Functional Imaging Unit, Center of Diagnostic Radiology and Neuroradiology, University of Greifswald, Germany.
Hum Brain Mapp. 2012 Dec;33(12):2984-93. doi: 10.1002/hbm.21466. Epub 2011 Nov 18.
Occlusal splints are a common and effective therapy for temporomandibular joint disorder. Latest hypotheses on the impact of occlusal splints suggest an altered cerebral control on the occlusion movements after using a splint. However, the impact of using a splint during chewing on its cerebral representation is quite unknown. We used functional magnetic resonance imaging (fMRI) to investigate brain activities during occlusal function in centric occlusion on natural teeth or on occlusal splints in fifteen healthy subjects. Comparisons between conditions revealed an increased activation for the bilateral occlusion without a splint in bilateral primary and secondary sensorimotor areas, the putamen, inferior parietal and prefrontal cortex (left dorsal and bilateral orbital) and anterior insular. In contrast, using a splint increased activation in the bilateral prefrontal lobe (bilateral BA 10), bilateral temporo-parietal (BA 39), occipital and cerebellar hemispheres. An additionally applied individually based evaluation of representation sites in regions of interest demonstrated that the somatotopic representation for both conditions in the pre- and postcentral gyri did not significantly differ. Furthermore, this analysis confirmed the decreasing effect of the splint on bilateral primary and secondary motor and somatosensory cortical activation. In contrast to the decreasing effect on sensorimotor areas, an increased level of activity in the fronto-parieto-occipital and cerebellar network might be associated with the therapeutic effect of occlusal splints.
咬合板是治疗颞下颌关节紊乱的常用且有效的疗法。关于咬合板影响的最新假说表明，使用咬合板后，对咬合运动的大脑控制会发生改变。然而，使用咬合板进行咀嚼对其大脑表现的影响尚不清楚。我们使用功能磁共振成像（fMRI）研究了十五名健康受试者在自然牙或咬合板上进行正中咬合时的咬合功能的大脑活动。条件之间的比较显示，在双侧初级和次级感觉运动区、壳核、下顶叶和前额叶皮层（左侧背侧和双侧眶额）以及前岛叶中，双侧无咬合板的咬合功能的激活增加。相比之下，使用咬合板会增加双侧前额叶（双侧 BA10）、双侧颞顶叶（BA39）、枕叶和小脑半球的激活。此外，基于个体的代表区域的评价表明，在中央后回和中央前回的两种条件的躯体定位代表没有显著差异。此外，该分析证实了咬合板对双侧初级和次级运动及感觉皮质激活的抑制作用。与对感觉运动区的抑制作用相反，额顶枕叶和小脑网络的活动水平增加可能与咬合板的治疗效果有关。
