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Soil ecosystems harbor diverse microorganisms and yet remain only partially characterized as neither single-cell sequencing nor whole-community sequencing offers a complete picture of these complex communities. Thus, the genetic and metabolic potential of this "uncultivated majority" remains underexplored. To address these challenges, we applied a pooled-cell-sorting-based mini-metagenomics approach and compared the results to bulk metagenomics. Informatic binning of these data produced 200 mini-metagenome assembled genomes (sorted-MAGs) and 29 bulk metagenome assembled genomes (MAGs). The sorted and bulk MAGs increased the known phylogenetic diversity of soil taxa by 7.2% with respect to the Joint Genome Institute IMG/M database and showed clade-specific sequence recruitment patterns across diverse terrestrial soil metagenomes. Additionally, sorted-MAGs expanded the rare biosphere not captured through MAGs from bulk sequences, exemplified through phylogenetic and functional analyses of members of the phylum Bacteroidetes Analysis of 67 Bacteroidetes sorted-MAGs showed conserved patterns of carbon metabolism across four clades. These results indicate that mini-metagenomics enables genome-resolved investigation of predicted metabolism and demonstrates the utility of combining metagenomics methods to tap into the diversity of heterogeneous microbial assemblages.IMPORTANCE Microbial ecologists have historically used cultivation-based approaches as well as amplicon sequencing and shotgun metagenomics to characterize microbial diversity in soil. However, challenges persist in the study of microbial diversity, including the recalcitrance of the majority of microorganisms to laboratory cultivation and limited sequence assembly from highly complex samples. The uncultivated majority thus remains a reservoir of untapped genetic diversity. To address some of the challenges associated with bulk metagenomics as well as low throughput of single-cell genomics, we applied flow cytometry-enabled mini-metagenomics to capture expanded microbial diversity from forest soil and compare it to soil bulk metagenomics. Our resulting data from this pooled-cell sorting approach combined with bulk metagenomics revealed increased phylogenetic diversity through novel soil taxa and rare biosphere members. In-depth analysis of genomes within the highly represented Bacteroidetes phylum provided insights into conserved and clade-specific patterns of carbon metabolism.

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AIM: The aim was to compare and evaluate the efficacy of electrochemically activated water (ECA) against maleic acid, Mixture of tetracycline, acid and detergent. ie; 3% doxycycline, 4.25% citric acid, and 0.5% Tween 80 detergent (MTAD), Sodium hypochlorite (NaOCl), and saline as root canal irrigants in removing the smear layer. MATERIALS AND METHODS: Twenty single canal mandibular premolars were randomly divided into five groups (n = 4), decoronated, prepared to working length, and instrumented till F3 using protaper gold rotary files. Each group was assigned a different irrigant. Saline-negative control and NaOCl-positive control. Teeth were sectioned and subjected to Scanning Electron Microscopic analysis. ECA was prepared using a custom-made apparatus having two chambers of capacity 50 ml each separated by a polymer membrane. About 40 ml of tap water was collected in each chamber. Two graphite electrodes were connected to the top of the compartments, linked to a power supply which initiates electrolysis, and the solutions obtained in anodic and cathodic compartments were collected. Statistical analysis was done using one-way ANOVA and Post hoc Tukey analysis. RESULTS: NaOCl, maleic acid, and ECA had similar smear layer removal efficacy. MTAD was less efficient than the other irrigants tested. Saline did not remove the smear layer. CONCLUSION: Electrochemically activated water has promising smear layer removal efficacy and is comparable with conventional root canal irrigants.

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BACKGROUND: Pain and discomfort due to untreated dental caries lead to eating and sleep disruptions, behavioral changes, and poor quality of life. Among adolescents, severe dental caries may lead to activity restriction, school absenteeism, and poor academic performance. Dietary factors, parent's socioeconomic status, and family income have been associated with dental caries experience. The employment status of the mother is a measure of socioeconomic status of the family. AIMS: This study aims to estimate the prevalence of dental caries and to find out its sociodemographic, oral health behavioral, and clinical determinants among older adolescent (15-18 years) students in Kerala. SETTINGS AND DESIGN: This was a cross-sectional study conducted at higher secondary schools. METHODS: Oral examination and sociodemographic and oral health behavioral data collection were done among 1065 older adolescent students in the age group 15-18 across five districts of Kerala by a multistage cluster sampling design. Decayed, missing, and filled teeth (DMFT) and Significant Caries (SiC) index were taken. STATISTICAL ANALYSIS USED: SPSS version 16 software was employed. Multiple regression analysis was done to estimate adjusted odds ratios (OR) of predictors of dental caries experience. RESULTS: The overall dental caries experience for the group was 59.8% (95% confidence interval [CI]: 56.9-62.7). About 40% of students had no caries experience, 43% had DMFT score 1-3, and only 16.8% had DMFT score 4 and more. Mean DMFT was 1.67 (95% CI: 1.56-1.79). Diet preference, timing of sugar intake, and sugar form were not significantly associated with caries. Mean SiC index was 3.90 (95% CI, 3.75-4.05). In the unadjusted analysis, age, gender, place of residence, mother's employment status, school type, frequency of sugar intake, oral hygiene status, and timing of last dental visit were significant. In the adjusted analysis, however, age, male gender, government schools, timing of last dental visit, and employed mothers were significant predictors for higher dental caries experience. CONCLUSIONS: Mother's employment was the strongest predictor (OR 2.82, 95% CI: 2.15-3.69) for dental caries experience among adolescents when adjusted to other variables in the final multivariate model.

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INTRODUCTION: Patient Reported Outcomes (PROs) are now regarded as a fundamental measure of therapeutic success. Patient's opinion regarding the impact of disease and its treatment is assessed using scales such as Oral Health Related Quality Of Life (OHRQoL) tools. Patient centred outcome assessment is now being considered as a primary outcome measure in clinical trials. AIM: To evaluate whether treatment of periodontal disease could influence OHRQoL based on available literature. MATERIALS AND METHODS: An electronic search was done in Google, Google Scholar and Pubmed for articles in English language using the terms Quality of Life or ORHQoL or PROs or patient centered outcome and periodontal therapy. The search commenced on 1st September 2016 and ended on 15th December 2016. Studies that employed one or more than one multi-item OHRQoL instrument to assess PROs related to either non-surgical or surgical periodontal therapy were reviewed. RESULTS: Initially 423 relevant articles were obtained, from which based on screening titles and abstracts 396 were excluded. Full text of remaining 27 articles were retrieved. Nineteen clinical studies with 1345 participants and 2 systematic reviews were included after the full text review. CONCLUSION: Both surgical and Non-surgical Periodontal Therapy (NSPT) significantly influenced the OHRQoL scores. However the change in scores after surgical therapy when compared to nonsurgical therapy was not statistically significant. There is a need for a specific PROs scale that could potentially tap the entire dimension of the change in patients' perception brought about by periodontal therapy.

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The use of psychometric tools to assess various psychological aspects of malocclusion and treatment is increasing in orthodontics. Mere evaluation of an orthodontic patient with normative criteria is not enough; instead, the psychological status should be assessed using a questionnaire. Many generic and few condition-specific tools are available for assessing quality of life (QoL) in orthodontics. The steps involved in the development of such tools are complex and unknown to many. This article outlines the methodology involved in the development and validation of a psychometric tool for dental and orthodontic use. It also helps the clinician to translate and cross-culturally adapt an existing QoL tool to a different setting.

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The recognition of health related quality of life began ever since WHO expanded the definition of health in 1948. This has resulted in the paradigm shift of health and disease from a medical model to a biopsychosocial model. Oral health too denotes not merely the absence of disease but the general well being so that the person can perform functions like eating, talking and smiling and also can contribute creatively to the society. Health related quality of life is a trade-off between how long and how well people live. To explain the concept various theoretical models have been proposed, of which the conceptual model of Wilson and Cleary 1995 is a comprehensive one. Even after much research and thousands of publications the definition of oral health related quality of life is still vague. But the patient's self perception about his oral health and related life quality are significant in clinical dental practice, dental education and research. It is widely shown that oral conditions can have varied impacts on daily living. To assess this, many measures or scales are available. They differ depending on the response format, number of items, context of use and the population in which it is applied. Patient reported outcome assessment is a less developed area in clinical dentistry and research and in future it has the potential to become the primary or secondary outcome measure in clinical interventional research.

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AIMS: The purpose of this study was to evaluate the resistance to torsional failure and cyclic fatigue resistance of ProTaper Next (PTN), WaveOne, and Mtwo files in continuous and reciprocating motion. SETTINGS AND DESIGN: Randomized control trial in a tertiary care setting. SUBJECTS AND METHODS: A total of 10 new size 25.06 taper PTN X2, 25.06 taper Mtwo files, and 25.08 taper WaveOne primary files each was selected. A custom fabricated cyclic fatigue testing device with a 70° angle of curvature and 3 mm width; curvature starting at 6 mm from the tip was used. All instruments were rotated and reciprocated till fracture occurred and time till fracture of each instrument was recorded in seconds. For torsional failure testing 5 mm tip of each file was embedded in composite resin block and uniform torsional stresses (300 rpm, 2.0 Ncm) were applied repetitively by an endodontic motor with auto stop mode until file succumbed to torsional failure. Number of load applications leading to failure was recorded. STATISTICAL ANALYSIS USED: Data were analyzed using t-test for equality of means, Pearson correlation, and ANOVA test. RESULTS: All the files showed superior resistance to cyclic fatigue in reciprocating motion when compared with continuous rotation mode. WaveOne primary files displayed maximum resistance to cyclic fatigue both in continuous and reciprocating motion. WaveOne primary files also demonstrated maximum resistance to torsional failure followed by PTN with Mtwo files exhibiting least resistance. CONCLUSIONS: Operating files in reciprocating motion enhances their cyclic fatigue resistance. WaveOne files showed maximum resistance to cyclic fatigue and torsional failure due to their cross-sectional diameter coupled M-Wire technology.

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BACKGROUND: Calcium phosphate cements (CPC) are a group of biomaterials possessing wide scope of use in various branches of medical science. These materials have been proposed to be highly biocompatible and osteoconductive. This study is based on a newly developed CPC formulation (Chitra-CPC) and is aimed at the evaluation of its biocompatibility through an Endodontic Usage Test in a porcine study model. OBJECTIVE: To evaluate the periapical tissue reaction to Chitra-CPC when used as a root canal sealer/filler material in comparison with a resin sealer, AH Plus (Dentsply). MATERIALS AND METHODS: The procedure was done on porcine animal model following the ISO 7405 criteria. The material was implanted intentionally into the periapical area of 36 teeth through a root canal procedure carried out in six animals which were divided equally among 1-month and 3-month time periods. Results were based on the histological evaluation of the autopsied specimens after the prescribed time periods. RESULTS: Mild to moderate periapical tissue reaction was found in Chitra-CPC samples belonging to the 1-month time period, whereas majority of the 3-month CPC samples showed an absence of inflammation. Samples of AH Plus in 1-month period showed severe to moderate inflammation, whereas 3-month AH Plus samples had a mild to moderate inflammation. CONCLUSIONS: Chitra-CPC is a biocompatible material.

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When a tooth fracture occurs, the fracture line can extend in a variety of directions, and the direction of the fracture line often dictates the treatment plan. In cases where fracture lines extend apical to the gingival margin, exposure of fractured margins becomes necessary. And management of such tooth fractures often requires an interdisciplinary approach involving endodontic, periodontic and restorative procedures. This article describes a case in which severely traumatized maxillary anterior teeth were managed by a combined approach involving surgical exposure and crown lengthening, endodontic and restorative procedures.

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AIM: This in vitro study was conducted on enamel blocks of human premolars with the aim of evaluating the remineralization potential of fluoride and ACP-CPP and the combination of ACP-CPP and fluoride on early enamel lesions. MATERIALS AND METHODS: Fifteen intact carious free human premolars were selected. The coronal part of each tooth was sectioned into four parts to make 4 enamel blocks. The baseline SMH (surface microhardness) was measured for all the enamel specimens using Vickers microhardness (VHN) testing machine. Artificial enamel carious lesions were created by inserting the specimens in demineralization solution for 3 consecutive days. The SMH of the demineralised specimens was evaluated. Then the four enamel sections of each tooth were subjected to various surface treatments, i.e. Group 1- Fluoride varnish, Group 2- ACP-CPP cream, Group 3- Fluoride + ACP-CPP & Group 4- Control (No surface treatment). A caries progression test (pH cycling) was carried out, which consisted of alternative demineralization (3hours) and remineralization with artificial saliva (21 hours) for five consecutive days. After pH cycling again SMH of each specimen was assessed to evaluate the remineralization potential of each surface treatment agent. Then, to asses the remineralization potential of various surface treatments at the subsurface level, each enamel specimen was longitudinally sectioned through the centre to expose the subsurface enamel area. Cross-sectional microhardness (CSMH) was evaluated to assess any subsurface remineralization RESULTS: Statistical analysis using one-way ANOVA followed by multiple comparisons test was applied to detect significant differences at P

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Measurement of platelet adhesion in vitro is a good indicator of its reactivity to implant devices in vivo. Platelets were labeled with I-125 without affecting its normal morphology and function and the labeled platelets were suspended in platelet poor plasma and exposed to Ti and diamond like carbon-coated (DLC) Ti discs, under dynamic conditions, using a parallel plate flow chamber. The test materials were washed, dried, exposed to a phosphor screen and scanned to get the images. The number of platelets that adhered to Ti was found to be higher than those that adhered to DLC coated Ti sample, irrespective of the shear stress which was varied between 2 and 16 dynes/cm(2).

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During a 48 month period to December 1990, 367 patients, median age 75 years, with obstructive jaundice caused by common bile duct stones (201), malignant biliary obstruction (148), and benign biliary strictures (18), underwent therapeutic endoscopic retrograde cholangiopancreatography. Endoscopic biliary stenting and drainage was achieved in 343 of 367 patients attempted (93%), seven patients requiring a combined percutaneous endoscopic approach. Endoscopic stenting failed in 24 patients because of malignant duodenal infiltration (10), Billroth 2 gastrectomy (6), tight and extensive biliary strictures (6), peripapillary diverticulum (1), and technical failure (1). Prolonged follow up was available in 91% (311 of 343). The 30 day mortality was 5% (17 of 343), which included two procedure related deaths (0.6%) from fulminant pancreatitis and major sphincterotomy site bleeding. Early complications occurred in 14% (48 of 343) and late complications occurred in 11.9% (35 of 294) patients, as of the original 343, 17 had died within 30 days and another 32 were lost to follow up. Eighty patients with incomplete bile duct clearance and eight patients with benign biliary strictures had biliary stents inserted for 12-48 months (median 30). Endoscopic biliary stenting services are necessary in a district general hospital with technical success, death and morbidity rates comparable to other studies.

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AIMS: To investigate a female patient with a tumour mass of the terminal ileum, to define the nature of the tumour, and to correlate its morphology and behaviour with similar types of tumours of the large intestine and stomach. METHODS: Tissues obtained at colonoscopy, from hemicolectomy specimens, and from liver and peritoneal biopsy specimens were studied macroscopically, microscopically, histochemically, and immunohistochemically for epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA), neuron specific enolase (NSE), and S100 protein. RESULTS: Macroscopic examination showed a tumour of the terminal ileum protruding into the caecum. Microscopically the tumour showed two components, one adenoma with moderate dysplasia and the other carcinoid tumour. The adenomatous component stained positively for EMA and CEA and negatively for NSE. The carcinoid component stained positively for NSE and negatively for EMA and CEA. Histochemically the carcinoid area was argyrophil positive and argentaffin negative. Only the carcinoid had metastasised, to the liver, peritoneum, and the lymph nodes, at the time of diagnosis. CONCLUSION: The morphological, histochemical, and immunohistochemical findings confirm the diagnosis of a composite adenoma-carcinoid tumour of the terminal ileum.

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