i
THIAGO FARIAS ROCHA LIMA
AVALIAÇÃO DA TOMOGRAFIA COMPUTADORIZADA
DE FEIXE CÔNICO E DA RADIOGRAFIA PERIAPICAL NO
DIAGNÓSTICO DE REABSORÇÕES RADICULARES EM
DENTES TRAUMATIZADOS
EVALUATION OF CONE BEAM COMPUTED
TOMOGRAPHY AND PERIAPICAL RADIOGRAPHY IN
THE DIAGNOSIS OF ROOT RESORPTION IN
TRAUMATIZED TEETH
Piracicaba 2015
iii
UNIVERSIDADE ESTADUAL DE CAMPINAS FACULDADE DE ODONTOLOGIA DE PIRACICABA
THIAGO FARIAS ROCHA LIMA
AVALIAÇÃO DA TOMOGRAFIA COMPUTADORIZADA DE FEIXE CÔNICO E DA RADIOGRAFIA PERIAPICAL NO DIAGNÓSTICO DE REABSORÇÕES
RADICULARES EM DENTES TRAUMATIZADOS
EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY AND PERIAPICAL RADIOGRAPHY IN THE DIAGNOSIS OF ROOT RESORPTION IN TRAUMATIZED
TEETH
Orientadora: Adriana de Jesus Soares
Piracicaba 2015
Tese apresentada à Faculdade de Odontologia de Piracicaba da Universidade Estadual de Campinas como parte dos requisitos exigidos para obtenção do título de Doutor em Clínica Odontológica, na Àrea de Endodontia.
Thesis presents to the Piracicaba Dental School of the University of Campinas in partial fulfillment of the requirements for the degree of Doctor in Clinical Dentistry, in Endodontics area.
Este exemplar corresponde a versão final da tese defendida por Thiago Farias Rocha Lima e orientada pela Profa. Dra. Adriana de Jesus Soares.
_________________________ Assinatura da orientadora
iv
Fica catalográfica
Universidade Estadual de Campinas Biblioteca da Faculdade de Odontologia de Piracicaba
Marilene Girello - CRB 8/6159 Lima, Thiago Farias Rocha, 1985-
L628a Avaliação da tomografia computadorizada de feixe cônico e da radiografia periapical no diagnóstico de reabsorções radiculares em dentes traumatizados / Thiago Farias Rocha Lima. – Piracicaba, SP : [s.n.], 2015.
Orientador: Adriana de Jesus Soares.
Tese (doutorado) – Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba.
1. Endodontia. 2. Reabsorção da raiz (dentes). 3. Tomografia computadorizada de feixe cônico. I. Soares, Adriana de Jesus,1970-. II. Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. III. Título.
Informações para Biblioteca Digital
Título em outro idioma: Evaluation of cone beam computed tomography and
periapical radiography in the diagnosis of root resorption in traumatized teeth
Palavras-chave em inglês:
Endodontics Root resorption
Cone-beam computed tomography
Área de concentração: Endodontia Titulação: Doutor em Clínica
Odontológica Banca examinadora: Adriana de Jesus Soares [Orientador] Juan Ramon Salazar
Silva Ericka Tavares Pinheiro Alexandre Augusto Zaia
Francisco Haiter Neto
Data de defesa: 02-02-2015
vii RESUMO
O presente trabalho teve como objetivos: avaliar a acurácia da Tomografia Computadorizada de Feixe Cônico e de radiografias periapicais digitais no diagnóstico de reabsorções radiculares em dentes traumatizados e verificar a influência da presença do material obturador na detecção dessas lesões (capítulo 1); relatar dois casos clínicos de reabsorções radiculares cujo diagnóstico foi realizado por meio da Tomografia Computadorizada de Feixe Cônico (capítulo 2). No capítulo 1, a amostra desta pesquisa foi constituída por radiografias e tomografias de pacientes com reabsorções radiculares e histórico de trauma dental, coletadas do banco de dados de uma clínica radiológica. Vinte oito dentes com reabsorções inflamatórias externas (14 com tratamento endodôntico e 14 sem tratamento endodôntico), 8 dentes com reabsorções inflamatórias internas e 4 dentes com reabsorção por substituição foram incluídos. Vinte casos sem reabsorção foram selecionados para o grupo controle. A análise das imagens foi realizada por 2 endodontistas e 2 radiologistas, previamente calibrados. Os resultados revelaram que a sensibilidade, especificidade e acurácia da Tomografia Computadorizada de Feixe Cônico foi superior às radiografias periapicais para o diagnóstico de reabsorções inflamatórias externas e internas (p<0.05 / Teste t). Para reabsorção por substituição, não houve diferença entre os métodos avaliados (p>0.05 / Teste t). Nos dentes tratados endodonticamente, a tomografia também apresentou resultados estatisticamente superiores para o diagnóstico das reabsorções inflamatórias externas (p=0.0138 / Teste t). No capítulo 2, dois casos clínicos de reabsorções radiculares (1 de reabsorção cervical externa e 1 de reabsorção inflamatória interna) foram descritos. A abordagem terapêutica adotada durante o diagnóstico e tratamento foi minuciosamente detalhada. O tratamento da reabsorção cervical externa foi multidisciplinar e envolveu a endodontia e periodontia. No caso com reabsorção interna, apenas o tratamento endodôntico foi necessário. Após o período de proservação, ambos os casos apresentaram-se sem sintomatologia e o sucesso clínico foi verificado. Concluiu-se que a Tomografia Computadorizada de Feixe Cônico foi superior às radiografias periapicais em relação ao diagnóstico de reabsorções inflamatórias (capítulo 1) e apresenta-se como um importante
viii
recurso de diagnóstico auxiliar para a detecção, localização e planejamento do tratamento clínico das reabsorções radiculares (capítulo 2).
Palavras-chave: Endodontia. Tomografia computadorizada de feixe cônico. Reabsorção radicular.
ix ABSTRACT
The aims of this study were: to evaluate the accuracy of cone beam computed tomography (CBCT) and digital periapical radiography in diagnosing root resorption following dental trauma and to verify the influence of filling material in detecting these lesions. (Chapter 1); describe two cases reports of root resorptions diagnosed by CBCT (Chapter 2). In chapter 1, periapical radiographs and CBCT images of patients with root resorption and a history of dental trauma from the database of a private radiology clinic were retrospectively reviewed. The sample comprised 28 teeth with external inflammatory resorption (14 with and 14 without endodontic treatment), 8 teeth with internal inflammatory resorption, 4 teeth with replacement resorption and 20 normal teeth as the control group. Images were analyzed by two radiologists and two endodontists who were previously calibrated. The results showed that the sensitivity, specificity and accuracy of CBCT in diagnosing internal and external inflammatory resorption was significantly higher than for radiography (p < 0.05 / t test). For replacement resorption, no statistical difference was noted (p > 0.05 / t test). In endodontically treated teeth, CBCT was also statistically superior in diagnosing external inflammatory resorption (p = 0.0138 / t test). In chapter 2, two cases reports of root resorptions (cervical external resorption and internal inflammatory resorption) were described. The therapeutic approach adopted for the diagnosis and treatment was detailed. Treatment of cervical external resorption involved endodontics and periodontics.In casewith inflammatory internal resorption, only endodontic treatment wasnecessary.After the observation period, both cases were presented without symptoms and clinical success was confirmed. Based on these findings, it was concluded that CBCT was superior to periapical radiography in diagnosing inflammatory root resorption following dental trauma, with or without endodontic treatment (Chapter 1) and presents itself as an important resource of as an auxiliary diagnosis for the detection, location and planning of the clinical treatment of root resorption (Chapter 2).
xi SUMÁRIO DEDICATÓRIA XIII AGRADECIMENTOS XV INTRODUÇÃO 1 CAPÍTULO 1 - EVALUATION OF CONE BEAM COMPUTED
TOMOGRAPHY AND DIGITAL PERIAPICAL RADIOGRAPHY IN THE DIAGNOSIS OF ROOT RESORPTION IN TRAUMATIZED TEETH
4
CAPÍTULO 2 - DIAGNOSIS AND MANAGEMENT OF ROOT RESORPTION IN TRAUMATIZED TEETH USING CONE BEAM COMPUTED TOMOGRAPHY: REPORT OF TWO CASES
23
CONSIDERAÇÕES GERAIS 41
JUSTIFICATIVA DA PESQUISA 41
CONSIDERAÇÕES CLÍNICAS SOBRE AS REABSORÇÕES
RADICULARES 42
APLICAÇÕES DA TOMOGRAFIA COMPUTADORIZADA DE
FEIXE CÔNICO NA ENDODONTIA 48
CONCLUSÃO 54
REFERÊNCIAS 55
APÊNDICE 65
xiii
D
EDICATÓRIA Ao meu pai, Gilberto Rocha Lima, que sempre foi meu grande incentivador. Dedico esta tese ao senhor, que sempre me aconselhou e nunca mediu esforços para me ajudar. Agradeço pelo amor incondicional, amizade e companheirismo. Você é o meuexemplo de pai, marido e filho! Te amo muito!
À minha mãe, Maria Julita Farias Lima, por todo amor e carinho. Agradeço por ter me ensinado o valor do estudo desde a minha infância, a lutar pelos meus objetivos e nunca desistir. Você é um exemplo de dedicação e esforço! Te amo demais!
À minha esposa, Rafaela Ávila, pela linda família que estamos construindo. Obrigado pelo amor, paciência, compreensão e por meu ajudar a alcançar meus objetivos. Essa vitória também é sua! Te amo para sempre!
xv
A
GRADECIMENTOSA Deus...
Pelos meus pais, minha esposa e por cada dia me conceder uma experiência nova em sua presença. A conclusão desta tese é fruto de orações respondidas. Obrigado pela direção nos momentos de incerteza, por sempre guiar meus passos e perdoar minhas falhas. Louvo a Deus porque seus planos tem se cumprido na minha vida! Ebénezer: até aqui nos
ajudou o Senhor!
À minha orientadora Adriana de Jesus Soares...
Por ter me aceitado como aluno de mestrado e doutorado nesta instituição e por ter idealizado e me orientado neste trabalho. Agradeço por cada momento vivido na pós-graduação, pelos ensinamentos, correções e por ter sido minha mentora na carreira docente. Cada conquista profissional minha, será sua também! Onde eu estiver, sempre lembrarei que a primeira pessoa a estender sua mão e acreditar que eu pudesse me tornar um professor foi a senhora, que tornou-se minha mãe científica. Meu desejo é que possamos cultivar essa parceria e amizade por muitos anos! Tenho um carinho enorme pela senhora! Obrigado por
tudo, professora!
Aos colegas da pós-graduação...
Aos queridos, Juliana Nagata, Tiago Rosa, Fernanda Lins, Tereza Pedroza e Thaís Mageste que se tornaram grandes amigos durante esse período de pós-graduação.
xvi
Aprendi e me desenvolvi como docente observando a dedicação e competência de cada um de vocês. Essa amizade e parceria quero levar para sempre!
Às amigas do Serviço de Traumatismos Dentários da Faculdade de Odontologia de Piracicaba, Andrea Cardoso Pereira e Ana Carolina Correa Laurindo de Cerqueira Neto, que sempre me ajudaram em tudo que precisei. Obrigado pelo companheirismo durante esses anos e pela boa convivência que tivemos.
Ao amigo Thiago Gamba, que me ajudou a conduzir este trabalho e auxiliou na execução da análise estatística. Obrigado pela disponibilidade e por esclarecer todas as minhas dúvidas.
Aos demais amigos do laboratório de Endodontia da FOP/UNICAMP, Cimara
Barroso, Felipe Anacleto, Marlos Ribeiro, Aline Cristine Gomes, Ana Pimentel, Claudia Suzuki, Carlos Augusto Pantoja, Emmanuel Nogueira, Maria Raquel Monteiro, Erica Clavijo, Ariane Marinho, Daniela Miyagaki, Carolina Santos, Letícia Nobrega, Daniel Herrera e Maíra do Prado pelo convívio durante esse período.
Aos mestres...
Ao professor Francisco José de Souza Filho, que foi meu orientador durante a especialização em endodontia, pelos ensinamentos. Seu amor pelo ensino, sua experiência clínica e humildade servem de exemplo aos que, assim como eu, estão começando na carreira docente. Muito Obrigado!
Ao professor Alexandre Augusto Zaia, que sempre foi muito prestativo e atencioso. Obrigado pelos ensinamentos compartilhados. O senhor também é uma referência
profissional para mim!
Aos professores Caio Cezar Randi Ferraz, Débora Queiroz de Freitas e Fernanda Signoretti pelo zelo que tiveram em corrigir minha tese e pelas considerações realizadas no exame de qualificação.
xvii
Aos demais professores da área de endodontia da FOP-UNICAMP, José Flávio Affonso de Almeida e Brenda Paula Figueiredo de Almeida Gomes por todo conhecimento adquirido.
Á Faculdade de Odontologia de Piracicaba...
À Faculdade de Odontologia de Piracicaba da Universidade de Campinas, na pessoa de seu diretor, Prof. Dr. Guilherme Elias Pessanha Henriques.
À Coordenadoria Geral da Pós-Graduação da FOP/UNICAMP, em nome da Prof. Dra. Cínthia Pereira Machado Tabchoury e da secretária Érica Alessandra Pinho Sinhoreti, por toda atenção dispensada.
À Coordenadora de Pós-Graduação em Clínica Odontológica da FOP/UNICAMP, Profa. Dra. Karina Gonzales Silvério Ruiz.
Às funcionárias Ana Cristina Godoy e Helídia Maria, da Área de Endodontia, pela prontidão em sempre ajudar e solucionar dificuldades.
Às turmas de graduação, por me permitirem exercitar o aprendizado, e, dessa forma, capacitar ainda mais o meu exercício de cirurgião dentista!
1 INTRODUÇÃO
As sequelas clínicas e radiográficas de dentes acometidos por lesões traumáticas têm sido alvo de pesquisas em vários países (Soares et al., 2008; Eyoboglu et al., 2009; Hecova et al. 2010; Lauridsen et al, 2012). O tipo de trauma e o grau de rizogênese do dente traumatizado são os principais fatores relacionados ao desenvolvimento de algum tipo de complicação. Entre as injúrias traumáticas, as luxações e as avulsões são consideradas as mais severas, pois, nesses tipos de trauma, ocorre o deslocamento do dente no interior do alvéolo, o que pode provocar o rompimento do feixe vásculo-nervoso e a destruição de células que revestem a superfície radicular. Nessas situações, a necrose pulpar e reabsorções radiculares podem ocorrer (Neto et al., 2009; Lauridsen et al. 2012; Consolaro, 2012).
A reabsorção radicular ocorre como resultado da ação de células clásticas na superfície dentária. Esse processo pode ser fisiológico, como acontece durante a rizólise do dente decíduo, ou patológico (Liang et al. 2003; Patel et al., 2009; Patel et al., 2010). A movimentação ortodôntica, os traumatismos dentários e a presença de lesões periapicais são os principais fatores etiológicos da reabsorção patológica. A literatura apresenta uma variedade de classificações para as reabsorções radiculares, levando em consideração a superfície afetada (interna, externa e interna/externa), a fase de evolução do processo (ativa, paralisada e reparada), a região dentária afetada (coronária, cervical, radicular lateral e apical); a extensão do comprometimento causado pela lesão (simples e múltipla), a causa do processo (local, sistêmica e idiopática) e o mecanismo do processo (superficial, por substituição e inflamatória). O conhecimento dos diferentes tipos de reabsorção e o seu diagnóstico precoce são fundamentais para a determinação do plano de tratamento (Fuss et al., 2003; Consolaro, 2012).
Dentre os tipos de reabsorções, as inflamatórias externas e internas são as mais comumente diagnosticadas. As reabsorções externas podem promover a destruição do cemento e da dentina no terço cervical, médio e apical da raiz (Estrela et al., 2009; Patel et al. 2009). As internas provocam a destruição das paredes do canal radicular (Patel et al.,
2
2010; Nilsson et al., 2013). Se nenhuma intervenção for realizada, a progressão dessas lesões pode ocasionar a perda do elemento dental.
A reabsorção por substituição, frequentemente verificada após intrusões severas e reimplantes dentários, desenvolve-se quando células clásticas, provenientes do osso alveolar, começam a atuar sobre a raiz dentária, que começa a ser substituída gradativamente por tecido ósseo. (Finukani e Kirinons, 2003; Consolaro, 2012; Bastos et al., 2014).
O diagnóstico das reabsorções radiculares está condicionado a um exame clínico e radiográfico minucioso. Geralmente, as radiografias periapicais são as mais utilizadas para detecção das reabsorções, entretanto, elas não oferecem uma visão tridimensional da superfície reabsorvida e não permitem a determinação da verdadeira natureza e extensão da reabsorção (Andreasen et al. 1987; Goldberg et al., 1998; Patel et al., 2007; Liang et al., 2011) Além disso, nas superfícies vestibular e lingual, não é possível verificar a ocorrência dessas lesões (Coton et al., 2007).
A Tomografia Computadorizada de Feixe Cônico é um método radiográfico que tem sido utilizado em diversas áreas da Odontologia porque permite a análise tridimensional de estruturas dentárias, com alto contraste. Segundo a Associação Americana de Endodontia (2014), essa ferramenta pode ser utilizada para a detecção de reabsorções radiculares. Além de favorecer o diagnóstico, a imagem tomográfica permite que o examinador identifique a verdadeira natureza da reabsorção, contribuindo para definição do plano de tratamento. A localização da reabsorção, sua relação com o canal radicular e a extensão dessa lesão são fatores que estão relacionados diretamente a restaurabilidade do dente e podem interferir no prognóstico (Cohenca et al. 2007, Patel et al., 2007; Venskutonis et al., 2014). Entretanto, deve-se salientar que, quando comparada às radiografias periapicais, a Tomografia computadorizada de Feixe Cônico apresenta como desvatagem a alta dose de radiação e, portanto, sua indicação na endodontia deve ser criteriosamente analisada (Venskutonis et al., 2014).
Várias marcas de tomógrafos estão presentes no mercado. Esses sistemas diferenciam-se uns dos outros pelo tipo do receptor e funções que cada aparelho oferece.
3
Sabe-se que o tamanho do FOV e do VOXEL interfere na qualidade da imagem obtida (Spin-Neto et al., 2013; Da Silveira et al., 2014). Tomógrafos que apresentam a opção de voxel de tamanho reduzido são mais indicados em endodontia, pois a imagem obtida é mais nítida e permite que o observador visualize detalhes do canal radicular (Kamboroglu e Kursun, 2010). Contudo, o voxel reduzido apresenta uma desvantagem clínica. Há uma correlação positiva entre o tamanho do voxel e a dose de radiação, sendo que quanto menor, maior a exposição (Spin-Neto et al., 2013).
Apesar de favorecer o planejamento terapêutico de complicações endodônticas, a tomografia computadorizada também apresenta limitações. Nos dentes com tratamento de canal realizado e com pinos metálicos, a visualização de fraturas radiculares e perfurações torna-se dificultada (Hassan et al. 2009; Khedmat et al 2012, Haghanifar et al., 2014). Materiais radiopacos no interior do canal promovem a formação de artefatos que podem diminuir a habilidade de diagnóstico (Neves et al., 2014).
Considerando que o trauma dental é um problema de saúde pública mundial e que as reabsorções radiculares configuram como uma das principais complicações pós-traumáticas, estudos que abordem este tema apresentam grande relevância clínica. O uso da tomografia computadorizada de feixe cônico na endodontia representou um avanço no que se refere ao diagnóstico de reabsorções radiculares e permitiu que vários estudos in vitro fossem realizados. Entretanto, há poucos trabalhos clínicos publicados que comparem a tomografia e radiografia periapical na detecção de reabsorções radiculares em dentes acometidos por traumatismos dentários (Estrela et al., 2009; Patel et al., 2009).
Diante do exposto, é objetivo neste estudo verificar, por meio de dois métodos de avaliação radiográfica - tomografia computadorizada de feixe cônico e radiografias periapicais digitais - a acurácia no diagnóstico de reabsorções radiculares em dentes traumatizados e analisar a influência do material obturador na dectecção dessas lesões
4
CAPÍTULO 1 – EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY AND DIGITAL PERIAPICAL RADIOGRAPHY IN THE DIAGNOSIS OF ROOT RESORPTION IN TRAUMATIZED TEETH
*Este artigo está nas normas da revista Dental Traumatology
ABSTRACT
Background/Aim: Cone beam computed tomography (CBCT) is now an important technique
for evaluating endodontic complications such as fractures, perforations, and root resorption. This study aimed to evaluate the accuracy of CBCT and digital periapical radiography in diagnosing root resorption after dental trauma and verify the influence of filling material in detecting these lesions. Materials and Methods: The radiographs and CBCT images of patients with root resorption and a history of dental trauma from a private radiology clinic were reviewed retrospectively. The sample comprised 28 teeth with external inflammatory resorption (14 with and 14 without endodontic treatment), 8 teeth with internal inflammatory resorption, 4 teeth with replacement resorption, and 20 normal teeth as controls. Images were analyzed by two radiologists and two endodontists who were previously calibrated. The sensitivity, specificity, accuracy, and positive and negative predictive values were determined and the areas under the receiver operating characteristic curves (ROC) were calculated. The kappa coefficient assessed interobserver agreement and the t test determined significant differences between the imaging methods. Results: The accuracy of CBCT in diagnosing external (P=0.0144) and internal (P=0.0038) inflammatory resorption was significantly higher than for radiography. For replacement resorption, no statistical difference was noted (P>0.05). The areas under the curves were also statistically higher for CBCT (P<0.05). In endodontically treated teeth, CBCT was statistically superior in diagnosing external inflammatory resorption (P=0.0138). Conclusions: CBCT was superior to periapical radiography in diagnosing external and internal inflammatory root resorption after dental trauma and can be considered in the differential diagnosis of resorptive lesions in teeth with endodontic treatment.
5 INTRODUCTION
The diagnosis and treatment of root resorption is challenging in clinical practice. Root resorption is caused by inflammation initiated after dental trauma, orthodontic movement, internal bleaching, periodontal treatment, and idiopathic events (1–5). Resorption may occur on the internal or external surface of the tooth, but differential diagnosis is difficult using conventional radiography. Because radiographs provide only a two-dimensional image, they are inaccurate for determining the nature and location of resorption (3, 6, 7).
Endodontics has become a modern specialty due to recent technological advances (8). New diagnostic techniques have emerged with the aim of assisting in endodontic therapeutic planning. Cone beam computed tomography (CBCT) generates images in the axial, coronal, and sagittal directions, allowing three-dimensional visualization of dental structures (6, 9, 10). In endodontics, CBCT has become an important technique for studying the internal anatomy of the canal, detecting periapical lesions and dental trauma, planning endodontic surgery, and evaluating endodontic complications such as fractures, perforations, and root resorption (11–14).
The image quality of CBCT depends on the field of view (FOV) and voxel size (15). Images with smaller voxels have better resolution and depict endodontic lesions more accurately. Da Silveira et al. (16) examined the influence of FOV and voxel size on the measurement of the volume of simulated internal root resorption lesions through CBCT and found that measurement of resorption was more efficient in images with smaller voxels.
However, even with high-resolution CBCT images of endodontically treated teeth, the radiographic diagnosis of complications is difficult. Several in vitro studies evaluating the efficacy of CBCT in diagnosing root fractures and tooth perforation after root canal treatment found that the sensitivity, specificity, and accuracy of CBCT was lower compared with those in images of untreated teeth (17–19). Few clinical studies have assessed the influence of endodontic treatment in the diagnosis of root resorption.
6
The aim of this study was to evaluate the accuracy of CBCT and digital periapical radiographs in diagnosing root resorption after traumatic dental injuries and to verify the influence of filling material when detecting these lesions.
MATERIALS AND METHODS
This research was approved by the Ethics Committee of Piracicaba Dental School, UNICAMP.
The periapical radiographs and CBCT images used in this study were obtained from the database at the Institute of Radiological and Orthodontic Documentation (Sao Paulo, Brazil) from July 2012 to July 2014. The initial selection criteria were as follows: patients older than 18 years presenting with a history of traumatic injuries in anterior teeth. A total of 817 images were first analyzed according to the presence of root resorption by two investigators (one endodontist and one radiologist). When there was consensus on the presence of resorption, the radiological report was checked to confirm the diagnosis. Sixty cases were selected as follows: 28 teeth with external inflammatory resorption (14 with endodontic treatment, and 14 without endodontic treatment) (Figure 1), 8 teeth with internal inflammatory resorption (Figure 2), 4 teeth with replacement resorption (Figure 3), and 20 teeth with no resorption.
Radiographic technique
Sixty periapical radiographs and 60 CBCT scans were analyzed. Radiography was performed using a dental X-ray machine (Focus, Kavo, Joinville, Santa Catarina, Brazil) with a digital CCD sensor unit and the following parameters: 70 kV, 7mA, and 0.2 s. All radiographs were performed using intraoral positioners and the paralleling technique. CBCT was performed using a Prexion 3D scanner (Terarecon, San Mateo, CA, USA) with a 5-cm high and 5-cm diameter cylinder at 0.10-mm voxel reconstruction.
7
Image analysis
The images were examined by two endodontists and two radiologists, each with more than 3 years of clinical experience. Before the analysis, the examiners were calibrated using radiographs and CBCT scans of confirmed cases of external inflammatory resorption, internal inflammatory resorption and replacement resorption. The kappa test yielded a value of >0.7.
Twenty days later, the images were evaluated individually and independently on a laptop (Toshiba Portege R500-11Z; Tokyo, Japan) with 1280 × 1224 pixel LCD resolution, under ambient conditions, and with optimal screen luminance. To avoid eyestrain, only 24 images were analyzed per day. Resorption was diagnosed on a five-point scale as follows: 1- definitely present; 2 - probably present; 3 - uncertain diagnosis; 4 - probably absent; and 5 - definitely absent. Fifteen days later, 25% of the sample was re-evaluated to calculate the intra-rater reproducibility.
The results were tabulated and analyzed using SPSS software (version 22.0: SPSS Inc., Chicago, IL, USA). The inter-rater and intra-rater assessment data were analyzed by kappa statistics for both the radiographs and the CBCT images. The sensitivity, specificity, accuracy, and the positive and negative predictive values were determined. In addition, the areas under the receiver operating characteristic curves (ROC) were calculated. The t test was used to detect any statistical difference between CBCT and periapical radiography in diagnosing each resorption type. The correlation between the presence of filling material and the detection of external inflammatory resorption was also examined. A
P value <0.05 was considered to indicate statistical significance in all tests.
RESULTS
The inter-rater kappa values for the radiographs and CBCT images are summarized in Table 1. The kappa value for intra-rater agreement was greater than 0.8 for all examiners.
8
Table 2 presents the sensitivity, specificity, positive predictive values, negative predictive values, and accuracy for CBCT and periapical radiography in diagnosing external, internal, and replacement resorption. Sensitivity, specificity, and the diagnostic accuracy of CBCT was statistically higher for external inflammatory resorption and internal inflammatory resorption (P<0.05). No statistical difference was noted for replacement resorption (P>0.05).
The ROC curves of the two imaging methods evaluated are shown in Figure 4. The values for the respective areas under the curves, standard errors, and significance levels are shown in Table 3. For external and internal inflammatory resorption, the areas under the curves were statistically higher for CBCT (P<0.05).
Table 4 summarizes the relationship between the presence of filling material and the detection of external inflammatory resorption. The diagnostic accuracy of CBCT was superior to that of radiography for teeth with endodontic treatment (P=0.0138). No statistical differences between periapical radiography and CBCT scans were observed in the teeth without endodontic treatment.
DISCUSSION
Root resorption is a frequent complication after dental trauma, especially when the trauma affects the supportive dental tissues. The prevalence of resorption after injury varies with the specific trauma. Several studies have reported that external inflammatory resorption occurs in 5–70% of cases of luxation and 20–50% of cases of avulsion. Replacement resorption is more frequent with intrusion procedures with a prevalence of 20– 40%, and in dental reimplantation, affecting 50–70% of cases (20–22). The cause of internal inflammatory resorption is unknown; however, some studies implicate dental trauma as one factor triggering resorption (4, 5, 23). In this study, only anterior teeth with a history of trauma were included because resorption is commonly diagnosed in cases of dental trauma. It was not possible to determine the specific trauma for each tooth evaluated as the sample was selected retrospectively from a clinical database of a private radiology clinic.
9
The images were analyzed by radiologists and endodontists because it is these clinicians who are most confronted with resorption in clinical practice. Other studies comparing CBCT and radiography for diagnosing endodontic disease also used experts in endodontics or radiology as examiners (24–28).
Resorption is generally detected using periapical radiography, and orthoradial, mesioradial, and distoradial radiographs all aid in the diagnosis. However, the two-dimensional nature of these images makes periapical radiography inaccurate for determining the location, severity, and type of resorption; this has been confirmed in several studies (6, 24, 29). In this study, only orthoradial radiographs were evaluated as these were the only radiographs included in the database.
Failure to diagnose resorption undermines treatment and worsens the prognosis, making CBCT an important resource for detecting resorption lesions. Tomography generates three-dimensional images and allows the clinician to observe resorption even at the early stages (30, 31). In this study, CBCT exhibited the highest sensitivity, specificity, and accuracy for external and internal inflammatory resorption compared with digital periapical radiography. The areas under the ROC curves confirm these results. Patel et al. (30) also conducted a clinical study to verify the efficacy of CBCT in diagnosing root resorption and found similar results. Another previous study assessing artificially prepared root resorption lesions using ROC analysis also observed that CBCT was superior to periapical radiography (32). The accuracy of radiography and CBCT was similar for replacement resorption. This similarity likely reflects the characteristic pathology of these lesions; in cases of replacement resorption, the root is completely replaced by bone tissue, which is easily discerned on periapical radiographs. Furthermore, few cases of replacement resorption were included in this study.
This study used the Prexion 3D CT scanner, which generates small voxel images (0.1 mm). Several studies have shown that the voxel size influences the image resolution and the diagnostic usefulness (2, 16, 28, 33). Spin-Neto et al. (15) reported that variation in the voxel size can interfere with the diagnosis of endodontic disease. Da Silveira et al. (16) investigated the influence of voxel size on the measurement of the volume of simulated
10
internal root resorption lesions through CBCT and found that measurement of resorption was best in images with smaller voxels. The favorable results for CBCT in the present study may also be related to the voxel size of the images.
The presence of gutta-percha and metal posts inside the root canal may make identification of root resorption difficult on radiographs, especially in lesions located at the labial, palatal, and lingual surfaces. On CBCT, metal posts and filling material generate artifacts and may decrease the diagnostic accuracy (27). This study compared the accuracy of CBCT and radiography in diagnosing external inflammatory resorption in teeth with and without root canal treatment, and found that CBCT was statistically superior (P=0.0138) to periapical radiographs in teeth with endodontic treatment. This type of analysis has not been reported previously, although in vitro studies have examined the effect of filling material on diagnostic accuracy for fractures and root perforations. The current results indicate that the accuracy of CBCT and radiographs was lower in endodontically treated teeth, although the results for CBCT were more favorable overall (17, 27, 34).
CBCT represents a breakthrough in medical imaging and, as a result, has been used in therapeutic planning for endodontic complications. However, CBCT should not be used routinely for diagnosing root resorption, but it is recommended when lesions are suspected on routine periapical radiographs. All exposure to ionizing radiation should follow the “as low as reasonably achievable” principle. For this reason, the selection criteria and the parameters for each CBCT scan protocol should be strict and follow the respective clinical indication. Root resorption is difficult to detect because these lesions are usually asymptomatic. Diagnosis is based primarily on radiographic methods; however, a proper clinical history and examination are essential to confirm the diagnosis.
11 CONCLUSION
CBCT was superior to periapical radiography in diagnosing inflammatory root resorption after dental trauma, especially in teeth with endodontic treatment, and should be considered in the differential diagnosis of resorptive lesions.
REFERENCES
1 - Heithersay GS. Clinical, radiologic and histopathologic features of invasive cervical resorption. Quintessence Int. 1999; 30: 27–37.
2 - Fuss Z, Tsesis I, Lin S. Root resorption: diagnosis, classification and treatment choices based on stimulation factors. Dent Traumatol 2003; 19: 175–82.
3 - Liang H, Burkes EJ, Frederiksen NL. Multiple idiopathic cervical root resorption: systematic review and report of four cases. Dent Radiol. 2003; 32: 150–5.
4 - Patel S, Kanagasingam S, Pitt Ford T. External cervical resorption: a review. J Endod. 2009; 35: 616-25.
5 - Patel S, Ricucci D, Durak C, Tay F. Internal root resorption: a review. J Endod. 2010; 36: 1107-21.
6 - Patel S, Dawood A, Ford TP, Whaites E. The potential applications of cone beam computed tomography in the management of endodontic problems. Int Endod J. 2007;10:818–30.
7 - Bhuva B, Barnes JJ, Patel S. The use of limited cone beam computed tomography in the diagnosis and management of a case of perforating internal root resorption. Int Endod J. 2011; 44: 777–86.
12
8 - Mortman RE. Technologic advances in endodontics. Dent Clin North Am. 2011; 55: 461-80.
9 - Patel S. New dimensions in endodontic imaging: part 2. Cone beam computed tomography. Int Endod J. 2009; 6: 463–75.
10 - Venskutonis T, Daugela, P, Strazdas M, Juodzbalys, G. Accuracy of Digital Radiography and Cone Beam Computed Tomography on Periapical Radiolucency Detection in Endodontically Treated Teeth. J Oral Maxillofac Res. 2014; 5: 1-7.
11 - Michetti J, Maret D, Mallet J-P, Diemer F. Validation of cone beam computed tomography as a tool to explore root canal anatomy. J Endod 2010; 7: 1187–90.
12 - Neelakantan P, Subbarao C, Subbarao CV. Comparative evaluation of modified canal staining and clearing technique, cone-beam computed tomography, peripheral quantitative computed tomography, spiral computed tomography, and plain and contrast medium-enhanced digital radiography in studying root canal morphology. J Endod. 2010; 9: 1547– 51.
13 - de Alencar AH, Dummer PM, Oliveira HC, et al. Procedural errors during root canal preparation using rotary NiTi instruments detected by periapical radiography and cone beam computed tomography. Braz Dent J. 2010; 6: 543–9.
14 - Shemesh H, Cristescu RC, Wesselink PR, Wu M-K. The use of cone-beam computed tomography and digital periapical radiographs to diagnose root perforations. J Endod. 2011; 4: 513-6.
15 - Spin-Neto R, Gotfredsen E, Wenzel A. Impact of voxel size variation on CBCT-based diagnostic outcome in dentistry: a systematic review. Journal of Digital Imaging. 2013; 26: 813-20.
16 - da Silveira PF, Fontana MP, Oliveira HW, Vizzotto MB, Montagner F, Silveira HL, Silveira HE. CBCT – based volume of simulated root resorption – influence of FOP and voxel size. Int Endod. 2014. doi: 10.1111/iej.12390.
13
17 - Hassan B, Metska ME, Ozok AR, van der Stel P, Wesselink, PR. Detection of vertical root fractures in endodontically treated teeth by a cone beam computed tomography scan. J Endod. 2009; 35: 719-22.
18 - Khedmat S, Rouhi N, Drage N, Shokouhinejad N, Nekoofar MH. Evaluation of three imaging techniques for detection of vertical root fractures in the absence and presence of gutta-percha root fillings. Int Endod J. 2012; 45: 1004-9.
19 - Haghanifar S, Moudi E, Mesgarani A, Bijani A, Abbaszadeh N. A comparative study of cone-beam computed tomography and digital periapical radiography in detecting mandibular molars root perforations. Imaging Science in Dentstry. 2014; 44: 115-9.
20 - Soares AJ, Gomes BPFA, Zaia AA, Ferraz CCR, Souza-Filho FJ. Relationship between clinical radiographic evaluation and outcome of teeth replantation. Dental Traumatol. 2008; 24: 183-188.
21 - Neto JJ, Gondim JO, de Carvalho FM, Giro EM. Longitudinal clinical and radiographic evaluation of severely intruded permanent incisors in a pediatric population. Dent Traumatol. 2009; 25: 510-4.
22 - Hecova H, Tzigkounakis V, Merglova V, Netolicky J. A retrospective study of 889 injured permanent teeth. Dent Traumatol. 2010; 26: 466-75.
23 - Gunraj MN. Dental root resorption Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999; 88:647-53.
24 - D’Addazio PSS, Campos CN, €Ozcan M, et al. A comparative study between conebeam computed tomography and periapical radiographs in the diagnosis of simulated endodontic complications. Int Endod J 2010; 3: 218–24.
25 - Özer SY. Detection of vertical root fractures by using cone beam computed tomography with variable voxel sizes in an in vitro model. J Endod. 2011; 37: 75-9.
26 - Bernardes RA, de Paulo RS, Pereira OP, Duarte MAH, Zapata RO, Azevedo JR. Comparative study of cone beam computed tomography and intraoral periapical radiographs
14
in diagnosis of lingual-simulated external root resorptions. Dent Traumatol 2012; 28: 268– 72.
27 - Neves FS, Freitas DQ, Campos PSF, Ekestubbe A, Lofthag-Hansen S. Evaluation of Cone-beam Computed Tomography in the Diagnosis of Vertical Root Fractures: The Influence of Imaging Modes and Root Canal Materials. J Endod. 2014; 40: 1530-36.
28 - Liedke GS, da Silveira HED, da Silveira HLD, Dutra V, Figueiredo JAP. Influence of Voxel Size in the Diagnostic Ability of Cone Beam Tomography to Evaluate Simulated External Root Resorption. J Endod. 2009; 35: 233-35.
29 - Liang Y-H, Li G, Wesselink PR, Wu M-K. Endodontic outcome predictors identified with periapical radiographs and cone-beam computed tomography scans. J Endod. 2011; 37: 326-31.
30 - Patel S, Wilson R, Dawood A, Focchi F, Mannocci F. The detection of periapical pathosis using digital periapical radiography and cone beam computed tomography - part 2: a 1-year post-treatment follow-up. Int Endod J. 2012; 45: 711-23.
31 - Patel S, Wilson R, Dawood A, Mannocci F. The detection of periapical pathosis using periapical radiography and cone beam computed tomography - part 1: pre-operative status. Int Endod J. 2012; 45: 702-10.
32 - Durack C, Patel S, Davies J, Wilson R, Mannocci F. Diagnostic accuracy of small volume cone beam computed tomography and intraoral periapical radiography for the detection of simulated external inflammatory root resorption. Int Endod J. 2011; 44: 136-47. 33 - Vizzotto MB, Silveira PF, Arús NA, Montagner F, Gomes BP, da Silveira HE. CBCT for the assessment of second mesiobuccal (MB2) canals in maxillary molar teeth: effect of voxel size and presence of root filling. Int Endod J. 2013; 46: 870-6.
34 - Venskutonis T, Plotino G, Juodzbalys G, Mickeviciené. The Importance of Cone beam Computed Tomography in the Management of Endodontic Problems: A Review of the Literature. J Endod. 2013; 40: 1895-901.
15 TABLES
Table 1: Kappa values for inter-examiner agreement. Examiner External inflammatory resorption Internal inflammatory resorption Replacement resorption Periapical Radiography Endodontists 0.871 0.795 1.0 Radiologists 0.824 0.805 1.0 CBTC Endodontists 0.781 0.795 1.0 Radiologists 1.0 1.0 1.0
Table 2: Sensitivity, specificity, PPV, NPV and accuracy for CBCT and periapical radiographs for detecting root resorption.
PPV, positive predictive value; NPV, negative predictive value. *t test
Sensitivity p Specificity p PPV P NPV p Accuracy p
External inflammatory resorption
Periapical Radiography 0.874 0.005 0.875 0.005 0.860 0.006 0.889 0.005 0.883 0.0144 CBTC 1.00 0.984 0.983 1.00 0.992
Internal inflammatory resorption
Periapical Radiography 0.563 0.005 0.961 <0.001 0.690 <0.001 0.935 <0.001 0.908 0.0038 CBTC 0.938 1.00 1.00 1.00 0.991 Replacement resorption Periapical Radiography 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 CBTC 1.00 1.00 1.00 1.00 1.00 1 6
Table 3: Values of the areas under the ROC curves for periapical radiography and CBCT.
Area Standart desviation Confidence interval
95% p value*
External Inflammatory resorption
Periapical Radiography 0.957
0.0102 0.0222 – 0.0621 < 0.001
CBCT 1.00
Internal Inflammatory resorption
Periapical Radiography 0.923 0.0172 0.0422 – 0.110 < 0.001 CBCT 0.999 Replacement resorption Periapical Radiography 1.00 0.00 0.00 1 CBCT 1.00 *t test 1 7
18
Table 4: Accuracy (standart desviation) of CBCT and periapical radiography for diagnosing external inflammatory root resorption in teeth with or without endodontic treatment.
Accuracy With endodontic treatment Without endodontic treatment p value* Periapical Radiographs 0.912 (0.026) 0.957 (0.027) 0.0611 CBCT 1.00 (0.00) 1.00 (0.00) 1.00 p value* 0.0138 0.07 - *t test
18
Figure 1: External inflammatory resorption: (a) Periapical radiography of maxillary left lateral incisor (without endodontic treatment); (b,c,d) CBCT reconstructed (coronal, axial and sagittal slice); (e) Periapical radiography of maxillary rigth central incisor (with endodontic treatment); (f,g,h) CBCT reconstructed (coronal, axial and sagittal slice).
FIGURES
1
19
Figure 2: Internal inflammatory resorption: (a) Periapical radiography of mandibular left lateral incisor (b, c, d) CBCT reconstructed (coronal, axial and sagittal slice).
2
20
Figura 3: Replacement resorption: (a) Periapical radiography of maxillary left central incisor (b, c, d) CBCT reconstructed (coronal, axial and sagittal slice).
2
21
Figura 4: ROC curves for periapical radiography and CBCT: (a) External inflammatory resorption (b) Internal Inflammatory resorption (c) Replacement resorption.
2
23
CAPÍTULO 2 – DIAGNOSIS AND MANAGEMENT OF ROOT RESORPTION IN TRAUMATIZED TEETH BY USING CONE BEAM COMPUTED TOMOGRAPHY: REPORT OF TWO CASES
*Este artigo está nas normas da revista Dental Traumatology
ABSTRACT
Root resorption leads to progressive loss of mineralized tooth tissue, and diagnosing these lesions is a challenge for the clinician. Currently, cone beam computed tomography (CBCT) is a radiographic adjunct used for the detection of resorptions, thereby enabling determination of the exact location and extent of the resorbed area. This report presents two cases of root resorption in which CBCT aided in determining the treatment plan when it was used as the diagnostic tool.
Key words: root resorption; cone beam computed tomography; endodontics.
INTRODUCTION
Root resorptions are lesions that lead to the loss of mineralized tooth tissue via physiological or pathological processes (1,2). Physiological resorption occurs in deciduous teeth during tooth exfoliation. In contrast, inflammatory processes cause pathological resorption. During resorption progression, the protective barriers, such as the cementum and cementoblasts on the root surface and pre-dentin and odontoblasts in the pulp cavity, are destroyed and clastic cells act on the exposed dental tissues (3,4).
24
Root resorption can be broadly classified into external or internal resorption based on the location of the resorption in relation to the root surface. Internal resorption is a progressive process initiated within the pulp space with loss of dentin (2). Although trauma and pulpal inflammation/infection are the major contributory factors in the initiation of internal resorption, all of the etiologic factors and the pathogenesis have not yet been completely elucidated (2).
External root resorption can be further classified into surface resorption, external inflammatory resorption, external replacement resorption, external cervical resorption, and transient apical breakdown. Cervical external resorption is defined as a localized resorptive process that commences on the surface of the root below the epithelial attachment and the coronal aspect of the supporting alveolar process, namely the zone of the connective tissue attachment (5,6). These lesions have a multifactorial etiology, but traumatic dental injuries are the main causative factors (5,6).
Diagnosis of root resorption is possible after a complete clinical and radiographic examination (7). Internal resorption is often seen on radiographs because of linear expansion of the canal with well-defined margins (2,8). In external resorption, the contour of the canal is discernible within the resorption lesion (7). However, periapical radiographs do not reveal the actual extent of these lesions (5).
Currently, cone beam computed tomography (CBCT) has proven to be an important diagnostic tool in endodontics (9-11). Several studies have demonstrated the effectiveness of CBCT in detecting endodontic problems such as root fractures, perforations, and resorptions (12-14). CBCT scans allow images to be viewed in the axial, coronal, and sagittal slices and are an important tool used for the diagnosis of root resorption. In addition, CBCT allows a detailed assessment of the resorbed area so that the exact location and extent can be determined, ensuring the establishment of a more effective treatment plan (5).
This article presents two cases reports of root resorption where CBCT has been used as an important diagnostic tool and has aided in deciding the appropriate treatment plan.
25 CASE REPORT 1
A 30year-old woman visited the Dental Trauma Service at the Piracicaba Dental School (UNICAMP) for evaluation of tooth 21. During the anamnesis, the patient reported a bicycle accident at 8 years of age that caused an enamel and dentin fracture in teeth 11, 12, and 21. Clinically, tooth 21 did not respond to pulp sensitivity testing (Endo-Frost, Roeko, Langenau, Germany), and the patient reported no pain on percussion and palpation. Radiographic examination showed a radiolucent area in the cervical region of tooth 21, thereby suggesting external cervical resorption. No periapical lesion was observed (Figure 1).
CBCT was performed (Galileos, Sirona Dental Systems Inc., Bensheim, Hessen, Germany) to determine the extent and depth of the lesion in the three spatial levels. Based on the CBCT images and three-dimensional reconstructions (Figure 2), a diagnosis of cervical external resorption of Heithersay class II was determined. The treatment plan consisted of endodontic treatment and surgical intervention for removal of the inflamed granulation tissue that occupied the lesion cavity and repair of the resorption defect with resin-modified glass ionomer cement.
After the patient was anesthetized, the crown was accessed followed by absolute isolation. The root canal was cleaned and shaped up to the size of the R40 (40.06) instrument of the RECIPROC system (VDW, Germany). Odontometry was performed by using an electronic apex locator (Novapex, Forum Technologies, Richion, Le-Zion, Israel). 2% Chlorhexidine gel (Endogel, Itapetininga, Brazil) was used as a chemical auxiliary substance, and the canal was irrigated with 5 mL of saline solution after every file change. All procedures were performed under the magnification of a surgical microscope. Subsequently, the canal was irrigated with 3 mL of 17% ethylenediaminetetraacetic acid (EDTA) and 5 mL of saline solution. After drying the canal with paper points, the root canal was filled with gutta-percha plasticized cones and AH Plus sealer (Dentsply/Maillefer, Petrópolis, Brazil).
26
The tooth was then sealed with coltosol (Coltene/Whaledent™, NJ, USA) and composite resin (Filtek™ 3M Espe, Sumaré, Brazil) (Figure 3).
After 3 days, the patient reported no symptoms when she returned for surgical repair of cervical external resorption. The patient was anesthetized, and an intrasulcular incision was made with detachment of the mucoperiosteal flap. The resorption area was exposed and curettage of the granulation tissue was maintained. Subsequently, the area was irrigated copiously with saline solution, the bleeding was controlled, and the cavity was restored with resin-modified glass ionomer cement (Vitremer, 3M, St. Paul, MN, USA). The area was then closed with sutures, which were removed 7 days later (Figure 4). After a follow-up period of 18 months, the patient reported no symptoms and examination revealed a lack of periapical changes (Figure 5).
CASE REPORT 2
A 25-year-old man was referred to the Dental Trauma Service at the Piracicaba Dental School (UNICAMP) for evaluation of tooth 21. During the anamnesis, the patient reported experiencing dental trauma at the age of 7, but he did not remember the details of the accident. Clinically, the dental crown was not darkened, and all anterior teeth responded to the sensitivity test (Endo-Frost, Roeko, Langenau, Germany). The patient reported no pain upon percussion or palpation. Radiographic examination revealed the absence of periapical lesions, but internal inflammatory resoprtion in tooth 21 (Figure 6). Given these clinical observations, endodontic treatment was indicated.
After the patient underwent anesthetic procedures, cavity access, absolute isolation, and initial instrumentation of the root canal were performed by using nickel-titanium (NiTi) hand files (Dentsply Maillefer, Ballaigues, Switzerland). Chlorhexidine gel 2% (Endogel, Itapetininga, Brazil) was used during mechanical preparation. During this stage, there was profuse bleeding within the canal. The canal was irrigated with saline solution, and an intracanal medication, which was a combination of 2% chlorhexidine gel
27
and calcium hydroxide, was manipulated and inserted by using lentulo spirals. The tooth was sealed coronally with coltosol (Coltene/Whaledent™, NJ, USA) and composite resin (Filtek ™3M Espe, Sumaré, Brazil). We recommended that the patient undergo CBCT in order to assess the communication between the resorption and periodontal ligament, which would have justify the profuse bleeding.
The patient returned after 15 days, and he reported no symptoms. The images revealed that the resorption had well-defined limits with the absence of communication (Figure 7). Following anesthetization of the patient, the restoration was removed and the tooth was isolated. The intracanal medication was removed with profuse saline irrigation. Odontometry was performed by using an electronic apex locator (Novapex, Forum Technologies, Richion, Le-Zion, Israel) and was confirmed by hand files. Instrumentation was completed with ProTaper Rotary instruments (Dentsply Maillefer, Ballaigues, Switzerland). The canal was irrigated with 3 mL of 17% EDTA and 5 mL of saline and was dried with paper points. Subsequently, filling was performed by using gutta-percha thermoplastification and AH Plus sealer (Dentsply/Maillefer, Petrópolis, Brazil). After a follow-up period of 24 months, the patient reported no symptoms and examination revealed a lack of periapical changes (Figure 8).
DISCUSSION
Pathological root resorptions lead to irreversible loss of tooth structure, and progression of resorption can cause tooth loss if the process is not stopped (3,5). The main etiological factors of resorption are related to dental trauma, orthodontic movement, internal bleaching, periodontal treatment, and idiopathic causes (15,16,17). In this report, the two patients presented with a history of trauma in their anterior teeth.
Diagnosis of root resorption depends on careful clinical and radiographic analysis. Moreover, conventional radiographic techniques have been shown to reveal limited information on the true extent and nature of the resorptive lesion (3). Thus, CBCT has
28
become an important diagnostic tool for the detection of resorption because it provides three-dimensional imaging (9,10,11). Several studies have emphasized the importance of CBCT for the diagnosis and determination of the treatment plan for root resorption. Recent studies have reported the superior accuracy of CBCT in the detection and location of root resorption compared to periapical radiographs (5,9,18). A CBCT scan was requested for both of the cases described in this study. In case 1, the use of CBCT helped to determine the position and depth in relation to the root canal and, ultimately, the restorability of the tooth. In case 2, no communication was observed between the root canal and periodontal ligament, ensuring the determination of an appropriate treatment plan.
Treatment of external cervical resorption depends on the extent of resorption. Heithersay (15) divided this condition into four classes according to the degree of damage to the mineralized tissues. Class I corresponds to a small, invasive resorptive lesion near the cervical area with shallow penetration into the dentin; class II corresponds to a well-defined resorptive lesion close to the coronal pulp chamber with little or no extension into the radicular dentin; class III corresponds to a resorptive defect involving the coronal third of the root; and class IV corresponds to a resorptive defect extending beyond the cervical third of the root. In class I and II resorptions, the canal can be preserved and resorption can be restored with composite resin or glass ionomer cement. The prognosis of class III and IV resorptions is more uncertain because the treatment is more complex in these cases (19,20). In clinical case 1, cervical resorption was classified as type II after examining the CBCT; however, endodontic treatment was performed because the tooth did not respond to pulp sensitivity tests. After surgery, glass ionomer cement was selected as the material for sealing the resorbed area, as proposed by Heithersay (15).
Internal resorption is characterized by intraradicular destruction of the dentin and dentinal tubules because of clastic cell action (2,3,16); this type of resorption can be confused with external resorption in many situations. Endodontic treatment is preferred for internal resorption if the tooth can be restored and the prognosis is favorable. The aim of the endodontic treatment is to eliminate the inflamed pulp tissue that can support and stimulate resorption (2). If no therapy is established, resorption progression may lead to communication of the root canal with the periodontal ligament. A complete root canal filling
29
with mineral trioxide aggregate (MTA) is indicated when communication is present (2,21,22). In clinical case 2, internal resorption was confined within the root canal. We attempted to preserve as much tooth structure as possible while performing coronal opening during endodontic treatment. Heavy bleeding occurred during instrumentation due to the presence of inflamed pulp and granulation tissue; this impaired our ability to view the canal, even with the aid of a surgical microscope. Therefore, a temporary dressing that included calcium hydroxide and 2% chlorhexidine gel was used between sessions in order to allow subsequent root canal filling. The use of calcium hydroxide as an interappointment dressing maximizes the effect of disinfection procedures, helps control bleeding, and necrotizes residual pulp tissue (5,8,19,23,24,25).
An early and accurate differential diagnosis is essential for the successful treatment of root resorption. The advent of CBCT has helped to improve the clinical diagnosis of resorption. However, because these lesions are asymptomatic in many cases, the use of radiographs during routine dental examinations is essential for the detection of early-stage resorption.
CONCLUSION
The inclusion of CBCT as a complementary examination in endodontics has facilitated the ability to detect root resorption and to determine the exact location. Clinical and radiographic data allow the clinician to make a differential diagnosis between external and internal resorption and to ensure that an appropriate treatment plan is determined for each case.
30 REFERENCES
1 - Harokopakis-Hajishengallis E. Physiologic root resorption in primary teeth: molecular and histological events. J Oral Sci. 2007; 49: 1–12.
2 - Patel S, Ricucci D, Durak C, Tay F. Internalroot resorption: a review.J Endod. 2010; 36: 1107-21.
3 - Patel S, Pitt Ford TR. Is the resorption external or internal? Dent Update. 2007; 34: 218– 29.
4 - Bhuva B, Barnes JJ, Patel S. The use of limited cone beam computed tomography in the diagnosis and management of a case of perforating internal root resorption. Int Endod J 2011; 44: 777–786.
5 - Patel S, Kanagasingam S, Pitt Ford T. Externalcervicalresorption: a review.J Endod. 2009; 35: 616-25.
6 - Durack C, Patel S. Cone Beam Computed Tomography in Endodontics. Braz Dent J. 2012; 23: 179-191.
7 - Gunraj MN. Dental root resorption Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999; 88:647-53.
8 - Nilsson E, Bonte E, Bayet F, Lasfargues JJ. Management of internal root resorption on permanent teeth. Int J Dent. 2013.doi: 10.1155/2013/929486
9 - Durack C, Patel S, Davies J, Wilson R, Mannocci F. Diagnostic accuracy of small volume cone beam computed tomography and intraoral periapical radiography for the detection of simulated external inflammatory root resorption. Int Endod J. 2011; 44: 136- 147.
10 - Tyndall DA, Kohltfarber H. Applications of cone beam volumetric tomography in endodontics. Aust Dent J. 2012; 57: 72–81.
31
11 - Ball RL, Barbizam JV, Cohenca N. Intraoperative. Endodontic Applications of Cone-Beam Computed. J Endod. 2013; 39: 548–57.
12 - Hassan B, Metska ME, Ozok AR, van der Stelt P, Wesselink PR. Detection of vertical root fractures in endodontically treated teeth by a cone beam computed tomography scan.J Endod. 2009; 35, 719–22.
13 - Khedmat S, Rouhi N, Drage N, Shokouhinejad N, Nekoofar MH. Evaluation of three imaging techniques for the detection of vertical root fractures in the absence and presence of gutta-percha root fillings.Int Endod J. 2012; 45, 1004–9.
14 - Haghanifar S, Moudi E, Mesgarani A, Bijani A, Abbaszadeh N. A comparative study of cone-beam computed tomography and digital periapical radiography in detecting mandibular molars root perforations.Imaging Sci Dent. 2014; 44: 115-9.
15 - Heithersay GS. Clinical, radiologic and histopathologic features of invasive cervical resorption. Quintessence Int. 1999; 30: 27–37.
16 - Fuss Z, Tsesis I, Lin S. Root resorption: diagnosis, classification and treatment choices based on stimulation factors. Dent Traumatol 2003; 19: 175–82.
17 - Liang H, Burkes EJ, Frederiksen NL. Multiple idiopathic cervical root resorption: systematic review and report of four cases. Dent Radiol. 2003; 32: 150–5.
18 - Kim E, Kim K-D, Roh B-D, Cho Y-S, Lee S-J. Computed tomography as a diagnostic aid for extracanal invasive resorption. J Endod. 2003;29: 463-5.
19 - Nikolidakis D, Nikou G, Meijer GJ, Jansen JA. Cervical external root resorption: 3-year follow-up of a case. J Oral Sci. 2008; 50: 487-91.
20 - Roig M, Morelló S, Mercadé M, Durán-Sindreu F. Invasive cervicalresorption: report on two cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010; 110: 64-9.
21 - Altundasar E, Demir B. Management of a perforating internal resorptive defect with mineral trioxode aggregate: A case report. J Endod 2009; 35:1441-4.
32
22 - Jacobovitz M, de Lima RK. Treatment of inflammatoryinternalroot resorption with mineral trioxide aggregate: a case report. Int Endod J. 2008; 41: 905-12
23 - Bystro¨m A, Claesson R, Sundqvist G. The antibacterial effect of camphorated paramonochlorophenol, camphorated phenol and calcium hydroxide in the treatment of infected root canals. Endod Dent Traumatol 1985; 1: 170–5.
24 - Sjgoren U, Figdor D, Spangberg L, Sundqvist G. The antimicrobial effect of calcium hydroxide as a short-term intracanal dressing. Int Endod J. 1991; 24: 119–25.
25 - Hedge N, Hedge MN. Internal and external root resorption management: a report of two cases. Int J Clin Pediatr Dent 2013; 6: 44-7.
Figure 1: Cervical external resorption of maxillary left central incisor (a) Clinical aspects (b) Radiographic aspects.
FIGURES
3
34
35
36
Figure 4: Surgical access of cervical external resorption: (a) Clinical aspects (b) Incision (c) Surgical exposure of resorption (d) Restoration with glass ionomer (e,f) Clinical aspects after suture.
3
37
Figure 5: 18 months follow-up: (a) Clinical aspects (b) Radiographic aspects.
3
38
Figure 6: Internal inflammatory resorption of maxillary left central incisor (a) Clinical aspects (b) Radiographic aspects.
3
39
40
Figure 8: Endodontic treatment (a) Final radiographic (b) 24 months follow-up.
4
41 CONSIDERAÇÕES GERAIS
Justificativa da pesquisa
As reabsorções radiculares são complicações frequentes após traumatismos dentários, principalmente nas luxações e reimplantes. Essas sequelas podem se desenvolver semanas, meses ou anos após o acidente traumático. Consolaro (2012) afirmou que as reabsorções inflamatórias podem ser detectadas, aproximadamente, 15 dias após o traumatismo, porém, elas podem estar presentes, mesmo que paralisadas, após longos períodos após o trauma. Diferentemente, a reabsorção por substituição é um processo progressivo e que só pode ser verificado radiograficamente após três meses depois de realizado o reimplante.
O diagnóstico de reabsorções é bastante complexo. As radiografias periapicais, por oferecerem uma imagem bidimensional, são imprecisas na detecção de reabsorções, principalmente nas superfícies vestibular e palatina/lingual. Entretanto, esse é o recurso mais utilizado nas pesquisas clínicas para detecção de reabsorções radiculares em dentes traumatizados. Atualmente, a tomografia computadorizada de feixe cônico apresenta-se como uma ferramenta complementar para visualização de áreas que não foram observadas por meio de radiografias periapicais.
Visto que as reabsorções radiculares são sequelas comuns após traumatismos dentários severos, torna-se necessário um estudo clínico que avalie a precisão das radiografias periapicais na deteccção desse tipo de sequela. Grande parte dos cirurgiões-dentistas usam apenas este recurso radiográfico para o diagnóstico de reabsorções, sendo que, muitas vezes, é necessária a complementação por meio da tomografia computadorizada de feixe cônico para a determinação da localização, extensão e gravidade da reabsorção radicular, o que auxiliaria na decisão do melhor plano de tratamento para cada caso.
