3.8. CONDITIONING
Etchant Gel S is applied by drops to all enamel and dentine areas that are to be bonded and spread evenly
with a brush to the cervical limit without additionally irritating the gingival region. The setting time on the
enamel is 30-60 s, on the dentine 15 s and it is then sprayed for 20 s. There must be no blue traces on the
enamel or the dentine. Excess water is removed with the air blower.
NOTE
Allow Etchant Gel S to cure for 60 s on convex bevels. The outermost bevel areas end up in superficial enamel
zones, which are less soluble, even though they have been ground. Etching times less than 60 s cause increased
dissolution from bevels; etching times over 60 s do not have any advantages with reference to adhesion force
and marginal morphology. The major factor is the result of the etching, i.e. adequately etched enamel loses gloss
and appear frosty-white. Repeat in case of doubt. Unprepared, fluoride-rich enamel must be etched for a longer
period (120 s).
Do not dry dentine areas with air, this may cause collapse of the exposed collagen layer and reduce the ad-
hesion force.
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