Can I keep this cat?

This male cat has been roaming the neighborhood since last October 2016. I’ve been caring for it with food, water and shelter.

I call him “Maui” because he has an island of grey fur on his back that is similar in shape to the Hawaiian Island of Maui.

I tried to contact its owners to no avail with posters in my area.

I can understand why someone would abandon this cat as he seems to have a bi-polar personality. He will be very friendly and the suddenly viciously turn on you with teeth and claws. I had to seek medical attention 3 weeks ago for a very serious bite he made on my hand. But I think that his odd behavior may be due to him being in pain from bad teeth (One canine tooth is broken in half).

Since no one has claimed this cat I plan on doing the following:

1. Medical examination including all required vaccinations.
2. Teeth cleaning and very needed dental work.
3. Nueter.
4. ID chip inserted in the back of it’s neck under the skin.

Despite his weird behavior I believe that Maui and I have developed a friendly bond. He is showing less aggression and more affection and I want to keep him.

Do you think that I’m doing the right things?