Comparison of fluoridated apatites with pure hydroxyapatite as potential biomimetic alternatives to enamel for laboratory-based bond strength studies
Online veröffentlicht: 14. Dez. 2023
Seitenbereich: 12 - 18
Eingereicht: 01. Sept. 2008
Akzeptiert: 01. Jan. 2009
DOI: https://doi.org/10.2478/aoj-2009-0003
© 2009 Steven P. Jones et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
Aim
To investigate whether fluoridated apatites have a shear bond strength which more closely equates to that of natural enamel than pure hydroxyapatite, making them potentially useful as biomimetic alternatives to natural enamel for ex vivo laboratory bonding studies.
Methods
Discs of pure hydroxyapatite, pure fluorapatite and a 1:1 mixture of hydroxyapatite-fluorapatite were produced by cold uni-axial pressing. The discs were sintered at 1300°C, embedded in epoxy resin, ground and polished. X-ray diffraction technique was used to analyse the purity of the apatites. Scanning electron microscopy was employed to investigate the etch patterns of the apatite specimens. Ninety-six upper left central incisor brackets were bonded to each of the three groups of discs. Shear bond strengths were determined by debonding the brackets using a loaded metal jig in an Instron Universal Testing Machine. The sites of bond failure were recorded using the Adhesive Remnant Index. One-way analysis of variance (ANOVA) and Bonferroni post-hoc comparisons were used to determine statistical differences between the mean shear bond strengths of the three specimen groups.
Results
The mean shear bond strength of pure hydroxyapatite (20.44 MPa; SD: 8.03; 95% CI: 18.81, 22.07) was significantly higher than those of fluorapatite (13.13 MPa; SD: 6.76; 95% CI: 11.76, 14.50) and hydroxyapatitefluorapatite (13.62 MPa; SD: 7.03; 95% CI: 12.19, 15.04) (
Conclusion
Pure fluorapatite and hydroxyapatite-fluorapatite specimens offer no advantage over pure hydroxyapatite as a suitable artificial substrate for ex vivo bond strength testing.