Purpose: To assess the in vivo intracanal microbial status of the apical root canal system of mesial roots of human #36 or 46 with primary apical periodontitis using transmission electron microscopy
N= 16 apical mesial roots of mandibular first molars
- LA, RD isolation, disinfected by NaOCl, access, WL. All MB canals were instrumented using K hand files #25. All ML canals were instrumented using Lightspeed NiTi until a #40 apical size.
- Irrigation with 5.25% NaOCl, 17% EDTA, obturated by lateral condensation of GP & ZOE cement.
- The apical third of mesial roots was carefully removed by surgery after completing the RCT.
- Control: +ve , extracted teeth with PA; -ve, extracted healthy premolars
Most highlighted Results:
1.Microorganisms were found in the apical root canal system in 14/16 (88%)
2.11\16 root tips revealed an isthmus between canals, 10/11 showed presence of microorganisms.
3.Accessory root canals were present in 8 \16, of which 5 contained a mixed microbial flora.
4.The microbes were located in inaccessible intercanal isthmus, and accessory canals, mostly as biofilms.
Findings highlight the importance of chemomechanical measures in order to disrupt the biofilms to ensure the most favorable long-term prognosis for treatment of infected root canals.