RADIOGRAPHIC EVALUATION OF THE SUCCESS OF ROOT CANAL TREATMENT IN MANDIBULAR PREMOLARS: A RETROSPECTIVE CROSS-SECTIONAL STUDY

ERKAL D., ÇAKMAK Y. E., Kopbayeva M., Er K.

Clinical Dentistry and Research, cilt.50, sa.2, ss.160-170, 2026 (TRDizin)

Özet

Background and Aim: Radiographic assessment is essential for evaluating the technical quality of root canal fillings and periapical status after root canal treatment (RCT). This retrospective crosssectional study assessed the radiographic quality of RCT in mandibular premolars using panoramic radiographs and investigated the association between root canal filling quality and periapical lesions. Materials and Methods: Archived digital panoramic radiographs were screened, and 205 radiographs (261 mandibular premolars: 34, 35, 44, 45) were included. Two experienced endodontists independently assessed filling length (adequate: 0-2 mm from radiographic apex; short: >2 mm short; overextended: beyond apex), homogeneity, periapical status (lesion absent/present), and iatrogenic errors. A favorable radiographic outcome required adequate length, homogeneous obturation, no periapical radiolucency, and no iatrogenic errors. Interobserver agreement was calculated using Cohen’s kappa. Multivariable logistic regression with cluster-robust standard errors identified predictors of periapical lesion presence. Results: Overall, 59% of teeth met the predefined radiographic criteria. Periapical lesions were present in 26.1% of teeth. In adjusted analyses, short fillings were strongly associated with lesion presence (P < 0.001), and iatrogenic errors were also significant (p = 0.015). Tooth 35 showed higher odds than tooth 34 (p = 0.003). Inhomogeneous fillings showed a non-significant trend (aOR = 2.27; p = 0.072), while overextension was not associated (p = 0.327). Sensitivity analysis was consistent and additionally supported filling homogeneity as significant (p = 0.036). Conclusion: In mandibular premolars evaluated on panoramic radiographs, 59% of teeth met the predefined radiographic criteria. Short filling and iatrogenic errors were independent predictors of post-treatment periapical lesions, highlighting the importance of accurate working length control and meticulous technique.