The COVID-19 pandemic, still on the growth curve, has had a devastating effect on the dental health sector for the past 3 months. This has become an area of enormous concern for the dentists professionally and the patients in terms of dental health. Dentistry at this point needs a complete structural change to prevent cross-infection among the patients and dentists owing to the unique characteristic of a dental health-care setting as well as to offer a sense of safety and security to the patients. This article highlights the salient points to be considered for the post-COVID phase in dentistry.

Elimination of bacteria from infected root canal systems is a challenging task. Various techniques have been described to reduce the number of bacteria within the root canal system, which include chemomechanical instrumentation, use of various irrigants to remove or dissolve organic and inorganic debris, and to destroy bacteria. The intracanal medicament plays a key role in the success of root canal treatment. With the rise in bacterial resistance to antibiotics, there is considerable interest in the development of other classes of antimicrobials for the control of infection. Natural products are known to play an important role in human life. The use of herbal products as mouthwash has been tried and tested in the literature. However, the use of herbal intracanal medicament has been shown promising results when used under in vitro conditions, but in vivo studies are very scarce. This may be due to the limited supporting literature available to use it as intracanal medicament in patients due to the ethical concern. Hence, the purpose of this review is to highlight the current guidelines (laid by the drugs and cosmetics act as per the Gazette of India) regarding the use of herbal medicaments for the clinical trials in endodontics.

Background: Platelet concentrates are extensively utilized in the medical and dental field to promote tissue regeneration. The profusion of endogenous growth factors in platelets α-granules transmit their use for enhanced wound healing. However, little attention has been given to study their antimicrobial potential. This study was conducted to assess the antibacterial and antifungal property of platelet-rich fibrin (PRF) and PRF matrix (PRFM). Materials and Methodology: Blood samples were obtained from 16 participants, PRF and PRFM were processed as per the protocol prescribed by Choukroun et al. and Lucarelli et al., respectively. The susceptibility test against microbiota in the root canal and Candida albicans was assessed through minimum inhibition zone by agar diffusion technique. Results: PRF showed an effective antibacterial property, however, did not perform well against C. albicans strains. PRFM did not show any antibacterial or antifungal properties. Conclusions: The antibacterial efficacy of PRF may prove beneficial when used in the revascularization procedure of immature necrotic teeth.

Aim: The aim of this study is to evaluate and compare the fracture resistance of endodontically treated teeth using four intraorifice barriers. Materials and Methods: Fifty extracted single-rooted mandibular premolars were selected, decoronated, and prepared with rotary Protaper universal system and obturated with gutta-percha and AH Plus sealer. Samples were divided into five groups (n = 10) on the basis of intraorifice barrier material used. Group 1: Biodentine, Group 2: Conventional glass ionomer cement (GIC), Group 3: Resin-modified glass ionomer cement (RMGIC), Group 4: Nanohybrid composite, Group 5: No barrier (control).Except for control specimens, coronal 3-mm gutta-percha was removed and filled with different intraorifice barrier materials in respective groups. Fracture resistance of specimens was tested using universal testing machine. Statistical Analysis Used: One-way analysis of variance test and Post hoc Tukey's test. Results: Mean fracture resistance of all experimental groups (with intraorifice barriers placed) were higher than control group (no intraorifice barrier placed). Biodentine showed the highest mean fracture resistance while RMGIC showed the least and the difference between their mean fracture resistance was statistically significant. There was no statistically significant difference among other experimental groups. Conclusion: Placement of intraorifice barriers in endodontically treated teeth can significantly increase fracture resistance and this increase in fracture resistance is material dependent.

Aims: The aim of this study is to compare three different methods of measuring root canal curvature and its correlation with canal access angle (CAA) in curved mesiobuccal canals of permanent mandibular first molars. Materials and Methods: Sixty human mandibular first molars were used in this study. Standardized access cavities were prepared. After endodontic access, a size 10 K-file was placed in the mesiobuccal canal extending to the apical foramen, and radiographs were taken. Radiographs of each root canal were taken in buccolingual direction with the long axis of the root perpendicular to the central X-ray beam. After that, the radiographs were scanned with a computer Scanner. The angles were measured using the Schneider method, Weine's method, Lutein's method, and correlated with the CAA method. The angular and linear values used in this study were plotted, and the pertinent measurements were made using the program AutoCAD R12. Statistical Analysis: The resultant values were evaluated statistically using ANOVA test and Pearson correlation and multiple regression analyses (P = 0.001). Results: Lutein's method is as effective as the Schneider's method, Wein's method and CAA. method in evaluating root canal curvature. Conclusions: Scheider/Wein/Luiten method, together with CAA method, may be considered as a reliable guideline for preoperative assessment of canal curvature.

Aim: The aim of this study is to clinically isolate and detect three anaerobic bacteria associated with endodontic-periodontal lesions in type-2 diabetic and nondiabetic patients using polymerase chain reaction (PCR). Materials and Methods: Sixty patients presenting endodontic-periodontal lesions were divided into two groups. Thirty patients with type-2 diabetics (Group 1) and 30 nondiabetic patients (Group 2) were evaluated for the presence of three anaerobic bacteria. Clinical examinations, periapical radiographs, and microbiological sampling from the canal system and periodontal pockets were performed. Qualitative evaluation of bacteria was performed using a multiplex PCR for Porphyromonas gingivalis and Prevotella intermedia. Statistical analysis was performed using Pearson's Chi-square test and Fischer's exact test. Results: Enterococcus faecalis (73.3%) was the predominant bacteria isolated from the root canal in type 2 diabetic patients, followed by P. gingivalis (70%) and P. intermedia (36%) compared to 53.3%, 43.3%, and 23.3%, respectively, among nondiabetic patients. P. gingivalis (73.3%) was the predominant bacteria isolated from periodontal pockets in type II diabetic patients followed by P. intermedia 50% and E. faecalis 30% compared to 36.6%, 33.3%, and 30%, respectively, among nondiabetics. P. gingivalis was detected in the root canal and periodontal pocket in almost similar numbers (70% and 73%), respectively, among type-2 diabetics. Conclusion: Detection of P. gingivalis, P. intermedia, and E. faecalis in both root canal and periodontal pocket samples confirm a viable pathway for the spread of infection through dual sites. Since in the present study, P. gingivalis was found to be present in similar numbers in dual sites among type 2 diabetic patients, importance should be given in treating such anaerobic bacteria in immune-compromised patients.

Aims: The aim of this study is to evaluate in vitro the effect of application of bromelain enzyme on the microleakage of composite resin restorations after external tooth bleaching using spectrophotometric evaluation. Subjects and Methods: Buccal Class V cavities were prepared on the surface of fifty intact premolars, which were randomly divided into five groups. All cavities were filled with composite resin.

• Group I: Teeth were not bleached but restored (n = 10). External bleaching with 35% hydrogen peroxide was carried out for the rest of the specimens
• Group II: Cavities were restored immediately after bleaching (n = 10)
• Group III: Cavities were restored after a delay of 3 weeks (n = 10)
• Group IV: Cavities were treated with sodium ascorbate after bleaching and then restored (n = 10)
• Group V: Cavities were treated with bromelain enzyme solution after bleaching and then restored (n = 10).

Microleakage was assessed by the dye extraction method using a spectrophotometer. Statistical Analysis Used: The data were analyzed statistically by comparison of mean microleakage and post hoc test using SPSS 2.0 software. Results: Group I displayed the least amount of microleakage, whereas Group II showed the greatest amount of microleakage (P < 0.05). Groups III, IV, and V showed a significantly lower amount of microleakage compared to Group II (P < 0.05). There was no statistically significant difference between Groups IV and V. Conclusions: Microleakage increased significantly after external bleaching with 35% hydrogen peroxide, and decreased when the bleached teeth were treated with antioxidants. Ten percent bromelain enzyme was effective in decreasing microleakage; however, its efficacy was similar to 10% sodium ascorbate.

Background: The purpose of this study was to compare the outcome of direct pulp capping by statins with α-tricalcium phosphate (α-TCP) and mineral trioxide aggregate (MTA) on pulp tissue of human teeth through histological evaluation. Aims: The aim of the present study is to compare the pulpal response of statins (simvastatin or atorvastatin) with α-TCP to that of MTA on human teeth by light microscopic histological evaluation. Materials and Methods: Ninety intact premolar teeth scheduled for orthodontic extraction were used for the study. Class 1 cavities were prepared, and the pulp was mechanically exposed under rubber dam isolation. The samples were divided into three groups of thirty teeth each (Group I – simvastatin + α-TCP, Group II – atorvastatin + α-TCP, and Group III – MTA), and the test materials were placed accordingly. After the experimental periods of 7, 30, and 90 days, the teeth were extracted atraumatically. The samples were then evaluated for the degree of inflammation, tissue damage, and hard tissue formation under light microscope, and they were scored based on the histopathologic findings. Statistical Analysis: The results were analyzed statistically using the Chi-square test. Results: There was no statistically significant difference between Groups I, II, and III in terms of inflammation, tissue damage, and hard tissue formation for all the three observation periods (P > 0.05). Conclusions: Simvastatin and atorvastatin with α-TCP were found to be effective in inducing dentin bridge formation which was comparable to MTA.

Aim: The aim of this study was to evaluate the cyclic fatigue resistance of Reciproc (RCP) and RPC Blue (RCPB) instruments used in continuous rotation, “RECIPROC” mode, and “WAVEONE” mode. Materials and Methods: Sixty RCP and 60 RCPB R25 files were used. For each file type, three groups (n = 20) were defined depending on the used kinematics: continuous rotation, “RECIPROC” mode, and “WAVEONE” mode. A stainless-steel artificial canal with 60° angle and 5-mm radius of curvature was milled reproducing the size and taper of the used files. The test device was electrically heated to 35°C to simulate the clinical environment. All files were reciprocated or rotated until fracture. The time to failure and the length of the fractured fragments were measured. A fractographic examination was performed by scanning the electron microscopy to confirm the cause of fracture. Collected data underwent a two-way analysis of variance (α = 0.05). Results: RCPB files exhibited better cyclic fatigue resistance than RCP. The “RECIPROC” motion yielded greater cyclic fatigue resistance than the “WAVEONE” movement; the least resistance was observed in the continuous rotation groups. No significant differences were found among groups in terms of length of the fractured fragment. The fractographic analysis confirmed that all scanned samples separated due to cyclic fatigue. Conclusions: Within the limitation of the present study, the “RECIPROC” mode increased the cyclic fatigue resistance of the tested instruments compared to “WAVEONE” mode and continuous rotation. To prevent RCP and RCPB file separation, motion kinematics other than the native “RECIPROC” movement should be discouraged in the clinical setting.

Aim: The present in vitro study was undertaken to check the effect of the different irrigating solutions with surfactants, i.e., sodium hypochlorite-(Naocl)-Extra, chlorhexidine (CHX)-Ultra, ethylenediaminetetraacetic acid (EDTA), QMix, and BioPure MTAD on the microhardness and smear layer removal of root canal dentin. Materials and Methods: A total of 120 straight rooted lower premolars were collected and were randomly divided into 2 equal groups of 60 each (n = 60). The microhardness of the samples was evaluated by Vickers hardness tester and the removal of smear layer by scanning electron microscope after irrigation of the samples with the tested solutions. Results: CHX-Ultra showed the least microhardness reduction, and EDTA showed the maximum microhardness reduction in all the tested groups. BioPure MTAD showed the maximum removal of smear layer in the apical third, and CHX-Ultra showed the minimal smear layer removal in the apical third. Conclusion: During smear layer removal, irrigating solutions cause alterations in the chemical composition of dentin, which may decrease the microhardness of the root dentin causing erosion and affecting the clinical performance of the endodontically treated teeth. Irrigating solution with maximum smear layer removal with minimum changes in microhardness should be used.

Aim: The study was aimed to evaluate the effect of 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) Solutions on Surface Topography of ESX, TruShape, and ProTaper Gold nickel-titanium (NiTi) Rotary Instruments using Atomic Force Microscope (AFM). Materials and Methodology: A total of 27 each of three commercially available brands of endodontic NiTi instruments were analyzed, which were divided into three groups as follows: Group I: ESX (Brasseler, USA) Group II: Tru shape (Dentsply Tulsa, USA) Group III: Pro Taper Gold (Dentsply Tulsa, USA). These files were further divided into three subgroups containing nine files each, no immersion, immersion in 5.25% NaOCl for 5 min, and immersion in 17% EDTA for 5 min. Surface areas along 3 mm sections at the tip of the files (perfect squares of 10 μm × 10 μm) were analyzed using AFM operating in contact mode under ambient conditions. Statistical Analysis: Data were analyzed using two-way ANOVA and pairwise comparison of three main groups with respect to Ra and RMS by Tukey's multiple posthoc procedures. Results: Three-dimensional AFM images of the surface of all the rotary NiTi instruments, including new and those immersed in 5.25% NaOCl and 17% EDTA solutions, revealed topographic irregularities at the nanometric scale. Ra and RMS values of instruments treated with 5.25% NaOCl and 17% EDTA solutions were statistically higher than that of the new ones (P < 0.05). Conclusion: Using AFM for analysis indicated that short-term contact between 5.25% NaOCl and 17% EDTA solutions and NiTi instruments caused alterations in the topography of instruments.

Aims: The aim of this study is to evaluate and compare the surface deformation and cyclic fatigue resistance of Hyflex controlled memory (CM) and Hyflex electric discharge machining (EDM) files following instrumentation and heat sterilization. Subjects and Methods: Thirty Hyflex CM and thirty Hyflex EDM files were selected and profilometric images taken. Sixty extracted molars were decoronated, cleaning and shaping done with files, and subjected to autoclaving. Profilometric images were taken after instrumentation and sterilization. Cyclic fatigue testing was done at 30° and 60° in a custom-made jig. Statistical Analysis Used: The Mann–Whitney test was used to compare profilometer and cyclic fatigue values between Hyflex CM and Hyflex EDM groups, whereas Friedman's and Wilcoxon signed-rank test were used for intragroup comparisons. Results: Intact Hyflex EDM files showed higher surface roughness values compared to Hyflex CM. Hyflex CM showed an increase in surface roughness after instrumentation and sterilization that was statistically significant while Hyflex EDM showed no statistical significance both after instrumentation and sterilization. Hyflex EDM showed a significantly higher mean number of cycles to failure than Hyflex CM at both degrees. Conclusions: Hyflex EDM files are able to maintain their surface topography and also have cyclic fatigue resistance better than Hyflex CM after both instrumentation and sterilization.

Background: An ideal dental repair material should possess certain important properties such as adequate adhesive ability, insolubility, dimensional stability, biocompatibility, and bioactivity. Newer materials claiming better performance are continuously being introduced in the market to optimize the care of dental patients. Aim: The aim of this study was to evaluate the shear bond strength of three different universal adhesives to OrthoMTA. Materials and Methods: Sixty-four specimens of OrthoMTA measuring 4 mm internal diameter and 2 mm height were prepared and divided into two main groups. After 12 min, 32 samples were randomly selected and divided into four subgroups of eight samples each. Subgroup-I: Single Bond Universal, Subgroup-II: Prime-and-Bond NT, Subgroup-III: Palfique Universal bond, Subgroup-IV: Control. After the application of adhesives, the composite resin was applied using a cylindrical plastic matrix of 2 mm internal diameter and 2 mm height over OrthoMTA. This procedure was repeated 24 h after mixing an additional 32 samples, respectively. Shear bond strengths were measured using Universal testing machine and fractured specimen were examined under stereomicroscope. Data were statistically analyzed using a two-way ANOVA test and Tukey's multiple post hoc test. Results: Statistical analysis revealed that subgroup-III exhibited higher bond strength at both 12 min and 24 h time intervals. It was also observed that most of the failures occurred cohesively within OrthoMTA. Conclusion: Shear bond strength was higher at 24 h than compared to 12 min. Subgroup-III exhibited higher bond strength than other subgroups.

Aim: This study aims to evaluate the effect of three endodontic chelating agents (17% ethylenediamine tetra-acetic acid [EDTA], 1% peracetic acid [PAA], 0.2% Chitosan) on the push out bond strength of gutta percha with a new bioceramic sealer (BioRoot RCS). Materials and Methods: Forty-eight single-rooted mandibular premolars were selected and decoronated to obtain standardized root length of 15 mm. The root canals were prepared up to #30 files (Hyflex CM) and copious irrigation was done with 3 ml of 5.25% of NaOCl. According to the final irrigation, specimens were divided into three groups: Group 1 (n = 16) 0.2% chitosan, Group 2 (n = 16) 17% EDTA, and Group 3 (n = 16) 1% PAA for 1 min. Samples from each group were obturated with bioceramic sealer and gutta percha and sealed with temporary filling material. Two horizontal slices of 2 mm was obtained from the middle third of each sample (n = 32). Push out bond strength and failure modes were assessed. Kruskal–Wallis test followed by Mann–Whitney post hoc analysis was used for push out analysis. Chi square test was used to compare the modes of failure. The statistical significance level was set at P = 0.05. Results: The highest push out bond strength was obtained with Group 1 (0.2% chitosan) followed by Group 3 (1% PAA). Group 2 (17% EDTA) showed least push out bond strength when compared to Group 1 (0.2% chitosan) and Group 3 (1% PAA). The mode of failure was mainly cohesive for all groups. Conclusions: The highest push-out bond strength of BioRoot RCS was seen after treatment with 0.2% chitosan while the least was after EDTA treatment. 1% PAA treatment also favorably affected push-out bond strength of BioRoot RCS.

Aim: The main aim of the study is to compare the antibacterial effect of Silver nanoparticle gel alone and combination of silver nanoparticle gel with various medicaments. Materials and Methods: Intracanal dressings: Group 1 –Silver Nanocure gel, Group 2 - Silver Nanocure gel+ Cavisept gel(1:1),Group 3- Silver Nanocure gel+ Aveu-Cal gel(1:1) ,Group 4 – Silver Nanocure gel +Cavisept gel +Aveu-Cal gel(1:1:1) were taken on a culture plate inoculated with E.faecalis. Antibacterial activity was assessed using Agar diffusion test and results were noted as diameter of growth inhibition zone. Statistical Analysis: Student t –test was used to analyse results. Results: The diameter of combination of Silver nanocure gel+Cavisept +Aveu-Cal gel(1:1:1) was highest in comparison to other medicaments tested. Conclusion: Intracanal dressing with a combination of all the three {Silver nanocure gel+Cavisept +Aveu-Cal gel(1:1:1) } is the best treatment for elimination of highly resistant Enterococcus faecalis in root canals.

Objectives: The objective is to evaluate the effect of collagen stabilizing agents-chitosan and proanthocyanidin (PA) on the shear bond strength to dentin and microleakage of resin composite at enamel and cemental walls. Materials and Methods: Thirty premolars were decoronated 2 mm above cemento-enamel junction and restored with composite resin. Teeth were then randomly divided into three groups: Group I - Control, Group II - Pre-treatment with chitosan, and Group III - Pre-treatment with PA. Samples were then subjected to thermocycling for 500 cycles at 5°C and 55°C with the dwell time of 30 s and transfer time of 5–10 s. Then, the samples were subjected to shear bond strength evaluation on Universal testing machine. Shear load was applied until failure occurred. The load to failure was recorded individually and statistical analysis was done. Microleakage was determined by methylene blue dye penetration method and subjected to stereomicroscopic evaluation. Statistical analysis was carried out using Mann–Whitney test and Chi-square test. Results: Group II specimens produced the highest median shear bond strength and group I showed the least. In addition, Group I, Group II, and Group III showed no statistically significant difference in microleakage. Conclusions: Application of Chitosan and PA improved the shear bond strength to dentin as compared to the control. However, no significant difference in shear bond strength and microleakage was found between them.

Objective: Zinc oxide eugenol (ZOE) is one of the most commonly used root canal sealer. However, it has few drawbacks such as cytotoxicity, solubility, and irritation to periapical tissues. The scope of this study was to investigate the setting time, solubility, cytotoxic effects, and anti-inflammatory action of ZOE sealer with the modification of its liquid component by the addition of petasin extract in the ratios 1:1, 5:1, and 10:1. Materials and Methods: Setting time was evaluated using the Vicat's apparatus. For testing solubility, the American Dental Association's specification #8 was adopted with certain modifications. Protein denaturation assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay with L929 mouse fibroblast cell lines were used to evaluate the anti-inflammatory property and cytotoxicity, respectively. Results: ZOE sealer with petasin extract in the ratio of 5:1 showed the least initial and the final setting times. There was no statistically significant difference in the amount of solubility for all the groups at the various time intervals. The cytotoxicity of the control group was significantly greater than all the experimental groups, whereas the anti-inflammatory effect of the former was statistically lower. Conclusions: The combination of ZOE with petasin extract in the ratio of 5:1 showed lower setting time, cytotoxicity, and better anti-inflammatory property.

Aim: This study aims to evaluate and compare the sealing ability of Biodentine™ and mineral trioxide aggregate (MTA) plus^® on root end cavities treated with 17% ethylene diamine tetraacetic acid (EDTA), 0.2% Chitosan and 1% Phytic acid using Confocal Laser Scanning Microscope (CLSM)-An in vitro study. Materials and Methods: Sixty extracted single rooted teeth were instrumented and obturated with gutta-percha. The apical 3 mm of each tooth was resected and 3 mm root-end preparation was made using ultrasonic tip. 17% EDTA (n = 20), 0.2% Chitosan (n = 20) and 1% Phytic acid (n = 20) was used as a smear layer removing agent and each above group was further subdivided and restored with a root end filling material, Biodentine (n = 10) and MTA Plus (n = 10). The samples were coated with varnish except at the root end and after drying, they were immersed in Rhodamine B dye for 24 h. The teeth were then rinsed, sectioned longitudinally, and observed under CLSM. Results: In the present study, MTA Plus® treated with 1% Phytic acid showed the least microleakage followed by Biodentine™ treated with 1% Phytic acid which was statistically not significant. MTA Plus^® treated with 17% EDTA showed the highest microleakage when compared to other tested groups. There was a significant difference in microleakage between MTA Plus® and Biodentine™ when treated with 17% EDTA and 0.2% Chitosan. However, more microleakage was seen with Biodentine™ group than MTA plus® group. Conclusion: Root end cavities restored with MTA plus and treated with Phyitc acid showed superior sealing ability. Furthermore, smear layer removing agents will aid in better adaptability of root end filling material.

External root resorption of permanent teeth is a multifactorial process. This article presents an unusual case of localized idiopathic extensive external root resorption involving the whole mesial root of the right mandibular first molar in a 42-year-old female patient. No significant systemic, dental, or familial findings could be identified as a possible cause. The cause of the resorption remained unclear. The tooth was managed by nonsurgical endodontic treatment using mineral trioxide aggregate to seal resorbed canals. A 5-year follow-up revealed satisfactory results clinically and radiographically with mobility within physiological limits.

Dens invaginatus (DI) is one of the rare malformations of teeth which results from an infolding of the dental papilla during the development of teeth. This defect gives rise to a possible communication between the pulp and oral environment, thereby increasing the susceptibility to caries, pulpitis, and pulp necrosis. Thus, early detection and conservative management of this invaginatus is of utmost importance. The present case series describes a conservative endodontic treatment technique for the management of teeth with Type II DI using a guided endodontic approach with three-dimensional printed surgical stents. This technique provides a precise and minimally invasive approach in the conservative management of DI, without compromising the vitality of main pulpal tissue.