Gibson returned to action in the midweek win over West Brom after spending a month on the sidelines with a thigh injury.
The Irishman played for the final 25 minutes of the game, and is likely to feature again when Everton host Aston Villa on Saturday.
Moyes said: "It was important that we got him a bit of the game. We need him back to add to the numbers and he is in contention for a place.
"I'm glad to get him back out. I don't think we have got a lot of injuries but the minute we get one or two, it can make an indent on us.
"We are trying to keep as many of them fit and I have got to give them credit because they keep going."