Efficacy of bacterial removal from instrumented root canals in vitro related to instrumentation technique and size

Nonsurgical Root Canal Therapy of Large Cystic Periapical Lesions Using Simple Aspiration and LSTR (Lesion Sterilization and Tissue Repair) Technique: Case Reports and Review

“…Instrumentation of mandibular canines/bicuspids to size #80 [15,23] and the mesial roots of mandibular molars to a size #60 and demonstrated an 81 to 100% reduction in remaining bacteria. Rollison et al showed larger file sizes to a #50 produced greater reduction in remaining bacteria than those instrumented with a #35 file [24]. Tan et al compared hand versus rotary files using specific criteria for apical enlargement [25].…”

Calcium hydroxide fillings in curved canals: influence of apical enlargement using the rotary systems ProTaper, K3, and two hand instrumentation techniques

“…The majority of studies demonstrate that larger apical preparation sizes result in a greater reduction in the remaining bacteria and debris compared to smaller apical diameters 17,33 . On the other hand, over-enlargement may cause weakening of dental structure 31 and, especially when hand techniques are used, may lead to apical deviation 34 .…”

Apical prepration size in infected root canals

“…7,8) 따라서 치근단 3 mm 이내 지역인"critical zone"에서의 적절한 근관확대의 크기는 개개 치아의 근단공의 해부학적 형태와 직경 및 근관감염 정도를 토대로 신중하게 결정해야 한다. 9,10) How can we estimate the size of apical constriction as accurate as possible? …”