Straight on view of composite contact Occlusal view of composite contact
Contact area still has a gloss in spite of the purposely over etched opposing tooth enamel. This is why the bond is easily broken with a spatula. There was no harm done to the opposing tooth enamel. The etched area will re-mineralize. The contact is not vulnerable to caries because Class II caries occur below the tooth to tooth contact for an obvious reason. This is where the plaque accumulates.
Competed restoration Contact as width and depth. It is tight and smooth. Contact will prevent food impaction