Acquafresca joined on loan from Bologna, with Levante holding an option to buy the 25-year-old at the end of the season, while Vyntra has signed a deal until the summer of 2014 following his release from Panathinaikos.
Acquafresca told the club's website he is looking forward to joining their top-six push.
"I really wanted to get here," he said. "There have been some problems but in the end they were all resolved.
"I hope to score many goals. I know the club and have many friends that have played here, such as Massimo Volta and Marco Storari. I have not spoken to everyone but I am told this is a great club."
Vyntra, who has 18 caps for Greece, has joined after making more than 200 appearances for Pana since joining in 2004.
- Sports & Recreation