Niobium pentoxide as a new filler for methacrylate-based root canal sealers
Article first published online: 11 AUG 2012
© 2012 International Endodontic Journal
International Endodontic Journal
Volume 46, Issue 3, pages 205–210, March 2013
How to Cite
Niobium pentoxide as a new filler for methacrylate-based root canal sealers. International Endodontic Journal., 00: 000–000, 2012., , , , , , .
- Issue published online: 10 FEB 2013
- Article first published online: 11 AUG 2012
- Accepted manuscript online: 9 JUL 2012 08:40AM EST
- Manuscript Accepted: 3 JUL 2012
- Manuscript Received: 6 MAR 2012
- Cordenação de Aperfeiçoamento de Pessoal de Nível Superior
- Companhia Brasileira de Metalurgia e Mineração
- degree of conversion;
- niobium pentoxide;
- root canal sealer
To evaluate the influence of several niobium pentoxide (Nb2O5) concentrations on the radio-opacity, flow, film thickness, microhardness and degree of conversion of an experimental root canal sealer.
An experimental dual-cured root canal sealer was produced with a methacrylate-based comonomer blend. Nb2O5 was added at four different concentrations: 0, 80, 100 and 120 wt%. Radio-opacity was evaluated according to ISO 6876 using a digital system (n = 5). Flow and film thickness were determined in accordance with ISO 6876 (n = 3). Microhardness was evaluated with 50 g for 15 s (n = 5). Degree of conversion was evaluated with FTIR immediately after photocuring and after 1, 7 and 14 days. The data were analysed using anova and Tukey's test. The degree of conversion over time was evaluated using RM-anova (α = 0.05).
The groups with 80 wt% and 100 wt% of filler showed no significant difference in radio-opacity from that of equivalent 2 mmAl (P > 0.05). The addition of 120 wt% resulted in radio-opacity values higher than 2 mmAl (P < 0.05). The flow was not significantly different amongst the different groups (P > 0.05). All groups had a film thickness of <50 μm (ISO 6876). All groups with Nb2O5 were associated with higher values of microhardness than the control group. The group with 0 wt% was associated with a higher degree of conversion at all times. All groups except those with 80 wt% had higher values for degree of conversion after 14 days than immediately after photocuring.
The addition of Nb2O5 increases radio-opacity and microhardness; this material may be a promising filler for the production of a new endodontic sealer.