Table 1.

Three most popular theories of trigeminal neuralgia aetiology

Diseases related	Direct injury to the trigeminal nerve		Polyetiologic origin
	Peripheral part of TNS	Central part of TNS
Vascular diseases, multiple sclerosis, diabetes mellitus, rheumatism and others.	"Allergic hypothesis" due to odontogenic inflammatory diseases, otolaryngological pathology, getting cold and others.	"Neurovascular compression hypothesis" at the root entry zone due to arteriovenous malformation, vestibular schwannomas, meningiomas, epidermoid cysts, tuberculomas, various other cysts and tumours, aneurysm, vessels aggregation and occlusion due to arachnoiditis and others.	All possible aetiological factors that can affect TNS and evoke demyelination and dystrophy.
	"Compression syndrome hypothesis" due to the narrowing of the osseous canals, trauma.

TNS = trigeminal nerve system.