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eliminates constrictions in the coronal region cleans coronal 2/3’s of canal b/4 apical 1/3 is entered limits the engagement of each file ~ 2-5mm reduces the impact of canal curvature better tactile awareness during apical shaping. Foramen Last.
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eliminates constrictions in the coronal region cleans coronal 2/3’s of canal b/4 apical 1/3 is entered limits the engagement of each file ~ 2-5mm reduces the impact of canal curvature better tactile awareness during apical shaping Foramen Last • allows greater volume of irrigant penetration • minimizes transportation, zipping, ledging • less irritants and toxins pushed through the foramen • working length less likely to change • less stress, minimizes breakage
The ‘Apical Control Zone’ is a matrix-like region created in the apical third of the root canal space. The zone demonstrates an exaggerated taper from the clinician defined apical constriction whether this is spatially a linear or point determination. This enhanced taper in the apical control zone provides resistance form against the condensation pressures of obturation and acts to prevent the extrusion of the filling material during obturation. Apical Control Zone
.2 mm taper 0.0 mm 20 0.25 mm 25 0.5 mm 30 0.75 mm 35 1.0 mm 40 2.0 mm 42 3.0 mm 44 4.0 mm 46 David Rosenberg
Distal Root 1 mm from Apex Canal not instrumented to the correct diameter Necrotic Tissue
Distal Root 1 mm from Apex Isthmus Necrotic Tissue and Debris Canals not instrumented to the correct diameter
Median of maxillary canal diameters 1mm from apex Mx. cent. incisor .34mm Lateral incisor .45mm Canine .31mm Premolar .37mm MB1, MB2 (molar) .19mm DB .22mm Palatal .33mm What does the literature say about canal diameters? Wu et al 2000
Median of mandibular canal diameters 1mm from apex Md. central incisor .37mm Lateral incisor .37mm Canine .31mm Premolar .35mm MB (molar) .40mm ML .38mm Distal .46mm What does the literature say about canal diameters? Wu et al 2000