Fig. 2
From: Impact of mucosal biofilm and bony osteitis on chronic rhinosinusitis with nasal polyps
a Bone grade I with periosteal thickening (arrow). b Bone grade II with periosteal thickening (star) and osteoblastic activity (arrow). c Bone grade II with osteoblastic and osteoclastic activity (arrow). d Bone grade III with irregular wide bony trabeculae (arrow)
