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What is Passavant ridge ? and explain in detail?
Passavant ridge Near the superior margin of pharynx, a few fibres of superior constrictor blend with a band of muscle fibres belonging to the palatopharyngeus muscle. These fused fibres form a band or ring around the posterior wall and sidewalls of the nasopharyngeal isthumus. When the soft palate is elevated this muscle band appears as a ridge is known as passavant's ridge.