Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Jul;60(7):1021-9.
doi: 10.1016/j.archoralbio.2015.03.006. Epub 2015 Mar 28.

GABA and glutamate levels in occlusal splint-wearing males with possible bruxism

Shalmali Dharmadhikari  1 , Laura M Romito  2 , Mario Dzemidzic  3 , Ulrike Dydak  4 , Jun Xu  5 , Cynthia L Bodkin  6 , Shalini Manchanda  7 , Kenneth E Byrd  8
Affiliations

GABA and glutamate levels in occlusal splint-wearing males with possible bruxism

Shalmali Dharmadhikari et al. Arch Oral Biol. 2015 Jul.

Abstract

Objective: The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in the pathophysiology of anxiety behavioural disorders such as panic disorder and post-traumatic stress disorder and is also implicated in the manifestation of tooth-grinding and clenching behaviours generally known as bruxism. In order to test whether the stress-related behaviours of tooth-grinding and clenching share similar underlying mechanisms involving GABA and other metabolites as do anxiety-related behavioural disorders, we performed a Magnetic Resonance Spectroscopy (MRS) study for accurate, in vivo metabolite quantification in anxiety-related brain regions.

Design: MRS was performed in the right hippocampus and right thalamus involved in the hypothalamic-pituitary-adrenal axis system, together with a motor planning region (dorsal anterior cingulate cortex/pre-supplementary motor area) and right dorsolateral prefrontal cortex (DLPFC). Eight occlusal splint-wearing men (OCS) with possible tooth-grinding and clenching behaviours and nine male controls (CON) with no such behaviour were studied.

Results: Repeated-measures ANOVA showed significant Group×Region interaction for GABA+ (p = 0.001) and glutamate (Glu) (p = 0.031). Between-group post hoc ANOVA showed significantly lower levels of GABA+ (p = 0.003) and higher levels of Glu (p = 0.002) in DLPFC of OCS subjects. These GABA+ and Glu group differences remained significant (GABA+, p = 0.049; Glu, p = 0.039) after the inclusion of anxiety as a covariate. Additionally, GABA and Glu levels in the DLPFC of all subjects were negatively related (Pearson's r = -0.75, p = 0.003).

Conclusions: These findings indicate that the oral behaviours of tooth-grinding and clenching, generally known as bruxism, may be associated with disturbances in brain GABAergic and glutamatergic systems.

Keywords: Anxiety; Bruxism; GABA; MRS; Metabolites; Pathophysiology.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Sagittal and axial views showing representative VOI placement in the thalamus, hippocampus, DLPFC and dACC/preSMA (left column) and the respective short TE single voxel 1H PRESS spectra (middle column) and MEGA-PRESS GABA spectra (right column). The GABA+ peak at 3 ppm is very prominent for all four regions of interest. VOI = Volume Of Interest.
Figure 2
Figure 2
In the DLPFC, a significant negative correlation (Pearson coefficient=−0.754, p=0.003) is present between GABA+ and Glu concentrations.
Figure 3
Figure 3
In the hippocampus, a significant positive correlation (Pearson coefficient=0.783, p=0.004) is present between GABA+ and Glu concentrations.
See this image and copyright information in PMC

References

    1. Lobbezoo F, Ahlberg J, Glaros AG, Kato T, Koyano K, Lavigne GJ, et al. Bruxism defined and graded: an international consensus. J Oral Rehabil. 2013;40(1):2–4. - PubMed
    1. Medicine AAoS . International classification of sleep disorders, 2nd ed: diagnostic and coding manual. American Academy of Sleep Medicine; Westchester, IL: 2005. pp. 51–55.
    1. Laberge L, Tremblay RE, Vitaro F, Montplaisir J. Development of parasomnias from childhood to early adolescence. Pediatrics. 2000;106(1 Pt 1):67–74. - PubMed
    1. Ohayon MM, Li KK, Guilleminault C. Risk factors for sleep bruxism in the general population. Chest. 2001;119(1):53–61. - PubMed
    1. Lavigne GJ, Montplaisir JY. Restless legs syndrome and sleep bruxism: prevalence and association among Canadians. Sleep. 1994;17(8):739–743. - PubMed

Publication types