Evaluation of the root dentine cutting effectiveness of the HERO 642, HERO Apical and HERO Shaper rotary systems.
Different HERO rotary systems were evaluated by pre- and postoperative images of a cross-section of their mesiobuccal root thirds with a stereoscopic magnifier (45x). Fifty mesiobuccal canals of human mandibular first molars were divided into five groups: 1--HERO 642; 2--HERO 642 and HERO Apical; 3--HERO Shaper; 4--HERO Shaper and HERO Apical; 5--NitiFlex files. The perimeter of the canal was calculated using Image Tool software (UTHSCA). Final, post-instrumentation perimeters were compared by Kruskal-Wallis test (P = 0.05). The distribution of the values of the final canal perimeter for each instrumentation method was not statistically significant in any of the thirds (P = 0.174, cervical third; P = 0.874, middle third; and P = 0.631, apical third). An increase in canal perimeter was observed in all groups. In the cervical third the greatest increase was Group 5; in the middle third, Group 4, and in the apical third, Group 2.
Câmara
Andréa Cruz
AC
Department of Prosthetics and Oral and Facial Surgery, MSc Course in Integrated Clinical Dentistry, Faculty of Dentistry, Federal University of Pernambuco, Recife, Brazil.
Aguiar
Carlos Menezes
CM
de Figueiredo
Jose Antonio Poli
JA
D003722:Dental Alloys; D003762:Dental Instruments; D003799:Dental Stress Analysis; D003804:Dentin; D006801:Humans; D008963:Molar; D009532:Nickel; D018915:Root Canal Preparation / Q000295:instrumentation*; D014025:Titanium
D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium