Changes in periapical radiograph signs before and after root canal treatment for chronic periapical periodontitis

Abstract Introduction This study aimed to observe the changes in periapical radiograph signs before and after root canal-based management chronic periapical periodontitis and their relationships with treatment prognosis. Materials and Methods One hundred patients (100 teeth) with chronic periapical periodontitis receiving root canal therapy were enrolled. Periapical radiograph signs before and after treatment were assessed. On the basis of the healing status of the periapical lesions at 12 months, patients were allocated into a healed group ( n = 74) and an unhealed group ( n = 26). The maximum horizontal diameter ( X ) and maximum vertical diameter ( Y ) of periapical shadows, as well as the maximum horizontal length ( L ) and maximum vertical height ( H ) of alveolar bone resorption were recorded. Potential risk and protective factors for nonhealing were analyzed. Results The values of X , Y , L , and H decreased progressively at 3, 6, and 12 months following treatment, and all were significantly smaller than before treatment ( p 2 mm and overfilling, coronal microleakage, instrument fracture, and increases in X , Y , L , and H at 3 months after treatment became risk factors for nonhealing at 12 months after root canal treatment, while retreatment after surgery was a protective factor ( p < 0.05). X , Y , L , and H at 3 months after treatment were positively correlated with the nonhealing risk of tooth apexes ( p < 0.05). Conclusions Periapical radiograph indicators were reduced after root canal treatment, which are closely related to the poor healing of tooth apexes and conducive to early diagnosis and intervention.