All three were substituted during Saturday's 1-1 draw at Airdrie through injury, with MacLean's change being the substitution of a substitute having already replaced Toshney early in the second half.
Lee Miller says it is a chance for others within the Falkirk squad to stake a claim for a place in the second half of the season as the Boairns bosses ring the changes at the club.
Raffaele de Vita has alreadya rrived on loan and Falkirk are now awaiting clearance for the Italian midfielder to make his debut on Saturday.
Miller explained: "Dumbarton are a good outfit with good experience and I know a few of them. It will be toguh but we need to make the Falkirk Stadium a fortress. Hopefully the fans turn out and I'm sure we'll get a good support.
"All the guys who came off on Saturday are struggling. Louis Longridge is on crutches this week, we're not sure about the length of Lewis Toshney's injury but he'll miss the weekend for sure and Ross MacLean is struggling with his rib injury which is frustrating because we just need to wait with an injury like that.
"We have a squad there and need the boys to all pull together, step up and keep kicking on.
"We're looking to do a few things over the next week or two - we'll see what happens in terms of transfers. It's a chance at the moment for other boys in the squad to show what they can do and give us a headache going into the weekend's game in training, and in the game if they get their chance."
The Bairns drew 1-1 with Jim Duffy's side the last time they met which was also Ray McKinnon's final match as Falkirk manager.
On the Sons' last visit to The Falkirk Stadium the Bairns ran out 6-0 winners.