Comparative Evaluation of the Bonding Efficacy of Multimode Adhesive, Two-Step Self-Etch Adhesive, and a Total-Etch System to Pulpal Floor Dentin - An In vitro Study.

Background: Postendodontic restoration with composite resins has gained popularity due to the development of more reliable adhesives with simplified bonding procedures and less technique sensitivity. Pulpal floor dentin is a complex biological structure and a more challenging bonding substrate. Hence, appropriate selection of the bonding agent for these regions of the tooth is important. Aims: To compare the shear bond strength of a new generation of dental adhesives referred to as multimode adhesives, two-step self-etch adhesive, and a total-etch system to pulpal floor dentin. Materials and Methods: Sixty human mandibular molars were sectioned with a slow speed diamond disc to expose the pulp chamber and divided into four groups of 15 teeth each, based on the bonding agent used. Group A: Single bond universal (self-etch); Group B: Single Bond Universal (etch-and-rinse), Group C: Clearfil SE Bond, Group D: Adper Single Bond 2. Using a split Teflon mold, composite cylinders were built on the prepared dentinal surfaces. The shear bond strength was then evaluated with the universal testing machine. Results: Two step self-etch adhesives recorded higher shear bond strength than total-etch and multimode/universal adhesives applied in both self-etch and etch-and-rinse techniques. Conclusion: The self-etching/priming system bonded more strongly to the pulpal floor dentin than multimode adhesive and total-etch system.

Evaluation of Sealing Potential of Different Repair Materials in Furcation Perforations Using Dye Penetration: An In Vitro Study.

AIM: The present study aimed to assess the sealing ability of various repair materials in furcation perforations using dye penetration. MATERIALS AND METHODS: A total of 80 human first molars from mandible with unbroken enamel surfaces, which were extracted completely for periodontal reasons, were chosen. All extracted teeth were kept in a sterile solution up until further use. Endo-access bur was used to prepare endodontic access cavity, and a high-speed long shank round bur was used to create a planned perforation on the floor of pulp. All the specimens were randomly grouped (20 teeth in each group): Group I: control; group II: Pro-Root MTA; group III: resin-modified glass-ionomer cement (RM GIC); and group IV: Biodentin. After placement of repair materials in perforated furcation, the chamber of each tooth was accessed with 2% methylene blue dye. Later, a diamond disk was used to split the teeth buccolingually. A stereomicroscope (10×) was used to visualize the highest dye penetration. RESULTS: The least penetration was seen in teeth repaired by Biodentin group (0.88 ± 0.02), next by Pro-Root MTA group (1.24 ± 0.13) and resin-modified glass ionomer cement group (3.62 ± 0.46). A statistically significant difference was seen among different perforation repair materials by analysis of variance. A statistically significant difference (p value < 0.05) was found between each group, excluding group II v/s group IV. CONCLUSION: This study concluded that reduced dye penetration in perforation repair along the furcations and improved sealing ability are shown by biodentine group in comparison to Pro-Root MTA and resin-modified glass-ionomer cement group. CLINICAL SIGNIFICANCE: Root perforations along the furcation that develop due to the endodontic procedures have a remarkable damaging effect on prognosis and frequently result in loss of secondary periodontal attachment, thus resulting in early loss of the involved tooth. Therefore, the selection of biocompatible repair material aids to enhance the treatment prognosis.

Clinical Assessment of Gingival Sulcus Width using Various Gingival Displacement Materials.

AIM: This study aims to compare the clinical efficacy of three different gingival retraction systems on gingival sulcus width. MATERIALS AND METHODS: Study was conducted on prepared right or left maxillary central incisor for 45 subjects. Totally, 15 patients were randomly allocated in three gingival displacement groups, i.e., group I (retraction cord impregnated with aluminum chloride), group II (magic foam), and group III (laser). The pre- and postdisplacement impressions were made with addition silicone material using two-stage double mix technique. RESULTS: There was no difference between the groups at baseline. Group III produced more displacement (mean value 0.48 ± 0.101 mm) than group II (mean value 0.31 ± 0.09 mm) and group I (mean value 0.44 ± 0.11 mm), and this was statistically significant. CONCLUSION: Laser gingival displacement system was found to be effective among the three retraction systems. Choice of gingival displacement system is based on clinical situation and choice of operator. CLINICAL SIGNIFICANCE: The retraction groups in the study created greater amount of gingival retraction than the least sulcus width required for the elastomeric impression material and so are clinically useful.

Impact of Mouthwashes on Antibacterial Activity of Subjects with Fixed Orthodontic Appliances: A Randomized Clinical Trial.

AIM: The study aimed to assess the impact of mouthwashes on antibacterial activity of individuals with fixed orthodontic appliances. MATERIALS AND METHODS: A total of 60 individuals were considered in the study. Sixty (20 each group) nonextraction class I individuals were randomly divided into experimental and control groups. Group I: Experimental group [chlorhexidine (CHX) mouthwash], group II: Experimental group (neem mouthwash), group III: Control group (distilled water). All the clinical examinations were done at baseline and 30th day respectively, after the start of orthodontic treatment. The mean differences between the different experimental groups were calculated using one-way analysis of variance (ANOVA) test. RESULTS: There was no statistical significance at baseline mean plaque index (PI), gingival index (GI) scores, and Streptococcus mutans (SM) colony count between groups. The PI and GI scores among CHX and neem mouthwash groups (p = 0.002, p = 0.032 respectively) were significantly reduced after intervention and also the SM colonies count was reduced in CHX and neem mouthwash groups and there was significant difference between the groups. CONCLUSION: As both mouthwashes showed significant effectiveness on antibacterial activity in individuals with fixed orthodontic appliances, neem mouthwash can be used as an alternative to CHX. CLINICAL SIGNIFICANCE: It is better to have a sound knowledge regarding the use of mouthwash in long term as fixed orthodontics are associated with accumulation of SM, enamel demineralization, and an increased number of carious lesions, predominantly in sites adjacent to bracket.

PRmePRed: A protein arginine methylation prediction tool.

Protein methylation is an important Post-Translational Modification (PTMs) of proteins. Arginine methylation carries out and regulates several important biological functions, including gene regulation and signal transduction. Experimental identification of arginine methylation site is a daunting task as it is costly as well as time and labour intensive. Hence reliable prediction tools play an important task in rapid screening and identification of possible methylation sites in proteomes. Our preliminary assessment using the available prediction methods on collected data yielded unimpressive results. This motivated us to perform a comprehensive data analysis and appraisal of features relevant in the context of biological significance, that led to the development of a prediction tool PRmePRed with better performance. The PRmePRed perform reasonably well with an accuracy of 84.10%, 82.38% sensitivity, 83.77% specificity, and Matthew's correlation coefficient of 66.20% in 10-fold cross-validation. PRmePRed is freely available at http://bioinfo.icgeb.res.in/PRmePRed/.

Proteomic Identification and Analysis of Arginine-Methylated Proteins of Plasmodium falciparum at Asexual Blood Stages.

Plasmodium falciparum undergoes a tightly regulated developmental process in human erythrocytes, and recent studies suggest an important regulatory role of post-translational modifications (PTMs). As compared with Plasmodium phosphoproteome, little is known about other PTMs in the parasite. In the present study, we performed a global analysis of asexual blood stages of Plasmodium falciparum to identify arginine-methylated proteins. Using two different methyl arginine-specific antibodies, we immunoprecipitated the arginine-methylated proteins from the stage-specific parasite lysates and identified 843 putative arginine-methylated proteins by LC-MS/MS. Motif analysis of the protein sequences unveiled that the methylation sites are associated with the previously known methylation motifs such as GRx/RGx, RxG, GxxR, or WxxxR. We identified Plasmodium homologues of known arginine-methylated proteins in trypanosomes, yeast, and human. Hydrophilic interaction liquid chromatography (HILIC) was performed on the immunoprecipitates from the trophozoite stage to enrich arginine-methylated peptides. Mass spectrometry analysis of immunoprecipitated and HILIC fractions identified 55 arginine-methylated peptides having 62 methylated arginine sites. Functional classification revealed that the arginine-methylated proteins are involved in RNA metabolism, protein synthesis, intracellular protein trafficking, proteolysis, protein folding, chromatin organization, hemoglobin metabolic process, and several other functions. Summarily, the findings suggest that protein methylation of arginine residues is a widespread phenomenon in Plasmodium, and the PTM may play an important regulatory role in a diverse set of biological pathways, including host-pathogen interactions.

Bacterial Biofilm Removal Using Static and Passive Ultrasonic Irrigation.

BACKGROUND: The aim of the present study was to evaluate the efficiency of two irrigating techniques - static and dynamic (passive ultrasonic instrumentation) irrigation in the elimination of bacterial biofilm. MATERIALS AND METHODS: Forty extracted human permanent maxillary central incisors teeth with straight roots and single canals, were randomly allocated to two groups for static irrigation and passive ultrasonic irrigation (PUI). The root canal irrigant used was 2.5 % sodium hypochlorite. The root canals were prepared to tip sizes (20, 40) and tapers (0.04, 0.08). Using system GT instruments (Dentsply Malliefer, Switerzland). The teeth were split longitudinally into two, stained collagen was applied to the canal surfaces and the tooth reassembled for static and PUI. Digital images of the canal surface were taken before and after irrigation with 9, 18, 27 and 37 mL solution. The digital images were analyzed using ImageJ software (National Institute of Health, USA) to quantify residual canal coverage by the stained collagen. The data were analyzed using linear regression models and subjected to statistical analysis. RESULTS: The mean percentage of canal surface with residual collagen increased with the coronal level of canal, decrease in apical size and taper of canal preparation and decrease in the volume of the irrigant. There was less residual collagen after PUI compared with static irrigation. The canal surface facing the open side port of the needle had less residual collagen after irrigation than the opposing surface. CONCLUSION: The stained collagen biomolecular film could not be removed completely either by passive ultrasonic instrumentation or static irrigation. The PUI was found to be more effective in the removal of collagen, especially in the apical part of the root canal.