Pretrigeminal neuralgia

Abstract

Typical trigeminal neuralgia, brief electric shock like pain along distribution of trigeminal nerve, is well documented in literature but not much is available about pre trigeminal neuralgia. Pre-trigeminal neuralgia should be considered in the differential diagnosis of pain of dental origin because of its similar features.Symonds was the first person who noted dull, continuous and aching pain before the typical paroxysmal pain appeared in few patients. [1] Mitchell was the person to term this prodromal pain as " pre-trigeminal neuralgia. Clinical features of this prodromal pain includesdull, continuous aching pain that may be triggered or aggravated by chewing food, drinking hot and cold liquids. Such patients pose a diagnostic challenge for dentist as examination may reveal absence of caries, gingival recession, sinusitis and symptoms are not relieved with analgesics like NSAIDs and opioids. Root canal treatment and extraction are also of no use in such patients because painpersists in the same region even after performing root canal treatment or extraction. So a careful history and detailed dental and neurological examination is required in such patients to avoid misdiagnosis as dental disease. Differential diagnosis of pre trigeminal neuralgia includes dental pain of pulpal origin, sinusitis, myofacial pain dysfunction syndrome (MPDS), atypical facial pain, TMJ disorders and trigeminal neuralgia. Pain of pulpal origin can be differentiated with careful dental examination and intra oral radiographs. Presence of blocked nose, purulent nasal discharge, tenderness over cheek areas and paranasal sinus (PNS view) radiograph can help in diagnosis ofsimilar pain in maxillary premolar or molar region due to maxillary sinusitis. TMJ disorders and MPDS presents with chronic orofacial pain that aggravates with movement of jaws. Tenderness of muscles of mastication, clicking sound in TMJ and limited mouth opening are characteristic features of MPDS. Atypical facial pain is associated with psychogenic causesin which patient complains of poorly localized throbbing pain or burning sensation in apparently normal teeth or jaws that responds poorly to all treatment plans except antidepressants. Clinical presentation with brief electric shock like pain along the course of nerve, presence of triggering zones and triggering factors helps in differentiating typical trigeminal neuralgia from pre-trigeminal neuralgia. Therapeutic diagnosis is the method to diagnose such cases by giving small doses of carbamazepine and baclofen for few days. A dosage of 100mg of carbamazepinethrice dailywas found sufficient forrelief of symptoms and to confirm the diagnosis.5 Although incidence of such cases is very low but dentist should be …