CBCT Study on Relationship between Roots of Maxillary Second Molars and Maxillary Sinus Floor

doi:10.13701/j.cnki.kqyxyj.2026.10.007

Abstract

Abstract: Objective: To analyze the relationship between the roots of the maxillary second molar (MSM) and the maxillary sinus floor using cone-beam computed tomography (CBCT). Methods: CBCT images of 660 MSMs from 330 patients were retrospectively analyzed. A total of 427 three-rooted MSMs were identified. The vertical distances from the mesio-buccal root, disto-buccal root, and palatal root to the maxillary sinus floor were measured in the sagittal and coronal planes. The Friedman test and the Wilcoxon signed-rank test were employed for statistical analysis. Results: For the three-rooted MSMs, the distances from the three roots to the maxillary sinus floor showed statistically significant differences in both the coronal and sagittal planes (P＜0.05). Pairwise comparisons consistently revealed the order: mesio-buccal root < disto-buccal root < palatal root (P＜0.05). Conclusion: In the spatial relationship between three-rooted MSMs and the maxillary sinus floor, the mesio-buccal root is the closest to the maxillary sinus floor, while the palatal root is the farthest. The results would provide anatomical reference for root canal therapy and microscopic apical surgery of MSM.

Key words: maxillary second molar, maxillary sinus, cone-beam computed tomography

SONG Xinyu, CUI Bo, WANG Xiuhui, WU Xiaoyu, MENG Xinyu, LIU Rubing, CUI Caiyun. CBCT Study on Relationship between Roots of Maxillary Second Molars and Maxillary Sinus Floor[J]. Journal of Oral Science Research, 2026, 42(10): 867-871.

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