introduction: root fracture is not an instant phenomenon but a result of gradual development of tiny craze lines in tooth structure. recent studies have shown that canal instrumentation has the potential to cause dentinal cracks. the purpose of this study was to evaluate and compare the formation of dentinal cracks caused by protaper rotary system to hand instrumentation. materials and methods:...

statement of problem: root canal cleaning and elimination of the source of infection are the most important basis and the main requirements for successful root treatment since the main cause of failure in root treatment is the permeation of bacteria or their products into the periapical tissues. nowadays, the newly designed and prcsented instruments for canal instrumentation can improve root tr...

Introduction: Although rotary instrumentation has been widely studied in permanent dentition, it is a rather new field of study concerning primary teeth. Purpose: We aimed to evaluate apical displacement and time needed for instrumentation of root canals of primary molars by manual and rotary techniques. Materials and Methods: Root canals of 144 extracted first and second primary maxillary mola...

statement of problem: various factors are involved in causing inflammation following root canal treatment. controlling these factors may relieve the related pain. one of these factors is extrusion of debris beyond the apex. although debris extrusion happens in all instrumentation techniques, researchers have declared that in coronal flaring technique, there is minimum debris extrusion. purpose:...

objective: the aim of this study was to evaluate and compare the cleaning ability and instrumentation time of manual and rotary methods used for preparation of primary anterior teeth. materials and methods: forty-four primary anterior teeth were used in this experimental study. access cavities were prepared and india ink was injected into the canals. the samples were divided into three groups a...

background: the purpose of this study was to compare the effi cacy of endovac irrigation system and side-vented closed ended needle (max-i probe) in removing smear layer from root canals at 1 mm and 3 mm from working length using protaper rotary instrumentation. materials and methods: a total of 50 freshly extracted maxillary central incisors were randomly divided into two groups after complete...

apical extrusion of debris and irrigants during cleaning and shaping of the root canal is one of the main causes of periapical inflammation and postoperative flare-ups. the purpose of this study was to quantitatively measure the amount of debris and irrigants extruded apically in single rooted canals using two reciprocating and one rotary single file nickel-titanium instrumentation systems.sixt...

introduction: one of the most common complications of root canal treatment is postoperative pain. the aim of the present clinical trial was to compare the severity of postoperative pain after root canal preparation with race rotary system and hand k-flexofile. methods and materials: a total of 96 mandibular first and second molars were divided into two groups ( n =48) based on root canal prepar...