How Do You Remove Grid Embedded In Scanned Image?

If you create a graphite drawing on paper using a grid that you drew on the same paper, how can you remove the grid in Photoshop and refill the gaps from where the grid was at? In general, how can you remove a grid embedded in a scanned image of a drawing or photo in Photoshop? And how do you refill the gaps or missing details after the removal of the grid? Also, what if the grid is very light, very dark or mixed colors? And what if the grid lines are very thin? Please show visual examples of your solutions. Thank you.