Effect of field of view in the detection of chemically created peri-implant bone defects in bovine ribs using cone beam computed tomography: an in vitro study.

OBJECTIVES: To assess the accuracy of cone beam computed tomography (CBCT) using two fields of view (FOVs) in the diagnosis of peri-implant defects. STUDY DESIGN: Eighty implants were placed in bovine ribs, in which peri-implant bone defects of two sizes (T1 and T2) were simulated using 70% perchloric acid. CBCT images were acquired with the use of two FOV size settings of the i-CAT NG unit: 6 × 16 cm and 8 × 8 cm. One oral and maxillofacial surgeon (OMS) and two oral and maxillofacial radiologists (OMRs) evaluated the presence of defects, and their findings were compared with direct visual evaluation. The kappa (κ)-statistic, area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the examinations were calculated. AUC values were compared with the Student t test. RESULTS: The obtained κ-values indicated good intra- and interobserver agreement. A significant difference was found between T1 and T2 (P = .01) with regard to AUC values, and no significant difference was found between the different FOVs in both test groups (T1, P = .06; T2, P = .33). The sensitivity, specificity, PPV, and NPV of the examinations were higher for the OMRs than for the OMS involved in the study. CONCLUSIONS: The ability of CBCT to detect chemically created peri-implant bone defects was good, especially for larger defects (Group T2) but only for the observations of the OMRs. The observations of the OMS were less accurate. The two FOVs tested were appropriate to detect peri-implant bone defects.

CBCT-based evaluation of integrity of cortical sinus close to periapical lesions.

The purpose of the present study was to test the applicability of cone beam computed tomography (CBCT) to evaluate the integrity of the cortical sinus close to periapical lesions. Two observers analyzed samples of 64 alveoli of first molar roots in macerated swine maxillas prepared with perchloric acid to simulate periapical lesions. The specimens were evaluated using CBCT (55-mm high and 100-mm diameter cylinder at 0.2-mm voxel resolution) for the presence of oroantral communication (OAC) caused by the simulated lesions. Sensitivity, specificity, and accuracy were calculated. Fair values were obtained for accuracy (66%-78%) and good values for specificity (70%-98%), whereas the values for sensibility showed relevant variation (41%-78%). For this reason, the interobserver agreement score was weak. CBCT proved capable of evaluating the integrity of the cortical sinus (absence of oroantral communication) when it lies close to an apical periodontitis lesion. However, the low interobserver agreement reflects the difficulty in performing diagnoses when OAC is adjacent to a periapical lesion, using the acquisition protocol adopted in this research. This could be attributed to the high level of image noise.

CBCT-based evaluation of integrity of cortical sinus close to periapical lesions

The purpose of the present study was to test the applicability of cone beam computed tomography (CBCT) to evaluate the integrity of the cortical sinus close to periapical lesions. Two observers analyzed samples of 64 alveoli of first molar roots in macerated swine maxillas prepared with perchloric acid to simulate periapical lesions. The specimens were evaluated using CBCT (55-mm high and 100-mm diameter cylinder at 0.2-mm voxel resolution) for the presence of oroantral communication (OAC) caused by the simulated lesions. Sensitivity, specificity, and accuracy were calculated. Fair values were obtained for accuracy (66%-78%) and good values for specificity (70%-98%), whereas the values for sensibility showed relevant variation (41%-78%). For this reason, the interobserver agreement score was weak. CBCT proved capable of evaluating the integrity of the cortical sinus (absence of oroantral communication) when it lies close to an apical periodontitis lesion. However, the low interobserver agreement reflects the difficulty in performing diagnoses when OAC is adjacent to a periapical lesion, using the acquisition protocol adopted in this research. This could be attributed to the high level of image noise.

Influence of cone-beam computed tomographic scan mode for detection of horizontal root fracture.

INTRODUCTION: The purpose of the present study was (1) to test the accuracy of a small-volume cone-beam computed tomographic (CBCT) device in detecting horizontal root fractures (HRFs) in teeth with and without an intracanal metallic post (IMP) and (2) to investigate the use of 2 different acquisition protocols of a CBCT device for HRF diagnosis. METHODS: Forty endodontically treated teeth with and without an IMP were examined using PreXion 3D CBCT scanner (Terarecon, San Mateo, CA) with a 5-cm high and 5-cm diameter cylinder at 0.10-mm voxel reconstruction. Two observers analyzed the samples to determine the presence and location of HRFs. RESULTS: Sensitivity values ranged from 0.40-0.80. The most favorable results were found for the samples with no IMP observed using the protocol of a higher number of x-ray projections (0.70-0.80). Accuracy in the groups with an IMP ranged from 75%-90% in the 1024 x-ray projection protocol (HI-HI group) versus 70%-85% for the same samples examined in the 512 x-ray projection protocol (HI-STD group). Intraobserver agreement ranged from relevant to perfect concordance for both protocols (HI-HI = Kappa: 0.60-1.00 and HI-STD = Kappa: 0.55-0.89). Interobserver agreement ranged from moderate to perfect concordance for both protocols (HI-HI = Kappa: 0.79-0.89 and HI-STD = Kappa: 0.42-0.76). CONCLUSIONS: Even though there are statistically significant differences for the protocol with the higher number of x-ray projections, we found high accuracy, sensitivity, sensibility, and intra- and interobserver agreement in detecting HRFs for both Prexion 3D protocols.

Assessment of open source software for CBCT in detecting additional mental foramina

The purpose of this study was to evaluate which post-processing imaging protocol would be better to analyze the additional mental foramen (AMF) in preoperative planning with cone-beam computed tomography (CBCT) exams, and to test reproducibility of measurements, using open source software (OsiriX). The software was used to detect the cases of AMF from among 58 exams for dental implant planning in edentulous mandible areas-three cases were found. The case images were submitted to qualitative analysis using 2D orthogonal MPR, 3D-MPR and 3D volume rendering protocols by two oral and maxillofacial radiologists. Quantitative analysis used the 3D-MPR protocol; the closed polygon tool measured the mental foramen (MF) and the AMF areas; the length tool measured the distance between foramina. The measurements were performed independently by the examiners, at two different times. Intra- and interexaminer agreement was assessed using the intraclass correlation coefficient. The panoramic view did not show the MF and the AMF clearly. The AMF could be detected in the parasagittal view. 2D Orthogonal MPR was effective to observe the AMF in some cases. The 3D-MPR and 3D view protocols were the most effective to locate and analyze the AMF. In conclusion, a 3D view improves visualization when anatomical points are not clearly visible. 3D-MPR was considered a more effective post-processing imaging protocol to observe foramina relationships. The high reproducibility of measurements for anatomical MF variations was established using specific tools featured in open source software for CBCT. OsiriX is realistic and recommended for preoperative planning.

Assessment of open source software for CBCT in detecting additional mental foramina.

The purpose of this study was to evaluate which post-processing imaging protocol would be better to analyze the additional mental foramen (AMF) in preoperative planning with cone-beam computed tomography (CBCT) exams, and to test reproducibility of measurements, using open source software (OsiriX). The software was used to detect the cases of AMF from among 58 exams for dental implant planning in edentulous mandible areas-three cases were found. The case images were submitted to qualitative analysis using 2D orthogonal MPR, 3D-MPR and 3D volume rendering protocols by two oral and maxillofacial radiologists. Quantitative analysis used the 3D-MPR protocol; the closed polygon tool measured the mental foramen (MF) and the AMF areas; the length tool measured the distance between foramina. The measurements were performed independently by the examiners, at two different times. Intra- and interexaminer agreement was assessed using the intraclass correlation coefficient. The panoramic view did not show the MF and the AMF clearly. The AMF could be detected in the parasagittal view. 2D Orthogonal MPR was effective to observe the AMF in some cases. The 3D-MPR and 3D view protocols were the most effective to locate and analyze the AMF. In conclusion, a 3D view improves visualization when anatomical points are not clearly visible. 3D-MPR was considered a more effective post-processing imaging protocol to observe foramina relationships. The high reproducibility of measurements for anatomical MF variations was established using specific tools featured in open source software for CBCT. OsiriX is realistic and recommended for preoperative planning.

Detection of simulated incipient furcation involvement by CBCT: an in vitro study using pig mandibles

The aim of the present study was to test the reproducibility, sensitivity, and specificity of cone-beam computed tomography (CBCT) in detecting incipient furcation involvement. Fifteen macerated pig mandibles, with intact second molar teeth and preserved adjacent cortical areas, were used. Simulated lesions were created in the furcation region of these teeth by applying 70% perchloric acid in up to four possible buccal/lingual sites in the right/left sides of each mandible. The mandibles were then submitted to a CBCT scan. Two blinded and calibrated experienced oral and maxillofacial radiologists interpreted the exams. Furcation involvement was also assessed in the regions without simulated lesions. CBCT showed high levels of accuracy, ranging from 78% to 88%. The variations in Kappa values for intra- and inter-observer agreement (0.41-0.59) were considered moderate. CBCT can be considered a reliable and accurate method for detecting incipient furcation involvement.

Detection of simulated incipient furcation involvement by CBCT: an in vitro study using pig mandibles.

The aim of the present study was to test the reproducibility, sensitivity, and specificity of cone-beam computed tomography (CBCT) in detecting incipient furcation involvement. Fifteen macerated pig mandibles, with intact second molar teeth and preserved adjacent cortical areas, were used. Simulated lesions were created in the furcation region of these teeth by applying 70% perchloric acid in up to four possible buccal/lingual sites in the right/left sides of each mandible. The mandibles were then submitted to a CBCT scan. Two blinded and calibrated experienced oral and maxillofacial radiologists interpreted the exams. Furcation involvement was also assessed in the regions without simulated lesions. CBCT showed high levels of accuracy, ranging from 78% to 88%. The variations in Kappa values for intra- and inter-observer agreement (0.41-0.59) were considered moderate. CBCT can be considered a reliable and accurate method for detecting incipient furcation involvement.

Use of large-volume cone-beam computed tomography in identification and localization of horizontal root fracture in the presence and absence of intracanal metallic post.

INTRODUCTION: The objective of the study was to evaluate the ability of large-volume cone-beam computed tomography (CBCT) to detect horizontal root fracture and to test the influence of a metallic post. METHODS: Through the examination of 40 teeth by large-volume CBCT (20-cm height and 15-cm diameter cylinder) at 0.2-mm voxel resolution, 2 observers analyzed the samples for the presence and localization of horizontal root fracture. RESULTS: The values of accuracy in the groups that had no metallic post ranged from 33%-68%, whereas for the samples with the metallic post, values showed a wide variation (38%-83%). Intraobserver agreement showed no statistically significant difference between the groups with/without metallic post; both ranged from very weak to weak (kappa, 0.09-0.369). CONCLUSIONS: The low accuracy and low intraobserver and interobserver agreement reflect the difficulty in performing an adequate diagnosis of horizontal root fractures through a large-volume CBCT by using a small voxel reconstruction.

Detection of horizontal root fracture with small-volume cone-beam computed tomography in the presence and absence of intracanal metallic post.

INTRODUCTION: The aim of the present study was to test the accuracy of small-volume cone-beam computed tomography (CBCT) scanning in the detection of horizontal root fractures and to assess the influence of a metallic post. METHODS: Forty teeth were divided into four groups based on the presence of metallic posts and horizontal root fracture. The teeth were examined by small-volume CBCT scanning at 0.2-mm voxel resolution. Three observers analyzed the samples for the presence of a horizontal root fracture. Sensitivity and specificity were calculated. RESULTS: High values for accuracy (73%-88%) were obtained in the groups without a metallic post, and statistically significant differences were found when the group with a metallic post has been observed (55%-70%). Intraobserver agreement also showed statistically significant differences in the groups with a metallic post. CONCLUSIONS: Small-volume CBCT scanning showed high accuracy in detecting horizontal root fracture without a metallic post. However, the presence of a metallic post significantly reduced the specificity and sensitivity of this examination.

Tomografia computadorizada por feixe cônico para detecção de lesões incipientes de furca simuladas em mandíbulas suínas maceradas / Cone beam computed tomography for detection of incipient furcation invasion in pig mandibles

As radiografias intraorais ilustram bem os estágios de reabsorção periodontal nas regiões interproximais. Entretanto, a sobreposição de estruturas dificulta avaliação da perda óssea nas corticais vestibular e lingual. A tomografia computadorizada por feixe cônico (TCFC) é de elevada importância em várias especialidades odontológicas, tais como implantodontia, avaliação de lesões ósseas, estudo da articulação têmporo-mandibular e cirurgia buco-maxilo-facial. A TCFC também tem tido crescente indicação em outras áreas, como a periodontia e endodontia. O objetivo no presente estudo foi a) estabelecer o protocolo de aquisição mais adequado para a detecção de lesões incipientes de furca simuladas quimicamente; e b) avaliar a reprodutibilidade, sensibilidade e especificidade da TCFC, para a finalidade previamente citada. No presente estudo, foram utilizadas 15 mandíbulas suínas maceradas, que apresentavam o segundo molar íntegro e as corticais adjacentes preservadas As simulações de lesões em região de furca foram feitas com aplicação de ácido perclórico a 70%, em até quatro sítios possíveis em cada mandíbula (vestibular do lado direito, lingual do lado direito, vestibular do lado esquerdo, lingual do lado esquerdo) por um examinador participante que não avaliou as imagens. Nos 60 sitios possíveis, foram escolhidos aleatoriamente 20 para as simulações das lesões. Posteriormente, as mandíbulas foram submetidas à TCFC (i-CAT Next Generation) em dois. protocolos de aquição: voxel 0,2 mm e 0,25 mm, ambos com FOV de 6 cm de altura por 16 cm de diâmetro e com 26,9 segundos de tempo.

Dois observadores (radiologistas previamente calibrados) avaliaram os exames duas vezes, em ordem aleatória, sob iluminação controlada. Os observadores foram orientados a direcionar a avaliação das regiões dos segundos molares, e questionados se havia lesão ou não nos sítios avaliados. A interpretação das imagens foi realizada em uma estação de trabalho independente localizada no Laboratório de Imagem em Terceira Dimensão da Faculdade de Odontologia da Universidade de São Paulo, utilizando o software Xoran (Xoran Technologies). A sensibilidade, especificidade e reprodutibilidade da TCFC foram avaliadas nos dois protocolos. A TCFC apresentou especificidade alta, sensibilidade baixa e reprodutibilidade moderada na detecção de lesões incipientes de furca. A influência do tamanho do voxel não foi estatisticamente significativa na detecção destas lesões.

Intraoral radiographs illustrate the stages of resorption in periodontal interproximal regions. However, overlapping structures hinders evaluation of bone loss in the buccal and lingual cortical plates. The cone beam computed tomography (CBCT) is of high importance in various dental specialties such as implantology, evaluation of bone lesions, the study of temporomandibular joint and maxillo-facial surgery. The CBCT has also been increasing indications in other areas, such as periodontics and endodontics. The aim of this study was to establish a) the acquisition protocol most suitable for the detection of incipient furcation invasion chemically simulated and b) assess the reproducibility, sensitivity and specificity of CBCT for the purpose previously mentioned. In this study, 15 pigs macerated mandibles were used, which showed the second molar and the adjacent cortical integrity preserved. Simulated lesions in the furcation area were made with application of 70% perchloric acid, up to four possible sites in each jaw (the right buccal, the right lingual, the left buccal, and left lingual side) by an examiner participant who did not evaluate the images. In the 60 possible sites, 20 were randomly chosen for the simulated lesions. Subsequently, the mandibles underwent cone beam computed tomography (Next Generation i-CAT) in two acquisition protocols: at 0.2 mm and 0.25 mm voxel, both with FOV of 6 cm height by 16 cm in diameter and 26.9 seconds of time.

Two observers (calibrated radiologists) evaluated the examinations twice, in random order under controlled lighting. Observers were instructed to direct the evaluation to the regions of the second molars, and they were asked if there were or not injuries on those avaluated sites. Image interpretation was performed on an independent workstation located at the Third Dimension Laboratory of Image in the School of Dentistry, University of São Paulo, using the software Xoran (Xoran Technologies). The sensitivity, specificity and reproducibility of CBCT were assessed in both trials. The CBCT showed high specificity, low sensitivity and moderate reproducibility in the detection of incipient lesions, furcation. The influence of voxel size was not statistically significant in detecting these lesions.

Avaliação do grau de paralelismo no preparo de dentes suportes obtido por três técnicas / Evaluation of parallelism degree in the tooth support preparation using three different techniques

A proposta deste estudo foi avaliar a influência de três técnicas de transferência de planos guia para boca, a influência da experiência do operador, da região (anterior e posterior), da arcada (inferior e superior) e a interação destas quanto ao preparo de planos de guia confeccionados nas faces proximais de dentes suportes para prótese parcial removível. Foram instruídos 10 operadores (cirurgiões dentistas), 5 com mais de 5 anos de experiência e 5 alunos do último ano de graduação da Faculdade de Odontologia de São José dos Campos, Universidade Estadual Paulista "Julio de Mesquita Filho". Cada operador utilizou três técnicas que foram: método à mão livre, método com pino guia e método com delineador intrabucal (ParalAB), em manequins simulando classe três de Kennedy. A análise estatística ANOVA e o teste de Tukey foram os métodos utilizados para a interpretação dos resultados. Concluiu-se que a técnica que empregou o delineador intrabucal ParalAB obteve melhor paralelismo, seguido pela técnica com Pino Guia e pela técnica à Mão Livre. De acordo com a metodologia aplicada, foi possível concluir que a técnica empregada na realização dos preparos de planos de guia para a boca influencia na inclinação das superfícies produzidas, e que a experiência do operador interfere no grau de paralelismo executado por qualquer técnica, exceto os resultados obtidos pela técnica com ParalAB que usou um delineador intrabucal. A arcada superior e a região anterior tiveram melhores resultados em ambos os operadores.