Hanson Beate P, Cummings Peter, Rivara Frederick P, John Mike T
AO Clinical Investigation and Documentation, AO ASIF Center, Davos Platz, Switzerland.
J Can Dent Assoc. 2004 Jan;70(1):39-43.
To estimate the relative risk of mandibular angle fractures among people with a lower third molar compared with those without a lower third molar.
Data for a case-control meta-analysis were obtained by performing a literature search in MEDLINE and EMBASE to identify suitable observational studies. To be included, studies had to present data on patients with mandibular fractures, incorporate cross-classified information about the presence of a lower third molar and indicate whether the fracture was a mandibular angle fracture on the ipsilateral side.
Six studies, involving 3,002 patients with mandibular fractures, met the inclusion criteria. Crude relative risk estimates for an angle fracture, comparing patients with a third molar with those without, ranged from 1.2 to 12.7. There was evidence of heterogeneity across the 6 studies (p = 0.001), but when 2 studies with less methodologic rigour were excluded, a test of homogeneity was no longer statistically significant (p = 0.22). The estimated relative risk across the remaining 4 studies was 2.4 (95% CI 1.9 to 3.0).
The presence of a lower third molar may double the risk of an angle fracture of the mandible. This could have a bearing on any clinical decision on whether to extract the molar.
评估有下颌第三磨牙者与无下颌第三磨牙者相比发生下颌角骨折的相对风险。
通过检索MEDLINE和EMBASE获取病例对照荟萃分析的数据，以识别合适的观察性研究。纳入的研究必须提供下颌骨折患者的数据，纳入关于下颌第三磨牙存在情况的交叉分类信息，并表明骨折是否为同侧下颌角骨折。
六项研究涉及3002名下颌骨折患者，符合纳入标准。将有第三磨牙的患者与无第三磨牙的患者进行比较，角部骨折的粗相对风险估计值在1.2至12.7之间。六项研究中有异质性证据（p = 0.001），但排除两项方法学严谨性较低的研究后，同质性检验不再具有统计学意义（p = 0.22）。其余四项研究的估计相对风险为2.4（95%可信区间1.9至3.0）。
下颌第三磨牙的存在可能使下颌角骨折的风险加倍。这可能会影响关于是否拔除该磨牙的任何临床决策。
