Selective Root Retreatment: A Novel Approach.

Root canal retreatment is traditionally considered an "all or none" treatment approach. It is typically recommended that all restorative and obturation materials be removed from all roots regardless of the presence or absence of periapical pathosis. In contrast, surgical endodontics is not viewed as an "all or none" treatment approach. Traditionally, only the diseased root(s) is addressed via root-end resection and root-end filling. The use of cone-beam computed tomographic imaging allows for a more accurate evaluation of the periapical status of individual roots associated with multirooted teeth. This information has introduced a novel and conservative treatment alternative for previously endodontically treated teeth with multiple roots presenting with post-treatment disease. This new approach is termed selective root retreatment. Advanced imaging allows the clinician to make predictable treatment decisions with respect to the presence or absence of periapical pathosis of individual roots as opposed to making assumptions about the tooth as a whole. Selective root retreatment combines the approach of nonsurgical retreatment with the selectivity of surgical root resection. In this manner, retreatment could be limited to a single root or roots clearly showing periapical pathosis while leaving the root(s) with no visible or perceived pathosis untouched.

Assessment of the separation incidence of reciprocating WaveOne files: a prospective clinical study.

INTRODUCTION: Despite metallurgical advancements in the nickel-titanium file manufacturing process, file separation remains a concern. The purpose of this prospective clinical study was to assess the separation incidence of the reciprocating WaveOne file (Dentsply Tulsa Dental Specialties, Tulsa, OK) when used to prepare root canals of posterior teeth. METHODS: File separation incidence was assessed over an 18-month period in which 4 experienced and calibrated endodontists performed conventional endodontic treatment on posterior teeth using the WaveOne file system. The separation incidence was determined based on both the number of teeth and the number of canals instrumented during this time period. RESULTS: A total of 2,215 canals (711 teeth) were treated. Three instruments (two 21.06 and one 25.08) separated during use and were deemed to be irretrievable. The overall instrument separation incidence in relation to the number of canals shaped was found to be 0.13% (0.42% teeth). CONCLUSIONS: Based on the results of this study, the incidence of endodontic instrument separation when using the WaveOne reciprocating file was considerably low.

Antimicrobial effect of triclosan and triclosan with Gantrez on five common endodontic pathogens.

Microbial control of the root canal system is one of the key objectives of root canal therapy. Triclosan is a widely accepted broad spectrum antimicrobial agent proven to be effective against many gram-positive and gram-negative bacteria. Triclosan acts by blocking bacterial fatty acid biosynthesis. The addition of Gantrez copolymer has been shown to enhance the antimicrobial activity of triclosan. The purpose of this study was to determine the minimum inhibitory and bactericidal concentrations of triclosan and triclosan with Gantrez against Prevotella intermedia, Fusobacterium nucleatum, Actinomyces naeslundii, Porphyromonas gingivalis, and Enterococcus faecalis. The minimum inhibitory concentration (MIC) of both test solutions was determined for each of the 5 microorganisms by using microtiter serial dilutions. Samples were streaked on 5% sheep blood agar plates and placed in an anaerobic incubator to determine the minimum bactericidal concentration (MBC). The MBC of triclosan ranged from 12-94 microg/mL. The MBC of triclosan with Gantrez ranged from <0.3-10.4 microg/mL. The addition of Gantrez enhanced the bactericidal activity of triclosan. Both triclosan and triclosan with Gantrez demonstrated bactericidal activity against the 5 specific endodontic pathogens.