Brain activation in cold induced toothache:Evidence from functional magnetic resonance imaging(fMRI) / 实用口腔医学杂志

ABSTRACT

Objective:To evaluate the feasibility of fMRI on the location of brain regions related to cold stimulated toothache. Methods: 8 patients with cold induced dentinalgia of the right maxillary bicuspid and 8 healthy volunteers with full and healthy dentition were selected to perform the fMRI study, all of which are right handed. Block designed blood oxygen level dependent(BOLD) functional MRI scan covering the whole brain was carried out. SPM2 software was adopted to generate the activation map. Results: The patient group showed significant bilateral activations in insula/SII, basal ganglion, cingulate gyrus, midbrain red nucleus. BOLD signals were also found unilaterally in right thalamus, inferior parietal lobule(BA7) and left inferior frontal gyrus(BA44), MII/PMC. In contrast, the normal group showed increased signals in bilateral PMC and inferior parietal lobule BA40. Left lentiform nucleus, SI/MI and right inferior parietal lobule(BA7) were also excited in none painful cold sensation. Conclusions: Motor related cortex including PMC, SMA and BA44 have strong signals during dental pain. Compared with limb pain, tooth pulp stimulation evoked a more pronounced activation in the ipsilateral hemisphere in some brain regions.