Study of the penetration of a bio-ceramic sealer into dentin tubules activated by carriers

Abstract

The purpose of root canal obturation is to create a hermetic seal in the space where the pulp tissue was
previously located, thereby preventing the migration of microorganisms and ensuring periapical health. The
effectiveness of the obturation achieved is assessed by its ability to fill irregularities in the canal, the
appearance of gaps between the materials and the penetration of the dentinal tubule. The latter creates a
physical-mechanical closure, thus increasing retention, improving sealing and hindering microleakage
between the sealant mass and the canal walls. The aim of this study is to evaluate, using a confocal laser
microscope, the depth of penetration of the dentinal tubule of a tricalcium silicate-based sealer after
dispensing the cement with the XP-Endo Finisher instrument and other carriers, adding the obturation with
a gutta-percha cone using the single cone technique.
This research project was approved by the Comitê de Ética em Pesquisa da Universidade Federal do Rio
Grande do Sul (UFRGS). Fifty bovine teeth were used, cut using a metallographic machine to standardize
the samples at 12 mm in length, and their canals were prepared with a 50-gauge reciprocating instrument.
After preparation, and immediately after drying, a calcium silicate-based sealer was mixed with Fluo-3 dye.
For sealer placement, the roots were randomly distributed into five groups: Control, Lentulo,
EndoActivator, Ultrasonic, and XP-Endo Finisher (N=10). 7 days after filling, the apical third of each
sample was sectioned transversely into 2 mm slices corresponding to the apical thirds at 2 and 4 mm from
the apex. The samples were evaluated by Olympus Fluoview 100 confocal laser microscopy (Olympus
Corporation, Tokyo, Japan) with 559 nm wavelength light excitation. Images were recorded in fluorescent
mode, 10x magnification and numerical aperture of 0.3 and 1.3 mm respectively. The sealant penetration
area inside the dentinal tubule was generated by the images obtained in FluoView 10-ASW 4.2 software
(Olympus Corporation, Tokyo, Japan). Each image will be imported into Adobe Photoshop CC2018
software and then the Lasso tool will delimit and measure the sealer penetration area.