UNIVERSIDADE FEDERAL FLUMINENSE FACULDADE DE ODONTOLOGIA
Medidas cefalométricas tridimensionais utilizadas
em tomografia computadorizada de feixe cônico:
Uma Revisão Sistemática
UNIVERSIDADE FEDERAL FLUMINENSE FACULDADE DE ODONTOLOGIA
Medidas cefalométricas tridimensionais utilizadas
em tomografia computadorizada de feixe cônico:
Uma Revisão Sistemática
LUIZA PAIVA BITTENCOURT Dissertação apresentada à Faculdade de Odontologia da Universidade Federal Fluminense, como parte dos requisitos para obtenção do título de Mestre, pelo Programa de Pós-Graduação em Odontologia.
Área de Concentração: Odontologia
Orientador: Prof. Dr. Alexandre Trindade Simões da Motta
Niterói 2015
BANCA EXAMINADORA
Prof. Dr. Alexandre Trindade Simões da Motta Instituição: Faculdade de Odontologia UFF
Decisão: _________________________Assinatura:_________________________
Profa. Dra. Cláudia Trindade Mattos Instituição: Faculdade de Odontologia UFF
Decisão: _________________________Assinatura:_________________________
Prof. Dr. Felipe de Assis Ribeiro Carvalho Instituição: Faculdade de Odontologia UERJ
AGRADECIMENTOS
Primeiramente gostaria de agradecer a Deus.
Ao Fernando, que sempre me incentivou a cursar o mestrado e crescer profissionalmente. Sua ajuda foi fundamental para a realização deste curso. Obrigada por sua dedicação, amor e companheirismo.
À minha família, em especial aos meus pais, por estarem sempre presentes com palavras de apoio e afeto. À minha irmã Renata que me faz querer ser uma pessoa melhor.
Aos meus colegas da turma de Especialização em Ortodontia da UFF que se tornaram grandes amizades.
Ao Dr. Estélio Zen pelos ensinamentos de vida, orientação e carinho.
Ao meu orientador Dr. Alexandre Trindade Simões da Motta a quem admiro, e pela forma serena e educada com que me orientou e passou seus conhecimentos.
Ao Dr. José Nelson Mucha por seus ensinamentos e por ter um papel importante na minha vida profissional.
Ao Dr. Oswaldo de Vasconcellos Villela por estar à frente da coordenação do curso e nos proporcionar conhecimentos dentro e fora da ortodontia.
À Dra Adriana de Alcântara Cury Saramago pela maneira carinhosa e minuciosa com que leciona.
À Dra. Claudia Trindade Mattos pela disponibilidade em me ajudar, logo nos primeiros passos do meu trabalho e para a conclusão dele.
Aos demais professores do Departamento de Ortodontia da UFF, Dra. Andréa Fonseca Jardim da Motta, Dra. Beatriz de Souza Vilella e Dra Mariana Martins e Martins pela agradável convivência.
Um agradecimento especial à Daniele Masterson, bibliotecária da UFRJ, pela disponibilidade e atenção com que sempre me recebeu.
Aos colegas de turma pela animada e enriquecedora convivência, em especial ao Ricardo Machado pela ajuda na leitura dos artigos.
Aos demais alunos do curso de especialização e mestrado. À Dona Elizete por ser sempre solicita e pela simpatia.
RESUMO
Bittencourt LP. Medidas cefalométricas tridimensionais utilizadas em tomografia computadorizada de feixe cônico: Uma Revisão Sistemática [dissertação].
Niterói: Universidade Federal Fluminense, Faculdade de Odontologia; 2015.
Diversas análises cefalométricas tradicionais são amplamente utilizadas para a avaliação craniofacial na Ortodontia, entretanto as imagens bidimensionais (2D) possuem algumas limitações. Com o desenvolvimento da tomografia computadorizada de feixe cônico (CBCT, do inglês cone beam computed
tomography) o diagnóstico de imagens tomográficas tridimensionais (3D) vem sendo
intensificado. Alguns estudos propuseram novas medidas e até análises cefalométricas organizadas, mas não existe um consenso sobre as medidas a serem utilizadas, dificultando a normatização de uma análise 3D. Através de uma revisão sistemática, foi realizada uma busca em diferentes bases de dados (PubMed, Lilacs,
Web of Science, Scopus e Cochrane Library) com o objetivo de identificar as
medidas cefalométricas utilizadas em imagens tridimensionais do complexo crânio-maxilo-facial. Adotando critérios de inclusão e exclusão pré-estabelecidos foi possível selecionar 10 trabalhos que realizassem medidas nos três planos do espaço (anteroposterior, transversal e vertical) na maxila, mandíbula, dentes e estruturas do crânio. Só foram realizadas medidas em tecido duro. Os estudos foram divididos em três tipos: 1. avaliaram a reprodutibilidade e confiabilidade na realização das medidas apresentadas; 2. apresentaram medidas para uma análise tridimensional de diagnóstico; 3. analisaram efeitos de algum tipo de tratamento realizado. Os resultados mostraram que existe um número grande e variado de medidas, no entanto não se encontrou um formato semelhante nas medições. De 10 títulos selecionados foi possível compilar as medidas que se repetiram mais de uma vez nos estudos selecionados e estas parecem indicar alguma tendência que poderá sugerir uma nova análise cefalométrica tridimensional. Futuros trabalhos devem ser desenvolvidos com o objetivo de padronizar medidas cefalométricas tridimensionais que constituam análises ao mesmo tempo abrangentes e de fácil aplicação pelo ortodontista clínico.
Palavras-chave: tomografia computadorizada de feixe cônico; imagem
ABSTRACT
Bittencourt LP. Three-dimensional cephalometric measurements used in CT cone beam: a systematic review. [dissertation]. Niterói: Universidade Federal Fluminense, Faculdade de Odontologia; 2015.
Several traditional cephalometric analyzes are widely used for craniofacial assessment in orthodontics, however the two-dimensional images (2D) have some limitations. With the development of cone beam computed tomography (CBCT) three-dimensional radiographic diagnosis (3D) has been intensified. With the use of specific software you can perform linear and angular measurements reproducibly and reliably, some studies have proposed new measures and to cephalometric analyzes organized, but there is no consensus on the measures to be used, making the standardization of a 3D analysis. Through a systematic review, a search on different databases was performed (PubMed, Lilacs, Web of Science, Scopus and Cochrane Library) with the objective of identifying the cephalometric measurements used in three-dimensional images of cranio-maxillo-facial complex. Adopting inclusion criteria and preset exclusion was possible to select 10 works which carries out measurements in the three spatial planes (anteroposterior, transverse and vertical) in the jaw, jaw, teeth and skull structures. The measurements were performed only in hardtissue. The studies were divided into three types: 1. evaluated the reproducibility and reliability in carrying out the measures presented; 2. presented measures for a three-dimensional analysis of diagnosis; 3. examined the effects of any treatment performed. The results showed that there is a large and varied number of measures, however we did not find a similar format in measurements. It was possible to compile the measures that were repeated more than once in the selected studies and these seem to indicate any trend that may suggest a new three-dimensional cephalometric analysis. Future studies should be developed in order to standardize dimensional cephalometric measurements in order to constitute analysis that are at the same time comprehensive and easy to apply for the clinical orthodontist.
Keywords: cone-beam computed tomography; three-dimensional imaging;
1 - INTRODUÇÃO
A cefalometria vem sendo utilizada em Ortodontia como uma técnica de avaliação craniofacial através de tomadas radiográficas padronizadas, desde a criação do cefalostato por Broadbent em 1931. A partir desta padronização na aquisição da imagem radiográfica, vários estudos foram realizados para avaliar o crescimento e desenvolvimento craniofacial. Posteriormente, foram criadas diversas análises bidimensionais (2D) utilizando as medidas cefalométricas a partir de pontos, linhas e planos de referência. Essas análises permitiram que as informações fornecidas pela imagem radiográfica tivessem aplicabilidade no diagnóstico, planejamento e na avaliação dos resultados do tratamento ortodôntico 1,2,3.
As telerradiografias tradicionais fornecem imagens bidimensionais que são usadas para retratar estruturas craniofaciais que, na realidade, são tridimensionais. Portanto, elas apresentam limitações como: distorções e ampliações das imagens; superposição de estruturas cranianas; superposição dos lados direito e esquerdo sobre o plano sagital mediano, dificultando a identificação de diferenças entre os lados; e dificuldade em identificar possíveis deformidades esqueléticas na área do terço médio da face. O posicionamento da cabeça do paciente no momento da tomada radiográfica também pode comprometer a qualidade da imagem a ser avaliada4,5.
A tomografia computadorizada foi desenvolvida no início da década de 70 e tem grande utilização na Medicina. Este tipo de imagem permite analisar, nos três planos do espaço, a morfologia de estruturas esqueléticas, como as do complexo maxilo-facial, e fornece informações da complexa inter-relação entre eles. Porém, sua aplicação na Odontologia possui limitações relacionadas à necessidade de um considerável espaço físico, e, principalmente, por emitir elevados níveis de radiação ao paciente, além do alto custo para aquisição das imagens 6,7,8.
A partir de 1998, com o desenvolvimento da tomografia computadorizada de feixe cônico (CBCT, do inglês cone beam computed tomography) para aquisição de imagens pertinentes à odontologia, o diagnóstico tomográfico tridimensional (3D) vem sendo intensificado7,8. A CBCT fornece uma imagem tridimensional de alta
qualidade, extração de dados precisos e quantitativos confiáveis, exposição à radiação reduzida, utilizando equipamento de menor custo9,10.
Uma vez adquiridos os cortes tomográficos do crânio do paciente através da CBCT, torna-se necessário reformatar ou reconstruir a imagem tridimensional em formato DICOM (digital imaging and communications in medicine). Para isso foram criados softwares para processar, gerenciar e analisar as imagens em 3D. Através destes softwares é possível realizar a identificação dos pontos de referência, medições quantitativas e a segmentação tridimensional das regiões de interesse para a Ortodontia11,12.
Atualmente, os softwares disponíveis permitem realizar medições lineares e angulares em imagens tridimensionais para o desenvolvimento de análises radiográficas tridimensionais13. Estas parecem suprir algumas limitações das
análises cefalométricas já consagradas, que são realizadas em telerradiografias bidimensionais.
Para validar esse novo meio de diagnóstico, diversos estudos foram desenvolvidos para analisar a confiabilidade e reprodutibilidade na marcação dos pontos e também das medições craniofaciais feitas em imagem tridimensional, mostrando que é possível reproduzir pontos e medidas neste tipo de imagem14-20.
Alguns estudos realizaram medições lineares e angulares semelhantes às utilizadas na cefalometria convencional21,22 utilizando os mesmos pontos, planos e
linhas de referência. Entretanto, a avaliação dos lados direito e esquerdo, separadamente, demonstra ser um importante diferencial nas análises 3D.
Existem propostas de novas medidas e até análise cefalométrica organizadas8,12,23-25. Algumas propostas são adaptadas para algum tipo de
tratamento, como no caso de medições no sentido transversal para avaliar os efeitos de uma disjunção maxilar26,27. Entretanto, não existe um consenso sobre as medidas
a serem utilizadas, dificultando a normatização de uma análise tridimensional. O objetivo deste trabalho foi avaliar, por meio de uma revisão sistemática, a utilização da CBCT em análise cefalométrica tridimensional, definindo as medidas utilizadas pelos autores na avaliação do complexo maxilo-facial para auxiliar no diagnóstico, planejamento e avaliação de resultados do tratamento ortodôntico.
2 - METODOLOGIA
O protocolo para a revisão sistemática foi registrado no National Institute of
Health Research Database (www.crd.york.ac.uk/prospero/Protocol: CRD42015016241). O método utilizado neste estudo foi baseado nas diretrizes publicadas no PRISMA Statement28. Com o auxílio de uma bibliotecária
especializada em bancos de dados em ciências da saúde foram criadas estratégias de busca para identificar os artigos relevantes ao assunto com o objetivo de responder à pergunta criada por meio do formato PICO (Quadro 1). As bases de dados selecionadas para esta revisão foram: Medline (via PubMed), Lilacs, Web of
Science, Scopus e Cochrane Library. A estratégia de busca foi elaborada em três
principais índices de pesquisa: título, resumo e assunto e foram desenhadas de acordo com a especificidade de cada base de dados combinadas com os operadores boleanos “OR” para adição e “AND” para relação dos termos. Sempre que possível, utilizando o vocabulário controlado de descritores de assunto (Mesh/Medline, e DeCs/BVS). Além disso, foram utilizados termos livres pesquisados nas principais revistas, bem como nas referências, resumos e comentários de artigos relacionados com a finalidade de aumentar a sensibilidade da busca. A organização dos protocolos seguem na Tabela I.
P- População Medidas cefalométricas utilizadas em CBCT
I – Intervenção Diagnóstico e planejamento ortodôntico
C – Comparação Entre as medidas mais frequentemente utilizadas
O – “Outcome”-Resultados
esperados
Medidas tridimensionais para diagnóstico e planejamento ortodôntico
Pergunta Quais são as medidas mais frequentemente utilizadas emimagem tridimensional para diagnóstico e planejamento ortodôntico?
Hipótese Nula
Não é possível determinar quais as medidas
tridimensionais mais frequentemente em CBCT utilizadas para diagnóstico e planejamento ortodôntico
Remove o PICO da dissertação? Quadro 1. Formato PICO
Base de Estratégia de busca
dados
Pubmed:
(((Cone-beam Computed Tomography[mh] OR "Cone-beam Computed Tomography"[tiab] OR "CBCT"[tiab] OR "Cone-beam CT" OR "CBCT scans" OR Imaging, Three-Dimensional[mh] OR "Three-Dimensional Image"[tiab] OR "Computer Generated 3D Imaging"[tiab] OR "Computer-Assisted Three-Dimensional Imaging"[tiab]) AND (("1998/01/01"[PDat] : "2015/01/31"[PDat]) AND Humans[Mesh]))) AND ((Cephalometry[mh] OR "Cephalometric measurement"[tiab] OR "Three-dimensional analysis"[tiab] OR "3D analysis"[tiab] OR "Linear measurements"[tiab] OR "Angular measurements"[tiab] OR "Maxillo-mandibular measurements"[tiab] OR "Cranio-facial measurements"[tiab] OR "Three-dimensional measurement"[tiab] OR "3D measurement"[tiab] OR "Three-"Three-dimensional linear measurement"[tiab] OR "3D linear measurement"[tiab] OR "Three-dimensional angular measurement"[tiab] OR "3D angular measurement"[tiab]) AND (("1998/01/01"[PDat] : "2015/01/31"[PDat]) AND Humans[Mesh]))
Scopus:
3D Imaging" OR "Computer-Assisted Three-Dimensional Imaging" ) ) AND ( TITLE-ABS-KEY ( cephalometry OR "Cephalometric measurement" OR "Three-dimensional analysis" OR "3D analysis" OR "Linear measurements" OR "Angular measurements" OR "Maxillo-mandibular measurements" OR "Cranio-facial measurement" OR "Three-dimensional measurement" OR "3D measurement" OR "Three-dimensional linear measurement" OR "3D linear measurement" OR "Three-dimensional angular measurement" OR "3D angular measurement" ) ) AND ( LIMIT-TO ( PUBYEAR , 2015 ) OR LIMIT-TO ( PUBYEAR , 2014 ) OR TO ( PUBYEAR , 2013 ) OR TO ( PUBYEAR , 2012 ) OR LIMIT-TO ( PUBYEAR , 2011 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 2010 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 2009 ) OR TO ( PUBYEAR , 2008 ) OR TO ( PUBYEAR , 2007 ) OR LIMIT-TO ( PUBYEAR , 2006 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 2005 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 2004 ) OR TO ( PUBYEAR , 2003 ) OR TO ( PUBYEAR , 2002 ) OR LIMIT-TO ( PUBYEAR , 2001 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 2000 ) OR LIMIT-LIMIT-TO ( PUBYEAR , 1999 ) OR LIMIT-TO ( PUBYEAR , 1998 ) ) AND ( LIMIT-TO ( SUBJAREA , "DENT" ) ) AND ( LIMIT-TO ( DOCTYPE , "ar" ) OR LIMIT-TO ( DOCTYPE , "re" ) OR LIMIT-TO ( DOCTYPE , "ip" ) )
Web of Science:
(("Cone-beam Computed Tomography" OR "CBCT" OR "Cone-beam CT" OR "CBCT scans" OR “Three-Dimensional Imaging” OR "Three-Dimensional Image" OR "Computer Generated 3D Imaging"OR "Computer-Assisted Three-Dimensional Imaging")) AND ((“Cephalometry” OR "Cephalometric measurement" OR "Three-dimensional analysis" OR "3D analysis" OR "Linear measurements" OR "Angular measurements" OR "Maxillo-mandibular measurements" OR "Cranio-facial measurement" OR “Three-dimensional measurement” OR “3D measurement” OR “Three-dimensional linear measurement” OR “3D linear measurement” OR “Three-dimensional angular measurement” OR “3D angular measurement”))
Lilacs:
tw:( (tw:(tomografia computadorizada de feixe cônico (mh))) OR (tw:(tomografia computadorizada por feixe cônico)) OR (tw:(cbct)) OR (tw:(cone-beam ct)) OR (tw:(cbct scans)) OR (tw:(three-dimensional imaging)) OR (tw:(imagens tridimensionais)) OR (tw: (imágenes tridimensionales)) OR (tw:(three-dimensional image)) OR (tw:(imagem tridimensional)) OR (tw:(imagen tridimensional)) OR (tw:(computer generated 3d imaging)) OR (tw:(imagem 3d gerada por computador)) OR (tw:(imagen generada por ordenador 3d)) OR (tw:(computer-assisted three-dimensional imaging)) OR (tw:(imagens tridimensionais assistida por computador)) OR (tw:(imagen tridimensional asistida por ordenador)) AND (tw: (cefalometria (mh))) OR (tw:(cephalometric measurement)) OR (tw:(medição cefalométrica)) OR (tw:(medición cefalométrica)) OR (tw:(three-dimensional analysis)) OR (tw:(análise tridimensional)) OR (tw:(el análisis tridimensional )) OR (tw:(3d analysis)) OR (tw:(análise 3d)) OR (tw:(análisis 3d)) OR (tw:(linear measurements)) OR (tw:(medidas lineares)) OR (tw: (medidas lineales)) OR (tw:(angular measurements)) OR (tw:(medidas angulares)) OR (tw: (las mediciones angulares)) OR (tw:(maxillo-mandibular measurements)) OR (tw:(medições maxilo-mandibular)) OR (tw:(mediciones maxilo-mandibular)) OR (tw:(cranio-facial measurement)) OR (tw:(medição crânio-facial)) OR (tw:(craneo-facial medición)) OR (tw: (three-dimensional measurement)) OR (tw:(medição tridimensional)) OR (tw:(medición tridimensional)) OR (tw:(3d measurement)) OR (tw:(medição 3d)) OR (tw:(medición 3d)) OR (tw:(three-dimensional linear measurement)) OR (tw:(medida linear tridimensional)) OR (tw: (medición lineal tridimensional)) OR (tw:(3d linear measurement)) OR (tw:(medida linear 3d)) OR (tw:(medición lineal 3d)) OR (tw:(three-dimensional angular measurement)) OR (tw: (medición angular tridimensional)) OR (tw:(3d angular measurement)) OR (tw:(medição angular 3d)) OR (tw:(medición angular 3d))) AND (instance:"regional")
Tabela 1. Relação entre as bases de dados, estratégias de busca utilizadas e o número total de artigos encontrados.
The Cochrane
Library
#1cone-beam tomography or CBCT or cone-bem CT or CBCT scans:ti,ab,kw #2cone-beam computed tomography Publication Year from 1998 to 2015
#3"dimensional image" or "computer generated 3D imaging" or "computer-assisted three-dimensional imaging":ti,ab,kw Publication Year from 1998 to 2015
#4"three-dimensional imaging" Publication Year from 1998 to 2015 #5 #1 or #2 or #3 or #4
#6"three-dimensional analysis" or "3D analysis":ti,ab,kw Publication Year from 1998 to 2015 #7"linear measurements" or "angular measurements":ti,ab,kw Publication Year from 1998 to 2015 #8"maxillo-mandibular measurement" or "cranio-facial measurement":ti,ab,kw Publication Year from 1998 to 2015
#9"three-dimensional measurement" or "3D measurement":ti,ab,kw Publication Year from 1998 to 2015
#10"three-dimensional linear measurement" or "3D linear measurement" or "three-dimensional angular measurement" or "3D angular measurement":ti,ab,kw Publication Year from 1998 to 2015 #11cephalometry Publication Year from 1998 to 2015
#12 #6 or #7 or #8 or #9 or #10 #13 #5 and #12
A identificação dos estudos relacionados ao assunto da investigação foi realizada de Janeiro de 1998 até Janeiro de 2015, sem restrição com relação ao idioma empregado na redação dos artigos. Também foi realizada busca manual nas referências dos artigos para selecionar possíveis trabalhos relevantes.
Os critérios de inclusão para a seleção dos artigos foram: 1. Estudos que utilizassem medidas em imagens tridimensionais; 2. Estudos que analizassem medidas realizadas em todo o complexo crânio-maxilo-facial; 3. Aquisição das imagens em tomografia computadorizada de feixe cônico; 4. Medidas realizadas em humanos ou crânios secos.
Os critérios de exclusão foram: 1. Artigos de cartas ao editor, entrevistas e editoriais; 2. Radiografias convencionais ou imagens 2D a partir de CBCT; 3. Medidas realizadas em estruturas isoladas; 4. Aquisição das imagens em tomografia espiral ; 5. Medidas realizadas em animais ou amostra sintética.
Na fase inicial, os títulos e resumos foram revisados de forma independente por dois leitores (L.P.B e R.M) e as informações obtidas foram comparadas. A leitura completa do texto do artigo foi realizada quando o resumo não estava disponível ou quando o resumo não indicou que os critérios de inclusão estavam cumpridos. Os estudos que não preencheram os critérios de inclusão e que apresentaram incompatibilidade com a pergunta da pesquisa foram excluídos. Conflitos inter-examinadores foram resolvidos por um dos autores (A.T.S.M) em uma reunião de consenso.
Além disso, para aumentar o nível de informação dos estudos e se aproximar à resposta da pergunta PICO, que busca medidas tridimensionais, foram selecionados somente os artigos que apresentassem medidas nos três planos do espaço (anteroposterior, transversal e vertical).
Após a seleção dos artigos que preencheram os critérios de inclusão, foi feita a avaliação da qualidade metodológica de cada um deles, seguindo as recomendações do Manual Cochrane de Revisões Sistemáticas (versão 5.1.0)29.
Seis domínios específicos para este estudo foram elaborados para avaliar se houve uma descrição: 1. das características dos indivíduos da amostra; 2. do software utilizado; 3. da identificação dos pontos de referência; 4. das medidas realizadas; 5. do objetivo e utilidade das medidas; 6. dos valores das medidas realizadas. Os estudos foram classificados de acordo com os seguintes critérios: baixo risco de viés, se cinco ou mais domínios foram considerados adequados; risco moderado de viés, se três ou mais domínios foram registrados com "sim"; alto risco de viés, se o estudo registrou "sim" em menos de três domínios.
3 - ARTIGOS PRODUZIDOS
Three-dimensional cephalometric measurements used in cone beam CT– a systematic review
Luiza Paiva Bittencourt, MSc student (UFF) Ricardo Martins Machado, MSc student (UFF)
Daniele Masterson T. P. Ferreira, Library science specialist (UFRJ) Alexandre Trindade da Motta, Associate professor (UFF)
Department of Orthodontics, School of Dentistry, Federal Fluminense University, Niterói, Rio de Janeiro, Brazil
*Corresponding author: Luiza Paiva Bittencourt – Federal Fluminense University / School of Dentistry - Rua Mário Santos Braga, no 30 - Campus Valonguinho, Centro, Niterói, RJ, Brazil
- CEP 24040-110 - Phone: 55 21 2629-9823 e-mail: luizapaiva@ig.com.br
Aim: Thanks to the development of cone beam computed tomography (CBCT)
diagnosis using three-dimensional tomographic images (3D) has become widespread. Material and Methods: Through a systematic review, a search on different databases (PubMed, Lilacs, Web of Science, Scopus and Cochrane Library) was performed with the purpose of identifying the cephalometric measurements used in three-dimensional images of the craniomaxillofacial complex. By adopting preset inclusion and exclusion criteria, 10 works were selected which performed measurements in the three planes of space (anteroposterior, transverse and vertical) i.e. in the maxilla, mandible, teeth and skull structures. Measurements were only carried out on hard tissue. The study comprised three measure types: 1. To evaluate reproducibility and reliability in carrying out the measurements; 2. To carry out measurements for a three-dimensional diagnostic analysis; 3. To analyze the effects of a given treatment. Results: The results showed that there is a large and varied number of measures, but no similar format was found in the measurements. It was possible to compile measures that were repeated more than once in the selected studies, and these seem to indicate a some sort of trend, which may suggest a new three-dimensional cephalometric analysis. Conclusion: Future work is warranted in order to standardize three-dimensional cephalometric measures that yield analyses at once comprehensive and streamlined for the clinical orthodontist.
Keywords: cone-beam computed tomography; three-dimensional imaging; cephalometry.
INTRODUCTION
Cephalometrics has been used in orthodontics as a craniofacial evaluation technique through radiographs since the invention of the cephalostat by Broadbent.1
Subsequently, several two-dimensional cephalometric analysis techniques were created which use landmarks, lines and reference planes for measurements.2,3
However, radiographs have some limitations, especially in terms of structure overlapping and magnification.3,4
Since 1998, with the development of cone beam computed tomography (CBCT) to acquire images relevant to dentistry, three-dimensional radiographic diagnostics has grown substantially.7,9 CBCT provides a three-dimensional image of
high quality without structure distortion compared to conventional tomography. Besides, radiation exposure is diminished, and the equipment is more affordable.9,10,17
Currently, the available software includes tools that allow one to perform measurements in three-dimensional images for craniofacial evaluation.13 Several
studies have evaluated the reliability and reproducibility of measurements and landmarks in 3D images, in order to validate this new craniofacial diagnostic method.14-20 Some of these studies conducted linear and angular measurements
similar to those used in conventional cephalometrics21,22 using the same landmarks,
planes and reference lines. However, the ability to evaluate right and left sides separately is a key differentiator in 3D analysis, highlighting the asymmetries in a way hitherto impracticable with 2D methods.
New measures and even organized cephalometric analyses have been proposed.8,12,23-25 No consensus has been reached, however, on which structures,
landmarks and measures to use, which renders the standardization of three-dimensional analysis a real challenge.
Some proposals are highly specific and suitable for any type of treatment, such as measures in the transverse direction aimed at assessing the effects of maxillary expansion.26,27
Despite dramatic improvements in CBCT software, clinicians are still lacking standardized, well-established analysis methods to help them benefit from the advanced features offered by three-dimensional imaging. Being able to use the benefits of 3D cephalometrics with the same ease as traditional 2D analysis would be a diagnostic breakthrough, one much needed to introduce these new methods.
The purpose of this systematic review was to evaluate the use of CBCT in three-dimensional cephalometric analyses, while defining the measures used by the authors in evaluating the maxillofacial complex as a means to carry out diagnosis, planning and evaluation of orthodontic treatment results.
MATERIAL AND METHODS
This systematic review was registered at the National Institute of Health Research Database (www.crd.york.ac.uk/prospero / Registration nº: CRD42015016241). The study conforms to the guidelines published in the PRISMA Statement28 for reporting systematic reviews. With the help of a librarian specializing
in health science databases, search strategies were developed to identify articles relevant to the subject in order to answer the following question: What measures are used in three-dimensional imaging for orthodontic diagnosis and planning?
The databases selected for this review were: Medline (via PubMed), Lilacs,
Web of Science, Scopus and Cochrane Library. The search strategy was developed
on three major research levels, i.e., title, abstract and subject, which are designed according to the specificity of each database combined with the Boolean operators "OR" for addition and "AND" for term relation. Whenever possible, the controlled vocabulary of subject descriptors was employed (Mesh / Medline and DeCS / BVS). Furthermore, some free terms used in major journals were searched, as well as references, abstracts and comments of articles with the purpose of increasing search sensitivity.
The identification of studies related to the subject under investigation was carried out between January 1998 and January 2015, regardless of the language used to compose the articles. A manual search was also performed in the references of the articles included in the study, which might help to select relevant works.
Inclusion criteria for selecting articles were: 1. Studies using three-dimensional measures; 2. Measurements carried out throughout the craniomaxillofacial complex; 3. Acquisition of cone beam computed tomography images; 4. Measurements undertaken in humans or dry skulls.
Exclusion criteria were as follows: 1. Letters to the editor, interviews and editorials; 2. Articles using conventional radiographs or 2D images derived from CBCT; 3. Measurements carried out in isolated structures; 4. Acquisition of spiral CT images; 5. Measurements performed on animals or synthetic samples (phantom).
In the initial phase, the titles and abstracts were reviewed independently by two readers (LPB and RM), and the resulting information was compared. Studies that 14
did not meet the inclusion criteria and were incompatible with the research question were excluded. Interrater conflicts were resolved by one of the authors (ATSM) in a consensus meeting.
Additionally, in order to increase the level of information provided by the studies, and thereby answer the PICO question (patient problem or population (P), intervention (I), comparison (C) and outcome(s) (O)), in handling three-dimensional measurements, only those articles were selected which allowed measurements to be made in the three planes of space (anteroposterior, transverse and vertical); fifteen articles were excluded .
Since no intervention was evaluated, the sample’s randomization and blinding requirements were not considered. With a view to assessing the methodological quality of each criterion, certain criteria were adapted to meet the recommendations of the Cochrane Handbook for Systematic Reviews (version 5.1.0).29 Six specific
areas of this study were designed to assess whether there was a description: 1. The characteristics of the individuals in the sample; 2. The software used; 3. Identification of reference points; 4. Measurements taken; 5. The purpose of the measurements; 6. The purpose of the values measured. The studies were classified according to the following criteria: low risk of bias, if five or more domains were considered appropriate; moderate risk of bias, if three or more domains were registered with "yes"; high risk of bias, only if the study reported "yes" in at least three domains.
RESULTS
Searches on electronic databases yielded 3,219 titles and abstracts, and one article in the search for references, which were inserted into a flow diagram (Figure 1). Among these titles, 2,373 were duplicated and therefore removed. After reading the title, 413 studies were excluded as they bore no relation to the review. All other titles and abstracts (434) were analyzed, 155 of which were considered inappropriate and subsequently deleted. The full texts of 279 studies were evaluated. Finally, 26 articles that fully met the inclusion criteria were selected.
The articles found in the search were classified into three types of study: 1. To evaluate the reproducibility and reliability in carrying out the measurements; 2. To 15
carry out measurements for a three-dimensional diagnostic analysis; 3. To analyze the effects of a given treatment.
Of the 26 articles found in the search results, 17 evaluated the reproducibility and reliability of the measurements, and of these only five12,17,30,31 showed
measurements on the three planes of space, and were therefore included. Of the seven studies involving proposed diagnosis measures six were included since they showed measurements on the three planes.8,21,23-25,32 The two articles that evaluated
the effects of a given procedure could be measured in the three planes, and were thus excluded.
Figure 1. Flow diagram of search results
Thereafter, 11 were evaluated for eligibility and qualified (Table I). Among these articles, there was one with high risk of bias, and was therefore excluded. All 16
Final studies included (n=26) Pubmed (n=1728) The Cochrane Library (n=6) Total records (n=3.220 ) Lilacs (n=98) Web of Science (n=376) Scopus (n=1011) Records after duplicates removed (n=847) Full-text articles assessed for eligibility
(n=279) Records excluded after full-text reading (n=253) (n=) Additional records identified through other sources (n=1) Records screened on title and abstract
(n=434)
Records excluded (n=155)
Excluded medical, dental implants and endodontics
articles, airways and root resorption analysis
cephalometric measurements used in each study were extracted from the 10 remaining studies. All the measurements were made on hard tissue, none on soft tissue (Annex A).
In type one studies, the measurements totaled 183, with 177 linear and six angular. The second type of study comprised a total of 287 measurements, with 198 linear and 89 angular.
Most studies showed linear and angular measurements except three,17,30,31
which were classified as type one, and thus showed only linear measurements. All studies classified as type two included both linear and angular measurements (Table II).
Study Sample Software descriptionPoint Measurementdescription Goal Measurementvalues Risk ofbias
Bayome et al.
2013 Yes Yes Yes Yes Yes Yes Low Berco et al.
2009 No Yes Yes Yes No Yes Moderate Brown et al.
2009 No Yes Yes Yes No Yes Moderate Cheung et al.
2011 Yes Yes Yes Yes Yes Yes Low Cho HJ. 2009 Yes Yes Yes Yes Yes Yes Low
Moreira et al.
2009 No Yes Yes Yes No Yes Moderate Sanders et al.
2010 Yes Yes Yes Yes Yes Yes Low Stratemann et
al. 2008 No Yes Yes Yes No Yes Moderate Van Vlijmen
et al. 2011 No Yes Yes Yes No No High Wong et al.
2011 Yes Yes Yes Yes No No Low Zamora et al.
2013 Yes Yes Yes Yes Yes Yes Low
Table I – Evaluation of methodological quality of selected articles
The best valued measure was in the anteroposterior direction with 168 measurements, followed by vertical analysis with 165, and transverse analysis with 135 measurements. The other category (OT) included two measures presented by Bayome et al.,23 who evaluated the basal curvature of the maxilla and mandible by
marking three and five landmarks, respectively, and applying a mathematical formu 17
Measurement
Direction Measurement type Region Evaluated
Study Measurement AP T V OT Point to Point Point to Plane / Line Among 3 points Plane / Line to Plane / Line OT Mx M d Teeth Cs Mx/ Md Cs/Mx/Md Bayome et al. 2013 14 A21 L 15 10 8 2 14 5 7 7 2 5 17 1 1 11 Berco et al. 2009 29 L 3 5 21 29 9 7 3 10 Brown et al. 2009 16 linear 1 7 8 16 3 4 3 6 Cheung et al. 2011 53 L 19 A 29 16 27 18 34 4 16 4 13 14 16 3 22 Cho HJ. 2009 40 A79 L 38 50 31 12 67 3 37 2 8 69 10 2 28 Moreira et al. 2009 15 L 6 A 7 1 13 15 6 2 3 3 3 10 Sanders et al. 2010 13 L 7 A 11 3 6 13 1 6 9 7 4 Stratemann et al. 2008 117 L 42 35 40 117 16 76 11 2 12 Wong et al. 2011 11 L3 A 9 2 3 10 1 1 2 4 2 3 5 Zamora et al. 2013 21 L6 A 13 6 8 21 6 13 5 1 8 Total 375 L95 A 168 135 165 2 265 107 22 74 2 32 156 108 43 15 116
L = linear; A = angular =; AP = anteroposterior; T = transverse; V = vertical; OT = others; Plane/Line = plane or line; Mx/ Md = relationship between maxilla and mandible; Mx = maxilla; Md = mandible; Cs = cranial structures; C/Mx/Md = relationship between cranial, maxillary and mandibular structures, or both
Table II. Features of the articles included in the study
The studies whose distribution showed more uniform measurements in the three planes of space were those of Bayome et al.,23 Cheung et al.,25 Cho,8
Stratemann et al.17 and Zamora et al.24
The studies presented measures of the point-to-point type, connecting two points on linear measurements; point to plane/line, which measured the distance from a given point to a plane or a reference line; between three points, which performed an angular measurement between plane or line with another plane or reference line. The only studies that had all kinds of measures (Table II) were those of type two,8,21,23,25 with the exception of Sandres et al. and Zamora et al.24,32 Three
studies that were classified as type one had only point-to-point measurements.17,30,31
In following the method of presentation of measurements in some studies,8,21,25,32 the regions evaluated were divided into maxilla, mandible, teeth and
cranial structures, be it singly or in relation to each other (Table II). All selected studies presented some type of measure in the mandible only, as well as in the relationship between skull structures and the maxilla and/or mandible. Studies that did not perform measurements in the maxilla, and individually in the skull structures, analyzed the relationship between them.21,24,30-32 The total outcomes of measurements
from assessed teeth was high (108) due to the study by Cho,8 which presented a
total of 119 measurements, 69 of these dental, while some studies12,23,30,31 did not
carry out any dental measurements at all. Only the studies by Cheung et al.,25 and
Cho and Stratemann et al.8,17 performed measurements in all isolated structures of
the maxillofacial complex.
In order to make a summary of the measurements of the 10 selected articles, which could suggest a three-dimensional analysis, only those that are repeated at least once were selected. Identical points and measurements presented by the authors with different acronyms or abbreviations were standardized for this study (Appendix B). A total of 28 measurements were compiled, 13 in the anteroposterior direction, 5 in the transverse, and 10 in the vertical direction. Of these measures, four in the anteroposterior direction are bilateral (Table III).
Table III. Measurements that are repeated in studies
Anteroposterior (13) Transverse (5) Vertical (10)
SNA (4) SNB (3) ANB (4) ANS-PNS (5) NB-Pg (2) Or-Po (2)* N-Pg/FH (2) Co-Pg (3)* Go-Me (3)* Go-Pg (2)* Co-A (2) L1/MP (2) U1/PP (2) Or-Or (2) Go-Go (4) Co-Co (3) Z-Z (4) Mf-Mf (2) N-Me (4) N-ANS (3) ANS-Me (5) Co-Go (4) N-A (4) N-B (3) N-Pg (3) A-Pg (2) B-Me (2) Cg-Me (2)
(n)= número de vezes que a medida se repete nos estudos * medidas realizadas nos lados direito e esquerdo
In order to make a summary of the measurements of the 10 selected articles, which could suggest a three-dimensional analysis, only those that are repeated at least once were selected. Identical points and measurements presented by the authors with different acronyms or abbreviations were standardized for this study (Appendix B). A total of 28 measurements were compiled, 13 in the anteroposterior direction, 5 in the transverse, and 10 in the vertical direction. Of these measures, four in the anteroposterior direction are bilateral (Table III).
DISCUSSION
Several studies on the use of CBCT12,18,33-37 show that there is growing interest
in using this tool for diagnosing, planning and evaluating treatments performed by orthodontists and maxillofacial surgeons.
On the other hand, projects such as the European Union Sedentexct guidelines recommend that CBCT only be requested when the clinical question that generated the need for the examination cannot be answered appropriately by using conventional radiographs, which feature lower radiation doses. This reinforces the need for creating standardized three-dimensional cephalometric analyses with clear diagnostic objectives, thus justifying the use of this imaging method.34
With the introduction of CBCT in orthodontic diagnosing, new possibilities were opened for the study of craniofacial relationships. However, no 3D cephalometric analyses focusing on clinical use can yet be found in the literature. 20
This probably occurs because studies show a wide variety of measurements, report difficulty in marking certain points.39 Furthermore, proposals for new points and
measurements (including the use of bilateral points) are reported in different ways by the authors, often adapting the measurements to allow them to be applied to the analysis of isolated anatomical structures, or specific treatments such as ortho-surgical or maxillary expansion.
The development of software with different measuring tools and ease of use are crucial for the adoption of CT images in the clinical setting. The software programs found in the studies were: Invivo (Anatomage, San Jose, CA, USA)8,23,24, 3D Dolphin (Dolphin Imaging, Chatsworth, CA, USA),30-32 SimPlant OMS Pro Standalone 12.03 (Materialise NV, Leuven, Belgium),21 Amira software (Amira 3.1, Mercury Computer Systems GmbH, Berlin, Germany),17 Vitrea software 3.8.1 (Vital Images Inc., Plymouth, MN, USA),12 and Maxilim software (Medicim NV, Mechelen, Belgium).25
As in conventional 2D analysis, the goal in creating 3D analysis is for it to be comprehensive and thorough but at the same time clinically viable. It should not encumber the clinician with a lengthy procedure, which might make it too complex, and therefore inconvenient for the clinician.
While performing systematic searches, it was observed that the study samples were not ideally composed of individuals selected randomly and prospectively. Rather, the most serious constraint involved exposure to CBCT radiation, if one is to conform to the ethical requirements of clinical research. Nevertheless, retrospective and transverse studies were found among those that recorded the use of CBCT8,21,24,32 in consecutive individuals as well as analyses of dry skulls12,17,30,31 given
that the latter are the most feasible options. One exception was noted in the work of Cheung et al.,25 which used a sample of 100 individuals, some of them student
volunteers who signed a consent form to undergo CBCT.
Most works described correctly the image acquisition protocol, providing the amplitude of the FOV (field of view), which should encompass the entire head. 17,21,23-25,30-32 However, other studies failed to provide these data.8,12 All studies, with the
exception of Cho,8 described the voxel used, which was always lower in studies that
used dry skull samples (0.20 mm and 0.25 mm)12,17,30,31 vs. studies with human
samples (0.4mm)8,21,24,25,32, which is probably related to radiation doses.
Image acquisition was performed with different scanners, among which the most frequently used was i-CAT® (Imaging Sciences International, Hatfield,
PA).8,12,2124,25,30-32 Zamora et al. compared the use of two scanners, the NewTomH QR
DVT 9000 (Aperio Inc., Sarasota, FL), and the CB MercuRayTM (Hitachi Medical Technology, Tokyo, Japan). Bayome et al. employed the Alphard 3030 (Asahi Roentgen Ind. Co. Ltd., Kyoto, Japan). Head positioning during image acquisition was described only by Moreita et al. and Stratemann et al.,12,17 where their major
concern was to make sure the entire area of the head was included, especially the Porion (Po) since many studies used the Frankfort horizontal plane (FH).
Many of the proposed measures can be used for a specific but not a routine analysis. In the study by Baka et al.,26 an analysis was performed to assess crossbite
by comparing the left and right sides separately with respect to the sagittal plane before and after maxillary expansion, analyzing tooth inclinations and skeletal relationships. The analysis provides interesting data but its use is circumscribed to this specific type of malocclusion and treatment.
None of the selected studies performed measurements of soft tissue on the CBCT images, and neither were these studies justified since measurements were carried out on hard tissue only.
The studies that showed the greatest limitations insofar as the variety of measurements is concerned were those by Berco et al., Brown et al. and Stratemann et al.17,30,31, which only performed point-to-point linear measurements. This can be
explained by the fact that these studies were conducted with the sole purpose of
analyzing the reliability and reproducibility of the measures. Tests of
reproducibility and reliability of the measures were carried out in other studies with this same objective,8,21,23-25,32 and also in some studies where new cephalometric
analyses were proposed.21,25,32 Studies that fail to perform such tests8,23 lose
credibility as a proposed analysis since it is an important step to validate the use of any given measure.36
Cheung et al.25 published the first three-dimensional analysis using the
standards prevalent in the Chinese population, and contended that the findings be used as a benchmark in evaluating morphological malformations, and the results of orthognathic surgery or orthodontic treatment in young Chinese adults. Bayome et al.23 presented an analysis using the standards of the Korean population and
compared some of their data with those of Cheung et al.,25 showing that ethnic
differences do exist, and proposing that studies be conducted with standards of other populations.
The work by Wong21 is based on the analysis of McNamara3, the latter having
been established as a two-dimensional analysis. CBCT, however, made it possible to relate the maxilla, the mandible, the skull base and the teeth in the three planes of space. In that study the author also uses a sample of Chinese subjects, thereby limiting results to a particular ethnic group.
The three-dimensional cephalometric analysis proposed by Cho8 features the
largest number of measurements compared to other studies, most of which were in the transverse direction since according to the authors, this direction is the most favorable plane when using three-dimensional images. In the transverse direction, the measurements of dental relationships using the frontal and oblique planes of reference - as described by the author - tend to prevail. A down side of the study is its sample size, which had only one female individual. The author however agrees that this is only an initial set of measurements for a new 3D cephalometric analysis, and that a larger sample of individuals is bound to yield more useful standards.
In compiling the measurements that are repeated in the 10 studies, it was observed that most of them are already widely applied in two-dimensional analysis (Table IV). Those measures that can only be performed three-dimensionally, i.e., points such as the Gonion (Go), which are assessed separately on the left and right sides, highlight a key advantage of 3D analysis, since in traditional two-dimensional images these structures are superimposed on the cephalometric radiograph.
Also in Table IV, it can be noted that the only direction which includes the measuring of teeth is in the anteroposterior direction, linking the upper incisors to the palatal plane, and the mandibular incisor to the mandibular plane. Only five transverse measures were repeated which assessed the linear distance between the orbits, Gonions (Go), condyles, fronto-zygomatic sutures and foramina mentalis. None of the measures related tooth position with the other structures.
Some of the studies that were excluded because they failed to provide measurements in the three planes of space26,27,40,41 performed only transverse
measures, but none of them is presented as a proposal for a new frontal analysis. Two of these40,41 compare the measurements of conventional posteroanterior
cephalometric tracings with CBCT images.
Among the remaining measures of the studies, i.e., those that do not repeat themselves, some can only be performed on three-dimensional images. Some authors present, each in their own way, planes that were created three-dimensionally to perform linear and angular measurements, particularly Cheung et al.25 and Cho,8
who describe 20 and 15 planes, respectively.
Studies that provide analysis proposals comprising a larger number of individuals in different ethnic groups and are at the same time easy to apply in the clinical setting are necessary if one is to create a comprehensive, clinically feasible three-dimensional cephalometric analysis.
CONCLUSIONS
A systematic search performed on the internet yielded different three-dimensional analysis. A wide diversity of studies was found in terms of the number of measures used, analysis goals, anatomical structures and landmarks. Moreover, certain measurements were repeated across different studies, which seems to point to a tendency to build a new, standardized 3D analysis.
Most analyses continue to use traditional measurements used in 2D methods, with the addition of bilateral and transverse measures that appear to benefit the diagnosis of asymmetries. No measurements were applied to soft tissue (hard tissue only).
Further work is warranted in order to standardize three-dimensional cephalometric measurements, and create baseline standards that are easily applied in the clinical setting.
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4 - CONCLUSÃO
Diferentes análises tridimensionais foram encontradas a partir da busca sistemática. Houve grande variação entre os estudos quanto ao número de medidas utilizadas, objetivos da análise, estruturas anatômicas contempladas e pontos de referência. Por outro lado, observou-se a repetição de algumas medidas em diferentes estudos, o que parece indicar uma tendência para a construção de novas análises 3D.
A base das análises continua sendo medidas tradicionais dos métodos 2D, com o acréscimo de medidas bilaterais e transversais, que parecem beneficiar o diagnóstico de assimetrias. Não houve medidas em tecidos moles, apenas em tecidos duros.
Futuros trabalhos devem ser desenvolvidos com o objetivo de padronizar medidas cefalométricas tridimensionais e criar normas de referência que sejam de fácil aplicabilidade para uso clínico.
ANEXOS Anexo A
Bayome et al. 2013 Berco et al. 2009
Brown et al.
2009 Cheung et al. 2011 Cho HJ. 2009
SNA SNB ANB S NPg angle Facial Angle A to N-Pg Pg to NB Angle of convexity Maxillary length Mandibular body length Ramal a-p inclination Condylar a-p inclination Anterior facial heigth Upper facial heigth Lower facial heigth Maxillary heigth Ramal length Condylar heigth Y-axis
Gonial angle Upper facial width
Anterior maxillary basal width
Posterior maxillary basal width Me angle Me deviation angle Me to midsagittal Ramal mediolateral inclination Go to midsagittal Co to midsagittal Condylar width
Maxillary basal curve length Mandibular basal curve length
MBC angle
Anterior mandibular basal length
Posterior mandibular basal length N-A Point N-B Point N-Pog N-Me A-B A-Pog A-Me B-Pog B-Me Po-Go Co-Go AG-AG Or R-Or L Go R-Go L Po R-Po L Co R-Co L N-Or R N-Or L Or R-A Or R-Pog Or L-A Or L-Pog Co R-Go L Co L-Go R Ba-S’ Or L-Po L Na-Me Co-Go Co-Go Z-Ag Z-Ag Na-ANS ANS-PNS Na-A Na-B Go-Go Mf-Mf Mo-Mo Za-Za NC-NC Z-Z J-J S-N Cg-ANS N-A ANS-Mn A-Gn Cg-Mn N-Gn ANS-U1T L1T-Mn Z plane/MSP Z-MSP ZA-MSP Ag-MSP Gb-sn/sn-pog N-Pog/FH 0 meridian — sn 0 meridian –pog SNA NA/FH IOF-SOMP IOM-SOMP Or-SOMP LPA-SOMP J-MSP LPA-MSP U1T-ANS SNB Go-Mn Ag-Mn Co-Mn N-B-Pog Co-MSP Ag-MSP Ag plane/MSP Mn-MSP L1T-MP Co-Ag Co-FH Sig-FH FH-MP SN-MP Go-Mn/SN S-Gn/FH AgPlane/MSP ANB PP/MP UD/SN U1/SN U1/PP U1-MSP L1/MP L1-MSP OP/FH U.OP/FH U1/L1 OB OJ OP/MSP A(y) B(y) B(y)–A(y) SNA SNB ANB Wits appraisal Pog(y)
Facial line angle (FH-NPog) MxL (ANS-PNS) R MdL (R condylar point-Pog) L MdL (L condylar point-Pog) R MdBL (R Go-Pog) L MdBL (L Go-Pog) R TFP(z) L TFP(z) R Or(z) L Or(z) ANS(z) PNS(z) R MxBP(z) L MxBP(z) MxS line angle Me(z) R Go(z) L Go(z) R MdS line angle L MdS line angle R MdRH L MdRH R GA L GA LFH (ANS-Me) R FZP(x) L FZP(x) CBW (R FZP−L FZP) R TFP(x) L TFP(x) ITFPW ANS(x) PNS(x) R MxBP(x) L MxBP(x) MxBW (R MxBP−L MxBP) MxF line angle Pog(x) R Go(x) L Go(x) MdBW (R Go−L Go) MdF line angle MxMdF line angle R U1SI L U1SI R U1SP L U1SP R L1SI R U3SP L U3SP R L3SI L L3SI R L3SP L L3SP R U6SI L U6SI R U6SP L U6SP R L6SI L L6SI R L6SP L L6SP R U1VD L U1VD R U6VD L U6VD R L1VD L L1VD R L6VD L L6VD MxFO line angle MdFO line angle MxSO line angle
MdSO line angle R U1FI L U1FI R U1FP L U1FP R L1FI L L1FI R L1FP L L1FP R U3FI L U3FI R U3FP L U3FP R L3FI L L3FI R L3FP L L3FP U3CW U3RW L3CW L3RW R U6FI L U6FI R U6FP L U6FP U6CW U6RW R L6FI L L6FI R L6FP L L6FP L L1SI R L1SP L L1SP R U3SI L U3SI L6CW L6RW 29
ANEXOS
Anexo A (Continuação) Moreira et al.
2009 Sanders et al. 2010 Stratemann et al. 2008 Wong et al. 2011 Zamora et al. 2013
A-Pg Co-A Co-Pg ANS-PNS5 ANS-Me ANS-N ANS-A N-A N-B N-Me N-Pg Po-Or Zm-Zm B-Me Ba-N N/A/Pg G/ANS/Pg N/ANS/Me N/Me/Go Co/Go/Me N/A/B
The difference of Md6(z) and Mx6(z) The difference of Mx1(x) and Md1(x) Mx1(y) minus Md1(y)
Mx1(z) minus Md1(z) Distance (z) between Go-Md6 Mx6-Mx1 Md6-Mx1 ANS-PNS/sagittal plane CdS-Pg CdS-Go Go-Pg CdS/Go/Pg Go-Pg/Frankfort horizontal CdL/Go/sagittal plane Md1-Me/sagittal plane CdL-CdM CdA-CdP CdS-GlS CdL-CdM/coronal plane CdL-CdM/axial plane Tub–GPF GPF–PNS (IS) Tub–PNS Or–Tub IOF–Tub Or–IOF IOF–U3 IOF–PR PR–ANS PR–Pr PR–U3 IOF–A IOF–Pr L3–L6 L6–R1 R1–Cor Cor–R3 R3–LatConPol R3–MedConPol (IS) R3–Co Co–LatConPol Co–MedConPol LatConPol–R2 MedConPol–R2 R3–MnFor MnFor–R1 MnFor–R2 MnFor–R4 MnFor–Go MnFor–Cor MnFor–Co Co–R2 R2–Go Go–R4 R4–Me Go–Me Go–Gn Id–L3 Mf–L3 Mf–L6 Mf–Id Mf–B Mf–Pg Mf–Gn Mf–Me U3 Tub PR Or IOF L3 L6 R1 Cor R3 LatConPol MedConPol (IS) Co MnFor (IS) R2 Go R4 Mf ANS–A A–Pr ANS–Pr ANS–PNS Me–Gn Gn–Pg Pg–Id B–Id Pg–B NA-P perpendicular SNA Cd(L)-Gn Cd(R)-Gn Cd(L)-A Cd(R)-A MxMD-DF ANS-Me MD/P left (L) MD/P right (R) FA/A left (L) FA/A right (R) Pg-N Ui-A Li-APg Gl-Me CdR-CdL CdR-Me CdL-Me FzR-Me FzL-Me FzR-FzL Na-GoR Na-GoL GoR-GoL DB-Me DB-GoR DB-GoL Me-GoR Me-GoL KrR-CdR KrL-CdL KrR-GoR KrL-GoL CdR-GoR CdL-GoL CdR/Me/CdL FzR/Me/FzL GoR/N/GoL CdR/KrR/GoR DB/Me/GoR DB/Me/GoL 30
ANEXO
Medida Definição
S Sela: centro da sela túrcica
N Násio: ponto localizado na sutura fronto-nasal A Ponto A: maior concavidade na linha média maxilar B Ponto B: maior concavidade na linha media mandibular ANS Espinha nasal anterior
PNS Espinha nasal posterior
Pg Pogônio: ponto mais anterior no centro da sínfise mandibular Or Orbita: ponto mais inferior na borda inferior da órbita
Po Pório: ponto mais superior do bordo superior do meato auditivo externo FH Plano horizontal de Frankfurt
Co Ponto mais superior no centro do côndilo
Go Gônio: maior convexidade do processo angular no centro médio-lateral Me Mento: ponto mais inferior e central da sínfise mandibular
Gn Gnátio: ponto na linha média, no limite anterior da sínfise mandibular,entre Me e Pg MP Plano mandibular
PP Plano palatal
Z Ponto na margem medial da borda orbital na sutura fronto-zigomática
Mf Forame mentoniano
Cg Crista galli: ponto mais alto e central da apófise crista galli
Anexo B
