Abstract:Objective To explore the efficacy of iRoot SP combined with oral repair membrane for covering bone defect area in the treatment of chronic apical periodontitis with periapical shadow.Methods The patients with chronic apical periodontitis (120 teeth) admitted to Tianjin Stomatological Hospital from January 2020 to December 2022 were selected. Based on different types of treatment, the affected teeth were divided into a control group and an observation group, with 60 cases in each group. The control group was treated with iRoot SP root canal sealer combined with root canal obturation by warm vertical condensation, while the observation group was additionally treated with oral repair membrane for covering bone defect area. All patients underwent postoperative X-ray examination. The severity of acute response (grade 0, grade Ⅰ, grade Ⅱ, and grade Ⅲ), effective rates 3 and 6 months after treatment, changes in periapical shadows, and pain conditions 1, 3, and 7 d after treatment recorded by follow-up and Visual Analogue Scale (VAS) were compared between the two groups. The concentration of leaked glucose was detected via colorimetric assays based on glucose oxidase in the microleakage detection device 1, 2, 4, 7, 14, 21, and 28 d after treatment, and thus evaluating the condition of apical microleakage. The rate of dental sealants overfilling was compared between the two groups.Results The observation group showed milder acute response within one week after root canal filling compared with the control group (P < 0.05). The effective rates of root canal filling 3 and 6 months after treatment in the observation group were higher than those in the control group (P < 0.05). No patients in the observation group experienced spontaneous pain or biting pain, and clinical examination did not show positive signs such as percussion pain and tenderness. The X-ray imaging of the control group exhibited that the periapical shadows of 29 affected teeth completely disappeared, 19 decreased, and 12 remained unchanged, with a total effective rate of 80.0%. In contrast, the X-ray imaging of the observation group demonstrated that the periapical shadows of 47 affected teeth completely disappeared, and 13 decreased, with a total effective rate of 100.0%. The VAS scores of the control group and the observation group 1, 3, and 7 d after surgery were compared, which showed that they were different among the time points (P < 0.05) and between groups (P < 0.05), and that the change trends of them were also different between groups (P < 0.05). In terms of the concentration of leaked glucose, the comparison between the control group and the observation group 1, 2, 4, 7, 14, 21, and 28 d after treatment suggested that the concentration of leaked glucose was different among the time points (P < 0.05) and between the groups (P < 0.05), and that the change trend of the concentration of leaked glucose was different between the two groups (P < 0.05). There was no difference in the rate of dental sealants overfilling between the control group and the observation group (P > 0.05).Conclusion The combination of iRoot SP and oral repair membrane for covering bone defect area can significantly improve the therapeutic efficacy for periapical shadows in chronic apical periodontitis by alleviating the pain and effectively reducing the apical microleakage.