With improvement in material properties of ceramic restorative materials, these materials have been used as the definitive restoration material instead of the dental alloy, even in the posterior region. The incomplete fit of full crown restorations remains a critical problem for dentists, leading many researchers to study this problem. The distribution and magnitude of stress at any point can b...

Introduction: The aim of the present study was to compare hand stainless steel K-files and Nickel-titanium Profile 0.04 taper 29 series rotary instruments for their efficiency, procedural errors and time consumed in preparation of root canal system. Materials and Methods: A total of 46 maxillary and mandibular first premolars extracted for orthodontic purposes were collected (two contralateral ...

AIM To determine several properties including torsional and fatigue limits, as well as torque during canal preparation, of Hyflex, a rotary instrument manufactured from so-called controlled memory nickel-titanium alloy. METHODOLOGY The instruments were tested in vitro using a special torque bench that permits both stationary torque tests according to ISO3630-1 and fatigue limit determination,...

INTRODUCTION The aim of the present study was to compare hand stainless steel K-files and Nickel-Titanium Profile 0.04 taper 29 series rotary instruments for their efficiency, procedural errors and time consumed in preparation of root canal system. MATERIALS AND METHODS A total of 46 maxillary and mandibular first premolars extracted for orthodontic purposes were collected (two contralateral ...

Background and Aim: Preparation of root canal with rotary nickel-titanium (NiTi) instruments may potentially create microcracks that can lead to vertical root fracture. This study aimed to compare the incidence of crack formation by BioRaCe and Edge Taper Platinum systems in the mesiobuccal canals of extracted first mandibular molars. Materials and Methods: In this experimental study, 50 first...

BACKGROUND Cleaning and shaping of the pulp canal is one of the most important steps of endodontic therapy. Serious complications occur by the apical extrusion of bacteria during the instrumentation procedures. Both crown-down (CD) and full-length linear motion (FM) techniques are routinely used as a component of taper rotary instrument procedures for achievement of thorough cleaning and shapin...

INTRODUCTION Taper is a factor that determines final root canal dimensions and, consequently, the dimensions of the space for the cleaning action of irrigants. Therefore, the aim of the present study was to investigate the influence of taper on root canal cleanliness. METHODS Root canals of 45 mandibular incisors were divided into 3 groups and prepared with GT rotary files to apical preparati...

OBJECTIVES The purpose of this in vitro study was to assess the effect of root canal preparation size and taper on the amounts of glucose penetration. MATERIAL AND METHODS For conducting this experimental study, eighty mandibular premolars with single straight canals were divided randomly into 2 experimental groups of 30 samples each and 2 control groups. Using K-files and the balance force t...

AIM To evaluate the influence of reciprocating single-file instrumentation with different working lengths (WL) and apical preparation sizes on apical bacterial extrusion. METHODOLOGY Sixty-eight human single-rooted pre-molars were used. Conventional access cavities were prepared, and the root canals were contaminated with an Enterococcus faecalis suspension and incubated at 37°C for 30 days. ...