Abstract：
The indication for removal of asymptomatic fully impacted third molars is still controversial. In this study, radiological and histological investigation of the dental follicle of asymptomatic impacted mandibular third molars was performed, aiming to provide a reference for clinical prophylactic extraction of these teeth.
Patients with impacted mandibular third molars were included and the maximum width of the dental follicle around the crown was measured in horizontal, sagittal and coronal sections by cone beam computed tomography. The dental follicles were stained with haematoxylin-eosin, analysed by a pathologist and classified as normal, inflammatory or cystic. A Chi-squared test was used to analyse the association of the incidence of inflammation and cysts with the clinical variables of the impacted mandibular third molars.
Thirty-seven samples were normal dental follicles; 52 samples showed inflammatory infiltration with an incidence of 57.14%; 2 samples with a maximum dental follicle width of 2-3 mm were diagnosed as odontogenic cysts, and the incidence was 2.20%. There was no significant difference in the incidence of inflammatory and cystic dental follicles between males and females, or between different age groups (P > 0.05). With an increase of the maximum width of the dental follicle, there was a rise in the incidence and degree of infiltration of chronic nonspecific inflammation.
Asymptomatic impacted mandibular third molars tend to be extracted, especially for teeth with a 2-3 mm maximum width of the dental follicle on radiological examination.
Patients with impacted mandibular third molars were included and the maximum width of the dental follicle around the crown was measured in horizontal, sagittal and coronal sections by cone beam computed tomography. The dental follicles were stained with haematoxylin-eosin, analysed by a pathologist and classified as normal, inflammatory or cystic. A Chi-squared test was used to analyse the association of the incidence of inflammation and cysts with the clinical variables of the impacted mandibular third molars.
Thirty-seven samples were normal dental follicles; 52 samples showed inflammatory infiltration with an incidence of 57.14%; 2 samples with a maximum dental follicle width of 2-3 mm were diagnosed as odontogenic cysts, and the incidence was 2.20%. There was no significant difference in the incidence of inflammatory and cystic dental follicles between males and females, or between different age groups (P > 0.05). With an increase of the maximum width of the dental follicle, there was a rise in the incidence and degree of infiltration of chronic nonspecific inflammation.
Asymptomatic impacted mandibular third molars tend to be extracted, especially for teeth with a 2-3 mm maximum width of the dental follicle on radiological examination.
摘要：
目的：切除无症状的完全阻生第三磨牙的指征仍存在争议。在这项研究中,对无症状阻生下颌第三磨牙的牙囊进行了放射学和组织学研究，旨在为临床预防性拔牙提供参考。
方法：包括下颌第三磨牙阻生患者，并在水平方向测量牙冠周围牙囊的最大宽度，锥形束计算机断层扫描的矢状和冠状切面。牙囊用苏木精-伊红染色，由病理学家分析并归类为正常，炎性或囊性。使用卡方检验来分析炎症和囊肿的发生率与下颌第三磨牙阻生的临床变量之间的关系。
结果：37个样本为正常牙囊；52个样本显示炎性浸润，发生率为57.14%；2个样本最大牙囊宽度为2-3毫米，被诊断为牙源性囊肿，发病率为2.20%。炎症和囊性牙囊的发病率在男性和女性之间没有显著差异，或不同年龄组之间(P>0.05)。随着牙囊最大宽度的增加,慢性非特异性炎症的发生率和浸润程度均有上升.
结论：无症状阻生下颌第三磨牙倾向于拔除，特别是对于在放射学检查中最大宽度为2-3毫米的牙齿。
方法：包括下颌第三磨牙阻生患者，并在水平方向测量牙冠周围牙囊的最大宽度，锥形束计算机断层扫描的矢状和冠状切面。牙囊用苏木精-伊红染色，由病理学家分析并归类为正常，炎性或囊性。使用卡方检验来分析炎症和囊肿的发生率与下颌第三磨牙阻生的临床变量之间的关系。
结果：37个样本为正常牙囊；52个样本显示炎性浸润，发生率为57.14%；2个样本最大牙囊宽度为2-3毫米，被诊断为牙源性囊肿，发病率为2.20%。炎症和囊性牙囊的发病率在男性和女性之间没有显著差异，或不同年龄组之间(P>0.05)。随着牙囊最大宽度的增加,慢性非特异性炎症的发生率和浸润程度均有上升.
结论：无症状阻生下颌第三磨牙倾向于拔除，特别是对于在放射学检查中最大宽度为2-3毫米的牙齿。
