影像科学与光化学 ›› 2020, Vol. 38 ›› Issue (1): 73-79.DOI: 10.7517/issn.1674-0475.190712

• 综述与论文 • 上一篇    下一篇

上颌第二磨牙牙冠颊舌径、近远中径和牙面形态的CBCT研究

罗成, 杨馥榕, 雷延颖   

  1. 青海大学附属医院 口腔修复种植正畸科, 青海 西宁 810000
  • 收稿日期:2019-07-18 出版日期:2020-01-15 发布日期:2020-01-15

CBCT Study of Buccal-lingual Diameter, Proximal-distal Mid-diameter and Occlusal Surface Morphology of Maxillary Second Molar Crown

LUO Cheng, YANG Furong, LEI Yanying   

  1. Department of Orthodontics and Prosthodontics, Qinghai University Affiliated Hospital, Xining 810000, Qinghai, P. R. China
  • Received:2019-07-18 Online:2020-01-15 Published:2020-01-15

摘要: 本文通过三维重建上颌第二磨牙的锥形束计算机断层扫描(CBCT)图像,探讨了其牙冠颊舌径、近远中径和牙面形态与牙根及根管类型的关系。收集220例患者(共410颗)上颌第二磨牙的CBCT图像资料,在矢状面放大水平面图像至400%后观察上颌第二磨牙形态,记录牙根、根管数目及融合情况。三维重建上颌第二磨牙的CBCT图像,观察及测量牙冠部和牙面形态,分析牙冠颊舌径、近远中径和牙面形态与牙根及根管类型的关系。结果显示,200例两侧都存在上颌第二磨牙的研究对象中,88%(176/200)根管类型完全对称。410颗上颌第二磨牙中,46.83%(192/410)的第二磨牙形态为三根三根管,54.39%(223/410)有三个独立的牙根,42.20%(173/410)发生牙根融合,82.44%(338/410)为三根管。不同根管类型的上颌第二磨牙牙冠颊舌径存在差异(P<0.05),单根管的上颌第二磨牙牙冠近远中径存在差异(P<0.05),其余各根管类型的上颌第二磨牙牙冠近远中径无显著差异(P>0.05)。410颗上颌第二磨牙中,牙面形态分类为:斜方形64.15%(263/410)、方圆形11.95%(49/410)、圆三角形13.17%(54/410)、卵圆形10.73%(44/410)。其中,圆三角形的牙根多为单根和双根,卵圆形的多为双根,而方圆形和斜方形的则多为三根。不同牙根数目的上颌第二磨牙牙面形态存在差异(P<0.05)。研究结果显示,上颌第二磨牙牙冠颊舌径、近远中径和牙面形态与牙根及根管类型存在一定的联系,临床中可通过三维重建上颌第二磨牙的CBCT图像,利用牙冠的解剖形态来判断上颌第二磨牙牙根及根管类型,为根管治疗提供参考。

关键词: 上颌第二磨牙, 锥形束计算机断层扫描, 牙冠解剖形态, 根管治疗

Abstract: The relationships between crown buccal-lingual diameter, proximal-distal mid-diameter and occlusal surface morphology and root and root canal types of maxillary second molars was studied by three-dimensional reconstruction of CBCT images. The CBCT images of 220 patients (410 maxillary second molars) were collected. The morphology of maxillary second molars was observed after enlarging the horizontal images to 400% on sagittal plane, and the number of root canals and fusion were recorded. Three-dimensional reconstruction of the CBCT images of the maxillary second molars was performed to observe and measure the morphology of the crown and occlusal surface, and to analyze the relationship between the buccal and lingual diameters, distal and distal diameters of the crown and occlusal surface morphology and root and root canal types. Of 200 subjects with maxillary second molars on both sides, 88% (176/200) had completely symmetrical root canal types. Of 410 maxillary second molars, 46.83% (192/410) had three root canals, 54.39% (223/410) had three independent root canals, 42.20% (173/410) had root fusion, and 82.44% (338/410) had three root canals. The buccal and lingual diameters of the crowns of the maxillary second molars with different root canal types were different (P<0.05). The proximal and distal diameters of the crowns of the maxillary second molars with single root canal were different (P<0.05). There was no significant difference in the proximal and distal diameters of the crowns of the other root canal types (P>0.05). Among 410 maxillary second molars, occlusal surface morphology was classified as oblique 64.15% (263/410), square 11.95% (49/410), circular triangle 13.17% (54/410), oval 10.73% (44/410). Among them, the root of the round triangle is mostly single and double, the oval is mostly double, and the square and oblique are mostly three. The occlusal morphology of maxillary second molars with different root numbers was different (P<0.05). In a word, the buccal and lingual diameters, distal and distal diameters and occlusal surfaces of maxillary second molars are related to root and root canal types. Three-dimensional reconstruction of CBCT images of maxillary second molars can be used to determine the root and root canal types of maxillary second molars by using the anatomical morphology of crowns, which can provide a reference for root canal therapy.

Key words: maxillary second molar, cone beam computed tomography, anatomical morphology of crown, root canal therapy