Nanoleakage At The Zirconomer Improved-Dentin Interface After Incorporation of Nano-Hydroxyapatite: An In-Vitro Study And Implications For Pediatric Dentistry

Abstract

Objective: To compare nanoleakage at the dentin-restorative interface of Zirconomer Improved with and without incorporation of 5% w/w nano-hydroxyapatite (n-HA).

Materials and Methods: Thirty-two extracted human premolars were prepared and restored with Zirconomer Improved either without n-HA or after incorporation of 5% w/w n-HA. The modified powder was homogenized by planetary ball milling. After 1000 thermocycles between 5 °C and 55 °C, specimens were sectioned, exposed to 50% ammoniacal silver nitrate for 24 h, developed under fluorescent light, and examined by environmental scanning electron microscopy (ESEM) with backscattered-electron imaging and energy-dispersive X-ray spectroscopy (EDX). Sixteen specimens were reported per group. Nanoleakage was expressed as silver weight percentage.

Results: Mean silver weight was 3.08 ± 0.59% for Zirconomer Improved without n-HA and 1.86 ± 0.56% for the n-HA-modified material. The mean difference was 1.22% (95% CI, 0.23 to 2.21), with a statistically significant difference (p = 0.030).

Conclusion: Under the conditions of this in vitro experiment, the group receiving Zirconomer Improved powder modified with 5% w/w n-HA showed lower EDX-derived silver signal than the unmodified control.