Eustachian tube dysfunction: This condition is a common cause of ear fullness sensation, especially in the absence of acute otitis media (AOM) and impacted cerumen. The Eustachian tube helps regulate air pressure in the ear, and dysfunction can lead to a feeling of fullness or blockage.

Middle ear effusion: Fluid accumulation in the middle ear can cause a sensation of fullness, even in the absence of AOM. This condition may be related to Eustachian tube dysfunction or other factors.
Patulous Eustachian tube: This condition, where the Eustachian tube remains open, can also lead to ear fullness, especially when lying down or during certain activities.
Nasopharyngeal carcinoma: Although less common, nasopharyngeal carcinoma can cause Eustachian tube obstruction, leading to ear fullness.

Acoustic neuroma: A benign tumor on the nerve connecting the inner ear to the brain, which can cause ear fullness, among other symptoms. Early detection is crucial for effective management.
Multiple sclerosis: This condition can affect the brain and spinal cord, leading to a variety of symptoms, including ear fullness. Although rare, it's essential to consider in the differential diagnosis.
Temporomandibular joint (TMJ) disorder: TMJ disorders can cause referred pain and fullness in the ear, making it a critical diagnosis not to miss.

Otosclerosis: A condition characterized by abnormal bone growth in the middle ear, which can cause ear fullness, hearing loss, and other symptoms.
Meniere's disease: A disorder of the inner ear that affects balance and hearing, causing symptoms like ear fullness, vertigo, and tinnitus.
Labyrinthitis: Inflammation of the inner ear, which can cause ear fullness, vertigo, and hearing loss.