Burch/Hulen OOO, 1974 Microscope Study Furcal POEs 76% molars Hess DeDeus Cavit Burch/Hulen OOO, 1974 Microscope Study Furcal POEs 76% molars 98.6o F Kulild Broth Lowmann OOO, 1973 Dye Study Patent POEs Coronal to Mid 1/3 in 59% Mand Molars Weine Gutmann Cartoonish illustration suggests that, despite sealing primary exits and many peripherals, leaving the floor unsealed AFTER treatment can be risky. Slide contains a small sampling of the list of authors who have demonstrated that the pulpal system is elaborate and has POEs in the coronal 1/3. Green Vertucci Pineda cjm

Cavit Cotton Broth Not only is it risky to leave the floor unsealed AFTER endo therapy, it is arguably at least as risky to leave it unsealed BETWEEN VISITS when inflammatory byproducts can egress from the system into the surrounding structures and cause irreparable damage to supporting structures. It is relatively easy to address apical pathosis, but much more complex to address furcal deterioration…. cjm

10 weeks post-access with cotton pellet “well-sealed” with cavit This patient disappeared for 10 weeks after access and temporization with a cotton pellet and cavit…. 10 weeks post-access with cotton pellet “well-sealed” with cavit cjm

Coronally-positioned POEs Start at the chamber floor and have limited opportunity to address coronally-located POEs Start at occlusal surface and address coronally- positioned POEs by design d/t additional condensing strokes before even reaching chamber floor After exhaustive examination of the floor, exploration into the cervical aspect of all canals and creation of “straight-line” access, Canal Projection seals the floor of the chamber at the first treatment visit (usually). Additionally, “elongating” the canals by Projecting them also changes the dynamics of the hydraulics within each of the now-separated canals, creating a circumstance where more coronally-positioned POEs are more likely to be sealed during warm vertical obturation. The illustrations show that “conventional” warm vertical condensation strokes begin at the chamber floor while, with “elongated” canals, the strokes begin at the occlusal surface, allowing for numerous “waves of condensation” before even reaching the floor…. cjm

This MB2 canal emanates from the P orifice This MB2 canal emanates from the P orifice! It was only addressed by default b/c of improved hydraulics of “elongated” canals…. In this maxillary molar, an exhaustive high-magnification search of the floor and sub-orifice level in each canal did not reveal the MB2 canal. Nevertheless, because of the “elongated” canals—and specifically the elongated P canal—created by Projection, the undiscovered MB2 canal was obturated during the warm GP downpack. The patient being an ER doc, never returned for proper cleaning/shaping/obturation of the MB2 canal…. cjm MBD Rule

“Elongation” of the canals adds condensation strokes; that creates greater opportunity to address all POEs—especially those more coronally-positioned. cjm

Micturating Molar Various POEs more coronally-positioned in Projected Canal cases…. cjm

THE END……… cjm