Aim: to compare the shaping ability of two rotary systems (Protaper Universal and
Protaper Next) and K-file hand instruments in curved root canals of extracted human
molars.
Materials and methods:Thirty extracted molars with curved canals were cho
sen. The
curvature of root canals was determined (15-40o) then the sample was randomly divided
into three groups: n1=n2=n3=10. Group(1): was prepared using K-file hand instruments
(Stand), group(2): prepared by Protaper Universal (PTU), whereas group3: prepared by
Protaper Next (PTN).The curvature after preparation and Time preparationwere evaluated.
Data were collected and statistical analysis was conducted.
Results: The three instrument systems (PTU, PTN, Stand) have caused significant
change in original canal curvature(P<0.05). On the other hand, there were no significant
differences between systemsin straightening of canal curvature (P>0.05). However, both
systems: PTN, Stand were significantly faster than PTU during preparation of curved
canals (P<0,001).Conclusion: under the conditions of this study, it can be concluded
thatall instruments caused changing in original canal curvature. However, the new
generation PTN was faster than old one PTU.
Aim of Study: The objective of this study was to compare the shaping ability of
ProTaper Rotary instruments (Universal, Next), Hand ProTaper instruments and traditional
hand instruments in long oval-shaped root canals.
Methods and materials: Forty
human teeth with long oval-shaped root canals were
sectioned at 3 levels in the coronal, middle and apical third. A modified Bramante technique
was used and analyzed changes in root canal maximum buccolingual and mesiodistal
canal dimensions (ΔBL ,ΔMD) and changes in surface area (ΔA) , under (10X) magnification.
Where the sample was divided into four groups each one contains (N=10) teeth and
prepares by one of the four instrumentation systems. The morphological changes were
analyzed by software Program (Auto Cad 2013).
