Association between Bruxism and Cervical Spine Position in Human Subjects: A Systematic Review and Meta-analysis of Observational Studies.

Abstract

<h4>Background</h4>Bruxism is a parafunctional habit affecting the stomatognathic system, with possible detrimental effects on the cervical spine position and, consequently, the head posture.<h4>Objectives</h4>The present study aimed at assessing the association between bruxism and cervical spine position in human subjects.<h4>Search methods</h4>Two researchers, SHS and LNM, independently searched articles using appropriate keyword combinations in four search engines: PubMed, Cochrane Library, Semantic Scholar, and Google Scholar. Conflicts, if any, were resolved by AMJ. Studies either reported in English or with complete translations available in English were selected.<h4>Selection criteria</h4>Observational studies reporting bruxism and cervical position from cephalometric to photographic parameters were considered. Interventional studies were included only to collect the baseline observational data.<h4>Data collection and analysis</h4>From 22 studies, a total of nine studies were included in the systematic review and five in the meta-analysis (three with cephalometric and two with photographic parameters). 1. CVT-HOR Angle between tangent (CVT) to the cervical vertebra (CV4) and horizontal line (HOR); 2. OPT-HOR Angle between the tangent (OPT) to odontoides (CV2) and horizontal line (HOR); 3. CVT-VV Angle between tangent (CVT) to the cervical vertebra (CV4) and vertical line (VV); 4. OPT-VV Angle between the tangent (OPT) to odontoides (CV2) and vertical line (VV) (cephalometric), and craniocervical angle (photographic) were considered as dependent variables for the analyses; bruxism being the independent variable.<h4>Results</h4>Three studies (120 subjects) showed changes in the cephalometric parameters, and two studies (45 subjects) showed changes in the photographic parameters. Using Fixed Effect Model (FEM), standardized mean difference [SMD (95% CI)] for variables CVT-HOR [-0.62 (-0.99, -0.24)], OPT-HOR [-0.67 (-1.04, -0.29)], and OPT-VV [0.76 (0.38, 1.14)] were all statistically significant with low heterogeneity (<i>I</i>² = 25, 0, 0). The Risk of Bias (ROB) across studies assessed using the AXIS tool was low. These parameters show a statistically significant difference in head posture between individuals with bruxism and without bruxism, relating to anterior positioning of the cervical spine in individuals with bruxism.<h4>Conclusion</h4>Association exists between bruxism and cervical spine position in human subjects with respect to the aforementioned variables of interest.<h4>Prospero registration</h4>CRD42023433635.<h4>How to cite this article</h4>Solanke SH, Mistry LN, Jawdekar AM. Association between Bruxism and Cervical Spine Position in Human Subjects: A Systematic Review and Meta-analysis of Observational Studies. Int J Clin Pediatr Dent 2025;18(8):1039-1045.