Establishing the Role of Neurogenic Inflammation in the Pathogenesis of Periodontitis: A Systematic Review.

The role of neurogenic inflammation in various systemic diseases has been well established, but there is a dearth of studies and evidence regarding its role in periodontitis. This study aimed to systematically review the evidence in establishing the role of neurogenic inflammation in chronic periodontitis. Databases such as PubMed, Scopus, and Google Scholar were reviewed. We analyzed studies of any design that compared and evaluated the presence of neuropeptides such as substance P, calcitonin gene-related peptide, neurokinin A, neuropeptide Y, and vasoactive intestinal polypeptide in systemically healthy patients with and without periodontitis. We screened 2,495 articles and abstracts electronically and manually, which yielded 191 articles relevant to our study. Full-text examination of these 191 articles led to the final inclusion of 14 publications. Most studies here confirmed an association between various neuropeptides and periodontitis, but there is a high heterogeneity between the studies, making it necessary to clarify the mechanism between these two. Although most studies included in this review found a positive association between neurogenic inflammation and periodontitis, the evidence is of moderate to low quality.