Electric Toothbrush Abrasions

Receeding Gum Filling?

In the past 12 months I have had some ‘compound’ put into a gap between one of my upper molars for what my Dentist calls ‘toothbrush abrasion’. The gap is like a small slit where the gum-line meets the tooth. Today it (the compound) fell out again! Is there an alternative treatment that I could ask my Dentist about? I don’t have any pain from the tooth but I just want to be careful with it! Also…electric or manual tooth brush?

A small tooth-colored composite bonded to this small defect will resolve the problem.
This abrasion happend due to either brushing too hard or with any other bristles except soft ones.
Electic toothbrushes only come with soft bristles and are more thorough than manual.