TITLE:
Bonding Orthodontic Ceramic Brackets to Ceramic Restorations: Evaluation of Different Surface Conditioning Methods
AUTHORS:
Andreas Faltermeier, Claudia Reicheneder, Peter Götzfried, Peter Proff
KEYWORDS:
Ceramic Restorations; Ceramic Brackets; Aluminium Trioxide; Orthophosphoric Acid
JOURNAL NAME:
Materials Sciences and Applications,
Vol.4 No.7B,
July
18,
2013
ABSTRACT:
The purpose of this study was to compare the shear bond strength and Adhesive Remnant Index of four different veneering ceramic materials to ceramic brackets. Additionallly, a further aim of this study was to overcome the etching using hydrofluoric acid which is noxious and could seriously damage the corneas of the eyes. Two surface conditioning methods of four ceramic materials before bonding brackets were examined: in group 1 an air particle abrasion with 25 μm aluminium trioxide (4 seconds at a pressure of 2.5 bars) and subsequently a silane coupling agent (Espe Sil, 3M Unitek, Monrovia, USA) was applicated on one side of each ceramic specimen (10 per group). In group 2 one side of each sample (20 per group) was etched with 37.0 per cent orthophosphoric acid for two minutes and was followed by a silane application (Espe Sil, 3M Unitek, Monrovia, USA). After this procedure the self-ligating ceramic brackets Clarity SL (3M Unitek, Monrovia, USA) brackets were bonded to the ceramic blocks and a thermocycling process started (5°C - 55°C, 6000 cycles). Then, shear bond strength and Adhesive Remnant Index (ARI) were measured. To determine statistical differences Oneway-ANOVA and Tukey Post-hoc test were performed. Hydrofluoric acid seems not to be justifiable anymore for preparing the surface of dental ceramic restorations before bracket bonding. Sandblasting with 25 μm aluminium trioxide and the use of orthophosphoric acid (37.0 per cent) seem to prepare the surface of ceramic restoration sufficiently before ceramic bracket bonding. The found level of shear bond strength values seems to be sufficient for bonding ceramic brackets to ceramic restorations.