Search

Objective: A long-term comparison of the failure rates of orthodontic brackets bonded with either a self-etching primer (SEP) or conventional etch and primer (AE). Design: Prospective randomized controlled clinical trial. Setting. UK district general hospital with one operator, 2003-6. Participants: Hospital waiting list patients needing fixed appliances (n=60). Method: Experimental (SEP) group patients (n=30) received pre-adjusted edgewise brackets (n=438) bonded with Transbond Plus following manufacturer's instructions. Control (AE) group patients (n=30, brackets n-433) were bonded using a 15- second conventional etch and primer (Transbond XI). In both groups brackets were light-cured for 20 seconds. First-time bond failures were recorded with the time of failure. Bracket bonding time was recorded. All patients were followed to the end or discontinuation of treatment. Results: Bracket failure rates: SEP=4.8%, AE=3.5%, P=0.793. Mean placement time per bracket (seconds): SEP=75.5 (± 6.7; 95% CI=72.9, 78.0), AE=97.7 (±9.1; 95% CI=94.3, 101.2) P=0.000. Conclusion: There was no difference in the failure rates of brackets bonded with either Transbond Plus SEP or conventional AE using Transbond XT paste. Bonding with SEP was significantly faster than using conventional AE. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinical failure rates of bonded first molar tubes with those of cemented bands during fixed appliance therapy. Design: Prospective randomized controlled clinical trial. Setting: Two UK hospital orthodontic clinics, February 2001-December 2004. Participants: Hospital waiting list patients needing fixed appliances (n= 110). Method: Patients were randomly allocated to two groups. Experimental group patients (n=55) received single first molar tubes (n=181) bonded with a no-mix chemically cured composite (Rely-A-Bond) after a 30-second etch. Control group patients (n=55) were treated with bands (n= 186) cemented with Intact glass ionomer cement (GIC). First-time failures were recorded together with the time of failure. All patients were followed to the end or discontinuation of treatment. Results: First-time failures: bands= 18.8%; bonds=33.7 %. Bonded tubes were more likely to fail [RR 2.4; 95% CI (1.4, 4.1)] compared with bands. Experimental group patients also had more bracket failures (P=0.009), when analysed at patient level. Conclusion: First molar tubes bonded with Rely-A-Bond composite showed a significantly higher first-time failure rate than bands cemented with Intact GIC. [ABSTRACT FROM AUTHOR]