ABSTRACT
Objective@#The purpose of this study was to investigate the differences in the anti cyclic fatigue performance of Woride KS (WKS), Proteper Gold (PTG), and Hyflex CM (HCM) nickel titanium instruments with different tip diameters in curved root canal models, and to provide reference for the targeted selection of suitable nickel titanium instruments in clinical preparation of curved root canals.
ABSTRACT
Instrument separation is a very common mishap in routine endodontic practice. Although fractured fragment does not affectthe prognosis of the case, it may affect the subsequent steps in endodontic therapy, such as chemomechanical preparation,obturating root canals. In case of separated instrument, attempts should be made to retrieve the instrument where possible orone should try to bypass the fragment. This case report describes the retrieval of a separated instrument from central incisorof 18-year-old boy
ABSTRACT
@#Dental operating microscope is recommended to complicated root canal therapy, for it could provide increased lighting and superior magnification, so that the survival rate of tooth is highly increased. More refined access of cavity preparation, canal cleaning, shaping and obturating are realized under microscope. This article combined literature reviews with the writers’ clinical experience, and it aims at helping clinicians to improve their ability to more accurately performance and minimally invasive endodontic procedures, such as locating hidden canals obstructed by calcifications, canals reduced in size, removing materials, reducing ledge formation, apical transportation, and repairing perforations.
ABSTRACT
Objective:To analyze the morphological characteristics of damaged Hero642 Ni-Ti dental files, and explain the relationship between deformation and fracture.Methods:71 discarded files were observed under naked eyes and stereomicroscope. 5 of which were observed under S360 scanning electronic microscope (SEM), and typical photos were taken for analysis.Results:The damage of Hero642 Ni-Ti dental files was characterized by fracture, tightened or loosened spiral and some kind of deformation detected at more than 35 times magnification. Under SEM, the dimple pattern was represented in the fracture surface of the files. Conclusion:Most Hero642 Ni-Ti files fractured within 4 mm from the tip which belongs to the pattern of ductile fracture.