Leakage values differed greatly amongst the materials tested (Table 4, Fig. 2). Amongst the five groups of materials tested, Fermin showed the least microleakage and a consistent leakage score of 3 in all the experimental conditions. It was followed by Caviton, Cavit and both groups of Canseal. Interestingly, both groups of Canseal presented severe microleakage scores after thermal cycling and thermal-load cycling.
Figure 3 shows the leakage of the test materials under different conditions. Dye penetration into the material was noted in Fermin (Fig. 3a), Caviton and Cavit (Fig. 3b) groups. This was not observed in the two groups of Canseal tested. Canseal in control and load cycling groups presented a nearly perfect seal. However, all Canseal specimens exhibited total leakage notably after being subjected to thermal cycling and thermal-load cycling (Fig. 3c).
Figure 2. Mean grades of dye penetration of test materials.
Figure 3. a. Fermin exhibiting grade 3 dye penetration after thermal cycling.
b. Cavit exhibiting grade 2 dye penetration after load cycling.
c. Canseal 1 exhibiting grade 1 dye penetration after thermal cycling.
No statistically significant difference was noted in the microleakage scores between Canseal 1 (powder to liquid ratio = 0.2 g to 2 drops) and Canseal 2 (powder to liquid ratio = 0.4 g to 2 drops) as well as between Fermin and Caviton (Table 5). Likewise, no significant difference was noted in the scores between load cycling and control groups, and between thermal cycling and thermal-load cycling groups (Table 6).
Table 5. Fisher's post hoc values for materials (P < 0.05).
Table 6.Fisher's post hoc values for conditions (P < 0.05)