Effectiveness of a new endodontic irrigation system for removing smear layer and dissolving simulated organic matter.

OBJECTIVES: The study aimed to evaluate the potential for the dissolution of organic tissue in areas of simulated complexity and cleaning of root canal walls of the new iVac® endodontic irrigation system. MATERIAL AND METHODS: Thirty mandibular premolars were evaluated by scanning electron microscopy before and after biomechanical preparation. Then, they were distributed according to the final irrigation protocol into groups with conventional irrigation, ultrasonic agitation with metallic insert (UA), and iVac® system, and new photomicrographs were obtained. For tissue dissolution analysis, glass capillaries filled with catgut were attached to the cervical and apical thirds of twenty-one prototyped upper incisors. They were weighed before and after the previously mentioned irrigation protocols. The data were statistically compared with a significance level of 5%. RESULTS: The final irrigation provided greater cleaning of the root canal walls in the cervical, middle, and apical thirds of the root canals (P < 0.05), with no statistically significant difference between UA and iVac®, regardless of the analyzed thirds. Both ultrasonic irrigation protocols dissolved a significantly greater volume than the conventional irrigation protocol (P < 0.05), with no difference between the two protocols (P < 0.05). CONCLUSIONS: The iVac® system showed root canal wall cleaning and tissue dissolution similar to UA with a metallic insert, and both were superior to conventional irrigation. CLINICAL RELEVANCE: The new irrigation system iVac is more effective than conventional irrigation and has similar root canal wall cleaning and tissue dissolution to UA.

An unusual repair of perforating internal inflammatory root resorption; a case report of endodontic treatment

Internal inflammatory root resorption (IIRR) can occur as a serious complication of dental trauma which leads to progressive loss of the root structure. An early diagnosis could influence the therapeutic approach, but endodontic treatment becomes a challenge with a doubtful prognosis. The present report described an unusual clinical presentation of an IIRR with perforation resulting from a trauma four years previous. A 15-year-old female patient was presented to our service with pain in the maxillary incisor region. Intraoral radiography revealed a large radioloucent area compatible with IIRR, communicating with the periodontium in the middle third on the distal root face of the right central incisor. The root canal of the right central incisor was chemo-mechanically prepared. The calcium hydroxide (CH) intracanal medication was used and renewed periodically four times. The root canal was filled only in the cervical region to the level of resorption by the inverted gutta-percha cone technique. Clinically and radiographically, all follow-up examinations revealed an asymptomatic tooth, evidencing periapical tissue repair and new bone formation. The tooth remained asymptomatic 3 years afterwards. The present case report supports the idea of executing satisfactory intracanal decontamination by chemo-mechanical preparation, thus creating a favourable environment for tissue repair.

A novel ultrasonic tip for removal of filling material in flattened/oval-shaped root canals: a microCT study

Abstract The aim of this study was to evaluate the influence of a novel ultrasonic tip as an auxiliary method for removing filling material from flattened/oval-shaped canals. The null hypothesis tested was that this method does not influence removing the filling material in flattened/oval-shaped canals. Forty-five mandibular incisors were selected and randomly divided into three experimental groups (n = 15) according to different protocols for removing root canal filling material. Group R: Reciproc R25/.08, Group RC: Reciproc R25/.08 + Clearsonic tip, and Group CR: Clearsonic tip + Reciproc R25/.08. The teeth were scanned pre and post-operatively by means of a micro-computed tomography system. Data were analyzed using non-parametric Kruskal-Wallis and Dunn tests (p < 0.05). The percentage of residual root canal filling material between the experimental groups was examined. Statistically significant differences between the experimental groups were found in the root canal. Group R had the highest percentage of residual root canal filling material when compared with Groups RC and CR. The lowest percentage of residual root canal filling material was observed in Group CR. In the apical third of the root canal, statistically significant differences were found between the different protocols. The use of the ClearSonic tip followed by the Reciproc 25/.08 file to remove filling material resulted in the lowest percentage of residuals in the whole root canal and in the apical third.

Effect of Using Different Vehicles on the Physicochemical, Antimicrobial, and Biological Properties of White Mineral Trioxide Aggregate.

INTRODUCTION: This study evaluated the physicochemical, antimicrobial, and biological properties of white mineral trioxide aggregate (MTA) mixed with aqueous and propylene glycol extracts of Arctium lappa L. and Casearia sylvestris Sw. METHODS: The setting-time test was performed according to American Society for Testing and Materials 266/2008 and flowability by American National Standards Institute/American Dental Association 57/2012 standard specifications. The following parameters were assessed: volumetric change by micro-computed tomography; pH level and calcium ion release measured after 3 hours and 1, 3, 7, and 15 days; antimicrobial effect by the dentin decontamination method with intratubular Enterococcus faecalis viability, verified by using confocal laser scanning microscopy; and biocompatibility by histologic-morphometric analyses of inflammatory infiltrate at subcutaneous implant sites after 15, 30, and 60 days. In addition, rat alveolar tissues with implants were processed to measure tumor necrosis factor-alpha and interleukin-10 cytokines by enzyme-linked immunosorbent assay. RESULTS: The plant extracts associated with MTA significantly increased the final setting time; however, they did not influence volumetric change (P > .05) and maintained medium alkalinity and calcium ion release. Propylene glycol extracts showed higher flowability. Casearia sylvestris increased the cementing effect against E. faecalis after 24-hour and 168-hour periods. Histologic evaluation of inflammatory infiltrate showed no significant differences between plant extracts groups and the distilled water group for all periods. Tumor necrosis factor-alpha and interleukin-10 expression was similar among groups (P > .05). CONCLUSIONS: Casearia sylvestris extracts increased the antimicrobial effect of MTA and did not influence biocompatibility but changed some physicochemical properties.

Efficacy of CM-Wire, M-Wire, and Nickel-Titanium Instruments for Removing Filling Material from Curved Root Canals: A Micro-Computed Tomography Study.

INTRODUCTION: The aim of this ex vivo study was to evaluate the removal of filling material after using CM-wire, M-wire, and nickel-titanium instruments in both reciprocating and rotary motions in curved canals. METHODS: Thirty maxillary lateral incisors were divided into 9 groups according to retreatment procedures: Reciproc R25 followed by Mtwo 40/.04 and ProDesign Logic 50/.01 files; ProDesign R 25/.06 followed by ProDesign Logic 40/.05 and ProDesign Logic 50/.01 files; and Gates-Glidden drills, Hedström files, and K-files up to apical size 30 followed by K-file 40 and K-file 50 up to the working length. Micro-computed tomography scans were performed before and after each reinstrumentation procedure to evaluate root canal filling removal. Statistical analysis was performed with Kruskal-Wallis, Friedman, and Wilcoxon tests (P < .05). RESULTS: No significant differences in filling material removal were found in the 3 groups of teeth. The use of Mtwo and ProDesign Logic 40/.05 rotary files did not enhance filling material removal after the use of reciprocating files. The use of ProDesign Logic 50/.01 files significantly reduced the amount of filling material at the apical levels compared with the use of reciprocating files. CONCLUSIONS: Association of reciprocating and rotary files was capable of removing a large amount of filling material in the retreatment of curved canals, irrespective of the type of alloy of the instruments. The use of a ProDesign Logic 50/.01 file for apical preparation significantly reduced the amount of remnant material in the apical portion when compared with reciprocating instruments.