Microbial Complications: Etiology

After endodontic treatment has been initiated, anything that jeopardises the integrity of the rubber dam seal and field disinfection can be regarded as a microbial complication. The most common microbial complications are listed below:
1) rubber dam not used or leaking rubber dam
2) too short or too long (bleeding) preparation length
3) all canals not found
4) contaminated endodontic materials
5) insufficient apical preparation (too small instruments)
6) failure to fill the whole root canal with the local medicament
7) leaking temporary restoration: too thin, leaking material, cotton pellet under
the filling
8) leaking old fillings during treatment
9) poor cleaning of pulp chamber during and after treatment
10) gutta-percha in the pulp chamber after treatment
11) coronal leakage associated with the permanent restoration