The diagnostic efficacy of cone beam CT for impacted teeth and associated features: a systematic review

Summary This review evaluates the evidence for the diagnostic efficacy of cone beam computed tomography (CBCT) for impacted teeth and associated features. PubMed, Embase and the Cochrane Library were searched using specific indexing terms and reference lists were hand searched. Two reviewers selected relevant publications on the basis of pre‐determined inclusion criteria. Original studies were assessed using a modification of the quality assessment of diagnostic accuracy studies (QUADAS) tool. The literature search yielded 96 titles, of which 7 were included in the review. There was only limited evidence for diagnostic efficacy expressed as sensitivity, specificity and predictive values. Only two studies compared CBCT and panoramic radiographs with a valid reference method and presented the results in terms of percentage of correct diagnoses. This review reveals a need for studies that meet methodological standards for diagnostic efficacy of CBCT in the diagnosis of impacted teeth.     

曲面断层片和锥形束CT对上颌阻生尖牙的定位分析

目的:通过对曲面断层片中上颌阻生尖牙近远中向和垂直向的影像学分区,判定其与锥形束CT (cone-beam computed tomography, CBCT)中相应尖牙唇腭侧位及相邻恒切牙根吸收之间的关系。方法:对68例患者的94颗上颌阻生尖牙进行曲面断层片的拍摄和CBCT扫描。将曲面断层片中上颌阻生尖牙近远中向牙尖所处的位置分为5区(Ⅰ区-Ⅴ区),将牙冠所处的垂直向高度分为3部分(牙冠段,根中段,根尖段),其唇腭侧位置和相邻恒切牙的根吸收情况则由CBCT判定。结果:曲面断层片中上颌阻生尖牙近远中向的区域定位与CBCT中相应阻生牙的唇腭侧位之间有显著相关(P＜0.001),唇侧阻生的尖牙常出现在曲面断层片中的Ⅰ、Ⅱ、Ⅲ区域,正中牙槽阻生的多在Ⅳ区域,腭侧阻生的常在Ⅴ区域,而垂直向的分段与之无显著相关。CBCT中相邻恒切牙的根吸收常发生在Ⅳ、Ⅴ区域和根中段、根尖段。曲面断层片中阻生尖牙近远中向和垂直向的区域划分均与CBCT中相邻恒切牙的根吸收之间有统计学意义(P＜0.05)结论:利用曲面断层片中上颌阻生尖牙近远中向的区域定位可以预测其唇腭侧位和相邻恒切牙的根吸收,垂直向的分段可用来判断相邻恒切牙的根吸收,而不可推测其唇腭侧阻生情况。     

锥形束CT与传统影像学检查在埋伏牙定位诊断上的对比分析

治疗埋伏牙前常常需要判断其在颌骨内的位置、牙体形态、与邻牙及上颌窦的位置关系等,以便确定正确的手术方案。锥形束CT（CBCT）是近年来发展起来的一项新的影像技术,能够快速提供准确的三维图像,弥补了传统平面影像的诸多不足。本文就传统平面影像和CBCT在埋伏牙定位诊断上的优缺点作一综述,以期为临床应用提供帮助。     

锥形束CT在治疗上颌前牙区埋伏牙中的应用

目的:探讨锥形束CT(CBCT)在治疗上颌前牙区埋伏牙中的临床应用价值。方法:收集我院2009—2010年经普通X线片确定有埋伏牙,但不易具体定位的患者11例,进行CBCT扫描和三维重建,确定埋伏牙在颌骨内的具体位置。结果:经CBCT扫描、三维重建后,所有患者均可直观再现埋伏牙的形态、数目、在颌骨中的具体位置和发育情况。11例患者共16颗埋伏牙,其中既有埋伏阻生牙又有埋伏多生牙,3例(4颗)为埋伏多生牙,1例有2颗埋伏牙;2例为倒置埋伏,2例为水平埋伏,3例为垂直埋伏,4例为斜位埋伏。根据CBCT结果制订治疗方案,获得满意的治疗效果。结论:CBCT三维重建对于上颌前牙区埋伏牙治疗方案的设计及实施具有重要意义。     

锥形束CT在诊治阻生牙所致邻牙牙根外吸收中的应用

目的 探讨锥形束CT（CBCT）在阻生牙所致邻牙牙根外吸收诊治中的应用价值。方法 选择2011年1-12月广州军区武汉总医院口腔科诊治,经全口曲面体层片确定存在阻生牙,邻牙牙根外吸收情况不明确的患牙19颗（15例）。所有患者进行CBCT扫描和三维重建,确定牙根外吸收的部位及程度。结果 经CBCT扫描和三维重建后,所有患者均直观显示牙根外吸收的部位及程度,以及阻生牙在颌骨中的三维位置及其与周围重要组织的关系。结论 CBCT可直观、准确地显示牙根外吸收的部位和程度,对阻生牙所致邻牙牙根外吸收的诊断和治疗提供可靠信息。     

锥束CT多方式三维重建在上颌埋伏前牙定位中的应用

目的评价锥束CT三维重建在上颌埋伏前牙定位中的应用价值。方法对48例常规拍摄全颌曲面断层片和根尖片后不能准确判断埋伏牙的形态、位置及与邻牙关系的患者应用锥束CT进行扫描,再采用最大密度投影法（MIP）、多平面重建（MPR）、容积再现法（VR）获得立体三维图像,显示上颌埋伏前牙的形态、位置及与邻牙关系。运用正畸开辟间隙和外科暴露联合正畸牵引导萌术,结合直丝弓矫治技术,直接粘贴托槽牵引导萌上颌埋伏牙。结果经三种方式重建处理后,48例病例均清晰显示上颌埋伏前牙的形态、位置及与邻牙关系。结论锥束CT多方式三维重建为上颌埋伏前牙定位诊断提供更为客观的依据。     

Failure of treatment of impacted canines associated with invasive cervical root resorption

Objectives:To propose invasive cervical root resorption (ICRR) as an unrecognized and/or overlooked etiologic factor in the failure of response of an impacted tooth to orthodontic traction and to underline the importance of cone beam computerized tomography (CBCT) for early and accurate diagnosis of ICRR.Materials and Methods:Fourteen patients (age 13–21 years) with impacted canines (15 canines) that had failed to respond to orthodontic forces and that exhibited ICRR formed the case series for this investigation. The initial diagnosis, treatment, clinical and radiographic expression of failure, and adverse effects on adjacent teeth were analyzed.Results:Initial diagnosis had been performed on plane radiographs. The orthodontist was absent during surgery in 11 patients. Nine canines had been exposed by open procedures. ICRR was not related to the severity of impaction. Its diagnosis was made on existing radiographs, new films, and/or new CBCT. The severity of the lesions was Class 3 or 4, and the teeth were finally extracted. Loss of anchorage characterized 11 patients. Apical resorption of the roots of adjacent teeth was diagnosed in 9 patients.Conclusions:ICRR is a frequently undiagnosed or unrecognized cause of failure of orthodontic resolution of impacted canines and should be distinguished from replacement resorption. CBCT should be used for its early detection and accurate assessment of potential damage to adjacent anchor teeth.     

上颌阻生尖牙患者寰椎形态变异情况的锥形束CT研究

目的 利用锥形束CT(cone-beam computed tomography,CBCT)研究上颌尖牙唇(腭)侧阻生(BIC/PIC)的患者寰椎形态变异的发生情况,以期辅助上颌阻生尖牙的预测和早期干预。方法 选取196例上颌阻生尖牙患者(研究组)和196例年龄、性别、安氏分类与之相匹配的尖牙正常萌出者(对照组)。将所有样本的CBCT导入Dolphin软件,重建头颅侧位片和三维图像,观察并记录各组寰椎后桥及寰椎后弓发育缺陷(包括寰椎后弓发育不全和寰椎后椎弓裂隙)的发生情况,并使用SPSS软件进行统计分析。结果 研究组寰椎后桥的发生率为32.6%,显著高于对照组(22.4%,P=0.024)。PIC组寰椎后桥发生率显著高于对照组(P=0.005),BIC组和对照组、BIC和PIC组之间无统计学差异(P>0.05)。寰椎后弓发育缺陷研究组和对照组之间的发生率并无统计学差异(P>0.05)。结论 上颌尖牙阻生患者较尖牙正常萌出者更容易发生寰椎后桥。     

The detection and management of root resorption lesions using intraoral radiography and cone beam computed tomography – an in vivo investigation

Aim  To compare the accuracy of intraoral periapical radiography with cone beam computed tomography (CBCT) for the detection and management of resorption lesions.
Methodology  Digital intraoral radiographs and CBCT scans were taken of patients with internal resorption ( n  = 5), external cervical resorption ( n  = 5) and no resorption (controls) ( n  = 5). A 'reference standard' diagnosis and treatment plan was devised for each tooth. Sensitivity, specificity, positive predictive values, negative predictive values and receiver operator characteristic (ROC) curves, as well as the reproducibility of each technique were determined for diagnostic accuracy and treatment option chosen.
Results  The intraoral radiography ROC Az values were 0.780 and 0.830 for diagnostic accuracy of internal and external cervical resorption respectively. The CBCT ROC Az values were 1.000 for both internal and external cervical resorption. There was a significantly higher prevalence ( P  = 0.028) for the correct treatment option being chosen with CBCT (%) compared with intraoral radiographs (%).
Conclusion  CBCT was effective and reliable in detecting the presence of resorption lesions. Although digital intraoral radiography resulted in an acceptable level of accuracy, the superior accuracy of CBCT may result in a review of the radiographic techniques used for assessing the type of resorption lesion present. CBCT's superior diagnostic accuracy also resulted in an increased likelihood of correct management of resorption lesions.     

Two- versus three-dimensional imaging in subjects with unerupted maxillary canines

The aim of this study was to evaluate whether there is any difference in the diagnostic information provided by conventional two-dimensional (2D) images or by three-dimensional (3D) cone beam computed tomography (CBCT) in subjects with unerupted maxillary canines. Twenty-seven patients (17 females and 10 males, mean age 11.8 years) undergoing orthodontic treatment with 39 impacted or retained maxillary canines were included. For each canine, two different digital image sets were obtained: (1) A 2D image set including a panoramic radiograph, a lateral cephalogram, and the available periapical radiographs with different projections and (2) A 3D image set obtained with CBCT. Both sets of images were submitted, in a single-blind randomized order, to eight dentists. A questionnaire was used to assess the position of the canine, the presence of root resorption, the difficulty of the case, treatment choice options, and the quality of the images. Data analysis was performed using the McNemar-Bowker test for paired data, Kappa statistics, and paired t-tests. The findings demonstrated a difference in the localization of the impacted canines between the two techniques, which can be explained by factors affecting the conventional 2D radiographs such as distortion, magnification, and superimposition of anatomical structures situated in different planes of space. The increased precision in the localization of the canines and the improved estimation of the space conditions in the arch obtained with CBCT resulted in a difference in diagnosis and treatment planning towards a more clinically orientated approach.     

青少年埋伏阻生牙CBCT三维定位辅助诊断的临床研究

目的:使用CBCT三维定位分析54颗青少年上颌埋伏阻生牙,为正畸诊疗设计提供精准依据。方法:采用CBCT技术重建54颗青少年上颌埋伏阻生牙,应用CS 3D Imaging软件分析阻生牙位置、牙根情况及与邻牙关系进行测量分析并评价。结果:上颌埋伏阻生牙主要以垂直阻生为主,埋伏高度以牙冠位于邻牙根1/2至根尖占到66.7%;根尖位置以偏于10 mm以内居多;牙骨性粘连占1.9%。最终对54颗埋伏阻生牙牵引45颗,拔除9颗。结论:CBCT可精准三维定位埋伏阻生牙,为正畸临床治疗提供重要依据。     

上颌埋伏尖牙引起切牙牙根吸收的预测

目的:结合锥形束CT(CBCT),通过分析曲面断层片、头颅侧位片,得出上颌埋伏尖牙引起切牙牙根吸收的预测方程。方法:收集符合标准的病例,根据邻近切牙是否发生吸收分成吸收组和未吸收组.所有患者拍摄曲面断层片、头颅侧位片和CBCT并进行测量。结果:确定与切牙牙根是否发生吸收相关的指标,建立切牙牙根吸收预测方程。结论:通过对曲面断层片和头颅侧位片的测量,可初步预测上颌埋伏尖牙是否已造成邻近切牙牙根吸收。中切牙预测方程准确率高,具有一定临床意义;侧切牙预测准确率较低,尚无法应用于临床。     

Cone‐Beam Computed Tomography for Detection of Intrabony and Furcation Defects: A Systematic Review Based on a Hierarchical Model for Diagnostic Efficacy

Background: The aim of this review is to assess the diagnostic efficacy of cone‐beam computed tomography (CBCT) for the diagnosis of and/or treatment planning for intrabony and furcation defects, using a well‐known six‐tiered hierarchical model for diagnostic efficacy. Methods: The MEDLINE, EMBASE, and Cochrane Library bibliographic databases were searched until August 2015 for studies evaluating CBCT imaging for the diagnosis of and/or treatment planning for intrabony and/or furcation defects. The search strategy was restricted to English language publications using the combination of MeSH terms, free terms, and key words. Results: The search strategy yielded 16 publications that qualitatively or quantitatively evaluated the use of CBCT for the detection of intrabony and/or furcation defects and how CBCT influenced the diagnosis and/or treatment plan. According to Quality Assessment of Studies of Diagnostic Accuracy‐2, all included studies were medium to low risk of bias. The review identified only one study that investigated the societal efficacy, and none evaluated the patient outcome efficacy or therapeutic efficacy. One study investigated the diagnostic thinking efficacy. All other included studies investigated the diagnostic accuracy of CBCT. Conclusions: From the assessed studies, it can be concluded that there is not sufficient scientific evidence to justify the use of CBCT for the diagnosis of and/or treatment planning for intrabony and furcation defects. Furthermore, the effectiveness of CBCT for such diagnostic tasks has been assessed only at low diagnostic efficacy levels.     

Diagnosis of Vertical Root Fractures by Cone-beam Computed Tomography in Root-filled Teeth with Confirmation by Direct Visualization: A Systematic Review and Meta-Analysis

IntroductionThe purpose of this review was to determine the diagnostic accuracy of cone-beam computed tomographic (CBCT) imaging in detecting vertical root fractures (VRFs) in root-filled teeth compared with a reference standard (direct visualization).MethodsElectronic searches were performed in Medline, Scopus, Cochrane, and gray literature for English language articles until June 2020. Prospective and retrospective clinical studies using CBCT imaging to diagnose VRFs in root-filled teeth were included. Case reports and in vitro studies were excluded. The Quality Assessment of Diagnostic Accuracy Studies 2 tool was used to assess the risk of bias and applicability concerns. Meta-analysis was performed using Stata 16.1 software (StataCorp, College Station, TX) via the MIDAS v.3.0 package and METANDI module. Publication bias was evaluated using Deeks’ funnel plot analysis. Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was performed to evaluate the certainty of evidence. This systematic review was registered in the Open Science Framework (10.17605/OSF.IO/7JKE2).ResultsEight articles were included in this systematic review and meta-analysis. Risk of bias assessment showed that 5 articles in the patient selection domain had low risk of bias with low applicability concern. In the index test and reference standard domains, 7 articles had moderate risk of bias with moderate applicability concern. Three articles had high RB in the flow and timing domain. There was no publication bias. CBCT imaging had a pooled sensitivity and specificity of 0.78 (95% confidence interval [CI], 0.64–0.88) and 0.80 (95% CI, 0.63–0.91), respectively, and an accuracy of 0.86 (95% CI, 0.83–0.89). CBCT imaging also had pooled positive and negative likelihood ratios of 4 and 0.2, respectively. In GRADE analysis, the quality of evidence was low for sensitivity and moderate for specificity when CBCT imaging was used for the diagnosis of VRF.ConclusionsThe overall quality assessment of the included articles showed that in the patient selection domain, the risk of bias was low, and it was moderate in the index test and reference standard domains. Evidence from this systematic review and meta-analysis indicates that CBCT imaging is still not a good tool for diagnosing VRFs in root-filled teeth compared with direct visualization.     

CBCT在诊治埋伏阻生牙中的应用

目的:探讨CBCT在埋伏阻生牙诊治中的应用。方法:对56例(37颗多生牙、41颗阻生牙)经全景片检查需进一步明确诊断的埋伏阻生牙,进行CBCT扫描,通过三维重建、矢状位、冠状位及轴位断层进行分析。结果:与全景片比较,CBCT能准确定位埋伏阻生牙的位置、生长方向、数量,准确率差异有统计学意义(P<0.05)。结论:CBCT可以更直观、准确地对埋伏阻生牙定位,特别是在上颌前牙区的临床诊治更有应用价值。     

单侧上颌尖牙阻生对牙颌三维结构的影响

目的: 采用锥形束CT（CBCT）研究单侧尖牙阻生病例牙颌的三维结构特征,评估发生上颌尖牙阻生的相关风险因素,为正畸临床早期干预提供依据。方法: 选取30例单侧上颌尖牙阻生患者的CBCT,利用Romexis软件进行三维重建,测量、比较两侧牙颌三维结构特征指标,采用SPSS17.0软件包进行配对t检验和相关数据的回归分析。结果: 阻生侧尖牙和侧切牙倾斜度明显增大,尖牙牙冠更向近中、侧切牙向远中倾斜（P<0.001）;阻生侧尖牙体积更大、侧切牙体积更小（P<0.05）,当尖牙体积增大或侧切牙体积减小时,上颌尖牙的阻生概率增加;阻生侧牙弓弧形长度更短,牙弓宽度在尖牙区和前磨牙区更短（P<0.001）,而宽度在磨牙区无显著差异（P>0.05）,两侧牙弓长度在尖牙区、前磨牙区和磨牙区无显著差异（P>0.05）。结论: 上颌尖牙阻生伴随或导致同侧牙及牙槽骨三维方向发育异常,上颌尖牙阻生的严重程度与周围牙颌结构异常密切相关,提示上颌尖牙阻生可以早期预判、诊断,且可以实施有效的早期干预。     

CBCT与DR根尖片在根折诊断中的应用比较研究

目的：对比锥形束CT（CBCT）与数字化根尖片（DR）对根折诊断的准确性,评价是根折诊断中的应用价值。方法：收集临床症状怀疑为根折,并最终确诊的患牙50颗。经由两名有临床经验的牙体牙髓科医生及一名放射科医生共同对其DR根尖片和CBCT进行阅片得出诊断结果,比较两种方法在根折诊断上的差异性和准确度。结果：50颗根折患牙,CBCT检出率100％,DR检出率20％。 CBCT与DR在根折诊断的准确性上有显著差异。结论：相对于DR,CBCT在根折诊断的准确度上有显著优势。     

Comparative study of cone beam computed tomography and intraoral periapical radiographs in diagnosis of lingual-simulated external root resorptions

Abstract – Background: Owing to a lack of symptoms and difficult visualization in routine intraoral radiographs, diagnosis of external root resorptions can be challenging. Aim: The goal of this study was to compare two image acquisition methods, intraoral radiographs and cone beam computed tomography (CBCT), in the diagnosis of external resorption. Material and Methods: Thirty‐four maxillary and mandibular bicuspids were divided into three groups. Perforations measuring 0.3 and 0.6 mm in diameter and 0.15 and 0.3 mm in depth, respectively, were made on the lingual root surfaces in thirty teeth, and four were used as controls. Next, teeth were mounted on an apparatus and radiographed at mesial, distal, and orthoradial angulations. CBCT images were also taken. The analysis of the intraoral radiographic and tomographic images was carried out by two experts using standardized scores. Data were then compared statistically. Results: A strong agreement between the examiners was observed in both diagnosis methods, the intraoral radiographic (r = 0.93) and the tomographic analysis (r = 1.0). Tomography had higher statistically significant detection values than intraoral radiography (P < 0.05). In intraoral radiographs, the detection was significantly greater (P < 0.05) in the mandibular bicuspids, compared with their maxillary counterparts. The ability to detect 0.6‐mm perforations by intraoral radiography was significantly higher than that of 0.3‐mm perforations (P < 0.05). Conclusion: Cone beam computed tomography showed better diagnostic ability compared with intraoral radiography, regardless of the tooth or the dimensions of the resorption evaluated.     

基于锥形束CT的多生牙新分类方法临床意义研究

目的　应用锥形束CT（cone-beam CT,CBCT）对多生牙进行新的临床分类,并分析新分类方法的临床意义。方法　收集2016—2019年首都医科大学附属北京友谊医院口腔科的CBCT影像资料5100例,其中多生牙患者209例,共计多生牙278颗。应用CBCT对多生牙进行新的临床分类,包括萌出型、骨埋伏高位型、骨埋伏低位型、骨埋伏复杂型和牙弓外型,并分析其临床意义。结果　（1）临床资料分析：多生牙发生率为4.1%,其中有1颗多生牙的患者占76.6%,有2颗多生牙的患者占19.1%,有3颗及以上多生牙的患者占4.3%。多生牙好发部位依次为：上颌切牙区、上颌磨牙区、下颌尖牙及前磨牙区、上颌尖牙及前磨牙区、下颌磨牙区。34.9%的多生牙对邻近恒牙产生了继发影响,以萌出错位及阻生为主,主要发生在上颌切牙区。（2）新分类方法的临床意义分析：上颌切牙区多生牙以骨埋伏低位型及萌出型为主,尖牙、前磨牙及磨牙区多生牙以萌出型为主。不同类型多生牙对邻近恒牙产生继发影响的发生率不同或不全相同（χ2 = 26.057,P < 0.001）,提示对邻近恒牙易产生继发影响的多生牙类型依次为：萌出型、骨埋伏复杂型、骨埋伏高位型、牙弓外型、骨埋伏低位型。结论　基于CBCT的多生牙新分类方法简单实用,其中萌出型、骨埋伏复杂型及骨埋伏高位型多生牙更易产生错牙合畸形,建议尽早拔除多生牙、定期随访,必要时正畸治疗。     

基于锥形束CT的多生牙新分类方法临床意义研究

 目的　应用锥形束CT（cone-beam CT，CBCT）对多生牙进行新的临床分类，并分析新分类方法的临床意义。方法　收集2016-2019年首都医科大学附属北京友谊医院口腔科的CBCT影像资料5100例，其中多生牙患者209例，共计多生牙278颗。应用CBCT对多生牙进行新的临床分类，包括萌出型、骨埋伏高位型、骨埋伏低位型、骨埋伏复杂型和牙弓外型，并分析其临床意义。结果　（1）临床资料分析：多生牙发生率为4.1%，其中有1颗多生牙的患者占76.6%，有2颗多生牙的患者占19.1%，有3颗及以上多生牙的患者占4.3%。多生牙好发部位依次为：上颌切牙区、上颌磨牙区、下颌尖牙及前磨牙区、上颌尖牙及前磨牙区、下颌磨牙区。34.9%的多生牙对邻近恒牙产生了继发影响，以萌出错位及阻生为主，主要发生在上颌切牙区。（2）新分类方法的临床意义分析：上颌切牙区多生牙以骨埋伏低位型及萌出型为主，尖牙、前磨牙及磨牙区多生牙以萌出型为主。不同类型多生牙对邻近恒牙产生继发影响的发生率不同或不全相同（χ2 = 26.057，P < 0.001），提示对邻近恒牙易产生继发影响的多生牙类型依次为：萌出型、骨埋伏复杂型、骨埋伏高位型、牙弓外型、骨埋伏低位型。结论　基于CBCT的多生牙新分类方法简单实用，其中萌出型、骨埋伏复杂型及骨埋伏高位型多生牙更易产生错牙合畸形，建议尽早拔除多生牙、定期随访，必要时正畸治疗。