through a chemical route. Several compositions of HAnp‐CMC (0:5, 5:0, 1:5, 2:5, 3:5, 4:5 and 1:1 w/w%) scaffolds were prepared by magnetic stirring and freeze‐drying methods. HAnp‐CMC scaffolds were characterized using high‐resolution scanning electron microscopy combined with energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy and X‐ray diffraction methods. In vitro bioactivity was determined following the interaction in simulated body fluid for 21 days. The optimized composite was then loaded onto hDPSCs to assess cell viability/proliferation, dentine sialophosphoprotein (DSPP) and vascular endotheli...
OBJECTIVES The dentin therapeutic agent chlorhexidine has inflammatory and cytotoxic characterist... more OBJECTIVES The dentin therapeutic agent chlorhexidine has inflammatory and cytotoxic characteristics urging investigation of alternatives like the natural compound epigallocatechin-gallate. The aim is to verify the effect of epigallocatechin-gallate and chlorhexidine on viability, interleukin-1β (IL-1β) and differential protein expression of MDPC-23 odontoblast-like cells stimulated by Streptococcus mutans. DESIGN Cells were stimulated with heat-killed S. mutans at multiplicity of infection (MOI) of 100-1000 and subsequently treated with 100-1 µM of epigallocatechin-gallate. Cells with no treatment or chlorhexidine were controls. Combined stimulated/treated cells were tested for cytotoxicity (Alamar-Blue, N = 3, n = 3), total protein (N = 3, n = 3), IL-1β (ELISA, N = 3, n = 3), and differential protein expression by liquid chromatography-tandem mass spectrometry (LC-MS/MS, n = 2). RESULTS Cells stimulated at MOI 100/1000 and treated with 10 µM epigallocatechin-gallate and chlorhexidine did not present cytotoxicity. IL-1β significantly increased in both un-stimulated and stimulated chlorhexidine 10 µM groups when compared to un-treated control (p < 0.05). MOI 100 chlorhexidine 10 µM group significantly increased IL-1β compared to un-stimulated chlorhexidine 10 µM and epigallocatechin-gallate 10 µM groups, as well as to MOI 100 epigallocatechin-gallate 10 µM group (p < 0.05). LC-MS/MS revealed S. mutans and mammalian proteins, with tooth-specific proteins exhibiting different abundance levels, depending on the tested condition. CONCLUSIONS Odontoblast-like cells stimulated with S. mutans at different MOI combined with epigallocatechin-gallate treatment did not cause cytotoxicity. S. mutans stimulation combined with chlorhexidine 100 µM treatment decreased cell viability, while treatment with chlorhexidine 10 µM concentration significantly increased IL-1β. S. mutans stimulation and treatment of cells resulted in varied protein expression.
OBJECTIVES To assess the antimicrobial activity of root canal sealers modified with novel highlyl... more OBJECTIVES To assess the antimicrobial activity of root canal sealers modified with novel highlyloaded antimicrobial drug-silica co-assembled particles (DSPs) on Enterococcus faecalis-infected root canal dentin. METHODS DSPs were synthesized through co-assembly of silica and Octenidine dihydrochloride (OCT) surfactant drug (35%w/w OCT). DSPs (1% wt of the total mass of the sealer) were mixed homogenously with either epoxy-resin sealer (AH) (AH Plus®, Dentsply) or calcium silicatebased sealer (BC) (Bioceramic SealerTM, EndoSequence). To assess the antimicrobial activity of DSP loaded sealers, apical third of single rooted teeth were obtained, and infected with E. faecalis for 3 weeks, followed by the application of experimental (DSPs-loaded) sealers or corresponding controls for up to 28 days. Microbiological analysis, and laser scanning confocal and scanning electron microscopy were used to determine Colony Forming Unit (CFU)/mL, percentage of live bacteria, and intratubular bacterial and sealer penetrations. Factorial ANOVA and Tukey's post hock tests were used to assess the antimicrobial effect of DSPs on different sealers. RESULTS All experimental groups showed significant reductions in CFU at all time points compared to positive controls (P<0.05). The addition of DSPs to BC sealer significantly reduced the CFU (2.11±0.13, 2.22±0.19 and 2.25±0.17 at 1, 7 and 28 days respectively) when compared to the unmodified sealer (3.21±0.11, 4.3±0.15 and 4.2±0.2 at 0, 7 and 28 days. DSPs enhanced antimicrobial performance of AH only at 1 day (4.21± 0.17 vs. 5.19±0.12, P<0.05). AH and AH+DSP showed higher bacterial viability compared to BC sealer and BC+DSP at all incubation periods (P<0.05). CONCLUSIONS Loading endodontic sealers with DSPs had a material-dependent effect on the antimicrobial properties and could reduce the incidence of secondary infections.
Animal testing is crucial in situations when research on humans is not allowed because of unknown... more Animal testing is crucial in situations when research on humans is not allowed because of unknown health risks and ethical concerns. The current project aims to develop reporting guidelines exclusively for animal studies in Endodontology, using an established consensus‐based methodology. The guidelines have been named: Preferred Reporting Items for Animal Studies in Endodontology (PRIASE) 2021. Nine individuals (PD, VN, AK, PM, MN, JF, EP, JJ and SJ), including the project leaders (PD, VN) formed a steering committee. The steering committee developed a novel checklist by adapting and integrating their animal testing and peer review experience with the Animals in Research: Reporting In Vivo Experiments (ARRIVE) guidelines and also the Clinical and Laboratory Images in Publications (CLIP) principles. A PRIASE Delphi Group (PDG) and PRIASE Online Meeting Group (POMG) were also formed. Thirty‐one PDG members participated in the online Delphi process and achieved consensus on the checkli...
Background: Clinical research is important to evaluate the effect of desensitizing agents. Aims: ... more Background: Clinical research is important to evaluate the effect of desensitizing agents. Aims: This randomized clinical trial evaluated the immediate and 1 week desensitizing effect of two desensitizing agents Uno Topical Gel and Profluorid. Materials and Methods: Thirtyfive patients with teeth presenting with dentin hypersensitivity were included in this clinical trial. Each quadrant in a patient was randomly assigned to one of two groups: Uno Topical Gel or Profluorid Varnish. A VAS score was used to assess tooth sensitivity at baseline, immediately after application of desensitizer and after 1 week. Additionally, 30 dentin discs were prepared, divided into Group 1(Control Group), Group 2 (Profluorid Varnish) and Group 3 (Uno Topical Gel) and examined using scanning electron microscopy (SEM) after 1hour and 24 hours to evaluate tubule occlusion. Statistical Analysis: Clinical data were analysed using Friedman's test and Mann – Whitney U test. SEM data was analysed using Student's 2-sample t-test. Results: Uno group was significantly better to evaporative stimuli immediately (P=0.01) after application. After 1 week, Uno group was significantly better to tactile (P=0.000) and evaporative (P=0.000) stimuli than Profluorid. SEM images showed that 1 hour after application, Uno and Profluorid demonstrated more than 90% and 80% dentin tubule occlusion respectively. At 24 hours, Uno and Profluorid demonstrated more than 50% and 60% dentin tubule occlusion respectively. Conclusions: Uno Topical Gel was significantly better than Profluorid in reducing pain of dentin hypersensitivity due to tactile and evaporative stimuli after 1 week.
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, 2019
The effects of physical photostimulable phosphor plate artifacts on the radiologic interpretation... more The effects of physical photostimulable phosphor plate artifacts on the radiologic interpretation of periapical inflammatory disease.
Objective. To evaluate the protease activity in dentin matrices subjected to lactic acid (LA) in ... more Objective. To evaluate the protease activity in dentin matrices subjected to lactic acid (LA) in comparison to polyacrylic acid (PAA) challenge model at cathepsin K (CT-K) optimum pH 5.5 to assess effectiveness of inhibitors in dentin collagen degradation. Methods. Dentin disks measuring 0.5 mm prepared from human molars were completely demineralized in 10% H 3 PO 4. Demineralized dentin disks were challenged with 0.1 M LA, 1.1 mM PAA, artificial saliva (AS), or deionized water (C) for 24 h or 7-days. Dentin collagen properties were tested by measurement of %dry mass change, and ultimate tensile strength (UTS). Degradation of dentin type I collagen was measured by telopeptide assays measuring the sub-product release of C-terminal cross-linked telopeptides (ICTP) and C-terminal peptide (CTX) in the incubation media in relation to total protein concentration, which correlates with matrix metalloproteinases (MMPs) and CT-K activities. Results. Gravimetric analysis showed statistically significant difference between C and other groups (p < 0.04) at 24 h. LA specimens showed significantly higher weight loss from 24 h to 7-days (p = 0.02). UTS revealed statistically significant difference between AS and LA at 24 h and 7-days. UTS at 24 h and 7-days for C and AS had significantly higher mean values compared to LA and PAA. Telopeptide assays reported that CTX tp results showed that LA at 24 h had significantly higher mean values compared to C and AS. Significance. LA has the ability to activate endogenous CT-K in dentin as measured by the release of CTX (CT-K specific telopeptide). This LA based model has the potential application for further investigations on the activity and possible inhibitors of CT-K in human dentin.
Introduction: This in vivo study aimed to evaluate the development of dentinal microcracks after ... more Introduction: This in vivo study aimed to evaluate the development of dentinal microcracks after root canal preparation of contralateral premolars with rotary or hand instruments using micro-computed tomographic technology. Methods: Sixty contralateral intact maxillary and mandibular premolars in which extraction was indicated for orthodontic purposes were selected and distributed into positive (n 5 6, teeth with induced root microcracks) and negative (n 5 6, intact teeth) control groups as well as 2 experimental groups (n 5 24) according to the instrumentation protocol: ProTaper rotary (PTR) or ProTaper hand (PTH) systems (Dentsply Maillefer, Ballaigues, Switzerland). After root canal preparation, teeth were extracted using an atraumatic technique and scanned at a resolution of 17.18 mm. A total of 43,361 cross-sectional images of the roots were screened for the presence of dentinal microcracks. The results were expressed as the percentage and number of root section images with microcracks for each group. Results: All roots in the positive control group showed microcracks at the apical third, whereas no cracks were observed in the specimens of the negative control group. In the PTR group, 17,114 cross-sectional images were analyzed, and no microcrack was observed. In the PTH group, dentinal microcracks were observed in 116 of 17,408 cross-sectional slices (0.66%) of only 1 specimen. These incomplete microcracks extended from the external root surface into the inner root dentin at the area of reduced dentin thickness. Conclusions: Root canal instrumentation with PTR and PTH instruments of contralateral maxillary and mandibular premolars did not result in the formation of dentinal microcracks in vivo. (
The efficient elimination of microorganisms and their byproducts from infected root canals is com... more The efficient elimination of microorganisms and their byproducts from infected root canals is compromised by the limitations in conventional root canal disinfection strategies and antimicrobials. Silver nanoparticles (AgNPs) are advantageous for root canal disinfection, mainly due to their wide-spectrum anti-microbial activity. Compared to other commonly used nanoparticulate antibacterials, AgNPs have acceptable antibacterial properties and relatively low cytotoxicity. Owing to their nano-scale, AgNPs penetrate deeper into the complexities of the root canal systems and dentinal tubules, as well as enhancing the antibacterial properties of endodontic irrigants and sealers. AgNPs gradually increase the dentin hardness in endodontically treated teeth and promote antibacterial properties when used as a carrier for intracanal medication. The unique properties of AgNPs make them an ideal additive for different endodontic biomaterials. However, the possible side effects of AgNPs, such as c...
Minimally Invasive Approaches in Endodontic Practice, 2020
Attempting exploration at the expense of dentin tissue to reveal anatomical variation is still a ... more Attempting exploration at the expense of dentin tissue to reveal anatomical variation is still a common practice in root canal treatment, mainly because it relies on bi-dimensional radiographic images and clinical assessments to comprehend root morphology and root canal anatomy. The main purpose of this chapter is to understand the role of technological advances in finding the appropriate resources and maneuvers to (a) completely treat root canal anatomy avoiding residual intracanal infection, (b) balancing the size of the access cavity and the degree of root canal enlargement with the requirements of irrigation methods to achieve optimum disinfection, and (c) preserving root dentin during instrumentation to maintain the mechanical integrity of the root, minimizing the risk of fractures, all of them considered relevant causes of endodontic treatment failure.
OBJECTIVE Considering the variety of pharmacological activities and the potential to mediate biom... more OBJECTIVE Considering the variety of pharmacological activities and the potential to mediate biomineralization, the flavonoids taxifolin and epigallocatechin-3-gallate (EGCG) could be explored as biomolecules in scaffolds for regenerative endodontic procedures. The aim of this study was to evaluate the effect of taxifolin and EGCG on the cell viability, differentiation, and expression of biomineralization markers in stem cells from the apical papilla. DESIGN Stem cells from the apical papilla were exposed to single or continuous treatments with taxifolin at 200, 100 and 50 µM and EGCG at 50, 25 and 12.5 µM for 48 h, 8 and 14 days, in regular or mineralizing media. Cell viability, alkaline phosphatase activity and calcium deposition were analyzed using resazurin, p-nitrophenylphosphate and alizarin-based assays. RESULTS None of the flavonoid groups affected cell viability at 48 h, however at 8 and 14 days, Taxifolin 200 µM and EGCG 50 µM were cytotoxic. Cells did not express alkaline phosphatase activity when grown in regular medium, even in the presence of flavonoids. Alkaline phosphatase activity and biomineralization potential were higher in cells treated with Taxifolin 50 µM and EGCG 12.5 µM. CONCLUSION Taxifolin and EGCG exhibited a concentration, time, and therapeutic mode dependent bioactivity on stem cells from the apical papilla. Both flavonoids at the lower concentrations tested exhibited cytocompatibility and increased expression of mineralization markers in the presence of mineralizing agents.
INTRODUCTION Three-dimension (3D) tissue-construct with a heterogeneous cell population is critic... more INTRODUCTION Three-dimension (3D) tissue-construct with a heterogeneous cell population is critical to understand the interactions between immune cells and stem cells from apical papilla (SCAP) in the periapical region for developing treatment strategies in regenerative endodontics. This study aims to develop and characterize a 3D tissue-construct with binary cell system for studying the interactions between SCAP and macrophages in presence of lipopolysaccharide (LPS - pro-inflammatory) and interleukin-4 (IL-4 - anti-inflammatory) environments. METHODS SCAP and macrophages were seeded in the 3D printed dumbbell-shaped molds to generate tissue-constructs with binary cell population. Two experimental (LPS and IL-4) and control (non-stimulation) conditions were applied to the tissue-constructs to determine the characteristics of the tissue-construct, volume of viable cells and their morphology using a confocal laser scanning microscopy from 0 to 7 days period. Experiments were conducted in triplicates and data were analyzed with trend analysis and two-way analysis of variance at the significance of p < 0.05. RESULTS The tissue-constructs revealed distinct SCAP-macrophage interaction in pro-/anti-inflammatory environments. SCAP displayed characteristic self-organization as a cap-shaped structure in the tissue-construct. The growth of cells and cell-to-cell as well as cell-to-matrix interactions resulted in 70% and 30% decreased dimension of the tissue graft on the SCAP side and macrophage side respectively at day 7 (p < 0.0001). The tissue environments influenced macrophages-SCAP interactions, resulting in altered viable cell volume (p < 0.05), morphology and structural organization. CONCLUSIONS This study developed and characterized an apical papilla organoid in a 3D collagen based tissue-construct for studying SCAP-macrophage crosstalk in tissue regeneration as well as repair.
High‐quality systematic reviews in the field of Dentistry provide the most definitive overarching... more High‐quality systematic reviews in the field of Dentistry provide the most definitive overarching evidence for clinicians, guideline developers and healthcare policy makers to judge the foreseeable risks, anticipated benefits, and potential harms of dental treatment. In the process of carrying out a systematic review, it is essential that authors appraise the methodological quality of the primary studies they include, because studies which follow poor methodology will have a potentially serious negative impact on the overall strength of the evidence and the recommendations that can be drawn. In Endodontology, systematic reviews of laboratory studies have used quality assessment criteria developed subjectively by the individual authors as there are no comprehensive, well‐structured, and universally accepted criteria that can be applied objectively and universally to individual studies included in reviews. Unfortunately, these subjective criteria are likely to be inaccurately defined,...
AIM In order to obtain a 3-dimentional scaffold with predictable clinical results for pulp regene... more AIM In order to obtain a 3-dimentional scaffold with predictable clinical results for pulp regeneration, this study aims to fabricate and characterize a porous decellularized human amniotic membrane (HAM) extracellular matrix (ECM) scaffold, and evaluate its potential to promote pulp regeneration in vitro and in vivo. METHODOLOGY The HAM was decellularized, and its histology and DNA content were analyzed to confirm decellularization. The scaffolds were synthesized with 15, 22.5, and 30 mg/mL concentrations. The porosity, pore size, phosphate buffered saline (PBS) absorption, and degradation rate of the scaffolds were assessed. In vitro experiments were performed on human dental pulp stem cells (hDPSCs) to assess their viability, proliferation, adhesion, and migration on the scaffolds. The optimal group was selected for in vivo immunogenicity assessment and was also used as the cell-free or cell-loaded scaffold in root segment models to evaluate pulp regeneration. All nonparametric data were analyzed with the Kruskal-Wallis test followed by Dunn's post hoc test, while quantitative data were analyzed with one-way ANOVA. RESULTS Decellularization of HAM was confirmed (P<0.05). The porosity of all scaffolds was more than 95%, and the pore size decreased with an increase in ECM concentration (P<0.01). PBS absorption was not significantly different among the groups, while 30 mg/mL ECM scaffold had the highest degradation rate (P<0.01). The hDPSCs adhered to the scaffold, while their proliferation rate increased over time in all groups (P<0.001). Cell migration was higher in 30 mg/mL ECM scaffold (P<0.05). In vivo investigation with 30 mg/mL ECM scaffold revealed mild to moderate inflammatory response. In root segments, both cell-free and cell-loaded 30 mg/mL scaffolds were replaced with newly formed, pulp-like tissue with no significant difference between groups. Immunohistochemical (IHC) assessments revealed high revascularization and collagen content with no significant difference among the groups. CONCLUSION The 30 mg/mL HAM ECM scaffold had optimal physical properties and better supported hDPSC migration. The HAM ECM scaffold did not interfere with formation of pulp-like tissue and revascularization within the root canal when employed as both cell-free and cell-loaded scaffold. These results highlight the potential of HAM ECM membrane for further investigations in regenerative endodontics.
A mature bacterial biofilm is composed of multiple layers of bacteria embedded in a self-made mat... more A mature bacterial biofilm is composed of multiple layers of bacteria embedded in a self-made matrix formed of extracellular polymeric substance. This substance has the potential to modify the response of the resident bacteria to antimicrobials by acting as a shield against the chemical effects of antimicrobials. There is also a localised high density of bacterial cells in a biofilm structure. This spatial arrangement will expose the cells in the deeper layers of the biofilm to less nutrients and redox potential than the cells on the biofilm surface. Since the degree of nutrient and gas gradients increases with the thickness and maturity of a biofilm, the influence of growth rate and oxygen on the antimicrobial resistance is particularly marked in aged biofilm. The resistance associated with biofilm bacteria is further associated with the slow growth rate (starvation) and/or due to the adoption of resistant phenotypes in bacteria residing in a biofilm. It is recognised that no singl...
Introduction: Inconsistencies in the definitions of endodontic outcome terminology jeopardize eva... more Introduction: Inconsistencies in the definitions of endodontic outcome terminology jeopardize evaluations of proposed interventions and patient care quality. This scoping review aimed to provide groundwork to develop a set of basic outcomes in endodontics. Methods: We performed a comprehensive literature search for randomized controlled trials, cohort studies, case-control studies, and case series (10 patients) published after 1980 with patients 10 years of age with any preoperative pulpal and periapical diagnosis in permanent teeth requiring nonsurgical root canal treatment, retreatment, or apexification. Abstracted data on outcome assessment methods, assessors, and domains were reported after univariate and bivariate analyses. Results: Treatment outcomes were evaluated radiographically (88%) or clinically (73%). Although 2-dimensional radiography exceeded 3-dimensional radiography, the use of the latter has increased since 2010, mostly for nonsurgical retreatments. Of 19 identified outcomes, 5 were most frequent: success (168 studies, 40%), radiographic healing (128 studies, 30%), survival (of an asymptomatic tooth [48 studies, 12%] or of a procedure code in administrative databases [31 studies, 7%]), pain assessment (14 studies, 3%), and quality of life (11 studies, 3%). Clinician-centered outcomes have been most frequently studied since the 1980s (71%), in academic settings (76%), and using a prospective design (45%). Patient-centered outcomes were reported in 19% of studies before 2010 and 30% since 2010. They were more common among retrospective studies (49%). Conclusions: Patient-centered outcome measures are lacking in endodontic studies. The state of available research can provide a baseline for the development of a core outcome set in endodontics, which should represent the important patient-centered outcomes in conjunction with well-validated clinician-centered outcomes.
AimTo assess odontogenic differentiation abilities of porous biomineralizable composite scaffolds... more AimTo assess odontogenic differentiation abilities of porous biomineralizable composite scaffolds comprising eggshell derived nano‐hydroxyapatite (HAnp) and carboxymethyl chitosan (CMC) on cultured human dental pulp stem cells (hDPSCs).MethodologyNano‐hydroxyapatite was derived from eggshells using a simple combustion method and CMC was prepared from chitosan through a chemical route. Several compositions of HAnp‐CMC (0:5, 5:0, 1:5, 2:5, 3:5, 4:5 and 1:1 w/w%) scaffolds were prepared by magnetic stirring and freeze‐drying methods. HAnp‐CMC scaffolds were characterized using high‐resolution scanning electron microscopy combined with energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy and X‐ray diffraction methods. In vitro bioactivity was determined following the interaction in simulated body fluid for 21 days. The optimized composite was then loaded onto hDPSCs to assess cell viability/proliferation, dentine sialophosphoprotein (DSPP) and vascular endotheli...
OBJECTIVES The dentin therapeutic agent chlorhexidine has inflammatory and cytotoxic characterist... more OBJECTIVES The dentin therapeutic agent chlorhexidine has inflammatory and cytotoxic characteristics urging investigation of alternatives like the natural compound epigallocatechin-gallate. The aim is to verify the effect of epigallocatechin-gallate and chlorhexidine on viability, interleukin-1β (IL-1β) and differential protein expression of MDPC-23 odontoblast-like cells stimulated by Streptococcus mutans. DESIGN Cells were stimulated with heat-killed S. mutans at multiplicity of infection (MOI) of 100-1000 and subsequently treated with 100-1 µM of epigallocatechin-gallate. Cells with no treatment or chlorhexidine were controls. Combined stimulated/treated cells were tested for cytotoxicity (Alamar-Blue, N = 3, n = 3), total protein (N = 3, n = 3), IL-1β (ELISA, N = 3, n = 3), and differential protein expression by liquid chromatography-tandem mass spectrometry (LC-MS/MS, n = 2). RESULTS Cells stimulated at MOI 100/1000 and treated with 10 µM epigallocatechin-gallate and chlorhexidine did not present cytotoxicity. IL-1β significantly increased in both un-stimulated and stimulated chlorhexidine 10 µM groups when compared to un-treated control (p < 0.05). MOI 100 chlorhexidine 10 µM group significantly increased IL-1β compared to un-stimulated chlorhexidine 10 µM and epigallocatechin-gallate 10 µM groups, as well as to MOI 100 epigallocatechin-gallate 10 µM group (p < 0.05). LC-MS/MS revealed S. mutans and mammalian proteins, with tooth-specific proteins exhibiting different abundance levels, depending on the tested condition. CONCLUSIONS Odontoblast-like cells stimulated with S. mutans at different MOI combined with epigallocatechin-gallate treatment did not cause cytotoxicity. S. mutans stimulation combined with chlorhexidine 100 µM treatment decreased cell viability, while treatment with chlorhexidine 10 µM concentration significantly increased IL-1β. S. mutans stimulation and treatment of cells resulted in varied protein expression.
OBJECTIVES To assess the antimicrobial activity of root canal sealers modified with novel highlyl... more OBJECTIVES To assess the antimicrobial activity of root canal sealers modified with novel highlyloaded antimicrobial drug-silica co-assembled particles (DSPs) on Enterococcus faecalis-infected root canal dentin. METHODS DSPs were synthesized through co-assembly of silica and Octenidine dihydrochloride (OCT) surfactant drug (35%w/w OCT). DSPs (1% wt of the total mass of the sealer) were mixed homogenously with either epoxy-resin sealer (AH) (AH Plus®, Dentsply) or calcium silicatebased sealer (BC) (Bioceramic SealerTM, EndoSequence). To assess the antimicrobial activity of DSP loaded sealers, apical third of single rooted teeth were obtained, and infected with E. faecalis for 3 weeks, followed by the application of experimental (DSPs-loaded) sealers or corresponding controls for up to 28 days. Microbiological analysis, and laser scanning confocal and scanning electron microscopy were used to determine Colony Forming Unit (CFU)/mL, percentage of live bacteria, and intratubular bacterial and sealer penetrations. Factorial ANOVA and Tukey's post hock tests were used to assess the antimicrobial effect of DSPs on different sealers. RESULTS All experimental groups showed significant reductions in CFU at all time points compared to positive controls (P<0.05). The addition of DSPs to BC sealer significantly reduced the CFU (2.11±0.13, 2.22±0.19 and 2.25±0.17 at 1, 7 and 28 days respectively) when compared to the unmodified sealer (3.21±0.11, 4.3±0.15 and 4.2±0.2 at 0, 7 and 28 days. DSPs enhanced antimicrobial performance of AH only at 1 day (4.21± 0.17 vs. 5.19±0.12, P<0.05). AH and AH+DSP showed higher bacterial viability compared to BC sealer and BC+DSP at all incubation periods (P<0.05). CONCLUSIONS Loading endodontic sealers with DSPs had a material-dependent effect on the antimicrobial properties and could reduce the incidence of secondary infections.
Animal testing is crucial in situations when research on humans is not allowed because of unknown... more Animal testing is crucial in situations when research on humans is not allowed because of unknown health risks and ethical concerns. The current project aims to develop reporting guidelines exclusively for animal studies in Endodontology, using an established consensus‐based methodology. The guidelines have been named: Preferred Reporting Items for Animal Studies in Endodontology (PRIASE) 2021. Nine individuals (PD, VN, AK, PM, MN, JF, EP, JJ and SJ), including the project leaders (PD, VN) formed a steering committee. The steering committee developed a novel checklist by adapting and integrating their animal testing and peer review experience with the Animals in Research: Reporting In Vivo Experiments (ARRIVE) guidelines and also the Clinical and Laboratory Images in Publications (CLIP) principles. A PRIASE Delphi Group (PDG) and PRIASE Online Meeting Group (POMG) were also formed. Thirty‐one PDG members participated in the online Delphi process and achieved consensus on the checkli...
Background: Clinical research is important to evaluate the effect of desensitizing agents. Aims: ... more Background: Clinical research is important to evaluate the effect of desensitizing agents. Aims: This randomized clinical trial evaluated the immediate and 1 week desensitizing effect of two desensitizing agents Uno Topical Gel and Profluorid. Materials and Methods: Thirtyfive patients with teeth presenting with dentin hypersensitivity were included in this clinical trial. Each quadrant in a patient was randomly assigned to one of two groups: Uno Topical Gel or Profluorid Varnish. A VAS score was used to assess tooth sensitivity at baseline, immediately after application of desensitizer and after 1 week. Additionally, 30 dentin discs were prepared, divided into Group 1(Control Group), Group 2 (Profluorid Varnish) and Group 3 (Uno Topical Gel) and examined using scanning electron microscopy (SEM) after 1hour and 24 hours to evaluate tubule occlusion. Statistical Analysis: Clinical data were analysed using Friedman's test and Mann – Whitney U test. SEM data was analysed using Student's 2-sample t-test. Results: Uno group was significantly better to evaporative stimuli immediately (P=0.01) after application. After 1 week, Uno group was significantly better to tactile (P=0.000) and evaporative (P=0.000) stimuli than Profluorid. SEM images showed that 1 hour after application, Uno and Profluorid demonstrated more than 90% and 80% dentin tubule occlusion respectively. At 24 hours, Uno and Profluorid demonstrated more than 50% and 60% dentin tubule occlusion respectively. Conclusions: Uno Topical Gel was significantly better than Profluorid in reducing pain of dentin hypersensitivity due to tactile and evaporative stimuli after 1 week.
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, 2019
The effects of physical photostimulable phosphor plate artifacts on the radiologic interpretation... more The effects of physical photostimulable phosphor plate artifacts on the radiologic interpretation of periapical inflammatory disease.
Objective. To evaluate the protease activity in dentin matrices subjected to lactic acid (LA) in ... more Objective. To evaluate the protease activity in dentin matrices subjected to lactic acid (LA) in comparison to polyacrylic acid (PAA) challenge model at cathepsin K (CT-K) optimum pH 5.5 to assess effectiveness of inhibitors in dentin collagen degradation. Methods. Dentin disks measuring 0.5 mm prepared from human molars were completely demineralized in 10% H 3 PO 4. Demineralized dentin disks were challenged with 0.1 M LA, 1.1 mM PAA, artificial saliva (AS), or deionized water (C) for 24 h or 7-days. Dentin collagen properties were tested by measurement of %dry mass change, and ultimate tensile strength (UTS). Degradation of dentin type I collagen was measured by telopeptide assays measuring the sub-product release of C-terminal cross-linked telopeptides (ICTP) and C-terminal peptide (CTX) in the incubation media in relation to total protein concentration, which correlates with matrix metalloproteinases (MMPs) and CT-K activities. Results. Gravimetric analysis showed statistically significant difference between C and other groups (p < 0.04) at 24 h. LA specimens showed significantly higher weight loss from 24 h to 7-days (p = 0.02). UTS revealed statistically significant difference between AS and LA at 24 h and 7-days. UTS at 24 h and 7-days for C and AS had significantly higher mean values compared to LA and PAA. Telopeptide assays reported that CTX tp results showed that LA at 24 h had significantly higher mean values compared to C and AS. Significance. LA has the ability to activate endogenous CT-K in dentin as measured by the release of CTX (CT-K specific telopeptide). This LA based model has the potential application for further investigations on the activity and possible inhibitors of CT-K in human dentin.
Introduction: This in vivo study aimed to evaluate the development of dentinal microcracks after ... more Introduction: This in vivo study aimed to evaluate the development of dentinal microcracks after root canal preparation of contralateral premolars with rotary or hand instruments using micro-computed tomographic technology. Methods: Sixty contralateral intact maxillary and mandibular premolars in which extraction was indicated for orthodontic purposes were selected and distributed into positive (n 5 6, teeth with induced root microcracks) and negative (n 5 6, intact teeth) control groups as well as 2 experimental groups (n 5 24) according to the instrumentation protocol: ProTaper rotary (PTR) or ProTaper hand (PTH) systems (Dentsply Maillefer, Ballaigues, Switzerland). After root canal preparation, teeth were extracted using an atraumatic technique and scanned at a resolution of 17.18 mm. A total of 43,361 cross-sectional images of the roots were screened for the presence of dentinal microcracks. The results were expressed as the percentage and number of root section images with microcracks for each group. Results: All roots in the positive control group showed microcracks at the apical third, whereas no cracks were observed in the specimens of the negative control group. In the PTR group, 17,114 cross-sectional images were analyzed, and no microcrack was observed. In the PTH group, dentinal microcracks were observed in 116 of 17,408 cross-sectional slices (0.66%) of only 1 specimen. These incomplete microcracks extended from the external root surface into the inner root dentin at the area of reduced dentin thickness. Conclusions: Root canal instrumentation with PTR and PTH instruments of contralateral maxillary and mandibular premolars did not result in the formation of dentinal microcracks in vivo. (
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