Objective: The purpose of the study was to examine the substantivity of a new disinfectant against biofilm formation in the dental unit waterlines. Materials and Methods: Twenty dental units were selected for the study and divided into two groups: Group A (dental unit waterlines treated with the disinfectant) and Group B (untreated dental unit waterlines). Biofilm formation was monitored in both groups by removing the one dental unit waterline from each group for the period of 10 days. One inch of the dental unit waterline tube was cut at random site, and the inner lumen of the cut sections was analyzed using the scanning electron microscope (SEM) (TESCAN VEGA3 SBU). Results: On examination, SEM images showed that there was no slime layer or bacterial cells seen in cut section for the period of 7 days in the treated dental waterlines, which means that there is no evident of biofilm formation. In the untreated dental unit waterline cut section, slime layer was observed from day 1. Conclusion: Disinfectant solution was proved to be effective for 7 days against biofilm formation. This technique could be used as a valid method for disinfection of dental unit waterlines.

Context: Being integral to root canal therapy, obturation can be performed adequately only after the removal of intracanal medicament. One technique involves the use of chelating agents such as ethylenediaminetetraacetic acid (EDTA) and citric acid. Etidronic acid, a relatively new chelator, has smear layer removal ability and lesser dentinal erosion. It is untested in calcium hydroxide (Ca[OH]₂) medicament removal. Aim: The aim of this study was to compare the efficiency of irrigation protocols (EDTA, citric acid, and etidronate) in Ca(OH)₂removal. Materials and Methods: Forty-five single-rooted mandibular premolars were decoronated, instrumented, and filled with Ca(OH)₂. After 7 days incubation, Ca(OH)₂was removed by three irrigation protocols (Group-I: 17% EDTA; Group-II: 10% citric acid; and Group-III: 18% etidronate). Roots were split and analyzed (scanning electron microscope, ×1500). Chelator solution pH was tested. Data were analyzed by Kruskal–Wallis ANOVA and Mann–Whitney U-test. Results: Group-III (coronal-third) and Groups-I and II (middle-third) had highest cleanliness scores; Groups-II and III (apical-third) had lowest scores. Comparing the thirds, all groups showed difference in scores. pH of Groups-I, II, and III were 6.8, 1.4, and 0.3, respectively. Conclusion: The solution pH of citric acid and etidronate impacts their Ca(OH)₂removal efficiency in different ways: the highly alkaline pH of Ca(OH)₂increases citric acid pH toward neutrality, where it becomes an inefficient chelator; on the contrary, high acidity of etidronate compensates for its weaker chelation. Etidronate may not require 5 min duration for Ca(OH)₂removal due to the likelihood of dentinal erosion.

Objectives: The aim of this in vitro study was to compare the efficacy of two retreatment rotary systems in the removal of Gutta-percha (GP) and sealer from the root canal walls with or without solvent. Materials and Methods: Forty-eight extracted human mandibular first premolars were prepared and obturated with GP and AH Plus sealer. Samples were then randomly divided into four groups. Group I was retreated with MtwoR rotary system without solvent, Group II was retreated with MtwoR rotary system with Endosolv R as the solvent, Group III with D-RaCe rotary system without solvent, and Group IV with D-RaCe rotary system and Endosolv R solvent. The cleanliness of canal walls was determined by stereomicroscope (×20) and AutoCAD software. Kruskal–Wallis test and Mann–Whitney U-test were used to compare the data. Results: Results showed that none of the retreatment systems used in this study was able to completely remove the root canal filling material. D-RaCe with or without solvent showed significantly (P > 0.05) less filling material at all levels compared to MtwoR with/without solvent. Conclusion: Within the limitation of the current study, D-RaCe rotary retreatment system is more effective in removing filling material from root canal walls when compared to MtwoR rotary retreatment system.

Background: The radiopacity of composite resins has been considered as an important requirement, improving the radiographic diagnosis. Aim: The present study aimed to compare the radiopacity of eight different composite materials using an aluminum step wedge. Materials and Methods: Eight different composite resins were used in this study. The samples were prepared using a stainless steel mold (2 × 8), and a 2-mm-thickness horizontal section was obtained from the freshly extracted molar tooth. Three different radiographs were taken by establishing standard conditions. Mean gray values were obtained by taking three measurements from each step of both the tooth and the aluminum step wedge, and the aluminum thickness equivalents were calculated. Statistical analysis was performed using one-way variance analysis and Tukey's test (P < 0.05). Results: All aluminum thickness equivalents were found to be higher than those of the enamel and dentin, except Clearfil Majesty Esthetic (2.23 mm ± 0.52 mm) and Filtek Silorane (3.67 mm ± 0.15 mm) (P < 0.05). The Clearfil Majesty Posterior (8.50 mm ± 0.10 mm) and Arabesk Top (8.17 mm ± 0.06 mm) were found to be the most radiopaque composites. Conclusion: All composite resin materials tested in this study were confirmed to the International Standards Organization 4049 standards. However, since radiopacity is not the only criterion for clinical use, it is a better approach to take all other properties of the materials into consideration.

Objective: The objective of this study was to evaluate the effect of 8% and 17% ethylenediaminetetraacetic acid (EDTA) exposure for 1 min and 10 min on the fracture resistance of endodontically treated roots. Methodology: Sixty human single-rooted teeth were decoronated and divided into six groups (n = 10). Canal preparation was carried out except in negative control group, using the ProTaper rotary file system. Final irrigation was performed using distilled water, 17% EDTA for 1 min and 10 min, 8% EDTA for 1 min and 10 min. Thereafter, roots were obturated with ProTaper F3 Gutta-percha points and AH Plus sealer using a single-cone technique. The specimens were loaded vertically at 1 mm/min crosshead speed until vertical root fracture occurred. Results were evaluated statistically with one-way analysis of variance and post hoc Tukey test. Results: Analysis of results showed that the unprepared roots showed the highest fracture resistance and roots irrigated with 17% EDTA for 10 min showed the lowest fracture resistance. The mean fracture resistance of unprepared roots, roots irrigated with 8% EDTA for 10 min and 17% EDTA for 1 min was significantly higher than roots irrigated with 8% EDTA for 1 min, 17% EDTA for 10 min and distilled water. Conclusion: From a clinical viewpoint, if EDTA has to be used, it is safer to use higher concentration for a shorter application time or a low concentration with a longer application time. Prolonged use of high concentrations of EDTA might increase the risk of root fracture.

Aim: This study compared the amount of aqueous-based and oil-based calcium hydroxide remaining in the canal, after removal with two different chelators 17% EDTA, 20% Citric acid and 0.2% Chitosan in combination with ultrasonic agitation. Methods and Material: Cleaning and shaping of root canals of 28 mandibular premolar was done and canals were filled either with Metapex or Ca(OH)₂mixed with distilled water. Volumetric analysis was performed utilizing cone beam-computed tomography (CBCT) after seven days of incubation. Ca(OH)₂was removed using either 17% EDTA, 20% Citric acid or 0.2% Chitosan in combination with ultrasonic agitation. Statistical analysis used: Volumetric analysis was repeated and percentage difference was calculated and statistically analyzed using Kruskal-Wallis and Mann-Whitney U test. Results: All the three chelators failed to remove aqueous-based as well as oil-based Ca(OH)₂completely from the root canal. Aqueous-based Ca(OH)₂was easier to be removed than oil-based Ca(OH)₂. 0.2% Chitosan in combination with ultrasonics performed better than 17% EDTA and 20% citric acid in removal of Ca(OH)₂. Conclusion: Combination of 0.2% Chitosan and ultrasonic agitation results in lower amount of Ca(OH)₂remnants than 17% EDTA, 20% Citric acid irrespective of type of vehicle present in the mix.

Background All endodontic instrumentation systems tested so far, promote apical extrusion of debris, which is one of the main causes of postoperative pain, flare ups, and delayed healing. Objectives Of this meta-analysis was to collect and analyze in vitro studies quantifying apically extruded debris while using Hand ProTaper (manual), ProTaper Universal (rotary), Wave One (reciprocating), and self-adjusting file (SAF; vibratory) endodontic instrumentation systems and to determine methods which produced lesser extrusion of debris apically. Methodology An extensive electronic database search was done in PubMed, Scopus, Cochrane, LILACS, and Google Scholar from inception until February 2016 using the key terms “Apical Debris Extrusion, extruded material, and manual/rotary/reciprocating/SAF systems.” A systematic search strategy was followed to extract 12 potential articles from a total of 1352 articles. The overall effect size was calculated from the raw mean difference of weight of apically extruded debris. Results Statistically significant difference was seen in the following comparisons: SAF < Wave One, SAF < Rotary ProTaper. Conclusions Apical extrusion of debris was invariably present in all the instrumentation systems analyzed. SAF system seemed to be periapical tissue friendly as it caused reduced apical extrusion compared to Rotary ProTaper and Wave One.

Objective: The effect of dentin desensitizer Systemp on the shear bond strength of composite resin to dentin using three different bonding agents, i.e., Prime & Bond NT, Xeno V⁺, and Futurabond DC were evaluated. Materials and Methods: Sixty recently extracted human premolars were divided into six groups of ten teeth each. The superficial dentin was etched with 37% phosphoric acid. In Groups I, II, and III, Prime & Bond NT, Xeno V⁺, and Futurabond DC, respectively, were applied to dentin and composite placed. Following application of dentin desensitizer Systemp in Groups IV, V, and VI, Prime & Bond NT, Xeno V⁺, and Futurabond DC, respectively, were applied to dentin and composite placed. The shear bond strength was evaluated. Data obtained were statistically analyzed using one-way analysis of variance, post hoc, and Dunnett's test. Results: Following application of dentin desensitizer Systemp, mean shear bond strength increased when Prime & Bond NT bonding agent was used while it decreased for Xeno V⁺ and Futurabond DC bonding agents. Conclusion: Within the limitations of this in vitro study, it was observed that following application of dentin desensitizer Systemp, mean shear bond strength may increase or decrease depending on the bonding agents used.

Background: Evaluation of the additive effect of photodynamic therapy (PDT) on the antibacterial activity of 2.5% sodium hypochlorite (NaOCl) and QMix against 6-week Enterococcus faecalis biofilms contaminated root canals. Aims: To establish the most suitable irrigant for eradication of 6-week E. faecalis biofilms. Settings and Design: In vitro study. Materials and Methods: A 6-week E.faecalis (ATCC 29212) biofilm was formed in 190 extracted teeth that were subsequently subjected to irrigation protocols as follows. Group A₁: normal saline, Group A₂: 2.5% NaOCl, Group A₃: QMix, Group B₁: normal saline and photoactivated disinfection (PAD), Group B₂: 2.5% NaOCl and PAD, Group B₃: QMix and PAD, Group C: no irrigation. For PAD, irradiation was done three times for 5 s each with 10 s interval on continuous mode with a 980 nm diode laser. Samples from the root canals were collected and plated onto brain heart infusion agar plates to determine the colony-forming unit/ml. Statistical Analysis Used: One-way ANOVA, post hoc Tukey's honest significant difference test. Results: Maximum percentage of disinfection (99%) was seen in Group B₂ (NaOCl with PDT), which was similar to Groups A₂ (97.6%) and B₃ (98.8%) ( P< 0.0001). Conclusions: NaOCl with PDT gave maximum disinfection.

Introduction: Pulp sensitivity testing, even with its limitations and shortcomings, has been and still remains a very helpful aid in endodontic diagnosis. Pulp sensitivity tests extrapolate pulpal health from the sensory response. The aim of the present study was to identify the sensitivity, specificity, positive and negative predictive values (NPVs) of thermal and electrical tests of pulp sensitivity. Materials and Methods: Pulp tests studied were two cold and heat tests respectively and electrical test. A total of 330 teeth were tested: 198 teeth with vital pulp and 132 teeth with necrotic pulps (disease prevalence of 40%). The ideal standard was established by observing bleeding within the pulp chamber. Results: Sensitivity values of the diagnostic tests were 0.89 and 0.94 for cold test, 0.84 and 0.87 for the heat tests, and 0.75 for electrical pulp test and the specificity values of the diagnostic tests were 0.91 and 0.93 for the cold tests, 0.86 and 0.84 for the heat tests, and 0.90 for electrical pulp test. The NPVs were 0.91 and 0.96 for the cold tests, 0.89 and 0.91 for the heat tests, and 0.84 for electrical pulp test. The positive predictive values were 0.89 and 0.90 for the cold tests, 0.80 and 0.79 for the heat tests and 0.88 for electrical pulp test. The highest accuracy (0.9393) was observed with cold test (icy spray). Conclusions: The cold test done with icy spray was the most accurate method for sensitivity testing.

This article aims to report a unique case with aberrant root canal anatomy exhibiting “Y-” and “J”-shaped canal pattern in a mandibular second molar. Anatomic complexities may pose challenges for endodontic treatment. Before performing endodontic treatment, the clinician should be aware of the internal anatomy of the tooth being treated and should recognize anatomic aberrations if present. Presence of unusual anatomy may call for modifications in treatment planning. This report describes in detail about a mandibular second molar tooth associated with two paramolar tubercles having a peculiar “Y-” and “J-”shaped canal anatomy detected with the aid of cone beam computed tomography, which has never been reported in the dental literature. The proposed treatment protocol for the endodontic management of the same has also been discussed.

Dens invaginatus is a relatively common dental malformation resulting from an infolding of enamel organ into the dental papilla varying in depth into the tooth tissues. Complex morphological anatomy associated with the pulpal pathology presents inaccessibility to completely remove the necrotic pulp tissues and hence poses challenges in rendering endodontic treatment. A combination of nonsurgical and surgical management in treating such cases is advisable depending on the presented variations. The present case reports the surgical endodontic treatment of an immature maxillary lateral incisor with type II dens invaginatus and periapical pathology.

Tooth fusion consists of the union of crowns by the enamel and/or dentin. We describe a case of a patient who presented with a fistula in the apical portion of teeth 32 and 33. Clinically, tooth 32 showed increased crown width in relation to other teeth in the same arch. Radiographic examination evidenced fusion of tooth 32 with a possible supernumerary tooth. Cone-beam computed tomography was used to confirm the radiographic findings and revealed incomplete apex formation of the supernumerary tooth. The fused tooth was subjected to root canal treatment. Calcium hydroxide was used as intracanal medication, changed for every 30 days, for 4 months. Subsequently, the mesial canal received an apical plug of mineral trioxide aggregate mixed with distilled water. At 2 years of follow-up, the tooth showed signs of tissue repair.