تقييم مدى مقاومة إسمنت الزجاج المدعوم بالراتنج لقوى القص بالمقارنة بالراتنج ذاتي التصلب و الراتنج ضوئي التصلب

Abstract EN

Resin-reinforced glass ionomer cements have been developed and marketed for cementing orthodontic brackets to teeth.

These include the release of fluoride with its known caries-inhibiting properties.

Aim: The purpose of this study was to evaluate the resin-reinforced glass ionomer cement resistance for shear strength and to compare it with self cured and light cured resin adhesive and determine failure mode.

Material and methods: Thirty extracted human premolars were randomly divided into 3groups.

Stainless steel brackets were bonded on the buccal surfaces with 1 of 3 systems: group 1, no-mix chemically cured adhesive (Unite) (n= 10); group 2, light-cured adhesive (Transbond XT) (n = 10).

Group 3, resinreinforced glass ionomer cement (Fuji Ortho LC ) without enamel etching in moist condition.

The specimens were stored in distilled water for 24 hours at 4 °C.

Brackets were debonded using an Instron machine.

Shear bond strength values were recorded.

Results: The mean bond strengths (in megapascals) were (11.32) in group 1, (8.59) in group 2, and (5.08) in group 3.

ANOVA and Bonferroni test showed a statistically significant (P=.017) difference in mean bond strengths between group 1 and 3 whereas the difference between group 2 and 3 and between group 1 and 2 was not statistically significant.

The site of bond failure was between bracket and adhesive in the two adhesive resin and between adhesive and enamel in the resin-reinforced glass ionomer cement.

The comparison of the Adhesive Remnant Index scores indicated that there were significant difference in failure mode between the two resin adhesive and resin-reinforced glass ionomer cement.

Conclusions: Resin-reinforced glass ionomer cement without enamel etching in moist condition showed bond strength lower than the two resin.

Clinically, these products may be not suitable for orthodontic bracket bonding .