Microleakage between composite/wire and composite/enamel interfaces of flexible spiral wire retainers: direct versus indirect application methods.
OBJECTIVE
The aim of this in vitro study was to compare the microleakage of flexible spiral wire retainers (FSWR) at composite/wire and composite/enamel interfaces produced by an indirect application method to that of a conventional direct application method.


METHODS
Forty freshly extracted human mandibular incisor teeth were randomly divided into two equal groups. Group 1 was bonded directly according to the manufacturer's recommendations. Group 2 consisted of 20 teeth bonded indirectly with Transbond LR as the adhesive and Sondhi Rapid Set A/B Primer (3M Unitek, Monrovia, CA, USA), a filled resin primer. After bonding, specimens were further sealed with nail varnish, stained with 0.5% basic fuchsine for 24 h, sectioned and examined under a stereomicroscope that measured microleakage at the composite/wire and composite/enamel interfaces from both mesial and distal margins. Statistical analyses were performed using Wilcoxon and Mann-Whitney U-tests with Bonferroni correction.


RESULTS
Statistical comparisons indicated that no statistically significant differences were observed between composite/wire and composite/enamel interfaces for direct vs. indirect application procedures (Direct method p = 0.630 and Indirect method p = 0.930). Comparisons of the microleakage scores between direct and indirect FSWR application groups at composite/wire and composite/enamel interfaces indicated no statistically significant microleakage differences at mesial or distal margins (Composite/enamel interface p = 0.361 and Composite/wire interface p = 0.270).


CONCLUSIONS
The type of FSWR application procedures (direct vs. indirect) did not significantly affect the amount of microleakage at the enamel/composite/wire complex.
Yagci
A
A
Department of Orthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey. dtahmetyagci@hotmail.com
Uysal
T
T
Ertas
H
H
Amasyali
M
M
D003188:Composite Resins; D001840:Dental Bonding / Q000379:methods*; D003763:Dental Leakage / Q000209:etiology*; D006801:Humans; D007180:Incisor; D015588:Observer Variation; D018704:Orthodontic Retainers / Q000009:adverse effects*; D009969:Orthodontic Wires / Q000009:adverse effects; D019279:Resin Cements; D018709:Statistics, Nonparametric
D003188:Composite Resins; D019279:Resin Cements; C481385:Transbond LR