Centre de Santé, 16 rue du Petit Albi, 95520 Osny, France
Unité de Recherche en Biomatériaux Innovants et Interfaces (URB2i), UR 4462, Faculté de chirurgie dentaire, Université de Paris, 1 rue Maurice Arnoux, 92120 Montrouge, France
Hôpital Pitié-Salpêtrière, 47-83 boulevard de l’Hôpital, 75013 Paris, France
Hôpital Bretonneau, 23 rue Joseph de Maistre, 75018 Paris, France
Hôpital Henri Mondor, 1 rue Gustave Eiffel, 94000 Créteil, France
Hôpital Charles Foix, 7 avenue de la République, 94200 Ivry-sur-Seine, France
Introduction:The number of adult patients who seek an orthodontic treatment is increasing. These patients often have lithium disilicate ceramic restorations. The orthodontist has to find a procedure to bond effectively brackets to these restorations. In 2011, a new family of adhesives was introduced, universal adhesives, which are capable of bonding to ceramic and are said “multi-mode” because they can be used in etching-rinse or self-etching protocol on tooth surface. The objective of this in vitro study was to evaluate the shear bond strength (SBS) of metal brackets to lithium disilicate ceramic support using a universal adhesive. Materiels and Methods: Forty machinable lithium disilicate blocks (IPS e.max CAD, Ivoclar) were prepared according manufacturer’s instructions. Each specimen was randomly assigned to one of four groups (n=9 or 10) defined by the pretreatment protocol. Protocol 1: Hydrofluoric Acid 9 % (HF) + Silane + Orthodontic adhesive (Transbond™ XT Light Cure Adhesive Primer, 3M ESPE), protocol 2: HF + Universal adhesive (UA) (Scotchbond Universal®, 3M ESPE), protocol 3: UA only, protocol 4 : Monobond Etch & Prime® (Ivoclar) + UA. Then, a bracket of upper cuspid (3M ESPE) was bonded to each specimen with a composite resin (Transbond™ XT, 3M ESPE). SBS was measured between ceramic and bracket with a universal testing machine. A one-way ANOVA (ANalysis Of Variance) followed by Tukey’s post-hoc test was performed to investigate SBS differences between groups. Results: Protocol 2 (43 MPa) and protocol 4 (36 MPa) showed the highest SBS values and were statistically different from protocol 1 (25 MPa) and protocol 3 (21 MPa). Conclusion: Despite the lower bond values obtained in the study, but higher than the minimum expected, the application of UA alone appears to be a safe procedure that seems to provide sufficiently strong and resistant bonding between the ceramic and the bracket. However, clinical studies are needed before a recommendation can be made.