Is Deep margin elevation a reliable tool for cervical margin relocation? - A comparative review.

The permanence of deep subgingival restorations are questionable both functionally and biologically. Crown lengthening is one of the traditionally performing procedures to visualize and relocate the deep margins, but the limitations of the invasive surgical procedure are anatomical complications like exposure of root concavities or furcation, violation of biological width, post operative discomfort because of sutures or periodontal packs; and less patient compliance. Other than crown lengthening, researchers tried some other techniques like modified matrix adaptation technique, using retraction cord, making holes in matrix band and flowing resin modified glass ionomer cement (RMGIC) to the root or cervical caries, orthodontic extrusion. But most of these procedures are failed to give adequate clinical success. Deep margin elevation (DME) is one of the minimally invasive and successful procedure performing in deep subgingival caries. But the evidences and knowledge in this technique is limited among practitioners. This review is to evaluate the applicability of DME, the current clinical concepts, techniques and materials for DME; and a comparison with traditionally used various techniques for cervical margin relocation also concluding that currently available various clinical parameters with this technique.

Evaluation of the Efficacy of Recent Caries Removal Techniques: An In Vitro Study.

INTRODUCTION: Dentistry is undergoing a gentle revolution that will consign drill and fill to history. In order to increase the acceptance of dental treatment, efforts are directed toward changing traditional painful dentistry into a new concept of painless dentistry. It is common practice to utilize burs for caries removal and cavity preparation. Chemomechanical caries removal is a painless procedure that uses a chemical substance to eradicate diseased dentine. With the Food and Drug Administration (FDA) approval of Erbium-doped yttrium-aluminum-garnet (Er: YAG) laser systems for caries removal and cavity preparation, the discipline of laser operational dentistry was born out of a desire to find a way to remove the decay without causing any pain or stress to the surrounding healthy tissue. AIM AND OBJECTIVES: This in vitro research aimed to assess the relative advantages of chemomechanical and laser caries extraction techniques in comparison to the more traditional bur technique. The efficacy of each method was evaluated by microscopic examination of samples treated with each experimental method. We also evaluated the efficiency of each method by recording the time required for caries excavation. MATERIAL AND METHODS: The methods used for caries excavation were bur excavation, chemo-mechanical method, and laser method. Histological slices were produced after all the samples had been treated with the experimental techniques, and they were studied using a binocular light transmission microscope. The samples were then scored as '0' for absence and '1' for the presence of demineralized dentine. These scores and the time recorded for each method were subjected to statistical analysis. RESULTS: This study found no statistically significant difference in the effectiveness of the different approaches to removing caries; however, bur excavation was the quickest and chemo-mechanical was the slowest, with the latter not being useful in cases with low caries activity. The laser method of caries removal doesn't remove caries existing in the undercut areas of the cavity thus making the use of bur mandatory. CONCLUSION: With more practice and experience, the chemo-mechanical and laser methods can be used in a more efficient way to render painless operative procedures to patients.

Evaluating the Effect of Different Intra-Orifice Barriers and Various Bleaching Agents on the Fracture Resistance of Teeth After the Walking Bleach Procedure: An In Vitro Study.

Objective This study aimed to evaluate the effect of three different commercially available intra-orifice barriers and bleaching agents on root canal-treated teeth. Materials and methods Forty-five freshly extracted single-rooted incisors, canine, and premolars were collected and stored in 10% formalin. Root canal procedures were performed on the extracted teeth and these were classified into three groups and three subgroups (n=5). Group 1: resin-modified glass ionomer cement (RMGIC); placed at the level of cemento-enamel junction (CEJ) and cured for 20 seconds. Group 2: BiodentinTM (Septodont Ltd., Saint Maur des Fausse´s, France); powder and liquid were mixed according to the manufacturer's instructions and placed at the level of CEJ, and waited for 15 minutes to set. Group 3: bulk-fill composite; placed at the level of CEJ. Group A was treated with 35% carbamide peroxide (Ultradent Opalescence 35% PF regular). Group B was bleached with 35% hydrogen peroxide (Pola Office). Group C, which was the control group, was treated with distilled water. The bleaching procedure was repeated once every seven days for a period of three weeks. After bleaching, every sample was sectioned 2 mm above the level of CEJ to remove the crown. Auniversal testing machine (UTM) was used for the evaluation of the fracture resistance of teeth. Data were analyzed for significance by using analysis of variance (ANOVA) and further pair-wise comparison was performed by pos-hoc analysis. The level of significance was set at p<0.05 Results There was a significant difference between the fracture resistance of the three materials when bleached using distilled water (p<0.05). The fracture resistance of Group 3 was significantly greater than that of Group 2 and Group 1 (p<0.05). The difference in the fracture resistance between Group 1 and Group 2 was nonsignificant (p>0.05). Conclusion Walking bleach performed via bleaching agents 35% carbamide peroxide and 35% hydrogen peroxide leads to a reduction in the fracture resistance of endodontically treated teeth; 35% hydrogen peroxide causes more fracture resistance reduction than carbamide peroxide of the same concentration. The presence of intra-orifice barriers leads to greater fracture resistance and reinforcement of endodontically treated teeth that undergo the walking bleach procedure. Bulk-fill composite can be used as an intra-orifice barrier with good fracture resistance.

Reinforcing an immature tooth model using three different restorative materials.

Background: To compare and evaluate the strength rendering capacity of three restorative materials in tooth model simulated as immature teeth. Materials and Methods: In this in vitro study, 80 human maxillary permanent central incisors scheduled for periodontal extraction were collected, and an immature tooth model was prepared using a 3 mm twist drill. To simulate single-visit apical barrier, all the teeth were prepared with peso number 1-6. The teeth were segregated into three experimental and a control group. The experimental groups (n = 20) comprised of fiber-reinforced composite (FRC), Biodentine, and glass ionomer cement. The fracture resistance of all the teeth was tested using universal testing machine. The final reading of the applied load to cause fracture was noted and later was subjected to statistical analysis, P ≤ 0.05 was considered statistically significant, and the level of significance was fixed at 5%. Student's t-test was applied to compare values among experimental groups. Results: There was a significant difference in the values of peak load resulting in fracture among experimental groups which was observed statistically (P ≤ 0.001). FRC exhibited superior reinforcing capacity (mean: 1199.7 N) among the experimental materials followed by Biodentine and Bioglass R. The lowest value to fracture was observed in control group (mean: 236.7 N). Conclusion: The results indicate that FRC could substantially contribute positively in reinforcing the simulated thin-walled immature roots.

The Study of Prevalence and Distribution of Shape Anomalies of Teeth in Indian Population on the Basis of Age and Gender.

INTRODUCTION: Dental anomaly of shape leads to various clinical dental pathologies requiring the intervention of a dental specialist. Early diagnosis and intervention in earlier stages can restore a near-normal dentition and esthetics. So, the present study was undertaken to determine the prevailing dental anomalies of shape and its various subtypes in various age groups and gender variations. MATERIALS AND METHODS: Retrospective dental casts and radiographs were evaluated in 3,000 cases consisting of an equal proportion of males and females. Only cases with an age range from 10 to 40 years were included in the study. Dental anomalies of shape were evaluated for the presence of Gemination, fusion, talon cusp, dens evaginates, the cusp of carabelli, dens invaginatus, taurodontism, and dilacerations and recorded. RESULT: A total of 538 (17.9%) cases were found to have dental anomalies of shape which included 288 (19.2%) males and 250 (16.6%) females. Dilaceration was found to be the most common (9.2%) dental anomaly of shape followed successively by taurodontism (3.7%), talon cusp (2.23%), and the cusp of carabelli (1.4%). Most of the shape anomalies showed male predilection. A higher prevalence of most dental anomalies of shape was found in the younger age group of 10 to ≤25 years as it is not linked with age but still has got importance to know while the treatment is carried out in this age group. CONCLUSION: It is quite imperative to have complete knowledge of trends and patterns of shape anomalies in India. It will guide dental practitioners to formulate a treatment plan on the basis of existing prevailing anomalies.

No-Tillage with Residue Retention and Foliar Sulphur Nutrition Enhances Productivity, Mineral Biofortification and Crude Protein in Rainfed Pearl Millet under Typic Haplustepts: Elucidating the Responses Imposed on an Eight-Year Long-Term Experiment.

Yield limitation and widespread sulphur (S) deficiency in pearl-millet-nurturing dryland soils has emerged as a serious threat to crop productivity and quality. Among diverse pathways to tackle moisture and nutrient stress in rainfed ecologies, conservation agriculture (CA) and foliar nutrition have the greatest potential due to their economic and environmentally friendly nature. Therefore, to understand ammonium thiosulphate (ATS)-mediated foliar S nutrition effects on yield, protein content, mineral biofortification, and sulphur economy of rainfed pearl millet under diverse crop establishment systems, a field study was undertaken. The results highlighted that pearl millet grain and protein yield was significantly higher under no-tillage +3 t/ha crop residue mulching (NTCRM) as compared to no-tillage without mulch (NoTill) and conventional tillage (ConvTill), whereas the stover yield under NTCRM and ConvTill remained at par. Likewise, grain and stover yield in foliar S application using ATS 10 mL/L_twice was 19.5% and 13.2% greater over no S application. The sulphur management strategy of foliar-applied ATS 10 mL/L_twice resulted in significant improvement in grain protein content, protein yield, micronutrient fortification, and net returns (₹ 54.6 × 1000) over the control. Overall, ATS-mediated foliar S nutrition can be an alternate pathway to S management in pearl millet for yield enhancement, micronutrient biofortification and grain protein content increase under ConvTill, as well as under the new NTCRM systems.

Cognizance and Use of Minimally Invasive Dentistry Approach by General Dentists: An Overlooked Companion.

BACKGROUND: Dental caries begins with the decalcification of the first nonorganic part, followed by the decay of the organic tooth matrix. Minimally invasive dentistry (MID) focuses on using the adhesive technique for restoration as these techniques allow minimum removal of healthy tooth structure. OBJECTIVE: This study aimed to assess the attitude, knowledge, and behavior of the general dentists toward the use of MID and to evaluate if MID is considered as standard care measure among general dentists. MATERIALS AND METHODS: This was a cross-section observational survey and included 285 practicing dentists. The survey questions were divided into two parts. The question related to the use of sharp explorer utilized response categories (1-5), with options of always, most of the time, often, sometimes, and never or rarely. The independent variables collected were age, gender, years of practice, clinical hours, type of practice, postgraduate education, and clinic environment. The data collected were tabulated and were statistically analyzed. RESULTS: The results of the present study showed that MID meets the standard of care for the treatment of both primary teeth 85.96% (n = 245) as well as permanent teeth 78.24% (n = 223). ART, sandwich technique, in-office, and at-home topical fluoride application were considered active for treating dental caries. The use of sharp explorers, nonsharp explorers, radiographs, and magnification were considered common for caries detection. CONCLUSION: The more dentists who listened to about MID in the past responded that the MID concept is the standard of care for the treatment of primary and permanent teeth than dentists who have heard little or nothing about MID.

Comparison of Efficacy of Various Intracanal Irrigants with Ultrasonic Bypass System.

BACKGROUND: The long-term success of root canal therapy depends on the effective debridement and removal of smear layer and debris from the canal. Root canals with difficult anatomy and complex systems pose great challenge to achieve this. Mechanical therapy alone cannot achieve this goal, various intracanal chemicals also have their own limitations along with the difficulty in reaching the farfetched and difficult areas, and hence, introduction of ultrasonic bypass system has been a boon for the endodontic therapy. OBJECTIVES: The aim of this study is to compare the various root canal medicaments along with ultrasonic bypass system in effectively cleaning the debris and smear layer from the various parts of the root canal system. MATERIALS AND METHODS: Forty single-rooted anterior maxillary and mandibular human teeth were collected for this study, after disinfection, they were sectioned into three equal parts coronal, middle, and apical and these parts were later studies under SEM (Scanning Electron Microscope) and scoring as per the scoring criteria set before the study was done and results were then compared statistically. RESULTS: Group with both ethylenediaminetetraacetic acid (EDTA) and NaOCl with ultrasonic bypass system was the most effective one, when compared with sterile water, NaOCl + ultrasonic bypass system, EDTA + ultrasonic bypass system. NaOCl + ultrasonic bypass system was more effective as compared with the EDTA + ultrasonic bypass system. CONCLUSION: Ultrasonic bypass system is a useful tool for debris and smear layer removal from a root canal system, but its effectiveness increases when both EDTA and NaOCl are used along with it.

Comparison of antimicrobial efficacy of aqueous ozone, green tea, and normal saline as irrigants in pulpectomy procedures of primary teeth.

AIM: Sodium hypochlorite, though considered an ideal root canal irrigant, cannot be used at required concentrations in children, due to its undesirable effects. Hence, it is imperative to search for an ideal root canal irrigant to avoid these undesirable effects which we hope to achieve with this study. The antimicrobial efficacy of aqueous ozone, green tea, and normal saline as irrigants in pulpectomy procedures of the primary teeth has been compared. MATERIALS AND METHODS: Sixty patients between 4 and 8 years of age with a single-rooted deciduous tooth indicated for pulpectomy were included. The infected teeth were randomly allocated to one of the three treatment groups based on the irrigating agents used, namely normal saline, green tea extract, or ozonated water. Specimens for anaerobic culture were collected three times from the teeth: before irrigation, after initial irrigation, and on the 3rd day after final irrigation. RESULTS AND CONCLUSION: Mean colony forming unit (CFU) count after both initial and final irrigation with ozonated water was significantly lower when compared with green tea and normal saline. Further, it was observed that the mean CFU count with green tea was significantly lower than the counts obtained with normal saline on the 3rd day after final irrigation. Hence, both ozonated water and green tea could be considered a good alternative to conventional root canal irrigants in the primary teeth. Larger sample sizes with a larger variety of irrigants are recommended.

Immediate Placement, Immediate Loading of Single Implant in Fresh Extraction Socket.

Smile is an important factor which enhances our beauty. A well-formed complete smile is the basis for facial esthetics. To bring out a beautiful smile, a full set of dentition is necessary. The replacement of missing teeth with implant-borne restorations has become the treatment of choice these days. According to recent reports, the successful implant placement in fresh extraction socket is made possible by modifying the surface of implants. The present case report highlights on the high survival rate of immediate implant loading placed successfully in fresh extraction socket which was confirmed by implant stability quotient (resonance frequency analysis) to assess implant stability noninvasively.

Bio-fortification potential of global wild annual lentil core collection.

Lentil, generally known as poor man's' meat due to its high protein value is also a good source of dietary fiber, antioxidants and vitamins along with fast cooking characteristics. It could be used globally as a staple food crop to eradicate hidden hunger, if this nutritionally rich crop is further enriched with essential minerals. This requires identification of essential mineral rich germplasm. So, in the present study, a core set of 96 wild accessions extracted from 405 global wild annual collections comprising different species was analyzed to determine its bio-fortification potential. Impressive variation (mg/100 g) was observed for different minerals including Na (30-318), K (138.29-1578), P (37.50-593.75), Ca (4.74-188.75), Mg (15-159), Fe (2.82-14.12), Zn (1.29-12.62), Cu (0.5-7.12), Mn (1.22-9.99), Mo (1.02-11.89), Ni (0.16-3.49), Pb (0.01-0.58), Cd (0-0.03), Co (0-0.63) and As (0-0.02). Hierarchical clustering revealed high intra- and inter-specific variability. Further, correlation study showed positive significant association among minerals and between minerals including agro-morphological traits. Accessions representation from Turkey and Syria had maximum variability for different minerals. Diversity analysis exhibited wide geographical variations across gene-pool in core set. Potential use of the identified trait-specific genetic resources could be initial genetic material, for genetic base broadening and biofortification of cultivated lentil.

Additive-free thick graphene film as an anode material for flexible lithium-ion batteries.

This work demonstrates a simple route to develop mechanically flexible electrodes for Li-ion batteries (LIBs) that are usable as lightweight effective conducting networks for both cathodes and anodes. Removing electrochemically dead elements, such as binders, conducting agents and metallic current collectors, from the battery components will allow remarkable progress in this area. To investigate the feasibility of using thick, additive-free graphene films as anodes for flexible LIBs, we have synthesized and tested thick, additive-free, freestanding graphene films as anodes, first in a coin cell and further in a flexible full cell. As an anode material in a half cell, it showed a discharge capacity of about 350 mA h g(-1) and maintained nearly this capacity over 50 cycles at various current rates. This film was also tested as an anode material in a full cell with a LiCoO2 cathode and showed good electrochemical performance. Because the graphene-based flexible film showed good performance in half- and full coin cells, we used this film as a flexible anode for flexible LIBs. No conducting agent or binder was used in the anode side, which helped in realizing the flexible LIBs. Using this, we demonstrate a thin, lightweight and flexible lithium ion battery with good electrochemical performance in both its flat and bent states.

Highly conductive freestanding graphene films as anode current collectors for flexible lithium-ion batteries.

The electrodes in lithium-ion batteries (LIBs) are typically films that are arranged on metal foil current collectors with a thickness of several tens of µm. Here, we report on the preparation of a thick free-standing graphene film synthesized by CVD as an alternative to Cu foil as an anode current collector. As a model system, MoS2 anodes with a flower-like morphology were anchored onto the surface of the thick graphene film. A hybrid and binder free anode without a conventional metal current collector exhibited an excellent capacity value of around 580 mAh/g (@50 mA/g) and reasonable charge/discharge cyclability. The work presented here may stimulate the use of graphene films as replacements for conventional current collectors and additive free electrode in LIBs.

Evaluating sanitization of toothbrushes using ultra violet rays and 0.2% chlorhexidine solution: A comparative clinical study.

BACKGROUND: Toothbrushes may play a significant role in plaque control. Toothbrushes should be correctly stored, disinfected and changed at regular intervals. OBJECTIVE: The purpose of this study was to evaluate the efficacy of 0.2% chlorhexidine (CHX) gluconate solution and ultra violet (UV) toothbrush-sanitizer for toothbrush disinfection. MATERIALS AND METHODS: Fresh tooth brushes were distributed to fifteen study subjects, who were selected randomly and who met the study criteria. All the study participants were asked to brush their teeth with the tooth brush provided. No special instructions were given regarding the brushing techniques. Toothbrushes were collected after 7 days. All tooth brushes were randomly allocated to three groups. Tooth brushes were subjected to microbial analysis and total bacterial count was assessed. Tooth brushes allocated to Group I were soaked in 2% CHX mouthwash for 12 h, Group II were kept in UV-light toothbrush holder for 7 min, and Group III were soaked in normal saline for 12 h. All the toothbrushes were subjected for microbial analysis and mean bacterial count was determined. RESULTS: There was a statistically significant difference between mean colony-forming unit count pre-sanitization and post-sanitization in all the groups, using 0.2% CHX gluconate, UV rays and normal saline (P < 0.007). However, the mean bacterial count reduced drastically after the treatment with UV rays (P = 0.001). CONCLUSIONS: CHX, UV rays and normal saline are effective in a reduction of bacterial count on toothbrushes. UV rays treatment was more effective, when compared to CHX and normal saline.

Graphene Films for Flexible Organic and Energy Storage Devices.

Graphene and its derivatives have been the subject of extensive research in fundamental science and have viable applications in current and future technology. The exceptionally high electronic and thermal conductivity, optical transparency, and high specific surface area, combined with excellent mechanical flexibility and environmental stability leave graphene poised to be a material of the future. This perspective introduces the importance of graphene electrodes, discusses the synthesis of graphene and transfer onto desired substrates and the role of graphene in electrodes for a broad range of flexible devices such as photovoltaic, electronic, and electrochemical energy storage.

Simultaneous growth of self-patterned carbon nanotube forests with dual height scales.

In this study, we report on a unique, one-step fabrication technique enabling the simultaneous synthesis of vertically aligned multi-walled carbon nanotubes (VA-MWCNTs) with dual height scales through alcohol catalyzed chemical vapor deposition (ACCVD). Regions of VA-MWCNTs with different heights were well separated from each other leading to a self-patterning on the surface. We devised a unique layer-by-layer process for application of catalyst and inhibitor precursors on oxidized Si (100) surfaces before the ACCVD step to achieve a hierarchical arrangement. Patterning could be controlled by adjusting the molarity and application sequence of precursors. Contact angle measurements on these self-patterned surfaces indicated that manipulation of these hierarchical arrays resulted in a wide range of hydrophobic behavior changing from that of a sticky rose petal to a lotus leaf.