Green contested the charge and, after hearing detailed evidence from an independent expert in oral pathology and forensic odontology, the citing was dismissed by the panel comprising chair Ian Unsworth QC, John Greenwood and Tony Wheat.
"The panel accepted that Rob Webber genuinely and honestly believed that he had been bitten. However, he did not see it due to the respective player's body positions nor was there any other eye witness to it," a statement from the RFU said.
"While the video evidence undoubtedly showed that Calum Green's mouth area was either in contact with or close proximity to Rob Webber's forearm, it was accepted by all that the footage did not show an actual bite take place.
"In those circumstances the panel was duty bound to accept that there was insufficient evidence to uphold the citing. The case was therefore dismissed and Calum Green was entitled to leave the hearing without a stain on his character."
Green is now free to immediately resume playing for Newcastle, who face Saracens in the Premiership on Saturday.
(Reporting by Hardik Vyas in Bengaluru; Editing by Christian Radnedge)
