Dembele was not included in PSG’s squad which travelled to London after he was involved in a bust-up with Luis Enrique.
PSG went on to lose at the Emirates Stadium, with Arsenal securing a 2-0 win through first-half goals from Kai Havertz and Bukayo Saka.
Luis Enrique has faced criticism over his decision to omit Dembele from PSG’s Champions League tie and Saliba believes the winger’s absence was a positive for Arsenal’s players.
Asked about Dembele’s situation at PSG this week, Saliba told Canal Plus: ‘It did us good when we learned that he wasn’t there.
‘But we know that they have other players to make up for his absence. We focused on ourselves, but of course, his absence could have done us good.’
Saliba also said: ‘Today, we deserve this victory.
‘The coach had said that in both areas, we had to be better than them. And that’s what we did today. As soon as we had a few chances, we put them in the back of the net.
‘It was 2-0 at half-time and even when we weren’t doing well, we were able to defend well together. I think we deserve this victory.’
Meanwhile, former Arsenal midfielder Samir Nasri criticised Luis Enrique’s handling of the situation with Dembele.
‘They put him on the bench, they already took his ethics bonus away, that was enough of a punishment,’ Nasri told Canal Plus.
‘To me, pushing him aside is shooting yourself in the foot.
‘We can say what we want… yes, he wastes some time in his final move, but he makes so much difference. And his understanding with Achraf Hakimi brings so much to this team.
‘For me, Luis Enrique wants to assert his authority too much with this decision. He didn’t have to go that far.’