Comparison of endodontic file tip quality

Tip angulation and four visual characteristics denoting manufacturing quality of endodontic files were studied. One-hundred eighty K-type, Hedstrom, and Flex-type files from two manufacturers (Kerr and Mallefer) were evaluated. Photomicrographs (x 115) were made of each file. Two evaluators examined the photomicrographs. Tip angulation was studied to determine if files were compliant with ANSI/ADA Specification Nos. 28 and 58. The four visual characteristics compared in the study were symmetry versus asymmetry, smooth versus irregular, tip configuration, and shoulder configuration. Statistical analysis was made using the chi-square method. Mallefer files appear to be more in conformity with specifications for tip angle and more meticulously manufactured than Kerr files. Kerr Hedstrom files appear to conform less often to tip angle specifications than Kerr K-type or K-Flex files. K-type and Flex-type file tips appear to be better manufactured than Hedstrom file tips. Certification status of a file manufacturer did not correlate with a higher level of compliance with tip angulation specifications or with a better machined file tip.