Effect of nickel-titanium alloys on root canal preparation and on mechanical properties of rotary instruments.

The aim of this study was to evaluate the quality of curved root canal preparation, torsional fatigue, and cyclic fatigue of rotary systems manufactured with different NiTi alloys. Ninety single-rooted canals with curvatures of 15° to 30o were scanned and divided into three groups according to the rotary system used: BT-Race (BTR) - 10.06, 35.

Profile of host cell responses to exposure to stressed bacteria in planktonic; dislodged, and intact biofilm mode.

The host defense response to microbial challenge emerging from the root canal system leads to apical periodontitis. The aim of this study was to evaluate the expression of inflammatory cytokines and Nitric Oxide (NO) by macrophages after interaction with Enterococcus faecalis in the: plankton and dislodged biofilm mode; intact biofilm mode stimulated by calcium hydroxide (CH), CH and chlorhexidine (CHX) or Triple Antibiotic Paste (TAP). For this purpose, culture of macrophages from monocytes in human peripheral blood (N=8) were exposed to the different modes of bacteria for 24 hours.

Mechanical Properties of ProTaper Gold, EdgeTaper Platinum, Flex Gold and Pro-T Rotary Systems.

Objective: The aim of this study was to evaluate the cyclic fatigue, torsional behavior and bending resistance of EdgeTaper Platinum [ETP (tip 25, taper 0.06)], Flex Gold [FG (tip 25, taper 0.08)], Pro-T [PT (tip 25, taper 0.

Cyclic Fatigue Resistance of Nickel-Titanium Reciprocating Instruments after Simulated Clinical Use.

Introduction: The aim of this study was to evaluate the cyclic fatigue resistance of different heat-treated nickel-titanium reciprocating instruments in 2 different situations: new and used instruments after preparing 3 curved canals.

Methods: A total sample of 60 nickel-titanium instruments of 3 systems (n = 20 per system) were used in this study: ProDesign R (tip 25, 0.06 taper; Easy Dental Equipment, Belo Horizonte, Brazil), Reciproc Blue (tip 25, 0.

Influence of foraminal enlargement on the apical extrusion of filling material: Volumetric analysis using micro-computed tomography.

The aim of this study was to compare the root canal instrumentation techniques that involve foraminal enlargement versus those not involving it, in regard to the apical extrusion of filling material, using micro-computed tomography (micro-CT). Twenty-two premolars with single canals were instrumented using the ProTaper Universal System and then randomly divided into two groups (n = 11): Group NFE, without foraminal enlargement, and Group FE, with foraminal enlargement. Instrumentation was performed up to 1 mm short of the apical foramen, and foraminal patency was maintained at each instrument change in both groups.

Clinical and self-perceived oral health assessment of elderly residents in urban, rural, and institutionalized communities.

Objectives: This study aims to evaluate the self-perception of oral health according to the physical, psychosocial and pain/discomfort dimensions related to clinical conditions and orofacial pain of elderly people living in three different environments.

Methods: This was an observational, cross-sectional, quantitative study with a population-based approach and nonprobabilistic convenience sampling that included 81 elderly people: 27 resided in institutional homes for elderly individuals, 27 resided in an urban area and 27 resided in a rural area in the interior of Paraíba (PB) in northeastern Brazil.

Results: The Geriatric Oral Health Assessment Index (GOHAI) was used to assess self-perception of oral health, while the Questionnaire for Screening of Patients with Temporomandibular Disorders (QST/TMD) was used to assess the influences of orofacial pain and the biofilm indexes of teeth and prostheses.

Polymerization shrinkage, microhardness and depth of cure of bulk fill resin composites.

The present in vitro study assessed the polymerization shrinkage/PS, Knoop microhardness/KHN and depth of cure/DC of 9 different resin composites : Filtek Bulk Fill Flowable (FBF), Surefill SDR flow (SDR), Xtra Base (XB), Filtek Z350XT Flowable (Z3F), Filtek Bulk Fill Posterior (FBP), Xtra Fill (SF), Tetric Evo Ceram Bulk Fill (TBF), Admira Fusion Xtra (ADM), and Filtek Z350XT (Z3XT). PS was assessed with a µ-CT machine, scanning 64 mm samples (n=8) before and after 20 s curing. KHN and DC were performed with a microhardness tester (n=8 for each group) right after 20 s light curing, with 3 readings per depth at every 0.

Efficacy of reciprocating systems for removing root filling material plus complementary cleaning methods in flattened canals: Microtomography and scanning electron microscopy study.

The aim of this study was to evaluate three reciprocating systems and complementary cleaning methods on filling material removal during retreatment of flattened canals. Thirty-six mandibular incisors were prepared using rotary instruments up to size 25.08 and filled using the single-cone technique.

Computed microtomography evaluation of calcium hydroxide-based root canal dressing removal from oval root canals by different methods of irrigation.

The aim of this study was to evaluate the capacity of conventional irrigation, passive ultrasonic irrigation (PUI), and Easy Clean for removing calcium hydroxide-based root canal dressing from oval root canals. Thirty mandibular uniradicular incisors with oval canals were used, and subjected to chemical-mechanical preparation with Reciproc R40 instruments. The main canal was filled with a paste based on Ca(OH) P.

Comparisons by microcomputed tomography of the efficiency of different irrigation techniques for removing dentinal debris from artificial grooves.

Aim: The aim of this study was compare the capacity of different irrigation protocols for debris removal from artificial grooves and assess the effectiveness of Easy Clean used in different kinematics by means of micro-CT.

Methodology: Fifty acrylic prototyped maxillary incisors were instrumented and included in a muffle. The specimens were longitudinally sectioned, and a longitudinal groove was made on the inner surface of the root canal in one of hemisections, and the dentin debris was inserted into the grooves.

Effect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials.

Objectives: This study evaluated the effect of ultrasonic agitation of mineral trioxide aggregate (MTA), calcium silicate-based cement (CSC), and Sealer 26 (S26) on adaptation at the cement/dentin interface and push-out bond strength.

Materials And Methods: Sixty maxillary canines were divided into 6 groups ( = 10): MTA, S26, and CSC, with or without ultrasonic activation (US). After obturation, the apical portions of the teeth were sectioned, and retrograde cavities were prepared and filled with cement by hand condensation.

Comparison of efficiency of the retreatment procedure between Wave One Gold and Wave One systems by Micro-CT and confocal microscopy: an in vitro study.

Introduction: To compare, by Micro-CT and confocal laser scanning microscopy (CLSM), the ability of the Wave One Gold and Wave One systems to remove filling material from mesial canals of mandibular molars, effective time spent; quantity of extruded material, and percentage of sealer in the dentinal tubules after retreatment and re-obturation procedures.

Materials And Methods: Ten first mandibular molars (n = 20 mesial canals) were prepared and filled with gutta-percha and Endofill sealer mixed with Rhodamine B dye using the single cone technique. After 7 days, the canals were scanned using a high-definition micro-computer tomography with 19-mm voxel size and divided into two groups (n = 10) according to the system used in retreatment: group 1, Wave One (WO), and group 2, Wave One Gold (WG).

Comparative Effectiveness of New Mechanical Irrigant Agitating Devices for Debris Removal from the Canal and Isthmus of Mesial Roots of Mandibular Molars.

Introduction: The aim of this study was to compare the effectiveness of Easy Clean (Easy Dental Equipment, Belo Horizonte, MG, Brazil) in continuous and reciprocating motion, passive ultrasonic irrigation (PUI), Endoactivator systems (Dentsply Maillefer, Ballaigues, Switzerland), and conventional irrigation for debris removal from root canals and isthmus.

Methods: Fifty mesial roots of mandibular molars were embedded in epoxy resin using a metal muffle; afterward, the blocks containing the roots were sectioned at 2, 4, and 6 mm from the apex. After instrumentation, the roots were divided into 5 groups (n = 10) for application of the final irrigation protocol using Easy Clean in continuous rotation, Easy Clean in reciprocating motion, PUI, Endoactivator, and conventional irrigation.

Evaluation of Different Passive Ultrasonic Irrigation Protocols on the Removal of Dentinal Debris from Artificial Grooves.

The aim of this study was to evaluate the influence of different passive ultrasonic irrigation protocols on the removal of debris in artificially created grooves in the cervical, middle and apical root thirds. Forty extracted bovine incisor roots were instrumented to 1 mm of the root apex with a R50 Reciproc instrument and irrigated with 2.5% sodium hypochlorite.

Effect of time and ultrasonic activation on ethylenediaminetetraacetic acid on smear layer removal of the root canal.

The aim of this study was to assess the effect of time and the ultrasonic activation of ethylenediaminetetraacetic acid (EDTA) in removing the smear layer of at root canal. A total of 60 bovine inferior incisors were transversely sectioned and instrumented; A smear layer was added in the root dentin surface. The specimen were then divided into six groups according to the following final irrigation protocols: Group (G) 1: conventional irrigation with sodium hypochlorite (NaOCl); G2: conventional irrigation with NaOCl + EDTA for 20 s; G3: conventional irrigation with NaOCl + EDTA for 60 s; G4: passive ultrasonic irrigation (PUI) with NaOCl; G5: PUI with NaOCl + PUI with EDTA for 20 s; G6: PUI + NaOCl and PUI with EDTA for 60 s.

Use of a 660-nm Laser to Aid in the Healing of Necrotic Alveolar Mucosa Caused by Extruded Sodium Hypochlorite: A Case Report.

The extrusion of sodium hypochlorite through the apical foramen is an accident that can occur during the flushing procedure in endodontic treatment. The symptomatology is immediate and intense, and there is a long period before the tissues return to normal. Low-level laser therapy might be useful as an adjunctive treatment for damaged soft tissues because of its anti-inflammatory and analgesic effects, which may reduce edema and prevent infection.

Conservative surgical treatment of an aggressive calcifying cystic odontogenic maxillary tumor in the young permanent dentition.

Calcifying cyst odontogenic tumor (CCOT) is a rare benign cystic neoplasm of odontogenic origin whose treatment depends on the lesion's localization and histological type. The purpose of this report was to describe a case of extensive calcifying cyst odontogenic tumor involving the maxilla of a 12-year old female patient and the treatment option adopted. The lesion was associated with an impacted first premolar, and the roots of the canine and second premolar were divergently displaced.