Related Experiment Video
Updated: Jun 10, 2026
Effects of Mechanical Methods Used in Peri-implantitis Treatment on Implant Surface Decontamination and Roughness
Published on: March 14, 2025
Frequency and associated factors of segmental root developmental arrest in endodontically treated immature permanent
Jiang Guo1,2, Xi Wei1,2, Junqi Ling1,2
1Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China.
Background:
Segmental root developmental arrest (SRDA) is an uncommon developmental pattern in immature permanent teeth with apical periodontitis, in which a separated apical segment continues to develop independently of the main root. This retrospective study evaluated the frequency, clinical features, and factors associated with SRDA after regenerative endodontic procedures (REPs) or apexification.
Methods:
A total of 103 immature permanent teeth with apical periodontitis treated with REPs or apexification were retrospectively reviewed. Clinical records and radiographs were assessed for SRDA. Data collected included age, sex, tooth type, etiology, Nolla root developmental stage, treatment modality, timing of SRDA detection, and apical inflammation. Associations between candidate factors and SRDA were analyzed using the chi-square test or Fisher exact test, with Bonferroni correction for pairwise comparisons.
Results:
SRDA was identified in 12 of 103 teeth (11.65%). Ten cases occurred in premolars and 2 in incisors; 10 were detected postoperatively and 2 preoperatively. Five affected teeth had undergone apexification and 7 had received REPs. SRDA occurred mainly in teeth at Nolla stage 7 or 8. Univariate analysis showed a significant association between root developmental stage and SRDA occurrence (P = 0.030), with stage 7 teeth significantly more susceptible than stage 9 teeth after Bonferroni correction. Age, sex, tooth type, etiology, and treatment modality were not significantly associated with SRDA.
Conclusion:
SRDA is an uncommon but clinically relevant outcome in immature permanent teeth with apical periodontitis. It may occur before or after treatment and appears to be associated primarily with earlier root developmental stages rather than treatment modality. Long-term radiographic follow-up is warranted.
Related Concept Videos
01:15Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
01:21Tooth Anatomy
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.