A comparison study on endodontic interappointment emergencies between protaper NiTi instruments and stainless steel hand-used files in curved root canal preparation

Objective To compare the incidence of endodontic interappointment emergencies(EIAE) among engine-driven Protaper NiTi instruments,hand-used Protaper NiTi instruments and stainless steel hand-used files in curved root canal preparation.Methods The 165 teeth with curved root canals,which suffered from chronic periapical disease were divided into three groups at random.In group A,root canals were prepared with engine-driven Protaper NiTi instruments.In group B,root canals were prepared with Hand-used Protaper NiTi Instruments.In group C,root canals were prepared with stainless steel hand-used files.The incidences of EIAE were recorded and statistically analyzed.Results The incidences of EIAE between group A and group B had no significant difference(P0.05),and were significantly lower than those of group C(P0.05);there was one instrument separation in group A.Conclusion The incidence of EIAE can be reduced by using Protaper NiTi instruments,but engine-driven Protaper NiTi instruments may increase the incidence of instrument separation.