Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Sinus ostia
Introduction
A sinus ostium (plural: sinus ostia) is the opening that connects a sinus to the nasal cavity itself. It is a tight area that tends to have a higher percentage of cilia than the surrounding mucosa.
If the sinus ostium is blocked, the entire sinus thus becomes the pathologic cavity or cystlike lesion. As mucus is accumulated and the sinus cavity has filled, the increase in intraantral pressure results in a thinning, displacement and, in some cases, destruction of the sinus walls. If the mucocele becomes infected, it is called a pyocele or a mucopyocele.
References
Oral Radiology: Principles and Interpretation. 5th edition. White and Pharaoah. p. 585.