pregabalin and Toothache

A 48-year old woman in good general health was referred to the orofacial pain clinic in a centre for special dentistry with a toothache in the premolar region of the left maxillary quadrant. The complaints had existed for 15 years and various dental treatments, including endodontic treatments, apical surgery, extraction and splint therapy, had not helped to alleviate the complaints. As a result of the fact that anti-epileptic drugs were able to reduce the pain it was concluded that this 'toothache' satisfied the criteria of an atypical odontalgia: 'toothache' with a neuropathic background.. Een 48-jarige vrouw in goede algemene gezondheid presenteerde zich op de afdeling Gnathologie van een centrum voor bijzondere tandheelkunde met pijnklachten in het tweede kwadrant. De klachten bestonden reeds 15 jaar en diverse tandheelkundige behandelingen, waaronder endodontische behandelingen, chirurgische apicale endodontische behandeling, extractie en de vervaardiging van een stabilisatieopbeetplaat, hadden niet geholpen. Uit het feit dat een anti-epilepticum de pijn deed afnemen, werd geconcludeerd dat er sprake was van atypische odontalgie: ‘kiespijn’ met een neuropathische achtergrond.

Topics: Analgesics; Chronic Pain; Diagnosis, Differential; Female; Humans; Middle Aged; Pregabalin; Toothache; Treatment Outcome; Trigeminal Neuralgia

Our previous studies have demonstrated that application of inflammatory irritant mustard oil (MO) to the tooth pulp induces medullary glutamate release and central sensitization in the rat medullary dorsal horn (MDH), as well as nociceptive sensorimotor responses in craniofacial muscles in rats. There is recent evidence that anticonvulsant drugs such as pregabalin that influence glutamatergic neurotransmission are effective in several pain states. The aim of this study was to examine whether systemic administration of pregabalin attenuated glutamate release in the medulla as well as these nociceptive effects reflected in increased electromyographic (EMG) activity induced by MO application to the tooth pulp. Male adult rats were anesthetized with isofluorane (1.0-1.2%), and jaw and tongue muscle EMG activities were recorded by needle electrodes inserted bilaterally into masseter and anterior digastric muscles and into the genioglossus muscle, and also the medullary release of glutamate was assessed by in vivo microdialysis. Pregabalin or vehicle control (isotonic saline) was administered 30 min before the pulpal application of MO or vehicle control (mineral oil). Application of mineral oil to the maxillary first molar tooth pulp produced no change in baseline EMG activity and glutamate release. However, application of MO to the pulp significantly increased both the medullary release of glutamate and EMG activity in the jaw and tongue muscles for several minutes. In contrast, pre-medication with pregabalin, but not vehicle control, significantly and dose-dependently attenuated the medullary glutamate release and EMG activity in these muscles after MO application to the tooth pulp (analysis of variance (ANOVA), p<0.05). These results suggest that pregabalin may attenuate the medullary release of glutamate and associated nociceptive sensorimotor responses in this acute inflammatory pulpal pain model, and that it may prove useful for the treatment of orofacial inflammatory pain states.

Topics: Analgesics; Animals; Dental Pulp; Disease Models, Animal; Electromyography; Facial Muscles; gamma-Aminobutyric Acid; Glutamic Acid; Inflammation; Irritants; Male; Medulla Oblongata; Microdialysis; Mustard Plant; Plant Oils; Pregabalin; Rats; Rats, Sprague-Dawley; Toothache