Most common sinus to be involved in acute sinusitis?

Ans. is 'b' i.e., Maxillary Most common sinus affected by sinusitis overall Maxillary Most common sinus affected in adult Maxillary Most common sinus affected in children Ethmoid Least common sinus affected Sphenoid Sinuses involved in order of frequency Maxillary > Frontal > Ethmoid > Sphenoid