ArticleBMC oral health2022
Variations of root and canal morphology of mandibular second molars in Chinese individuals: a cone-beam computed tomography study.
Article in BMC oral health, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers, 1 of them a synthesis that pooled it.
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17 citing papers in PubMed, 1 synthesis or guideline pooled it, 26 citations in OpenAlex.
- Prevalence of c-shaped canal morphology in premolar and molar teeth assessed by cone-beam computed tomography: systematic review and meta-analysis.BMC oral health · 2025Pooled it
- Accessory Apical Foramina in Mandibular Second Molars with Mesial and Distal Root Canal Systems: An Ex Vivo Micro-CT Morphometric Study.Journal of clinical medicine · 2026Article
- C-Shaped Root Canal Morphology in Mandibular Posterior Teeth-A Retrospective CBCT Study Based on Two Classification Systems.Diagnostics (Basel, Switzerland) · 2026Article
- Relationship between C-shaped root canal configuration in mandibular second molars and radix entomolaris in mandibular first molars: a CBCT-based study in a Western Chinese population.Clinical oral investigations · 2026Article
- Root canal and nasopalatine canal morphology in a Guangxi population: a cone-beam CT study on regional variations.BMC oral health · 2026Article
- Cone-beam computed tomography analysis of maxillary premolar canal anatomy: Ahmed's versus Vertucci's classifications in a Jordanian cohort.Restorative dentistry & endodontics · 2026Article
- Bilateral Occurrence of Mandibular Permanent Second Molar With Four Roots: A Case Report and Literature Review.Case reports in dentistry · 2026Article
- Expert consensus on management of instrument separation in root canal therapy.International journal of oral science · 2025Review
- C-shaped canal configuration in mandibular second molars of a selected Uyghur adults in Xinjiang: prevalence, correlation, and differences of root canal configuration using cone-beam computed tomography.BMC medical imaging · 2025Article
- Anatomical features of mandibular second molar C-shaped root canals in a Chinese population: a CBCT analysis.Surgical and radiologic anatomy : SRA · 2025Article
- Literature review and case study: unveiling the complexities of mandibular second molar with three distal canals.BMC oral health · 2024Review
- Article
- Analysis of mandibular molar anatomy in Taiwanese individuals using cone beam computed tomography.Journal of dental sciences · 2024Article
- Microcomputed tomography (micro-CT) analysis of apical mandibular premolar in relation to clinical sign presentation: An in vitro study.The Saudi dental journal · 2024Article
- Morphological analysis of anterior permanent dentition in a Chinese population using cone-beam computed tomography.Head & face medicine · 2023Article
- Comparison of five single-file systems in the preparation of severely curved root canals: an ex vivo study.BMC oral health · 2022Article
- Mandibular Second Premolar with Four Canals: A Case Report.Iranian endodontic journal · 2022Article
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe mandibular second molars demonstrate variations on root and canal morphology. The aim of this study was to investigate all the root canal morphology of mandibular second molars and analyze the morphological variations in patients by gender and age in a Chinese population use CBCT imaging.
methodsCone-beam computed tomographic images of 1200 bilateral mandibular second molars were obtained from 600 patients (300 females and 300 males) who required a preoperative assessment for implant surgery, surgical removal of impacted teeth, orthodontic treatment, surgery of maxillofacial tumour and cysts or LeFort I osteotomy. CBCT images were divided into 5 groups according to age: "15-24 years", "25-34 years", "35-44 years", "45-54 years" and "≥ 55 years"; and 2 groups by gender: "females" and "males". The following information were recorded: the number of roots and canals and their morphology, the frequency and configuration of C-shaped canals by gender, age and position (left and right). The chi-square test was used to analyse differences between groups. P value of < 0.05 was considered statistically significant.
resultsOf the 1200 teeth, 61% had two separate roots located mesiodistally, 35.6% had one C-shaped root. The 45.3% teeth had three canals in two-rooted mandibular second molars. The mesial root showed a Vertucci type II configuration in 28.9% cases followed by type IV(24.4%). While the distal root showed a significant higher prevalence of type I configuration in 95.6%. In the examined 1200 teeth, 430 teeth (35.8%) had C-shaped root canals. The prevalence of C-shaped root canal systems was significantly higher in females (42.5%) than in males (29.1%) (P = 0.000), and did not differ with age (P = 0.126). The 80.4% C-shaped canals were bilateral (P = 0.000) and did not differ with side (left and right) (P = 0.758).
conclusionsThe most commonly observed root morphology for the mandibular second molars was 2 separate roots with three canals.The prevalence of C-shaped root canal is 35.8% and is more higher in females than in males.
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