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            Davis RD, Marshall JG, Baumgartner JC.  Effect of early coronal flaring on working length change in curved canals using rotary nickel-titanium versus stainless steel files.  J Endodon 2002;28:438-442

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            Wilson BL, Broberg C, JC Baumgartner, Harris C, Kron J.  Safety of electronic apex locators and pulp testers in patients with implanted cardiac pacemakers or cardioverter/defibrillators.  J Endod 2006;32:847-852.

Optional
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