In the current study, specimens exhibited adhesive type failures in all groups, with the fracture occurring through the luting cement-dentin interface. A view of the control group is presented in Figure 1, which shows the resin that penetrated into the dentin. Resin tags within the dentin tissue were clear and long for the eugenol-free provisional cement and calcium hydroxide provisional especially cement groups, whereas they were absent for light-cured provisional cement group. This fact supports data that the reduced bond strength of luting cement to tooth surfaces resulted from the presence of provisional cement residues that were not completely removed before permanent cementation. Specimens for testing were prepared using human teeth.

The manufacturer��s instructions were followed carefully when PLVs were prepared to ensure that in vitro procedures were the same as those used clinically, but in the current study, neither thermal cycling nor mechanical stress was applied. In a previously published study, Paul and Sh?rer17 showed that considerable differences for the bond strength values could be obtained if dentin bonding agents were applied to a dry dentin surface vs. a dentin surface that was constantly kept under intrapulpal pressure. In the current study, materials were applied to dentin that was not under intrapulpal pressure. These factors may limit the direct application of the study results to in vivo situations. Moreover, only one type of dual polymerizing luting cement and one-step/self-etch adhesive system were used.

Different results may be found with different luting cements or with total etch adhesive systems. CONCLUSIONS In the present study, significant differences were apparent in provisional cement groups, with light cured provisional cement groups having the lowest shear bond strength values. As the permanent bonding of PLVs can be adversely affected, the provisional cement and cleaning technique should be carefully selected. Calcium hydroxide provisional cement and cleaning with a dental explorer are suggested, since, within the limitations of current study, this technique yielded a shear bond strength value nearest to that of the control group.
A mesiodens is a supernumerary tooth located in the maxillary central incisor region; the overall frequency of mesiodentes is between 0.15% and 1.9%.

1�C3 Mesiodentes appear with a higher frequency in man than in women Brefeldin_A with a 2:1 ratio.4 These teeth are frequently impacted with a solitary location between the 2 central incisors or as unilateral teeth. Bilateral mesiodentes occur in 13% of all cases.1 Mesiodentes are frequently associated with various craniofacial anomalies including cleft lip and palate, Gardner��s syndrome, Down syndrome and cleidocranial dysostosis.5 Conventional radiological explorations have been used in order to pinpoint its position and plan its treatment and surgical removal (periapical and occlusal radiographs).