Persistent Extraradicular Infection in Root-filled Asymptomatic Human Tooth: Scanning Electron Microscopic Analysis and Microbial Investigation after Apical Microsurgery

• Published in: Journal of endodontics Vol. 37; no. 12; pp. 1696 - 1700
• Main Authors: Signoretti, Fernanda G.C., DDS, MSc, Endo, Marcos S., DDS, MSc, Gomes, Brenda P.F.A., DDS, MSc, PhD, Montagner, Francisco, DDS, MSc, PhD, Tosello, Fernanda B., DDS, Jacinto, Rogério C., PhD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2011
• Subjects: Actinomyces - isolation & purification; Adult; Aluminum Compounds - therapeutic use; Apical periodontitis; apical surgery; Apicoectomy - methods; Asymptomatic Diseases; Bacteroides - isolation & purification; Biofilms; Calcium Compounds - therapeutic use; Clostridium botulinum - isolation & purification; Dental Fistula - therapy; Dentistry; Drug Combinations; Endocrinology & Metabolism; endodontic failure; endodontic outcome; Female; Follow-Up Studies; Gram-Positive Bacteria - isolation & purification; Humans; Microscopy, Electron, Scanning; Microsurgery - methods; nonsurgical retreatment; Oxides - therapeutic use; Peptostreptococcus - isolation & purification; Periapical Periodontitis - microbiology; Periapical Periodontitis - surgery; Piezosurgery - methods; Propionibacterium - isolation & purification; Retreatment; Retrograde Obturation - methods; Root Canal Filling Materials - therapeutic use; root canal infection; Root Canal Preparation - methods; Silicates - therapeutic use; Tooth Apex - microbiology; Tooth Apex - pathology; Tooth, Nonvital - therapy; endodontic outcome; root canal infection; endodontic failure; Apical periodontitis; apical surgery; nonsurgical retreatment
• ISSN: 0099-2399; 1878-3554
• DOI: 10.1016/j.joen.2011.09.018

Abstract Introduction Procedural accidents have a negative effect on healing and might contribute to the persistence of infections in inaccessible apical areas, requiring surgical intervention. This report describes a case of persistent apical periodontitis of a lower left first molar associated with the sinus tract and a periapical lesion that required nonsurgical endodontic retreatment and apical surgery for resolution. Methods The tooth had received endodontic treatment 3 years ago and had to be retreated using the crown-down technique with chemical auxiliary substance (2% chlorhexidine gel), foramen patency, and enlargement and was filled in a single appointment. The occlusal access cavity was immediately restored with composite resin. After 1 month, it could be observed that the sinus tract persisted and, radiographically, the lesion remained unaltered. Therefore, endodontic microsurgery was indicated. Apical microsurgery was performed under magnification with the use of a dental operating microscope including apicectomy, root end with ultrasound, and sealing with mineral trioxide aggregate. A microbiological sample was collected from the apical lesion. The resected distal root apex was observed by scanning electron microscopy. Results The following species were detected: Actinomyces naeslundii and Actinomyces meyeri , Propionibacterium propionicum , Clostridium botullinum , Parvimonas micra , and Bacteroides ureolyticus ; scanning electron microscopic analysis revealed bacterial biofilm surrounding the apical foramen and external radicular surface. Gutta-percha overfilling at the apex because of a zip caused during initial endodontic treatment could be observed. A 6-month follow-up showed apparent radiographic periapical healing, which progressed after 24 months. Conclusion Gram-positive anaerobic bacteria and extraradicular biofilm seem to participate in the maintenance of persistent periapical pathology, and endodontic retreatment followed by periapical microsurgery proved to be a successful alternative in the resolution of persistent extraradicular infections.