Correlation Between Orofacial Pain and Sensory and Autonomic Neuropathies.

Purpose: Orofacial Pain (OFP) affects 15% of the general population. OFP conditions can be myofascial, also known as temporomandibular disorders (TMDs) or neuropathic. The underlying pathophysiology in several chronic OFP conditions, is unknown. Small fiber neuropathy (SFN) is a disorder of thinly myelinated A-delta and non-myelinated C-fibers and can manifest as sensory and autonomic neuropathies. SFN has been demonstrated in some OFP conditions. Our study aims to assess the presence of OFP in patients with sensory and autonomic neuropathies and assess the correlation between OFP, skin biopsy and autonomic dysfunction. Patients and Methods: This is a retrospective study (2018-2020) of patients from the SFN registry, Massachusetts General Hospital, Boston, USA, for the presence of OFP. All patients were included. Primary outcome: Prevalence of OFP in patients with chronic neuropathies. Secondary outcomes: Correlation between OFP and skin biopsy, dysautonomia, headaches, chronic nociceptive pain, psychological conditions, and patient factors, such as mean age and BMI. Results: Charts of 450 patients with sensory and autonomic neuropathies were reviewed. 22.67% (n=102) had OFP. The mean (range) age at biopsy in patients with OFP was 48.36 (20-81) years, female: male ratio 3.25:1. More OFP patients had negative skin biopsy results (p value<0.05) than those with sensory neuropathies. Patients with OFP had significantly higher prevalence of psychological conditions (p value 0.000), and higher BMI >30 (p value 0.025). Dysautonomia was significantly higher in patients with TMDs when compared to the ones without TMDs (p value 0.030). There was no significant difference in mean age, gender predilection, presence of headaches, peripheral neuropathies, and nociceptive pain between patients with and without OFP. Conclusion: OFP and sensory neuropathies can be overlapping conditions. Patients presenting with concomitant TMD and dysautonomia can be further tested for SFN. This can further help us understand a correlation if any, between idiopathic TMD/OFP conditions and SFN and further our understanding of the pathophysiology of these conditions.

Elevated Cytokine Levels in Gingival Crevicular Fluid of Teeth with Apical Periodontitis.

INTRODUCTION: Biomarkers assayed from gingival crevicular fluid (GCF) are a potential tool for endodontic diagnosis and for monitoring treatment response. This cross-sectional study measured cytokines in GCF from teeth with apical periodontitis and evaluated their relationship with preoperative pain and other clinical findings. METHODS: Participants presenting for root-end resection surgery due to apical periodontitis diagnosis (n = 56) underwent standardized clinical testing and completed preoperative questionnaires. GCF from diseased and control teeth were collected, processed, and analyzed. Mann-Whitney U and Wilcoxon tests were used to examine the cytokine levels in diseased compared to healthy control teeth. We also assessed the relationship of cytokine levels with clinical findings. RESULTS: Interleukins (IL)-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, interferon-γ, and tumor necrosis factor-⍺ (TNF-⍺) were detected in GCF. TNF-⍺ levels were significantly higher in GCF collected from diseased versus control teeth (P = .02) and increased IL-1ß levels in diseased teeth were detected (P = .06). Lower IL-10 levels were observed in teeth with a sinus tract and/or swelling compared to teeth without a sinus tract and/or swelling (P = .08). Cytokine levels did not clearly relate to the presence of pain. CONCLUSIONS: Elevated levels of proinflammatory cytokines, including TNF-⍺ and IL1- ß, were detected in GCF from diseased teeth compared to the healthy controls. Additional studies are needed to further investigate the utility of these biomarkers for objectively evaluating periradicular pathology.