Analysis of influencing factors on crown fracture in endodontically treated teeth without crown restorations

doi:10.19439/j.sjos.2026.03.010

Abstract

Abstract: PURPOSE: To investigate the intraoral retention time before crown fracture, the severity of crown fracture, and related influencing factors in endodontically treated teeth (ETT) without crown restoration, and to provide evidence for clinical prognosis evaluation and intervention. METHODS: Patients with ETT crown fractures who visited Shanghai Ninth people's Hospital, Shanghai Jiao Tong University School of Medicine from March 2023 to January 2024 were selected. Through medical history collection and oral examination, the intraoral retention time of ETT, the number of missing axial walls after crown fracture, and patients' baseline clinical data were recorded. Univariate and multivariate logistic regression analyses were used to screen for independent risk factors affecting the intraoral retention time and the severity of crown fracture in ETT. RESULTS: A total of 146 patients were included, consisting of 87 males and 59 females, with an average age of (44.63±4.28) years. Among them, there were 51 maxillary posterior teeth and 95 mandibular molars. The average intraoral retention time of ETT was (8.27±3.57) years, and the average number of missing axial walls was (92.25±0.99). Multivariate analysis showed that age, reason for root canal treatment, filling material, jaw position, tooth position, and periodontal status were independent risk factors for shorter intraoral retention time of ETT (P<0.05). Reason for root canal treatment, jaw position, and tooth position were independent risk factors for the severity of ETT crown fracture (number of missing axial walls) (P<0.05). CONCLUSIONS: The retention time of teeth after root canal treatment is correlated with patients' age, reason for root canal treatment, tooth position, and periodontal status. Elderly patients, teeth undergoing root canal treatment due to dental trauma or cracked teeth, mandibular molars, and teeth with poor periodontal status have a higher risk of crown fracture without crown restoration after root canal treatment.

Key words: Endodontically treated teeth, Crown fracture, Crown restoration, Intraoral retention time, Tooth defect, Influencing factors

CLC Number:

R781.05

Zhu Jiajun, Wang Yi, Yang Ya. Analysis of influencing factors on crown fracture in endodontically treated teeth without crown restorations[J]. Shanghai Journal of Stomatology, 2026, 35(3): 281-287.

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