الفهرس 
AIM OF THE STUDYOnly 14 pages are availabe for public view
 |  | from | 62 |  |  |
| | | from | 62 | | |
Abstract
Apical surgery with standard retrograde maneuvers may be challenging in certain cases. Simplifying
apical surgery to reduce operating time and streamline retrograde manipulation is an emerging need in clinical
endodontics.
Aim of the study The aim of the study was to compare the bacterial sealing ability of a calcium silicate-based
sealer with the single cone technique combined with root end resection only, and calcium silicate-based sealer as a
retrograde filling versus MTA retrofilling, and to analyze bacterial viability using confocal laser scanning microscope
(CLSM).
Materials and methods In this in vitro experimental study, 50 extracted human maxillary incisor teeth were
instrumented and randomly divided into five groups: three experimental groups, a positive control group, and a
negative control group (n = 10/group). In the experimental groups, the roots were obturated using the single cone
technique (SCT) and a calcium silicate-based sealer. In group 1, the roots were resected 3 mm from the apex with
no further retrograde preparation or filling. In groups 2 and 3, the roots were resected, retroprepared, and retrofilled
with either a calcium silicate-based sealer or MTA, respectively. group 4 (positive control) was filled with a single
gutta-percha cone without any sealer. In group 5 (negative control), the canals were left empty, and the roots were
sealed with wax and nail varnish. A bacterial leakage model using Enterococcus faecalis was employed to assess the
sealing ability over a 30-day period, checking for turbidity and analyzing colony forming units (CFUs) per milliliter. Five
specimens from each group were examined using CLSM for bacterial viability. Data for the bacterial sealing ability
were statistically analyzed using chi-squared and Kruskal-Wallis tests.
Results The three experimental groups did not show significant differences in terms of bacterial leakage, or bacterial
counts (CFUs) (P > 0.05). However, significant differences were observed when comparing the experimental groups
to the positive control group. Notably, the calcium silicate-based sealer, when used as a retrofilling, yielded the best
sealing ability. CLSM imaging revealed viable bacterial penetration in all the positive control group specimens while
for the experimental groups, dead bacteria was the prominent feature seen.