Hydrofluoric Acid Etching Ceramic

Spearman s coefficient rs indicated strong and significant correlation between machining order and roughness rsra 0 66.

Hydrofluoric acid etching ceramic.

13 this matrix is selectively dissolved and its crystal microstructures are exposed. 14 15 resulting in a rough ceramic surface that provides increased micromechanical retention with the resin cement. Sbs of resin cement multilink n ivoclar vivadent to ceramic. Etching with 4 8 hydrofluoric acid followed by monobond plus hfmp monobond etch prime ivoclar vivadent mep no treatment nt as negative control and monobond plus ivoclar vivadent with no etching mp as positive control.

The ceramic post machining surface roughness differed significantly according to the pair of burs employed p 0 05. Most refinishers use hydrofluoric acid to chemically etch a porcelain or ceramic tile surface in an attempt to make their coating stick hydrofluoric acid is so strong that it actually eats away the porcelain creating pits and a rough area for the new coating to hold onto. 40 rectangular discs from each ceramic material ips e max cad em vita mark ii vm vita enamic ve were equally divided n 10 and assigned to one of four surface pretreatment methods. A clinical study showed the importance of bonding where acid etching of glass ceramic.

The procedure involves acid conditioning using hydrofluoric acid hf and the application of a silane primer. Before cementation all glass ceramic surfaces must be etched using hydrofluoric acid hf for increase of surface roughness sr and surface free energy sfe. Ceramic bar shaped specimens 16 mm x 2 mm x 2 mm were produced from ceramic blocks. Hydrofluoric acid etching followed by silanization generates higher bond strengths than either treatment alone.

Effect of hydrofluoric acid concentration and etching time on bond strength to lithium disilicate glass ceramic. Groups b e were etched with 4 9 hydrofluoric acid hf. In vitro studies have reported positive effects of hydrofluoric acid hf etching on the strength of glasses by removing or stabilizing surface defects and on surface topography increasing roughness for adhesive bonding 2 8 9. On the other hand hf etching can weaken the flexural strength of ceramics 10.

For 1 and 2 5 hf the etching times from 40 to 120 seconds increased the μsbs values compared with 20 seconds p 0 05 but etching periods did not differ within the 5 7 5 and 10 hf groups p 0 05. All specimens were polished and sonically cleaned in specimens were randomly divided into 5 groups n 15. Silanization is understood to create hydrogen bonding and covalent bonding between the resin and the ceramic and increased wettability of the ceramic surface while etching provides the mechanical interlocking 4 9. 14 16 in addition the increased.

The aim of this study was to evaluate the influence of different concentrations of hydrofluoric acid hf associated with varied etching times on the microshear bond strength μsbs of a resin cement to a lithium disilicate glass ceramic.