1. Department of Endodontics, Periodontics, and Prosthodontics, School of Dentistry, University of Maryland Baltimore, Baltimore, MD, USA
2. Department of Endodontics, Temple University, Philadelphia, PA, USA
3. Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland Baltimore, Baltimore, MD, USA
4. Department of Endodontics, School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA