Labyrinthine aplasia, microtia, and microdontia are all congenital conditions that can cause deafness. Labyrinthine aplasia is caused by a malformation of the inner ear, which can lead to hearing loss. Microtia is a condition in which the external ear is underdeveloped, which can lead to hearing loss. Microdontia is a condition in which the teeth are abnormally small, which can lead to hearing loss due to the abnormal development of the middle ear bones. Other causes of deafness associated with these conditions include genetic mutations, environmental factors, and infections.