This study used computed tomography (CT) to compare apical canal transportation in mesiobuccal canals of maxillary molars prepared with different techniques. Sixty teeth were assigned to 3 groups (n=20), according to the technique used for root canal instrumentation: hand instrumentation with K-Flexofiles, K-Flexofiles activated by an oscillatory system and ProTaper NiTi rotary system. Pre and ...

PURPOSE To evaluate the efficacy of different obturation techniques in root canals instrumented either by hand or rotary instruments with regard to the percentage of gutta- percha-filled area (PGFA). MATERIALS AND METHODS One hundred and sixty extracted mandibular premolars with single, straight root canals were studied. Root canals were prepared to an apical size of 30 by hand with a modifie...

OBJECTIVES The aim was to evaluate dentinal crack formation after root canal preparation with ProTaper Next system (PTN) with and without a glide path. MATERIALS AND METHODS Forty-five mesial roots of mandibular first molars were selected. Fifteen teeth were left unprepared and served as controls. The experimental groups consist of mesiobuccal and mesiolingual root canals of remaining 30 teet...

BACKGROUND The aim of this in vitro study was to compare the shaping characteristics of two types of nickel-titanium endodontic file systems with regard to the following parameters: Canal straightening, Canal deviation and Instrumentation time. MATERIAL AND METHODS Fifty severely curved canals simulated in resin blocks were prepared to an apical size 25 using Protaper Universal orNeolix syste...

PURPOSE The aim of this study was to compare the cleanliness of root canal walls after retreatment using ProTaper Next (PTN), ProTaper Universal Retreatment (PTR) nickel-titanium (NiTi) systems and Hedström hand files in curved mesial canals of mandibular molar teeth and the time required for gutta-percha and sealer removal. MATERIALS AND METHODS Ninety mandibular molar teeth with curved mesi...

INTRODUCTION The purpose of this study was to identify the influential factors responsible for clinical instrument separation of reused ProTaper Universal rotary instruments (Dentsply Maillefer, Ballaigues, Switzerland). METHODS Six thousand one hundred fifty-four root canals in 2,654 teeth were prepared using ProTaper Universal files in endodontic clinics. Separation incidence was determined...

introduction: the aim of this in vitro study was to evaluate the effect(s) of three canal lubricants i.e. sodium hypochlorite, rc-prep as the paste form of ethylenediaminetetraacetic acid (edta) and aqueous edta, on the occurrence/incidence of fracture, deformity and metal slivering of protaper rotary instruments. methods: a total of 120 mesial canals ( i.e. mesiobuccal and mesiolingual) of fir...

INTRODUCTION The retreatability of recent calcium silicate or mineral trioxide aggregate (MTA) sealers has not yet been assessed. The aim of this study was to evaluate the removal of 2 MTA-based sealers (MTA Fillapex [Angelus Soluções Odontológicas, Londrina, PR, Brazil] and MTA Plus [Prevest-Denpro, Jammu City, India]) using a rotary retreatment system, considering an epoxy resin sealer (AH Pl...

Preparation of the root canal system is a crucial step in treatment. Endodontically treated teeth differ structurally from healthy, untreated teeth. This can lead to cracking by creating pressure on wall, reducing fracture resistance tooth. Different designs, including cross-sectional shape, tip, taper, flute, radial land, helix angle, rake and pitch, influence outcome preparation risk fracture...

The aim of this study was to investigate whether endodontically retreated teeth filled with Resilon are more resistant to fracture than those filled with guttapercha following hand or rotary removal techniques. Seventy-two upper anterior human teeth were selected, decoronated and reduced to 12 mm. The canals were shaped using rotary ProTaper files and randomly assigned into two groups (n=36). O...