the purpose of this ex- vivo study was to evaluate the fracture resistance of simulated immature teeth, obturated with gutta-percha or resilon and reinforced by either composite resin or fiber post.eighty-four human maxillary incisors were divided into seven groups (n=12). teeth in all groups were prepared until peeso #5 (1.5mm) could be passed through the apex. root ends received 4mm of mta pl...

The amounts of apical enlargement have been a controversial issue for a long time. The enlargement of the apical part of the canal may severely impact the endodontic prognosis. Enlargement of the apical portion to a larger size may negatively affect the ability to control the filling material during root canal obturation. In addition, an open-apex increases the risk for overfilling which has be...

In recent times, interest has centred on the use of mineral trioxide aggregate (MTA), due to its wide array of application in the treatment of complications following dental trauma. These conditions include teeth with exposed pulp, root fracture and pulp necrosis located in the coronal part of the pulp [24-26]. It is the material of choice as an apical plug during the short-term (one-visit) ape...

When filling root canals of teeth with apical resorption near the mandibular canal, there is a risk that material will go beyond apex into region which can lead to serious damage innervation this area. In most cases, modern approaches and technologies in endodontics allow achieve formation dentinal plug area, thus minimizing traumatization patient.
 Background. Improving efficiency endodon...

Temperature is one of the effective parameters in erosion of spark plug electrodes. In this research, temperature of spark plug was measured in engine's different operation conditions with two types of fuels: compressed natural gas and gasoline. Test results showed that, temperature of center electrode is lower than ground electrode and maximum difference between them is 110ºC that occurs at...