Keeping this in consideration, how do you repair a damaged tree trunk?
To repair this type of damage, cut off any ragged bark edges with a sharp knife. Take care not to remove any healthy bark and expose more live tissue than necessary. If possible, the wound should be shaped like an elongated oval, with the long axis running vertically along the trunk or limb.
Similarly, should I seal a tree wound?
Tree sealants (tar, paints, shellac, etc.; ) do not prevent disease, decay, insect infestations or promote closing of wounds. There is actually some evidence that such sealants may actually cause harm. Leave wounds open and allow the tree's natural defenses to work as intended.
A tree's bark is like our skin. If it comes off, it exposes the inner layer of live tissue to disease and insect infestation. It does not grow back. A tree will heal around the edges of the wound to prevent further injury or disease, but it will not grow back over a large area.