Captain Sean Penkywicz, who only returned from a five week lay off with a broken hand in last weekend's 38-28 loss to Celtic Crusaders, is chief among Calland's concerns with a damaged jaw.
"Sean went for a big hit and took a bit of a bang," said Calland.
"He's loosened his wisdom teeth and there's an outside chance he's got some kind of fracture in there.
"He's booked in to see the dentist and we'll take it from there.
"I actually did something similar last year playing in the National Conference and the teeth came out with a bit of bone attached.
"It knocked me out for a day or so but I wasn't actually out of action for long."
Aside from Penkywicz, Calland had Paul Smith (knee), Shad Royston (leg), David Wrench (knee), Frank Watene (back), Richard Varkulis (ankle), Danny Heaton (ankle), Ben Black (leg), Joe Walsh (broken nose), Mark Flanagan (stomach) and James Haley (eye) lining up outside the treatment room last night.
"We had enough players for a game of three aside," laughed Calland.
"Some of them will pull through for Sunday, but a few of them could be struggling.
"Flanagan has torn a muscle in his stomach and Ben has a torn quad muscle, which he aggravated by playing with it against Celtic.
"We'll just have to sit down at the end of the week, assess things then and pick a team.
"It's not an ideal situation to be in, and I can't really believe our luck at the moment."

St Helens coach Daniel Anderson revealed he is close to finalising his Carnegie Challenge Cup final team to face a Hull side he describes as having been "pole-axed" in recent weeks.
Victory at Huddersfield this weekend will take the cup holders into next Saturday's Wembley showdown against the faltering Black and Whites on the back of a remarkable 20 straight wins.
Although forwards Nick Fozzard and Maurie Fa'asavalu look set to miss the match due to injury, Paul Sculthorpe and Sean Long should be passed fit to play.
Anderson said: "There are only really 18 blokes in contention - provided everyone is fit and healthy.
"If we lose some players then I'm confident about the blokes that we can bring in.
"But I don't think it's too hard to pick the top 18."
Prop Fozzard is working his way back towards full fitness after six months out with a ruptured cruciate knee ligament.
"Foz probably won't be ready for the final," said Anderson.
"He's improving - he'll play again this weekend against Huddersfield - and I'm sure he'll improve again.
"But he didn't get as many minutes as I would have liked against Harlequins last weekend and I always thought he would be more prominent for the play-offs."