Study Of The Factors Influencing The Occurrence Of Pain In Temporomandibular Disorders And The Establishment Of A Predictive Model

Background: Chronic pain significantly threatens human health;temporomandibular disorder(TMD)is the most common orofacial pain disorder.After non-invasive treatment,some TMD patients still experience persistent pain that develops into chronic pain,causing significant physical and psychological distress.These patients return for repeat treatment,resulting in high medical and socioeconomic costs.Previous studies have shown that,in addition to treatment methods,essential risk factors still influence the prognosis of the disease.It is of social and economic importance to explore the risk factors that influence chronic pain and to develop a risk prediction model based on these factors.However,little is known about the risk factors influencing TMD pain and chronic pain,and there are no reliable risk prediction models.Based on this,in order to provide a screening tool for the early management of chronic pain,this study was based on analyzing factors influencing TMD pain to identify independent risk factors for the development of chronic TMD pain and to establish and validate a risk prediction model for chronic painful TMD after non-invasive treatment.The study is divided into two parts:Study 1: Analysis of the factors influencing TMD painObjective: To identify the risk factors associated with pain affecting TMD.Methods: This cross-sectional study included 488 TMD patients who first visited the Ninth People’ s Hospital between December 2020 and August 2021.The subjects’ pain was assessed using the Numerical Rating Scale(NRS).The sociodemographic,behavioral,psychological,and disease-related data were collected through clinical examination,face-to-face interviews,and questionnaires.Multiple linear regression analysis was used to analyze the direct influences on TMD pain.The mediation effect analysis was used to examine the interaction of oral behaviors with psychological factors and sleep quality and their indirect effects on pain.Results:(1)Marital status(β=0.094,P=0.008),diagnosis subgroup(β=0.573,P<0.001),previous medication use(β=0.573,P<0.001),depression(β=0.573,P=0.029)and sleep quality(β=0.056,P=0.041)could significantly predict the pain scores.(2)Although there was no direct effect of oral behaviors on TMD pain(95% confidence interval(CI),-0.306,0.093),these behaviors influenced pain through their effects on depression(effect,0.073;95% CI,0.025,0.142)and sleep quality(effect,0.065;95%CI,0.013,0.139).Conclusion: TMD pain are consistent with the bio-psycho-social model.Marital status,diagnosis subgroup,previous medication use,depression,and sleep quality were significant factors affecting TMD pain.Oral behaviors,although not directly influencing TMD pain,could influence pain by modulating depression and sleep quality.Study 2: Establishment and validation of a risk predictive model of chronic painful TMD after non-invasive treatmentObjective:(1)To identify the independent risk factors of chronic TMD pain;(2)To establish and validate the risk prediction model of chronic painful TMD after non-invasive treatment.Methods: This prospective study included 488 subjects who participated in study 1.All the subjects received non-invasive treatment,and their prognosis was obtained through telephone follow-up 12 months after the baseline.Based on the sociodemographic,behavioral,psychological,and disease-related data collected in study 1,we screened for risk factors associated with TMD pain as the independent variable.The occurrence of chronic pain as the dependent variable.Single-factor and multi-factor Logistic regression analyses were used to screen predictors and establish the risk prediction model.A nomogram was used to visualize the model.The discrimination,calibration,and clinical practicability were evaluated by the Area under curve(AUC),C-index,Calibration plot,and Decision Curve Analysis(DCA).The Bootstrap method was used to validate the model internally and repeatedly tested the C-index.Results:(1)Independent risk factors associated with chronic TMD-related pain after non-invasive treatment include somatization,anxiety,sleep quality,and baseline pain intensity.(2)The above significant predictors were included,and the nomogram risk prediction model was successfully constructed.The model has good discrimination(AUC=0.829,C-index=0.858),calibration(the calibration curve fits well with the ideal situation),and clinical practicability(when the threshold probability is in the range of 10%～98%,the model is clinically useful).Similar C-indexes were obtained before and after internal validation(0.858,0.843)and good predictive performance(C-index=0.843).Conclusion: The independent risk factors of chronic pain in TMD patients is somatization,anxiety,sleep quality,and baseline pain intensity.A nomograph risk prediction model was established based on the above independent risk factors,which have good discrimination,calibration,and clinical practicability and passed internal validation,providing a reliable quantitative tool for risk prediction of TMD chronic pain.