Scalped grass will eventually grow back but it can take awhile.
Sometimes you may need to reseed the grass where you scalped the grass especially if the grass was too severely scalped.
Sometimes I'll scalp grass by accident and then I'll just throw some more grass seed onto the scalped area and within a few months or so the grass has grown back.
If you scalp the grass you should also water the lawn deeply but gently a few times per week which can also help encourage the grass to grow back after being scalped.
You can also apply some chelated iron or fertilizer to your scalped lawn which will also help the grass grow back.