Gene expression analysis of neuropeptides in oral mucosa during periodontal disease in non-human primates.

BACKGROUND: Neuropeptides (NPs) are innate pivotal regulators of the immunoinflammatory response. Nevertheless, their role in the pathogenesis of periodontal disease remains unknown. Changes in gene expression of 10 NPs and 16 NP receptors (NPRs) coincident with the initiation, progression, and resolution of periodontitis were determined. METHODS: The ligature-induced periodontitis model was used in rhesus monkeys (n = 18). Gingival tissue samples were taken at baseline (preligatures), at 2 weeks and at 1 month (initiation), and at 3 months (progression) postligation. Ligatures were removed and samples taken 2 months later (resolution). Total RNA was isolated from tissues and NP/NPR gene expression microarray analysis was performed. Gene expression changes were validated by quantitative polymerase chain reaction and immunohistochemistry. RESULTS: Unexpectedly, the expression of pro-inflammatory NPs/NPRs did not change during periodontitis or with resolution. However, increased expression of the anti-inflammatory NPs adrenomedullin (ADM) and galanin (GAL), and the NPRs calcitonin receptor-like (CALCRL) and receptor activity-modifying protein-2 and -3 (RAMP2 and RAMP3) were observed during initiation and progression of disease. The expression of the same NPs/NPRs exhibited a significant positive correlation with both molecular (interleukin-1ß, matrix mettaloproteinase-9, and receptor activator of nuclear factor-kappa B ligand) and clinical measures of gingival inflammation and tissue destruction. CONCLUSION: Initiation and progression of periodontitis involve significant overexpression of ADM, GAL, CALCRL, RAMP2, and RAMP3. These anti-inflammatory NPs/NPRs could play a role in the unresolved infection and inflammation that normally drives tissue destruction in periodontitis. Both ADM and GAL potentially are new candidates to consider as biomolecules associated with periodontal disease activity.

Resolution of Implant-Induced Neurosensory Disturbance: A Procedural Failure.

PURPOSE: This case report describes the improvement of a patient's neurosensory symptoms after the removal of a mandibular implant within 24 hours of initial placement. After 1 year, neurosensory symptoms resolved, and a different sized dental implant was successfully placed at the same surgical site. MATERIALS AND METHODS: A 45-year-old woman experienced neurosensory disturbance along the inferior alveolar mandibular nerve after a dental implant surgery. A panoramic radiograph, obtained within 24 hours of implant placement, suggested a possible case of implant intrusion into the inferior alveolar nerve canal. After thorough evaluation, the implant was removed within 24 hours of initial placement, and the patient was followed up for 1 year. The neurosensory functions of the patient's chin and lower lip regions were assessed before implant removal, and 1 month and 1 year after the removal of the implant. RESULTS: Almost complete resolution of altered sensation occurred 1 year after implant removal. A second, shorter implant was placed at the same site with no subsequent symptoms of impaired sensation. CONCLUSION: This report highlights the plausible placement of a different size dental implant in the same area of previous-implant-induced nerve injury. The authors report that a lack of postoperative radiograph by the surgeon was considered to be a procedural failure.