591 INTRODUCTION Primary and referred pain patterns depend on the intensity, localization and timing of the perceived pain stimulus which can produce neuropathic pain (Sessle et al., 1986). It can also simulate pathologies’ apparently unconnected symptomatic behavior. Neuropathic pain pathophysiology and etiology are neither clear nor defined as yet. Peripheral neuropathic pain originates in the pathological change of nociceptive afferent nervous fibers caused by injured tissue being produced during the microtrauma or macrotrauma creating inappropriate peripheral or central pain signals (Moskowitz, 1984). Neuropathic and neurogenic pain can be expressed having vegetative implications, among other neurovascular manifestations (Ertsey et al., 2004). Autonomic nervous system (ANS) involvement in producing pain is an ongoing debatable matter. The pain influences and is influenced by the ANS. Trigeminal autonomic cephalalgias (TAC) and Complex Regional Pain Syndrome are presentations of pain having vegetative symptoms expressed as cranial autonomic symptoms which can be associated or disassociated with pain ( Bouhassira et al., 1994; Goadsby et al., 2001; Melis et al., 2002; Martins et al., 2004; Putzki et al., 2004). Such headache pain may be accompanied by considerable autonomic reactions in the head depending on parasympathetic and secondary sympathetic dysfunction (Hardebo, 1984; Goadsby & Edvinsson, 1993; Jänig, 2003; Gottselig & Messlinger, 2004). TAC consists of three separate presentations: cluster headache, paroxysmal hemicrania and SUNCT (short-lasting unilateral neuralgiform headache with conjunctival injection and tearing). Although cluster headache is known to be a primary headache disorder, various clinical reports have stated that it is a secondary presentation from multiple origins (Tfelt-Hansen et al., 1982; Sacquegna et al., 1982; Kudrow et al., 1984, Romoli & Cudia, 1988; Appelbaum & Noronha, 1989; Gawel et al., 1989; Hannerz, 1989; Formisano et al., Int. J. Morphol., 25(3):591-596, 2007. Trigeminal Autonomic Cephalalgia by Neurogenic Palatine Compression: A Clinical Report and Review Cefalea Autonómica Trigeminal por Compresión Neurogénica Palatina: Reporte de Caso y Revisión * Ramirez Luis Miguel; ** Ballesteros Luis Ernesto & *** Sandoval Germán Pablo RAMIREZ, L. M.; BALLESTEROS, L. E. & SANDOVAL, G. P. Trigeminal autonomic cephalalgia by neurogenic palatine compression: A clinical report and review. Int. J. Morphol., 25(3):591-596, 2007. SUMMARY: This clinical report presents the evolution of a possible intraoral traumatic trigeminal autonomic cephalalgia simulating a probable cluster headache. A 50-year-old female patient had severe right-hand side pain for 7 years with autonomic signs and symptoms, such as lacrimation, conjunctival injection, rhinorrhoea, nasal congestion, forehead perspiration, myosis and eyelid edema. The episodes of pain lasted 4 or 5 months with 3- or 4-month remission periods between the painful onsets. The headaches presented an episodic pattern (1 to 3 attacks daily) lasting three to six hours. The patient had used five prosthetic sets continuously (24 h) for 20 years and the current prosthesis was 7 years old. Accidentally, after the alleviation of the maxillary denture due to it rested on a marked irritated incisive papilla the symptoms disappear. The patient has been periodically checked over a 5 year period since, without recurrence of her pain and autonomic symptomatology. The possible pathophysiology is discussed. KEY WORDS: Sphenopalatine Ganglion; Incisive Papilla; Neurovascular Pain; Referred Pain; Temporomandibular Disorders. * Odontology - Prosthetic Dentistry and Temporomandibular Disorders. Medical Education in Orofacial-Otic referred symptoms. Associate Professor of Morphology - Department of Basic Sciences - Medicine Faculty - Universidad Industrial de Santander - Bucaramanga - Colombia. ** Medical Doctor with Degree in Anatomy. Basic Sciences Department Director. Professor of Morphology - Department of Basic Sciences - Medicine Faculty - Universidad Industrial de Santander. Bucaramanga - Colombia. *** Otolaryngology. Surgery Professor - Medicine Faculty - Universidad Industrial de Santander. Bucaramanga - Colombia.