To see bruxism: a functional MRI study

Abstract

Objective: Since the pathophysiology of bruxism is not clearly understood, there exists no possible treatment. The aim of this study is to investigate the cerebral activation differences between healthy subjects and patients with bruxism on behalf of possible aetiological factors. Methods: 12 healthy subjects and 12 patients with bruxism, a total of 24 right-handed female subjects (aged 20-27 years) were examined using functional MRI during tooth-clenching and resting tasks. Imaging was performed with 3.0-T MRI scanner with a 32-channel head coil. Differences in regional brain activity between patients with bruxism and healthy subjects (control group) were observed with BrainVoyager QX 2.8 (Brain Innovation, Maastricht, Netherlands) statistical data analysis program. Activation maps were created using the general linear model: single study and multistudy multisubject for statistical group analysis. This protocol was approved by the ethics committee of medical faculty of Kirikkale University, Turkey (02/04), based on the guidelines set forth in the Declaration of Helsinki. Results: The group analysis revealed a statistically significant increase in blood oxygenation level-dependent signal of three clusters in the control group (p , 0.005), which may indicate brain regions related with somatognosis, repetitive passive motion, proprioception and tactile perception. These areas coincide with Brodmann areas 7, 31, 39 and 40. It is conceivable that there are differences between healthy subjects and patients with bruxism. Conclusions: Our findings indicate that there was a decrease of cortical activation pattern in patients with bruxism in clenching tasks. This indicates decreased blood flow and activation in regional neuronal activity. Bruxism, as an oral motor disorder concerns dentistry, neurology and psychiatry. These results might improve the understanding and physiological handling of sleep bruxism.

Cerebral Representation of Splint Therapy in Bruxism Patients; An fMRI Experiment

“…In order to equalize the number of individuals from both groups, data analysis was continued over 12 persons for each group. masticatory muscles is generated from the central nervous system and is supported by the fact that we observed cortical changes between healthy individuals and bruxism patients in clenching function in our preliminary experiment (16). Finding reduced mean percent signal changes in related cortical areas of bruxism patients relative to the same areas of control subjects supported this hypothesis.…”

“…These areas are associated with motor control of the biting force and mediate somatosensory feedback with which tactile proprioception is transferred (23,24). Yılmaz found a similar decreased activation pattern in bruxism patients compared to the control group (16). Additionally, it is reported that these areas play a role in motor attention (25).…”

Orthodontic tooth separation activates the hypothalamic area in the human brain

“…Recently, functional magnetic resonance imaging (fMRI) was introduced as an effective tool for non-invasively identifying the anatomical brain areas that are activated by afferent signals. 8 – 9 …”

A case report of brain activity during mastication

“…Hirano 등 8,9) 은 저작이 여러 인지 구에 많이 활용되고 있다 12,13) . 구강보건분야에서는 이갈이(bruxism) 와 이악물기(clenching) 시 뇌의 활성부위를 fMRI를 사용하여 확인한 바 있으나 자연스러운 저작 과정 중 뇌 활성을 확인한 연구는 거의 없 다 14,15) . 이에 이 연구를 통해 건강한 대상자의 자연스러운 저작 과정 에서 활성화되는 뇌영역에 대한 기초자료를 확립하고, 저작에 의한 뇌 신경 활성 분석 시 fMRI의 활용성을 검토하고자 한다.…”