Objectives:
Evaluation of the shear bond strength of conventional capsulated glass-ionomer cements to bovine dentine after Heal Ozone treatment.
Methods:
60 extracted bovine teeth were prepared by removing enamel to expose the dentine. The 20 teeth in group A were treated with Heal Ozone (KaVo, Germany) then conditioned with conditioner (GC International). The 20 teeth in group B were treated with Heal Ozone and Ozone-Reductant(KaVo, Germany) and then similarly conditioned. Group C (controls) were only conditioned. 20 cylindrical samples of glass ionomer Fuji Fast (GC International-X) and 20 similar samples of Ketac Molar Aplicap (3M-ESPE, Seefeld, Germany-Y) were bonded to the prepared surfaces. The teeth were stored in high humidity at 37oC for 24 h and tested for shear bond strength using a Hounsfield Universal Testing Machine. The statistical analysis was performed using the Newman-Keuls test.
Results:
| Group | Cement | SBS/MPa | SD/MPa |
| A B C |
X
| 1.9 4.1 3.9 | 1.2 1.6 2.1 |
| A B C |
Y
| 1.1 2.9 2.8 | 0.5 0.7 1.6 |
Conclusions:
Group A gave the lowest values of SBS in both cases though this was statistically significant (p<0.05) only for cement Y. There was no statistical difference between group B and the control group. Heal Ozone treatment alone thus has a tendency to weaken the SBS of glass-ionomers bonded to bovine enamel, but this is eliminated by the use of Ozone Reductant.