There was insufficient evidence to assess the effect of bonding modality on demineralization rates .
CONCLUSIONS There is weak evidence indicating higher odds of failure with self-etch primer than acid etch over 12 months in orthodontic patients , and there is strong evidence that a self-etch primer is likely to result in a modest time savings ( 8 minutes for full bonding ) compared with acid etch
INTRODUCTION The use of self-etch primers has increased steadily because of their time savings and greater simplicity ; however , overall benefits and potential disadvantages and harms have not been assessed systematic ally .
In this study , we review ed r and omized controlled trials to assess the risk of attachment failure , bonding time , and demineralization adjacent to attachments between 1-stage ( self-etch ) and 2-stage ( acid etch ) bonding in orthodontic patients over a minimum follow-up period of 12 months .
A randomised clinical trial to investigate bond failure rates using a self-etching primer.
This clinical trial evaluated , over a 12-month period , the performance of brackets bonded to teeth etched and primed with Transbond Plus Self-Etching Primer ( SEP ) when compared with a conventional separate two-step etch and primer system .  Thirty-nine r and omly selected patients requiring fixed appliance therapy were entered into the study . R and om allocation of each etching system , along with a ' split-mouth cross-quadrant ' design was used . A total of 661 brackets were placed by two operators . The failure and survival rates of the brackets were determined for age and gender of the patients , each etching system , operator , mode of failure , tooth position in the dental arch , and number of manipulations prior to curing the adhesive . Statistical analysis showed that SEP had a significantly higher bond failure rate ( 11.2 per cent ) than the conventional etch and primer system ( 3.9 per cent ) at the P = 0.001 level . Cox 's proportional hazards regression showed the conventional etch and primer system to have a 60 per cent reduced chance of bracket failure over a 12-month observation period , while males had a 2.4 times increased risk compared with females . The predominant mode of failure was at the composite enamel interface for the SEP , while for the conventional etch and primer system , it was within the composite adhesive . No statistically significant differences were found for the failure rate with respect to the age of the patient , operator , tooth location , or the number of manipulations of the bracket . This in vivo study showed that brackets bonded using SEP had an increased clinical bond failure rate compared with the conventional , separate , etch and prime system
There was insufficient evidence to assess the effect of bonding modality on demineralization rates .
CONCLUSIONS There is weak evidence indicating higher odds of failure with self-etch primer than acid etch over 12 months in orthodontic patients , and there is strong evidence that a self-etch primer is likely to result in a modest time savings ( 8 minutes for full bonding ) compared with acid etch
INTRODUCTION The use of self-etch primers has increased steadily because of their time savings and greater simplicity ; however , overall benefits and potential disadvantages and harms have not been assessed systematic ally .
In this study , we review ed r and omized controlled trials to assess the risk of attachment failure , bonding time , and demineralization adjacent to attachments between 1-stage ( self-etch ) and 2-stage ( acid etch ) bonding in orthodontic patients over a minimum follow-up period of 12 months .