Virtually all dentists are intrigued when endodontic post-treatment radiographs exhibit filled accessory canals. Filling root canal systems represents the culmination and successful fulfillment of a series of procedural steps that comprise start-to-finish endodontics. Although the excitement associated with the so-called “thrill-of-the-fill” is understandable, scientific evidence should support this enthusiasm. Moving heat-softened obturation materials into all aspects of the anatomy is dependent on eliminating pulpal tissue, the smear layer and related debris, and bacteria and their byproducts, when present. To maximize obturation potential, clinicians would be wise to direct treatment efforts toward shaping canals and cleaning root canal systems.
Shaping facilitates 3-dimensional (3-D) cleaning by removing restrictive dentin, allowing a more effective volume of irrigant to penetrate, circulate, and potentially clean into all aspects of the root canal system. Well-shaped canals result in a tapered preparation that serves to control and limit the movement of warm gutta-percha during obturation procedures. Importantly, shaping also facilitates 3-D obturation by allowing prefit pluggers to work deep and unrestricted by dentinal walls and move thermosoftened obturation materials into all aspects of the root canal system. Improvement in obturation potential is largely attributable to the extraordinary technological advancements in shaping canals and cleaning and filling root canal systems. Schilder described the classic vertical condensation technique more than 40 years ago. Over time, a few different, yet similar, warm gutta-percha techniques have evolved.