Shear bond strength of debonded ceramic restorations re-cemented by means of a cleaning and retreatment protocol

Abstract

Background As there is no standard method for re-cementing debonded partial ceramic restorations, the aim of this study was to evaluate the use of a non-invasive thermal protocol for cleaning and retreatment, and to study its influence on shear bond strength. Material and Methods Twenty ceramic samples (IPS e.max CAD®) were bonded to composite cement cylinders and underwent a shear bond strength test (G1, n=20). A second group was created (G2, n=20), representing debonded restorations. To simulate debonding, the samples were artificially contaminated with composite cement. After debonding, these underwent a thermal protocol to remove remaining adhesive. After rebonding to the composite cement cylinders, samples underwent the shear bond strength test. Results Median bond strengths for G1 and G2 were 7.28±3.23; 7.06±3.41 MPa, respectively, without significant difference between the groups ( p =0.983). Conclusions Debonded lithium disilicate glass-ceramic restorations should undergo a laboratory cleaning and retreatment protocol before being returned to the clinic for rebonding. Key words: Ceramic, adhesive debonding, shear bond strength, porcelain laminated veneers.

Influence of resin removal treatments on the surface topography and strength of de-bonded lithium disilicate ceramic

“…Cleaning the surface with heat or bur treatment followed by HFA and silanization is recommended. These recommendations are supported by Pineda-Vásquez et al 19 and Román-Rodríguez et al 15…”

“…Second, difficulty of differentiating between adhesive resin and ceramic because of similar color tone may compromise the LDC structure, making it weaker and prone to fracture. 19,24…”

“…28 The drawback with this type of treatment is that it is time-consuming and requires technical support from the laboratory for cleaning and retreatment procedures. 19…”

“…Moreover, limited studies are available assessing surface topography of LDC after retreatment of de-bonded restorations. 19,15 It is hypothesized that de-bonded LDC treated with different regimes (heat treatment, air abrasion, and diamond bur) will show significant difference in the surface topography and compressive strength of the material. Therefore, the aim of this study was to assess the influence of resin removal treatment regimes on the surface topography and compressive strength of de-bonded ceramic surfaces.…”

The efficiency of ErCr:YSGG laser on the debonding of different thicknesses of ceramic veneers

“…IPS Ceramic Etching Gel ® (4.9% hydrofluoric acid) (Ivoclar, Vivadent ® , Schaan, Liechtenstein) was applied to the internal surfaces of the discs (intaglio surface) for 20s. Then, disc specimens were rinsed and dried thoroughly with water spray and air respectively, then silane Monobond Plus ® (Ivoclar, Vivadent ® , Schaan, Liechtenstein) was applied to the internal surfaces of the discs for 60 s. and allowed to air dry 16,17 . Variolink Esthetic ® LC (shade light+) (Ivoclar, Vivadent ® , Schaan, Liechtenstein) resin-based cement was then applied to the internal surface of the disc which was seated into place on the prepared flat tooth surface under load by using a glass slide applied on the ceramic disc over which a load of 75 mg was applied for 1 minute.…”