牙齒發生外傷後,通常會建議以下列何種藥品幫助受傷部位牙齦清潔?
2% chlorhexidine gluconate
0.2% chlorhexidine gluconate
3% \mathrm{H}_{2}\mathrm{O}_{2}
\mathrm{H}_{2}
\mathrm{O}_{2}
0.3% \mathrm{H}_{2}\mathrm{O}_{2}