The Effect of 35% Carbamide Peroxide Strength of Lithium Disilicate Faced Zirconia Dental Restoration: A Pilot Study
Carbamide Peroxide, Home Bleach, Lithium Disilicate, Shear bond strength, Zirconia, zirconia Veneer
AuthorsABSTRACTObjective: The purpose of the paper was to study the influence of 35% Carbamide Peroxide (CP) external coat on the shear bond strength (SBS) of the lithium disilicate veneered zirconia restoration. This work investigates whether the bleaching is possible for such a restoration without leading to future failure. Materials and Method: A total of 20 specimens were fabricated in this pitot study. The specimens were subdivided into two groups: 10 specimens without bleaching coat and the other 10 specimens were coated with 35% CP whitening gel. Result: The mean value of the SBS showed the highest bond was represented in the group of bleached specimens (191). While, Mann-Whitney U test (nonparametric test) showed that the p-value for the two groups is not significant (p-value 0.172), means that there is no clear difference in the shear bond. Conclusion: The pilot study revealed that there is an increase in the mean value of SBS between zirconia and lithium disilicate in the treated group but considered as a non-significant difference. SEM showed a clear surface change in the bleached veneering material which might enhanced the bonding strength with the core.
INTRODUCTIONWith a social media invasion and the increased beauty advertisings through celebrities and famous actors, the people interest about teeth whitening has become important as one of the beauty standards. Many patients choose bleaching treatment for esthetical reasons. Some of them want whiter teeth. Whereas, elimination of the intrinsic discoloration was the choice of the others. Such discolorations caused by smoking, drinking tea, coffee or red wine [1]. For treating discolored teeth, popular materials were used, such as Hydrogen Peroxide (HP) and CP or Sodium Perborate (SPB) [2]. The same active ingredient can be used in home bleaching kits at concentrations of 10%-15% or in-office at a concentration of 35%. Higher concentrations can cause more harm to the essential pulpal tissues and accelerate diffusion. Because it combines pulp safety and whitening efficiency, low concentrated agent home bleaching has gained popularity since its launch in the 1990s. Those patients with replaced teeth prefer all-ceramic over porcelain fused to metal restorations, and this evidence has been given by a large number of available studies [3,4,5]. They considered as a good alternative to PFM crowns/bridges [6] and clinical results were provided by Etman and Woolford [7,8]. Although, all- ceramic materials are considered as high-strength, naturalcolored materials for dental restorations. Yet, color matching between restorative materials and tooth still remains a challenging matter as the optical properties of the natural teeth cannot be preserved due to darkening with older ages [9]. Although bleaching solutions are intended to be used to whiten natural teeth, they may unintentionally come into touch with dental materials used to restore teeth in the aesthetic area. ••••••••••••••••••••••••••••••• ejprd.org - Published by Riset Publishing Services LLC
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