Quantitative analysis and expression of salivary opiorphin in painful oral soft-tissue conditions: A descriptive study

Objectives: Opiorphin is an enkephalinase inhibitor which suppresses pain by acting on the opioid system. The levels of opiorphin in plasma and saliva have shown to vary in patients with burning mouth syndrome. This descriptive study was designed to estimate the salivary levels of opiorphin among individuals with painful oral soft-tissue conditions. Materials and Methods: Unstimulated whole saliva was collected from 60 individuals (20 controls, 20 traumatic and inflammatory conditions, and 20 patients with oral potentially malignant disorders [OPMDs] and oral cancer). The salivary levels of opiorphin were assessed through competitive enzyme-linked immunosorbent assay. Results: The mean level of opiorphin among controls was 7.108 ± 2.535 ng/ml, among individuals with traumatic and inflammatory conditions was 9.409 ± 2.369 ng/ml, and in individuals with OPMDs and oral cancer was 8.268 ± 2.414 ng/ml. A positive correlation was observed between salivary opiorphin levels and age of the patient (r = 0.028). Conclusion: The varying levels of opiorphin in painful oral mucosal conditions and with age indicate its role in local pain modulating mechanisms.