Comparative evaluation of the effect of ultrasonic and rotary agitation of herbal irrigating solutions on smear layer: A SEM study.

Context: Instrumentation and irrigation balance helps in effective removal of endodontic microbes housing inside the smear layer. Aim: This study aimed to (1) evaluate whether activation of the irrigating solutions with two different systems during the final irrigation step can lead to smear layer formation in the middle and apical third of the root canal and (2) evaluate and compare the smear layer removal ability of the aqueous extracts of Emblica officinalis and Morinda citrifolia. Materials and Methods: A total of 72 single-rooted teeth were prepared up to F4 ProTaper. The specimens were assigned into eight groups of nine teeth each, according to the final irrigant and activation techniques. Further, the teeth were evaluated under SEM for endodontic smear layer at the middle and apical third. Statistical Analysis: Inferential statistics included Pearson's Chi-square. Level of significance was set at 0.05 at 95% confidence level. Results: Ultrasonic activation system showed significant (P = 0.000) amount of smear layer compared to XP-Endo Finisher file. A significant difference (P = 0.00) in the smear layer removal was observed when 6% M. citrifolia was activated with XP-Endo Finisher file both in the middle and apical third. Conclusion: Within the limitations of this in vitro study, it can be concluded that smear layer formation was noted with ultrasonic and XP-Endo Finisher file when saline was used as an irrigant. 6% M. citrifolia when activated with XP-Endo Finisher file showed best results among all other experimental groups.

An in vitro evaluation of effectiveness of Xylene, Thyme oil and Orange oil in dissolving three different endodontic sealers.

Aims: The aim of the study is to compare the dissolution effectiveness of xylene, thyme oil, and orange oil on three different endodontic sealers. Materials and Methods: Standardized stainless steel molds were used to prepare 210 samples (70 for each endodontic sealer). The samples were divided into three groups based on sealers. Three experimental groups with 20 samples each were immersed in organic solvents. One control group of 10 samples was immersed in distilled water. Each group was further subdivided into two subgroups based on immersion time (2 and 10 min). Inferential statistics included one-way ANOVA, post hoc Tukey, and paired t-test. Results: Thyme showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer whereas this difference was nonsignificant for Roekoseal and MTA Fillapex. Orange oil showed significantly more dissolution at 10 min compared to 2 min in dissolving AH Plus sealer and Roekoseal whereas this difference was nonsignificant concerning MTA Fillapex. Xylene showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer, Roekoseal, and MTA Fillapex. Conclusions: Among the three solvents, xylene showed the highest dissolution of all three sealers. Orange oil was superior to thyme oil in dissolving the sealers. All the sealers showed more dissolution in all the solvents at 10 min compared to 2 min.

Coffee pulp: From a by-product of coffee production to a potential anticariogenic mouth rinse! An in vivo study.

Background and Objectives: Dental caries is a prevalent disease despite various efforts made toward its prevention. The drawbacks of the available preventive agents have led to the quest for a potentially more effective agent with fewer adverse effects. Coffee, a local produce of Coorg, is one such herbal alternative. This study aims to assess the potential antimicrobial activity of Robusta coffee pulp extracts on Streptococcus mutans. Methodology: A total of 39 participants were divided into three groups with 13 participants each, after obtaining ethical clearance and informed consent: Group A (negative control), sterile water; Group B (positive control), 0.2% chlorhexidine mouth rinse; and Group C, 2.5% coffee pulp extract rinse (prepared according to minimum inhibitory concentration). The saliva samples were collected from the patients in a sterile Eppendorf tube at prerinse for baseline, at 1-h postrinse, and at the end of 2 weeks. The S. mutans colony count was done using image-based software analysis. The acquired data were statistically analyzed with one-way ANOVA and repeated measures ANOVA followed by post hoc Tukey's test. Results: Coffee pulp mouth rinse (P = 0.035) and positive control (P = 0.036) groups showed a statistically significant reduction in the microbial count at 2 weeks postrinse (compared to the negative control group). Conclusion and Clinical Relevance: The coffee pulp extract-based mouth rinse is a potential anticariogenic agent that offers few advantages over chlorhexidine as no instances of staining, altered taste, or any allergic reactions were reported by the subjects.

Evaluation of Root Dentinal Damage Associated with ProTaper Gold, WaveOne Gold, and ProTaper Next during Cleaning and Shaping Procedures: An In vitro Analysis.

AIM: The purpose of this study is to evaluate and compare the incidence of dentinal defects after root canal shaping using rotary nickel-titanium (Ni-Ti) instruments (ProTaper Gold [PTG] and ProTaper Next [PTN]) and reciprocating instrument (WaveOne Gold [WOG]). MATERIALS AND METHODS: One hundred human mandibular premolars with single root and single canal with canal curvature <10° were randomly divided into five groups (n = 20 teeth per group). The root canals were instrumented using hand K-files (positive control), full sequence rotary files PTG and PTN, and reciprocating single-file system WOG. One group was left unprepared and served as negative control. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a stereomicroscope. RESULTS: PTG, WOG, and PTN showed dentinal defects in 40%, 53.3%and 30% of the samples, respectively. CONCLUSION: Irrespective of motion kinematics, dentinal defects are observed in all the Ni-Ti file groups. Within the limitations of the present study and the available literature, incidence of dentinal defects is less with instruments working in continuous rotation rather than instruments with reciprocating motion.

Comparative evaluation of remineralizing potential of commercially available agents MI paste, Remin pro, and Clinpro using Scanning Electron Microscope and Energy Dispersive X-ray: An in vitro study.

BACKGROUND: According to recent approaches, the prevention of initial dental caries is achieved using certain noninvasive methods. One such method is the topical application of remineralizing agents. Various remineralizing products are commercially available, but their efficacy is uncertain. AIM: The aim of the study was to evaluate the remineralizing potential of MI, Reminpro, and Clinpro using scanning electron microscope (SEM) and energy dispersive X-ray (EDX). METHODOLOGY: Forty extracted human premolars were collected. The samples were decoronated and the crown portion was coated with nail varnish leaving behind a 3 mm × 3 mm window on the labial surface. The samples were soaked in demineralizing solution for 4 days to create an artificial lesion, followed by SEM-EDX analysis. The samples were then randomly divided into 4 groups Control, MI, Remin Pro, and Clinpro with ten samples each. The remineralizing agents were applied according to the group and subjected to pH cycling for 21 days which was followed by SEM-EDX analysis. Data obtained were statistically analyzed using SPSS IBM version 23 (ANOVA, post hoc-Tukey, and Paired-t-test). RESULTS: Ca and P were increased after remineralization in all groups. Between groups, the increase was more for ReminPro, followed by Clinpro and MI. CONCLUSION: In this study, the remineralizing potential of Remin Pro was effectively more, followed by Clinpro and MI.

Comparison of the Root End Sealing Ability of Four Different Retrograde Filling Materials in Teeth with Root Apices Resected at Different Angles - An Invitro Study.

INTRODUCTION: Insufficient apical seal is the significant reason for surgical endodontic disappointment. The root-end filling material utilized should avoid egress of potential contaminants into periapical tissue. AIM: The aim of this study was to compare the sealing ability of four root-end filling materials MTA, Portland cement, IRM, RMGIC in teeth with root apices resected at 0 and 45 angle using dye penetration method under fluorescent microscope. MATERIALS AND METHODS: Hundred extracted human maxillary anterior teeth were sectioned horizontally at the cement-enamel junction. After cleaning, shaping and obturation with gutta-percha and AH Plus sealer, the tooth samples were randomly divided in two groups (the root apices resected at 0° and 45° to the long axis of the root). The root resections were carried out by removing 2 mm and 1 mm in both the groups. Following which 3 mm deep root-end cavities were prepared at the apices and the root were coated with nail varnish except the tip. The teeth in both the group were randomly divided into four subgroups each (Pro root MTA, Portland cement, IRM and Light cure nano GIC Ketac N-100). All the retrofilled samples were stored in acrydine orange for 24 hours after which they were cleaned and vertically sectioned buccolingually. The sectioned root samples were observed under fluorescent microscope. RESULTS: The root apex sealing ability of Mineral Trioxide Aggregate (MTA) was superior to Portland cement, Intermediate Restorative Material (IRM) and LC GIC. IRM demonstrated the maximum apical leakage value among all the materials. Portland cement and LC GIC showed comparable sealing ability. CONCLUSION: The angulation whether 0° or 45° angle did not affect the sealing ability of all the four materials used, MTA proved to be one of the superior materials for root-end filling.

Effect of 10% Sodium Ascorbate on Shear Bond Strength of Bleached Teeth - An in-vitro Study.

BACKGROUND: Patient often requires some additional interventions such as replacement of old restorations, laminates and veneers after bleaching, for aesthetic purposes. The residual oxygen inhibits polymerization of resin based materials which results in reduced bond strength of the restorations. Some techniques are available to solve the clinical problems related to the post bleach compromised bond strength. OBJECTIVES: The purpose of this study is to evaluate, the role of 10% sodium ascorbate on reversing the compromised bond strength and compare enamel shear bond strength of 5th and 6th generation dentine bonding agents on bleached and unbleached teeth. MATERIALS AND METHODS: Eighty freshly extracted human anterior teeth were assigned in to Group A and Group B of 40 teeth each. Samples in both groups were subdivided in to 4 subgroups of 10 teeth each. In Group A composite resins was bonded using 5th generation dentine bonding agent (3M Single Bond) and Group B was bonded using 6th generation (3M ESPE Adper SE Plus). Subgroups were subjected to the procedure as, A1;B1 etching and bonding (control), A2; B2 bleaching, etching and immediate bonding, A3; B3 bleaching,10% ascorbic acid treatment for 10 minutes after that etching and bonding immediately, A4; B4 bleaching, storage in artificial saliva for 4 days and then etching and bonding. Pola office, in office bleach (SDI (082216) was used for bleaching. The specimens were subjected to shear load in a Universal testing machine to evaluate bond strength. RESULTS: A decrease in bond strength was seen with 6th generation adhesive system compared to 5th generation bonding system, which is statistically significant, p<0.001. CONCLUSION: Treating the bleached enamel surfaces when treated with 10% sodium ascorbate, which reverses the compromised bond strength and is a good alternative to delayed bonding.

Sealing ability of three root-end filling materials prepared using an erbium: Yttrium aluminium garnet laser and endosonic tip evaluated by confocal laser scanning microscopy.

AIMS: (1) To compare the sealing ability of mineral trioxide aggregate (MTA), Biodentine, and Chitra-calcium phosphate cement (CPC) when used as root-end filling, evaluated under confocal laser scanning microscope using Rhodamine B dye. (2) To evaluate effect of ultrasonic retroprep tip and an erbium:yttrium aluminium garnet (Er:YAG) laser on the integrity of three different root-end filling materials. MATERIALS AND METHODS: The root canals of 80 extracted 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 (n = 30) and Er:YAG laser (n = 30). MTA, Biodentine, and Chitra-CPC were used to restore 10 teeth each. The samples were coated with varnish and after drying, they were immersed in Rhodamine B dye for 24 h. The teeth were then rinsed, sectioned longitudinally, and observed under confocal laser scanning microscope. STATISTICAL ANALYSIS USED: Data were analyzed using one-way analysis of variance (ANOVA) and a post-hoc Tukey's test at P < 0.05 (R software version 3.1.0). RESULTS: Comparison of microleakage showed maximum peak value of 0.45 mm for Biodentine, 0.85 mm for MTA, and 1.05 mm for Chitra-CPC. The amount of dye penetration was found to be lesser in root ends prepared using Er:YAG laser when compared with ultrasonics, the difference was found to be statistically significant (P < 0.05). CONCLUSIONS: Root-end cavities prepared with Er:YAG laser and restored with Biodentine showed superior sealing ability compared to those prepared with ultrasonics.

An In-Vitro Comparison of Micro Leakage Between Two Posterior Composites Restored with Different Layering Techniques Using Two Different LED Modes.

AIM: Composite resins have undergone various advances since their introduction, but their polymerization shrinkage remains a problem. Shrinkage can cause debonding of the restoration and can contribute to postoperative sensitivity, secondary caries, marginal staining and eventual failure of the restoration. So, our aim is to compare the effect of two different placement techniques and two different curing modes in reducing the marginal microleakage of two different composites in Class II cavities, where oblique and horizontal placement techniques and ramp & pulse curing modes of LED are used during the restoration. MATERIALS AND METHODS: Standardized slot preparations were prepared in 80 human multi-rooted teeth. The teeth were randomly divided into four groups. Group A and B: Restored with Filtek P60 (3M, ESPE), Group C and D: Restored with Filtek P90 (3M, ESPE). All groups were further divided into sub-groups on basis of placement technique and curing mode. The samples were stored in distilled water, followed by thermocycling and immersed in 2% methylene blue. The samples were sectioned and evaluated for microleakage at the gingival margin with an optical stereomicroscope. RESULTS: P60 composite when placed in the cavity with oblique incremental technique and cured with ramp mode of LED showed highest mean microleakage. There is no significant difference between horizontal and oblique placement technique (p=0.80); Pulse-curing and the ramp-curing mode (p=0.62). CONCLUSION: In restoring deep class II cavities, the use of a low-shrink composite with the oblique placement technique and ramp curing mode of LED is recommended to overcome the problem of marginal microleakage.

Management of palato radicular groove in a maxillary lateral incisor.

This study is to report the rare localization of a radicular groove on the palatal aspect of the maxillary lateral incisor and to discuss the pathology and management of the concomitant endo-periodontal defect. Unilateral palato-radicular groove was located on the Maxillary right lateral incisor of an 18-year-old female patient. The groove was associated with deep local periodontal pocket resulting in pulp necrosis and the formation of a large periapical lesion. A collaborative management was carried out using a combination of endodontic therapy, surgical enucleation, odontoplasty, and periodontal regenerative procedure resulting the successful healing of the periapical lesion.

INN-toxin, a highly lethal peptide from the venom of Indian cobra (Naja naja) venom-Isolation, characterization and pharmacological actions.

A novel toxic polypeptide, INN-toxin, is purified from the venom of Naja naja using combination of gel-permeation and ion-exchange chromatography. It has a molecular mass of 6951.6Da as determined by MALDI-TOF/MS and the N-terminal sequence of LKXNKLVPLF. It showed both neurotoxic as well as cytotoxic activities. INN-toxin is lethal to mice with a LD(50) of 1.2mg/kg body weight. IgY raised in chicks against basic peptide pool neutralized the toxicity of INN-toxin. INN-toxin did not inhibit cholinesterase activity. It is toxic to Ehrlich ascites tumor (EAT) cells, but it is not toxic to leukocyte culture. The toxin appears to be specific in its mode of action. Interaction of N-bromosuccinamide (NBS) with the peptide resulted in the modification of tryptophan residues and loss of lethal toxicity of INN-toxin.

Chemistry and structural evaluation of different phospholipase A2 inhibitors in arachidonic acid pathway mediated inflammation and snake venom toxicity.

PLA2 inhibitors specific to Group I and II PLA2 isoforms are therapeutically important as anti-inflammatory molecules and against venom toxicity. From various natural sources diversified molecules with PLA2 inhibition and concomitant neutralization of inflammatory reactions and venom toxicity were characterized. Using these molecules, lead compounds are generated in several laboratories. Analogues of lead molecules were generated by substituting different types of functional groups in order to obtain a molecule with optimal PLA2 inhibition. The lead molecules characterized as PLA2 inhibitors are indoles, azetidinones, piperazines, isoxazolidines, isoxazolines, diazepinones, acenaphthenes and several substrate analogues. The lead optimization involves relative hydrophobicity and substitution of functional groups, such as electron withdrawing or donating. Many such groups are placed on hydrophobic moiety and their positional bioisosters are characterized. Among these analogue piperazine derivatives on optimization with respect to hydrophobicity and electronegativity showed inhibition at nanomolar levels. Structural analysis of many lead molecules indicated that a PLA2 inhibitor should have both hydrophobic moiety and polar functional groups. Each lead molecule requires optimization in this regard for effective inhibition.

Synthesis and efficacy of 1-[bis(4-fluorophenyl)-methyl]piperazine derivatives for acetylcholinesterase inhibition, as a stimulant of central cholinergic neurotransmission in Alzheimer's disease.

The cholinergic hypothesis of Alzheimer's disease (AD) has spurred the development of numerous structural classes of compounds with different pharmacological profile aimed at increasing central cholinergic neurotransmission. Thus proving a symptomatic treatment for this disease are cholinomimetics with the pharmacological profile of acetyl cholinesterase (AchE) inhibitors. The novel bioactive 1-[bis(4-fluorophenyl)-methyl]piperazine derivatives were synthesized under mild conditions using different aryl/alkyl halides and heterocyclic alkyl halides with 1-[bis(4-fluorophenyl)-methyl]piperazine in the presence of powdered potassium carbonate in N,N-dimethylformamide. All the synthesized compounds were characterized by spectroscopic techniques, elemental analysis and were screened for their efficacy as AchE inhibitor. Some derivatives in this class showed good inhibition against AchE as compared to neostigmine as standard.