Aim: The aim of this study was to observe the existence and assess the quality of obturation of uninstrumented recesses in oval canals.
Methodology: The balanced force technique was used in two groups of oval canals in human mandibular incisors. The canals in group 1 were enlarged to conventional sizes, whereas canals in group 2 were enlarged more widely. All canals were obturated with cold laterally condensed gutta-percha. Two horizontal sections were cut in the apical portion of each filled root. Images of the cross-sections were scanned and analysed using the KS100 Imaging system.
Results: Uninstrumented recesses appeared in 13 (65%) oval canals. The recesses in five of these 13 canals were obturated without visible voids. The recesses in the other eight canals were either obturated with visible voids or completely unfilled. The percentage of filled area was significantly higher in group 1 than in group 2 (P < 0.05).
Conclusions: Uninstrumented recesses may be left in many oval canals after preparation using the balanced force technique and these recesses may often not be completely obturated with cold laterally condensed gutta-percha.