introduction: pulpectomy is the preferred treatment for restorable primary teeth with symptomatic irreversible pulpitis or periradicular lesion. considering the rather new application of rotary files for pulpectomy of primary teeth, the aim of this study was to compare the cleaning efficacy and instrumentation time of hand k-files and mtwo rotary system for preparation of human primary molars. ...

introduction: transportation is an important iatrogenic endodontic error which might cause failure. this study evaluated the canal transportation caused by neoniti and protaper instruments, using cone-beam computed tomography (cbct) cross sections. methods and materials: this in vitro experimental study was performed on 40 mesiobuccal roots of maxillary first molars. the teeth were scanned with...

introduction: the aim of this in vitro study was to compare the effect of hand and rotary instruments on fracture strength of tooth roots. materials & methods: thirty two teeth were randomly divided into two experimental groups of 15 each and one negative control group with two samples. in group 1, step-back technique with conventional stainless steel k-files was used, and in group 2, instrumen...

the aim of this study was to assess the efficacy of apical negative pressure (anp), manual dynamic agitation (mda), passive ultrasonic irrigation (pui) and needle irrigation (ni) as final irrigation activation techniques for smear layer removal in curved root canals.mesiobuccal root canals of 80 freshly extracted maxillary first molars with curvatures ranging between 25° and 35° were used. a gl...

introduction: root canal preparation is an important process in endodontic therapy. nickel-titanium (niti) rotary file system can be used in single length technique (simultaneous technique) without early coronal enlargement, as well as in crown-down method. the purpose of this in vitro study was to compare single length with crown-down methods’ shaping ability using mtwo niti files . materials ...

introduction: this study compared apical dye penetration using lateral condensation technique (lc) and lc technique with a reciprocal handpiece (mechanical lateral condensation or mlc) as a new method. materials and methods: forty-eight human extracted straight canine teeth were used. after crown amputation, the teeth were randomly divided into four experimental groups of 10 teeth each and two ...

introduction: the purpose of this in vitro study was to compare working length (wl) changes after straight-line access (sla) and different coronal flaring (cf) methods. materials and methods: coronal access preparations were made (without sla) in molar teeth to allow access to 120 canal orifices with a hand file. the suitable cusp and root tips were then flattened to facilitate reproducible and...

introduction: the purpose of this study was to evaluate external root surface temperature rise during post space preparation using la axxess bur, beefill pack system, and peeso reamer drill. materials & methods: the distal canals of forty-five extracted human permanent mandibular first molars were instrumented in crown-apical manner and obturated with lateral condensation technique. teeth were ...

introduction: fearless removal of tooth structure during canal preparation and shaping has negative effects on the prognosis of treatment. on the other hand, sufficient pre-enlargement facilitates exact measurement of the apical size. the present in vitro study aimed to compare the efficacy of gates-glidden drills, k3, protaper, flexmaster and race instruments in dentin removal during coronal f...