Thanks for asking the query,
Tooth sensitivity after composite restoration mostly depends upon the cavity depth and the type of dentine bonding agent.
Restoration with shallow or medium depth cavity usually have less sensitivity.
Crackers are sticky substances due to improper bonding between tooth and the restoration creates pressure and sensitivity in the tooth.
There should be presence of protective layer of calcium hydroxide base to give pulpal protection in cases of increased depth of cavities.
I would suggest you to remove the restoration and place zinc oxide
eugenol dressing for a week and repeat the procedure by giving a layer of calcium hydroxide.
Hope this helps out.