AIM To analyse the prevalence of periapical lesions and their association with previous root canal treatment, root canal filling length and type of coronal restoration using in vivo cone-beam computed tomographic (CBCT) assessment. METHODOLOGY A global sample of 20 836 teeth, with a combined total of 27 046 roots, from 1160 patients, was analysed via CBCT assessment in eight health centres. Each tooth was evaluated by one out of five examiners after having performed a defined calibration procedure on the basis of 319 teeth. Intra- and inter-rater reliability tests were performed. Each tooth was classified according the tooth number, presence/absence of periapical lesions, presence/absence of previous root canal treatment, length of root canal filling (short, good or overfilling) and type of coronal restoration. The z-test for proportions was used to analyse differences between tooth subgroups, and an odds ratio was determined in order to analyse the association between treatment status and periapical lesions. A P < 0.05 was considered significant. RESULTS At a tooth level, the overall prevalence of periapical lesions in the sample was 10.4%. Maxillary teeth were associated with a significantly larger percentage of lesions (13.1%), whilst maxillary first molars had the greater proportion of lesions (21.2%). The prevalence of periapical lesions was significantly larger in root filled teeth (55.5%), short root canal fillings (72.7%) and in teeth restored with crowns (46.1%). At a root level, the mesiobuccal roots of both maxillary first molars had a tendency for a larger percentage of periapical lesions. CONCLUSION History of root canal treatment, root canal filling length and type of coronal restoration influenced the presence of periapical lesions. Molars were more commonly associated with periapical lesions on root filled teeth, particularly those with short root fillings and those with crowns.

中文翻译：

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根尖周炎的患病率及其与以前的根管治疗，根管充盈长度和冠状修复体类型的关系-一项横断面研究。

目的使用体内锥形束计算机断层扫描（CBCT）评估分析根尖周病变的发生率及其与先前的根管治疗，根管充盈长度和冠状修复体类型的关系。方法论通过对八个健康中心的CBCT评估，分析了来自1160名患者的20 836颗牙齿的总样本，总共有27 046根。在基于319颗牙齿执行了定义的校准程序之后，由五位检查者中的每位检查者对每颗牙齿进行了评估。评估者内部和评估者之间进行了可靠性测试。根据牙齿数量，根尖周病变的存在/不存在，以前的根管治疗的存在/不存在，根管充盈的长度（短，好或过充）和冠状修复的类型对牙齿进行分类。Z检验比例用于分析牙齿亚组之间的差异，并确定比值比以分析治疗状态与根尖周病变之间的关联。AP <0.05被认为是显着的。结果在牙齿水平上，样品中根尖周病变的总体患病率为10.4％。上颌牙齿与病变的比例明显更高（13.1％），而上颌第一磨牙的病变比例更高（21.2％）。根管充填的牙齿（55.5％），根管短充填（72.7％）和经冠修复的牙齿（46.1％）的根尖周病变的发生率明显更高。在牙根水平上，两个上颌第一磨牙的近颊颊根都有较大的根尖周病变的趋势。结论根管治疗的历史，根管充盈的长度和冠状修复的类型影响根尖周病变的存在。臼齿更常见于根部充填牙齿的根尖周病变，尤其是那些具有短根充填的牙齿和那些具有牙冠的牙齿。