Objective. The objective of this study was to compare the effectiveness of two file systems with two solvents for the removal of endodontic obturation materials from teeth. Background. Gutta percha and RealSeal are two common endodontic obturation materials that must be removed to retreat teeth, however, the effectiveness of file systems and solvents to remove these materials is controversial. Methods. Human extracted teeth (n = 80) were instrumented and obturated with either Gutta- percha/ AH Plus cement (Dentsply DeTrey, Konstanz, Germany) or RealSeal (SybronEndo, Orange, CA) bonded obturation material according to manufacturer instructions. Each tooth was retreated using either one of two rotary instrumentation file systems: Protaper Retreatment Files (Dentsply, Tulsa, OK) or EndoSequence Files (Brasseler, Savannah, GA). Each of the file systems was tested using Chloroform Solvent or Orange Solvent retreatment agents. The teeth were processed for scanning electron microscopy and micrographs were categorized using a double blind scale for obturation material removal at 2000x magnification. Data was analyzed by Chi-square at a significance of 95%. Results. We found that Chloroform and Agent Orange are equally effective solvents to remove the obturation materials from the root canals of teeth (p \u3e 0.05). Both the Protaper Retreatment and EndoSequence file systems were also similarly effective (p \u3e 0.05). Conclusion. The use of the retreatment solvents: Chloroform and Agent Orange, and the Brassler Sequence and ProTaper files are equally effective to remove Gutta percha and RealSeal obtuation materials from the root canals of teeth. Grants. This research was sponsored by the NSU Health Professions Division