This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

(1) To compare the effectiveness of different dental etchants for bonding fixed orthodontic appliances.

(2) To compare the effectiveness of self etching primers (Transbond Plus Self Etching Primer, 3M Unitek, Monrovia, Califi, etc) with conventional etchants (phosphoric acid, polyacrylic acid, maleic acid, etc) for bonding fixed orthodontic appliances.

Null hypotheses

H1: There is no difference in the effectiveness of different etchants for bonding orthodontic brackets to teeth in terms of whether of how often the brackets come off during treatment.
H2: There is no difference in the effectiveness of self etching primers, compared with conventional etchants, for bonding orthodontic brackets to teeth in terms of whether of how often the brackets come off during treatment.