The squad additions have been made ahead of England's autumn internationals against Fiji, Australia, South Africa and New Zealand in November.
The Northampton forwards both went off with knee problems during Saints' 16-6 Aviva Premiership defeat against Saracens at Franklin's Gardens.
With the extent of the injuries still to be assessed, England coach Stuart Lancaster thought it wise to call upon Paice - London Irish hooker, and Robson - Harlequins lock.
On Hartley and Lawes, Saints director of rugby Jim Mallinder said: "They've done something, but we will know a lot more later.
"They are the sort of characters that if they had just got a knock they wouldn't have come off."
Lancaster's 32-man squad assembled in Burton on Sunday. Their first game with Fiji is on 10 November 10, followed by Twickenham appointments with Australia, South Africa and New Zealand.
London Irish hooker Paice has two Test caps to his name while Harlequins lock
Robson will be hoping to impress in the senior set-up for the first time.
Hartley's injury will be a growing concern for Lancaster, with Harlequins' Joe Gray and Bath's Rob Webber currently on the sidelines, while Bath hooker Lee Mears recently retired from international rugby.
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