Evaluating the paper point technique for locating the apical foramen after canal preparation.

OBJECTIVE Despite not having been formally evaluated in the endodontic literature, claims have been made regarding the acceptability of the paper point technique (PPT) in estimating the location of the apical foramen (AF). Our aim was to investigate the repeatability and accuracy of PPT in estimating AF location in a cohort of dental patients. STUDY DESIGN Root canals with </=10 degrees of curvature (n = 71) in unsalvageable anterior and premolar teeth were measured using PPT as described in the literature. An endodontic file was cemented in each canal to the position indicated by PPT. Teeth were extracted and microscopic computerized tomography scanned. RESULTS The PPT was 0.5 mm short to 0.5 mm long of AF in 87% of the canals. Repeated measurements in a given canal were within 0.19 mm of each other 95% of the time. CONCLUSION For relatively straight root canals, PPT appears to be similar to current clinically acceptable techniques in estimating AF location.