Effect of different bonding techniques on the debonding characteristics of ceramic brackets

Objective: To evaluate and compare shear bond strength and
debonding characteristics of ceramic brackets using different
bonding techniques. Materials and Methods: Ninety six premolar
teeth were randomly divided into six groups: 1) Transbond XT
with 5 seconds etch, 2) Transbond XT with 15 seconds etch,
3) Transbond XT with Transbond Plus Self – Etching Primer,
4) Vertise Flow with 5 seconds etch, 5) Vertise Flow with
15 seconds etch, 6) Vertise Flow with Transbond Plus
Self–Etching Primer. In each group 16 bracketed teeth with
Inspire Ice bracket, 8 of which were debonded by universal testing machine to determine the shear bond strength. The other 8 ceramic brackets were removed with plastic debonding plier. All teeth were examined under a stereomicroscope, the adhesive remnant index and bracket fracture were assessed. Results: The mean SBS for group I to VI was (1.78 ± 0.78, 14.5 ± 5, 12.52 ± 3.69, 4.15 ± 2.35, 13.26 ± 4.46, 6.78 ± 3.51,) MPa respectively. Bracket fractures were noted in 10 out of 48 samples after debonding with plier. Groups II and V exhibited the higest SBS and the highest ratio of bracket fracture. Conclusion: Using 15 seconds etching with either Transbond XT or Vertise Flow gave acceptable SBS. Self-etching primer gave lower SBS but within the acceptable clinical range. Decreasing etching time to 5 seconds didn’t give clinically acceptable SBS