Pan Feng, Kau Chung H, Zhou Hong, Souccar Nada
Head Face Med. 2013 Apr 20;9:13. doi: 10.1186/1746-160X-9-13.
To assess the amount of maxillary and mandibular inter-radicular bone mass and determine the most reliable mini-screw placement sites.
Retrospective Cone Beam Computed Tomography (CBCT) images of 40 Angle Class I subjects (20 females, 20 males, aged 16 to 32) were obtained. Measurements on the buccal (BI), medial (MI) and lingual (LI) sides of the inter-radicular spaces were taken at 0, 1, 2, 3, 4, 5 mm from the cemento-enamel junction (CEJ) in an apical direction.
The male and female BI scores ranged from 2.99±0.73 mm to 6.18±1.03 mm and 2.69±0.84 mm to 6.21±1.22 mm respectively. The male and female MI scores ranged from 1.36±0.38 mm to 4.50±0.99 and 1.53±0.66 to 4.77±1.99 mm respectively. LI scores ranged from 2.37±0.70 to 6.47±1.0 mm and 2.45±0.56 mm and 6.66±1.33 mm respectively. In both maxillary and mandibular arch, the inter-radicular space increased in the apical direction except for the buccal and medial inter-radicular spaces between the maxillary first and second molars.
The medial inter-radicular spaces are the decisive parameter for mini-screw placement. In the maxillary arch, regions between central and lateral incisors, lateral incisor and canine, first and second molars are not viable for mini-screw insertion. The residual inter-radicular regions are proper for implantation at 3 mm above the CEJ. In the mandible, the regions between incisors and canines are too narrow for mini-screw insertion and the reliable sites for mini-screws are regions between premolars, molars or first molar and second premolar at 2 mm below the CEJ.
评估上颌和下颌牙根间骨量，并确定最可靠的微螺钉植入部位。
获取40例安氏I类受试者（20名女性，20名男性，年龄16至32岁）的回顾性锥形束计算机断层扫描（CBCT）图像。从牙骨质-釉质界（CEJ）向根尖方向，在牙根间间隙的颊侧（BI）、近中侧（MI）和舌侧（LI），于距离CEJ 0、1、2、3、4、5 mm处进行测量。
男性和女性的BI评分分别为2.99±0.73 mm至6.18±1.03 mm以及2.69±0.84 mm至6.21±1.22 mm。男性和女性的MI评分分别为1.36±0.38 mm至4.50±0.99以及1.53±0.66至4.77±1.99 mm。LI评分分别为2.37±0.70至6.47±1.0以及2.45±0.56至6.66±1.33 mm。在上颌和下颌牙弓中，除上颌第一和第二磨牙之间的颊侧和近中牙根间间隙外，牙根间间隙向根尖方向增大。
牙根间近中间隙是微螺钉植入的决定性参数。在上颌牙弓中，中切牙与侧切牙之间、侧切牙与尖牙之间、第一和第二磨牙之间的区域不适于微螺钉植入。牙根间剩余区域在CEJ上方3 mm处适合植入。在下颌，切牙与尖牙之间的区域对于微螺钉植入过窄，微螺钉的可靠植入部位是前磨牙之间、磨牙之间或第一磨牙与第二前磨牙之间且位于CEJ下方2 mm处的区域。
