Objective:To use cone-beam computed tomography(CBCT)to conduct microscopic root canal therapy of micro-calcification and to analyze the influencing and prognostic factors of occurring endodontic inter appointment emergencies(EIAE)during root canal treatment.Methods:A total of 80 patients with root canal calcification who admitted to Suzhou Stomatological Hospital from February 2020 to February 2023 were selected,all of whom underwent CBCT examination and microscopic root canal therapy of micro-calcification.Based on the results of CBCT examination,the incidence of EIAE during root canal treatment and the prognosis post one year(missed filling,under filling,displacement of root canal)were analyzed by using statistical method.Multiple logistic regression analysis was used to analyze the influencing factors of occurring EIAE.Results:80 patients had a total of 100 calcified root canals,and the EIAEs incidence was 8.75%.The results of logistic regression analysis showed that gender,pre-treatment pain,pre-treatment fistula,apical shadow and vitality of dental pulp were all factors affecting the occurrence of EIAEs(OR=2.217,1.249,1.405,1.320,1.835,P＜0.05),respectively.The vitality of dental pulp,pre-treatment fistula,preoperative presence or absence of apical shadow,filling length of root canal,filling density and crown leakage were all factors affecting the prognosis of micro root canal treatment(OR=1.256,1.425,1.237,1.225,1.280,1.267,P＜0.05),respectively.Conclusion:In the microscopic root canal therapy,CBCT imaging can have a more detailed understanding of the morphology of calcified root canal and can clarify the direction of the root canal,which can help the individual characteristics of the affected teeth,and can contribute to formulate treatment plans,and strengthen the evaluation and analysis of prognosis,and improve the treatment effect.

Objective:To investigate the clinical application value of photodynamic therapy(PDT)mediated by diode laser,which combined with disinfection in root canal in patients with combined periodontal-endodontic lesions.Methods:A total of 100 patients with combined periodontal-endodontic lesions who admitted to the Suzhou Stomatological Hospital from November 2021 to December 2023 were selected,and they were randomly divided into the observation group and control group,with 50 cases in each group.The control group underwent disinfection treatment in root canal,and the observation group underwent PDT treatment based on the treatment of control group.The clinical efficacy,the bacteria count in root canal,the expression levels of inflammatory factors of gingival crevicular fluid,which included interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ),as well as periodontal related indexes such as periodontal pocket depth(PD),gingival sulcus bleeding index(SBI)and periodontal attachment loss(AL),were compared between the two groups.Results:After treatment,the effect of 28 cases(56%)was significant,and that of 20 cases(40%)was effective,and 2 cases(4%)were ineffective,and the total effective rate was 96.00%in the observation group.The effect of 20 cases(40%)was significant,and that of 21 cases(42%)was effective,and 9 cases(18%)were ineffective,and the total effective rate was 82.00%in the control group.The total effective rate of the observation group was significantly higher that of the control group,with a statistically significant difference(x2=4.639,P＜0.05).Compared with the control group,the bacteria count in root canal of observation group significantly decreased,and the IL-6 and TNF-α of observation group significantly decreased,and the differences were significant(t=6.524,5.268,4.394,P<0.05).There was no significant difference in IFN-γ levels between the two groups(P＞0.05).After treatment,the PD,SBI and AL indicators in both groups significantly reduced,and the above indicators of observation group were more lower than these of control group,and the differences were significant(t=5.401,6.309,7.006,P＜0.001),respectively.Conclusion:PDT combined with disinfection in root canal can significantly improve clinical efficacy in treating combined periodontal-endodontic lesions,and can reduce bacterial count in root canal and the levels of inflammatory factors of gingival crevicular fluid,and improve the indicators of periodontal health.