Results: A significant difference (p < 0.001) of mean debonding force was found between different types of teeth in vivo. Clinically, ARI scores were not significantly different (p = 0.921) between different groups, but overall higher scores were predominant.
Conclusion: Bracket debonding force should be measured on the same tooth from the same arch as the significant difference of mean debonding force exists between similar teeth of the upper and lower arches. The insignificant bracket failure pattern with higher ARI scores confirms less enamel damage irrespective of tooth types.
AIM: To evaluate the shear bond strength of Zinc phosphate cement Elite, glass ionomer cement Fuji I, resin-modified glass ionomer cement Fuji Plus and resin luting cement Panavia-F to Turkom-Cera all-ceramic material.
MATERIALS AND METHODS: Turkom-Cera was used to form discs 10mm in diameter and 3 mm in thickness (n = 40). The ceramic discs were wet ground, air - particle abraded with 50 - μm aluminium oxide particles and randomly divided into four groups (n = 10). The luting cement was bonded to Turkom-Cera discs as per manufacturer instructions. The shear bond strengths were determined using the universal testing machine at a crosshead speed of 0.5 mm/min. The data were analysed using the tests One Way ANOVA, the nonparametric Kruskal - Wallis test and Mann - Whitney Post hoc test.
RESULTS: The shear bond strength of the Elite, Fuji I, Fuji Plus and Panavia F groups were: 0.92 ± 0.42, 2.04 ± 0.78, 4.37 ± 1.18, and 16.42 ± 3.38 MPa, respectively. There was the statistically significant difference between the four luting cement tested (p < 0.05).
CONCLUSION: the phosphate-containing resin cement Panavia-F exhibited shear bond strength value significantly higher than all materials tested.
Materials and Methods: One hundred and sixty endodontically treated maxillary central incisors embedded in acrylic resin with decoronated root portion were taken for the study. The postspaces were prepared according to standard protocol. The samples were divided into two groups according to the post material: glass-fiber post and Quartz fiber post. These groups were further subdivided on the basis of coronal extension of 4 and 6 mm for glass fiber and Quartz fiber posts, respectively. The posts were then luted with dual-polymerizing resin cement followed by core buildup. Samples were subjected to increasing compressive oblique load until fracture occurred in a universal testing machine. Data were analyzed with one-way ANOVA and independent Student's t-test. Analysis was done using SPSS version 15 (SPSS Inc., Chicago, IL, USA) Windows software program.
Results: Glass fiber post with coronal extension of 4 mm (182.8 N) showed better results than with 6-mm length (124.1 N). Similarly, in quartz fiber posts group, 4-mm postlength (314 N) was better when compared with 6 mm (160 N). The 4-mm coronal extension of quartz fiber post displayed superior fracture resistance.
Conclusions: Glass fiber posts showed better fracture resistance than Quartz fiber posts. 4-mm coronal length showed more fracture resistance than 6 mm.