Influence of clinical and demographic factors on the oral health-related quality of life of patients with cleft lip and palate undergoing orthodontic treatment: a systematic review and meta-analysis.

OBJECTIVE: The purpose of this study was to evaluate the influence of orthodontic treatment on the oral health-related quality of life (OHRQoL) of patients with cleft lip and palate. SEARCH METHODS: Electronic searches were conducted in Pubmed, Scopus, Web of Science, Cochrane Library, VHL, and OpenGrey databases, completed in January 2021. SELECTION CRITERIA: Cross-sectional and longitudinal observational studies that presented an assessment of OHRQoL in cleft patients undergoing orthodontic treatment were included, according to PRISMA guidelines. Contacts via email were made with authors, to clarify inaccuracies or request additional data. DATA COLLECTION AND ANALYSIS: The entire process was accomplished by two authors, in case of disagreement, a third author mediated the discussion until there was a consensus. Risk assessment was performed by the Fowkes and Fulton qualifier, and the quality of evidence, assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tool. A meta-analysis was performed considering the domains combined into three large groups (physical, psychological, and social). The questionnaires were standardized as to the scores and their direction. RESULTS: A total of 3822 studies were retrieved. After excluding duplicates, the titles and abstracts of the remaining articles were analysed. Twenty-eight articles were read in full; 13 met the eligibility criteria; 12 articles showed sufficient methodological quality and 7 were included in the quantitative assessment. The included studies were published between 2011 and 2019. The samples comprised 19 to 183 patients of both sexes. GRADE showed low evidence when compared to the control group, sexes, age, and types of cleft and very low evidence among longitudinal articles. CONCLUSIONS: The OHRQoL is lower in orthodontic patients with cleft than in those without. The OHRQoL of patients with cleft undergoing orthodontic treatment is not influenced by gender or age group, considering children and adolescents, but it is influenced by the type of cleft. The OHRQoL of patients with CLP does not undergo significant changes during orthodontic treatment. LIMITATIONS: The variety of instruments for measuring OHRQoL rendered meta-analysis difficult. REGISTRATION: PROSPERO database number CRD42017054764.

Hyperextension of the head versus cervical vertebrae morphology in mouth and nasal breathers: a preliminary study

Objective: This study aimed to compare through cone-beam computed tomography (CBCT) the morphology of the cervical vertebrae atlas (C1) and axis (C2) in mouth breathers (MB) and nose breathers (NB), correlating them with the head and neck postures of the two groups. Materials and Methods: CBCT images of 36 subjects aged 11 to 22 years were evaluated using the InVivo Dental 5.1 (Anatomage, San Jose, California) software. The following measurements were used to assess C1 and C2 morphology: posterior height, anterior height, length, and volume. The craniocervical angle (NSL/OPT) was used to evaluate head posture concerning the neck. Results: The posterior height, length, and volume of C1 and C2 were lower in the MB group, but only the posterior size was significantly shorter than the NB group (C1, p=0.01 / C2, =0.05). Mouth breathers also showed a considerably higher craniocervical angle (p=0.04). Spearman test showed a significant positive correlation between C1 and C2 length and craniocervical angle (C1, =0.629, p=0.005 / C2, =0.665, p=0.003). Conclusion: The mouth breathers showed an increased craniocervical angle and decreased posterior height of the C1 vertebra concerning nasal breathers. The hyperextension of the head present is positively correlated with the length of the vertebra.

Objetivo: Este estudo teve como objetivo comparar por meio da tomografia computadorizada de feixe cônico (TCFC) a morfologia do atlas das vértebras cervicais (C1) e do eixo (C2) em respiradores orais (MB) e nasais (RN), correlacionando-os com a cabeça e posturas do pescoço dos dois grupos. Materiais e Métodos: Imagens de CBCT de 36 indivíduos com idades entre 11 e 22 anos foram avaliadas usando o software InVivo Dental 5.1 (Anatomage, San Jose, Califórnia). As seguintes medidas foram usadas para avaliar a morfologia de C1 e C2: altura posterior, altura anterior, comprimento e volume. O ângulo craniocervical (NSL/OPT) foi utilizado para avaliar a postura da cabeça em relação ao pescoço. Resultados: A altura posterior, comprimento e volume de C1 e C2 foram menores no grupo MB, mas apenas o tamanho posterior foi significativamente menor que o grupo RN (C1, p=0,01 / C2, =0,05). Os respiradores orais também apresentaram um ângulo craniocervical consideravelmente maior (p=0,04). O teste de Spearman mostrou correlação positiva significativa entre comprimento de C1 e C2 e ângulo craniocervical (C1, =0,629, p=0,005 / C2, =0,665, p=0,003). Conclusão: Os respiradores orais apresentaram aumento do ângulo craniocervical e diminuição da altura posterior da vértebra C1 em relação aos respiradores nasais. A hiperextensão da cabeça presente está positivamente correlacionada com o comprimento da vértebra.

Effects of the cervical headgear in growing Angle Class II malocclusion patients: a prospective study.

OBJECTIVE: Evaluate dental and skeletal changes resulting from the exclusive use of the cervical headgear for 15 ± 4 months in the treatment of patients with Class II division 1 malocclusion. METHODS: Differences between the beginning (T1) and immediately after the end of the therapy (T2) with the cervical headgear in growing patients (Experimental Group, EG, n = 23) were examined and compared, during compatible periods, with those presented by a group of untreated individuals (Control Group, CG, n =22) with similar malocclusions and chronological age. The cephalometric variables evaluated were: ANB, GoGn.SN, AO-BO, S'-ANS, S'-A, S'-B, S'-Pog and S'-U6 (maxillary first molar). The Shapiro-Wilk and Levene tests were used to evaluate the results. RESULTS: Significant differences were found relative to the ANB, S'-U6, AO-BO, S'-ANS, S'-A, S'-B and S'-Pog variables between T1 and T2 when comparing both groups. No statistically significant variation was found regarding the GoGn.SN angle. CONCLUSIONS: The use of cervical headgear promoted distal movement of the maxillary first molars and restricted the anterior displacement of the maxilla, without significantly affecting the GoGn.SN angle.

Is mouth-breathing related to alterations in facial soft tissues?

Objective: To compare the facial soft tissues of nasal breathers (NB) and mouthbreathers (MB) using cone-beam computed tomography (CBCT).Methods: This was a comparative study of four angular and eight linearcephalometric variables obtained from the facial soft tissues of 43 young menand women aged between 11 and 24 years. Subjects had tomographic examinationprior to the orthodontic treatment and were previously divided into two groupsby an otolaryngologist according to the respiratory pattern of nasal or mouthbreathing. The selection was made in accordance with the results of: clinicalexamination, rhinoscopy, and nasal endoscopy. The data obtained from thesoftware InVivo Dental 5.3 (Anatomage - San Jose, California) was evaluated bycomparing values measured between MB and NB groups. Results: There weresignificant differences between groups for variables, "nasolabial angle", inclinationof upper central incisor" and "convexity of the facial soft tissues". Conclusion:Adolescent and young adult mouth breathers present an open nasolabial angledue to the retroinclination of their upper incisors. In addition to greater convexityof the facial soft tissues.

Objetivo: Comparar os tecidos moles faciais de respiradores nasais (RN) e bucais(RB), utilizando imagens de tomografia computadorizada de feixe cônico (TCFC).Métodos: Foi realizado um estudo comparativo composto por quatro variáveiscefalométricas angulares e oito lineares, obtidas de tecidos moles faciais deindivíduos RN e RB, em uma amostra composta por 43 indivíduos jovens deambos os sexos, com idades entre 11 e 24 anos, submetidos ao exame tomográficoanteriormente ao tratamento ortodôntico. Os indivíduos foram previamentedivididos em dois grupos por um otorrinolaringologista, de acordo com o padrãorespiratório. O diagnóstico da respiração bucal foi feito em conformidade comos resultados de exames específicos: exame clínico, rinoscopia e endoscopia nasal.Os dados obtidos a partir do software InVivo 5.3 Dental (Anatomage - San Jose,Califórnia) foram avaliados através da comparação dos valores das mediçõesdas variáveis dos grupos RN e RB, além da comparação das diferenças entreesses valores. Resultados: Houve diferenças estatisticamente significativas entreos grupos com relação às variáveis, "ângulo nasolabial", "inclinação do incisivocentral superior" e "convexidade dos tegumentos faciais". Conclusão: Osrespiradores bucais adolescentes e adultos jovens apresentam ângulo nasolabialmais aberto, devido à maior inclinação lingual do longo eixo dos incisivossuperiores, além de maior convexidade dos tecidos moles faciais.

Do Laypeople, students and orthodontists have similar concepts regarding facial aesthetics?

Introduction: A harmonious profile is one of the objectives of the orthodontic planning. It is as important as to establish functional occlusion, since facial aesthetics is not only a concern for the orthodontist, but also for individuals who want to undergo orthodontic treatment. Objective: To analyze the facial profile considered pleasant for the white Brazilians, verify their common characteristics and, thus, guide the orthodontists in relation to facial aesthetics. Methods: Facial profile photographs from 100 adult white Brazilians were analyzed and evaluated by 15 lay people, 15 orthodontic students and 15 orthodontists. Tracings and cephalometric analysis were made from the best rated facial profiles, including linear and angular measurements and facial proportions. Results: Considerable similarities were found between the simulated profiles which were shaped according to each group's outcome. These results can be attributed to the influence of the media that, somehow, contributed to homogenize the population's standards related to facial esthetics. Conclusion: Despite the great similarity in relation to the aesthetic concepts showed by the evaluators, lay people seem to prefer more concave profiles when compared with the other groups.

Introdução: O ortodontista não se preocupa apenas em estabelecer a oclusão funcional, mas também em proporcionar ao paciente um perfil harmonioso, uma das principais motivações daqueles que procuram por tratamento. Objetivo: Analisar os perfis faciais considerados agradáveis de indivíduos leucodermas brasileiros, buscando verificar suas características em comum e, assim, orientar os ortodontistas quanto aos objetivos finais do tratamento ortodôntico em relação à estética facial. Métodos: Fotografias de perfil de 100 indivíduos brasileiros leucodermas adultos foram avaliadas por 15 leigos, 15 estudantes de ortodontia e 15 ortodontistas. Foram realizados traçados e análises cefalométricas dos perfis que obtiveram as melhores avaliações, incluindo medidas lineares, angulares e de proporções faciais. Resultados: Verificou-se uma considerável semelhança entre as simulações dos perfis faciais construídos de acordo com o resultado da avaliação de cada grupo de julgadores. Este resultado foi atribuído à influência da mídia, que de alguma forma contribuiu para homogeneizar os padrões de estética facial. Conclusão: Apesar da grande semelhança em relação aos conceitos estéticos apresentados pelos avaliadores, os leigos parecem preferir perfis mais côncavos quando comparados aos demais.

Agreement in the determination of preformed wire shape templates on plaster models and customized digital arch form diagrams on digital models.

INTRODUCTION: The aim of this study was to verify the accuracy of preformed wire shape templates on plaster models and those of customized digital arch form diagrams on digital models. METHODS: Twenty pairs of dental plaster models were randomly selected from the archives of the Department of Orthodontics of Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. All plaster model samples were scanned in a plaster model scanner to create the respective digital models. Three examiners defined the arch form on the mandibular arch of these models by selecting the ideal preformed wire shape template on each plaster model or by making a customized digital arch form on the digital models using a digital arch form customization tool. These 2 arch forms were superimposed by the best-fit method. The greatest differences in the 6 regions on the superimposed arches were evaluated. Each examiner presented a descriptive analysis with the means, standard deviation, and minimum and maximum intervals of the differences on the superimpositions. Intraclass correlation coefficient and paired t tests were used to evaluate the accuracy of the superimpositions. RESULTS: Among the 6 regions analyzed in the superimpositions, the largest differences in the anterior and premolar regions were considered clinically insignificant, whereas the largest differences in the right molar region, especially the second molar area, were considered clinically significant by all 3 examiners. The intraclass correlation coefficients showed a weak correlation in the premolar region and moderate correlations in the anterior and molar regions. The paired t test showed statistically significant differences in the left anterior and premolar regions. CONCLUSIONS: The superimpositions between the arch forms on plaster and digital models were considered accurate, and the differences were not clinically significant, with the exception of the second molar area. Despite the favorable results, the requirement of correcting some software problems may hamper the transition from plaster to digital models.

Clinical recognition of mouth breathers by orthodontists: A preliminary study.

INTRODUCTION: A routine diagnosis of a patient's breathing status performed by an orthodontist normally includes visual assessment, medical history, clinical examination of habitual lip posture, size and shape of the nostrils, reflex control of the alar muscle and respiratory tests, and the dental mirror test. The objective of this study was to test the recognition of mouth breathers in young persons by an orthodontist and agreement with an otolaryngologist's reference diagnosis when routine assessments were carried out. METHODS: Three independent and blind evaluations were conducted on the same day by 2 orthodontists independently (anamnesis and breathing tests, respectively) and an otolaryngologist (rhinoscopy, nasal endoscopy, and visual assessment). The weighted kappa coefficient was used to test intraexaminer and interexaminer agreement. The frequencies of answers and findings were reported for each breathing status. RESULTS: Fifty-five volunteers composed the sample of this study; 20 participants were nasal breathers, and 35 participants were classified as mouth breathers (and subdivided into mouth breathers with airway obstruction and mouth breathers by habit) by the otolaryngologist. The weighted kappa coefficient showed poor interrater agreement for most comparisons. CONCLUSIONS: Recognition of mouth breathing in young persons by orthodontists is poor.

Are there differences between comparison methods used to evaluate the accuracy and reliability of digital models?

OBJECTIVES: The accuracy and reliability of plaster models and digital models acquired with two different surface laser scanners were tested by means of three methods: measurement with calipers, digital measurement with proper software and superimposition of the digital models. METHODS: Thirty plaster models with permanent dentition that met the inclusion criteria were selected and scanned with two laser scanners (R700 and Xcad). Three examiners measured distances on plaster models with a digital caliper and on digital models using Ortho Analyzer software. The digital models were also compared by means of superimposition of the models using the Geomagic Qualify software. The intra and inter-examiner reliability of the measurements were evaluated using the ICC. Paired t test was used to test the accuracy of the measurements on digital and plaster models. RESULTS: The measurements on plaster and digital models acquired by two different scanners showed high values for the ICC. Although statistically significant differences between the measurements on plaster and digital models have been found, these discrepancies were not considered clinically relevant. The superimposition method with Geomagic Qualify software showed that the two digital models were not significantly different. CONCLUSIONS: Digital models created from scanned plaster models using the R700 or Xcad scanners were clinically accurate according to the two methods of comparison used.

Are there differences between comparison methods used to evaluate the accuracy and reliability of digital models?

ABSTRACT Objectives: The accuracy and reliability of plaster models and digital models acquired with two different surface laser scanners were tested by means of three methods: measurement with calipers, digital measurement with proper software and superimposition of the digital models. Methods: Thirty plaster models with permanent dentition that met the inclusion criteria were selected and scanned with two laser scanners (R700 and Xcad). Three examiners measured distances on plaster models with a digital caliper and on digital models using Ortho Analyzer software. The digital models were also compared by means of superimposition of the models using the Geomagic Qualify software. The intra and inter-examiner reliability of the measurements were evaluated using the ICC. Paired t test was used to test the accuracy of the measurements on digital and plaster models. Results: The measurements on plaster and digital models acquired by two different scanners showed high values for the ICC. Although statistically significant differences between the measurements on plaster and digital models have been found, these discrepancies were not considered clinically relevant. The superimposition method with Geomagic Qualify software showed that the two digital models were not significantly different. Conclusions: Digital models created from scanned plaster models using the R700 or Xcad scanners were clinically accurate according to the two methods of comparison used.

RESUMO Objetivos: a acurácia e a confiabilidade de modelos de gesso e modelos digitais adquiridos por dois diferentes scanners de superfície a laser foram testadas com três métodos: medição com paquímetro, medição com programa específico e sobreposição de modelos digitais. Métodos: trinta modelos de gesso com dentição permanente que preencheram os critérios de inclusão predeterminados foram selecionados e escaneados com dois diferentes scanners a laser (R700 e Xcad). Três examinadores mediram distâncias selecionadas nos modelos de gesso usando um paquímetro digital e, nos modelos digitais, usando o programa Ortho Analyzer. Os modelos digitais também foram comparados por sobreposição de modelos, com o programa Geomagic Qualify. A confiabilidade intra e interexaminadores das medições foi avaliada por meio do coeficiente de correlação intraclasse (ICC). O teste t pareado foi utilizado para avaliar a acurácia das medições nos modelos de gesso e digitais. Resultados: as medições nos modelos de gesso e nos modelos digitais escaneados pelos dois diferentes scanners apresentaram valores elevados para o ICC. As diferenças estatisticamente significativas encontradas entre as medições nos modelos de gesso e nos modelos digitais não foram consideradas clinicamente relevantes. O método de sobreposição de modelos com o programa Geomagic Qualify demonstrou que os dois tipos de modelos digitais não foram significativamente diferentes. Conclusões: os modelos digitais criados a partir do escaneamento dos modelos de gesso com os scanners R700 e Xcad foram clinicamente precisos, de acordo com os dois métodos de comparação utilizados.

Acurácia de modelos ortodônticos por escaneamento a laser, luz estruturada e tomografia computadorizada / Accuracy of orthodontic models scanned by laser, structured light, and computed tomography

Introdução: com a crescente utilização dos modelos digitais em Ortodontia, aumenta também a necessidade de se conhecer as opções disponíveis para sua obtenção. Atualmente, a alternativa mais utilizada é o escaneamento de modelos de gesso, que pode ser realizado em scanners a laser, por luz estruturada ou por tomografia computadorizada. O objetivo deste trabalho foi avaliar, através de uma análise por sobreposição de modelos digitais, a acurácia dos modelos digitais gerados por estes três métodos de escaneamento e a influência de dois diferentes níveis de resolução de escaneamento. Material e métodos: 30 pares de modelos de gesso foram escaneados utilizando as três tecnologias. O escaneamento por luz estruturada foi realizado com duas configurações do nível de resolução: máxima e padrão. Os modelos digitais gerados foram sobrepostos e as diferenças entre as superfícies foram calculadas. Mapas de cores foram utilizados para evidenciar as discrepâncias entre os modelos. Resultados: para todos os parâmetros avaliados, foram obtidas diferenças estatisticamente significantes. As diferenças entre os modelos escaneados a laser e por luz estruturada foram menores, o que sugere maior similaridade entre eles. Conclusão: as diferenças encontradas entre os modelos digitais obtidos pelas três tecnologias de escaneamento estudadas foram estatisticamente significantes. No entanto, por serem muito pequenas quantitativamente, não foram consideradas clinicamente significantes. Não houve diferença entre os dois níveis de resolução estudados, portanto, os três métodos de escaneamento avaliados possuem uma acurácia clinicamente aceitável para ser utilizado em Ortodontia.

Introduction: the increasing use of digital models in orthodontics demands knowledge of the available options for their acquisition. Currently, the most used option is the plaster model scanning, which can be made by laser, structured light and computed tomography scanners. The aim of this study was to evaluate, by a model superimposition analysis, the accuracy of digital models acquired by these three scanning methods and the influence of two different resolution levels of scanning. Methods: thirty pairs of plaster models were scanned using three different scanning technologies: laser, structured light and computed tomography. The structured light scanning was performed using two different resolution levels: maximum and standard. The respective digital models were superimposed and their mean differences were compared using color maps by Geomagic Qualify software. Results: for all parameters studied, statistically significant differences were found. Lower differences were presented between models scanned by laser and structured light techniques, which suggests a higher similarity between them. Conclusion: the differences found between digital models obtained by the three scanning technologies were statistically significant. However, they were quantitatively very small, which was considered clinically insignificant. There was no difference between the two resolution levels of scanning studied. Therefore the three scanning methods studied presented accuracy clinically acceptable to be used in orthodontics.

Digital orthodontic radiographic set versus cone-beam computed tomography: an evaluation of the effective dose.

OBJECTIVE: The aim of this study was to compare the equivalent and effective doses of different digital radiographic methods (panoramic, lateral cephalometric and periapical) with cone-beam computed tomography (CBCT). METHODS: Precalibrated thermoluminescent dosimeters were placed at 24 locations in an anthropomorphic phantom (Alderson Rando Phantom, Alderson Research Laboratories, New York, NY, USA), representing a medium sized adult. The following devices were tested: Heliodent Plus (Sirona Dental Systems, Bernsheim, Germany), Orthophos XG 5 (Sirona Dental Systems, Bernsheim, Germany) and i-CAT (Imaging Sciences International, Hatfield, PA, USA). The equivalent doses and effective doses were calculated considering the recommendations of the International Commission of Radiological Protection (ICRP) issued in 1990 and 2007. RESULTS: Although the effective dose of the radiographic set corresponded to 17.5% (ICRP 1990) and 47.2% (ICRP 2007) of the CBCT dose, the equivalent doses of skin, bone surface and muscle obtained by the radiographic set were higher when compared to CBCT. However, in some areas, the radiation produced by the orthodontic set was higher due to the complete periapical examination. CONCLUSION: Considering the optimization principle of radiation protection, i-CAT tomography should be used only in specific and justified circumstances. Additionally, following the ALARA principle, single periapical radiographies covering restricted areas are more suitable than the complete periapical examination.

Digital orthodontic radiographic set versus cone-beam computed tomography: an evaluation of the effective dose

ABSTRACT Objective: The aim of this study was to compare the equivalent and effective doses of different digital radiographic methods (panoramic, lateral cephalometric and periapical) with cone-beam computed tomography (CBCT). Methods: Precalibrated thermoluminescent dosimeters were placed at 24 locations in an anthropomorphic phantom (Alderson Rando Phantom, Alderson Research Laboratories, New York, NY, USA), representing a medium sized adult. The following devices were tested: Heliodent Plus (Sirona Dental Systems, Bernsheim, Germany), Orthophos XG 5 (Sirona Dental Systems, Bernsheim, Germany) and i-CAT (Imaging Sciences International, Hatfield, PA, USA). The equivalent doses and effective doses were calculated considering the recommendations of the International Commission of Radiological Protection (ICRP) issued in 1990 and 2007. Results: Although the effective dose of the radiographic set corresponded to 17.5% (ICRP 1990) and 47.2% (ICRP 2007) of the CBCT dose, the equivalent doses of skin, bone surface and muscle obtained by the radiographic set were higher when compared to CBCT. However, in some areas, the radiation produced by the orthodontic set was higher due to the complete periapical examination. Conclusion: Considering the optimization principle of radiation protection, i-CAT tomography should be used only in specific and justified circumstances. Additionally, following the ALARA principle, single periapical radiographies covering restricted areas are more suitable than the complete periapical examination.

RESUMO Objetivo: o objetivo deste estudo foi comparar as doses equivalentes e efetivas absorvidas pelo mesmo receptor, quando exposto a diferentes exames radiográficos digitais (panorâmica, telerradiografia lateral e periapicais) e à tomografia computadorizada de feixe cônico (TCFC). Métodos: dosímetros termoluminescentes pré-calibrados foram colocados em 24 locais em um phantom antropomórfico (Alderson Rando Phantom, Laboratórios de Pesquisas de Alderson, New York, NY, EUA), o que representa um adulto de tamanho médio. Os seguintes equipamentos foram avaliados: Heliodent Plus (Sirona Dental Systems, Bernsheim, Alemanha), Orthophos XG 5 (Sirona Dental Systems, Bernsheim, Alemanha) e i-CAT (Imaging Sciences International, Hatfield, PA, EUA). As doses equivalentes e as doses efetivas foram calculadas tendo-se em conta as recomendações da Comissão Internacional de Proteção Radiológica (International Commission on Radiological Protection, ICRP), publicadas em 1990 e 2007. Resultados: embora a dose eficaz do set radiográfico tenha correspondido a 17,5% (ICRP 1990) e 47,2% (ICRP 2007) da dose da TCFC, as doses equivalentes na pele e superfícies ósseas e musculares desse set foram maiores, quando comparadas às da TCFC. Em algumas áreas, a radiação produzida pelo set de radiografias foi maior, devido à radiação do exame periapical completo. Conclusão: considerando-se o princípio da otimização da proteção radiológica, a tomografia computadorizada adquirida no tomógrafo i-CAT deve ser usada apenas em circunstâncias específicas e justificadas. Além disso, seguindo o princípio ALARA, radiografias periapicais unitárias de áreas pré-selecionadas são mais apropriadas do que o exame periapical completo.

Severe root resorption resulting from orthodontic treatment: prevalence and risk factors.

OBJECTIVE: To assess the prevalence of severe external root resorption and its potential risk factors resulting from orthodontic treatment. METHODS: A randomly selected sample was used. It comprised conventional periapical radiographs taken in the same radiology center for maxillary and mandibular incisors before and after active orthodontic treatment of 129 patients, males and females, treated by means of the Standard Edgewise technique. Two examiners measured and defined root resorption according to the index proposed by Levander et al. The degree of external apical root resorption was registered defining resorption in four degrees of severity. To assess intra and inter-rater reproducibility, kappa coefficient was used. Chi-square test was used to assess the relationship between the amount of root resorption and patient's sex, dental arch (maxillary or mandibular), treatment with or without extractions, treatment duration, root apex stage (open or closed), root shape, as well as overjet and overbite at treatment onset. RESULTS: Maxillary central incisors had the highest percentage of severe root resorption, followed by maxillary lateral incisors and mandibular lateral incisors. Out of 959 teeth, 28 (2.9%) presented severe root resorption. The following risk factors were observed: anterior maxillary teeth, overjet greater than or equal to 5 mm at treatment onset, treatment with extractions, prolonged therapy, and degree of apex formation at treatment onset. CONCLUSION: This study showed that care must be taken in orthodontic treatment involving extractions, great retraction of maxillary incisors, prolonged therapy, and/or completely formed apex at orthodontic treatment onset.

Avaliação da acurácia e confiabilidade de modelos digitais por escaneamento do modelo de gesso / Evaluation of the accuracy and reliability of digital models by scanning the plaster cast

Introdução: o objetivo deste estudo foi avaliar a acurácia e a confiabilidade de medições feitas em modelos digitais obtidos com um scanner a laser de superfície (R700; 3Shape, Copenhagen, Dinamarca). Material e métodos: foram selecionados 30 modelos ortodônticos de gesso de dentições permanentes. As medições foram realizadas por três examinadores com um paquímetro digital, diretamente sobre os modelos de gesso, e digitalmente, através do programa Ortho Analyser (3Shape, Copenhagen, Dinamarca), nos modelos digitais. Foram determinadas 62 medidas, incluindo diâmetro e altura dentária, overjet, overbite, distâncias intercanino e intermolar, e relação sagital bilateral. Utilizou-se o teste t pareado para avaliar o erro intraexaminador e a acurácia das medições nos modelos digitais. Avaliou-se a reprodutibilidade entre os examinadores por meio do coeficiente de correlação intraclasse e a confiabilidade pelo teste de Bland e Altman. Resultados: apesar de existirem diferenças estatisticamente significantes entre as medições realizadas entre os modelos de gesso e os digitais, as discrepâncias foram consideradas clinicamente não significantes. Tanto os modelos de gesso quanto os modelos digitais apresentaram altos valores no coeficiente de correlação intraclasse entre os examinadores. Conclusão: os modelos digitais por escaneamento do modelo de gesso, utilizando o scanner R700 e o programa Ortho Analyser, podem ser utilizados com acurácia clinicamente aceitável e uma excelente confiabilidade e reprodutibilidade. Os modelos digitais podem substituir os modelos de gesso com segurança.

Introduction: the aim of this study was to evaluate the accuracy and reliability of measurements made on digital models obtained with a laser scanner surface (R700; 3Shape, Copenhagen, Denmark). Material and methods: thirty orthodontic plaster models of permanent dentition were selected. The measurements were performed by three examiners with a digital caliper directly on the plaster casts and digitally, through Ortho Analyser software (3Shape, Copenhagen, Denmark), in digital models. It was determined sixty two measures, including diameter and tooth height, overjet, overbite, intercanino and intermolar distances and bilateral sagittal relationship. It was used paired t test to assess intra-examiner error and the accuracy of measurements in digital models. It was evaluated the reproducibility between examiners using the intraclass correlation coefficient and reliability by Bland and Altman test. Results: although there were significant differences between the plaster casts and the digital models measurements, the discrepancies were considered clinically insignificant. Plaster casts and digital models showed high values of intraclass correlation coefficient among examiners. Conclusion: digital models by scanning plaster cast using the R700 scanner and Ortho Analyser software can be used with clinically acceptable accuracy and excellent reliability and reproducibility. Digital models can replace the plaster models safely.

Severe root resorption resulting from orthodontic treatment: Prevalence and risk factors

OBJECTIVE: To assess the prevalence of severe external root resorption and its potential risk factors resulting from orthodontic treatment. METHODS: A randomly selected sample was used. It comprised conventional periapical radiographs taken in the same radiology center for maxillary and mandibular incisors before and after active orthodontic treatment of 129 patients, males and females, treated by means of the Standard Edgewise technique. Two examiners measured and defined root resorption according to the index proposed by Levander et al. The degree of external apical root resorption was registered defining resorption in four degrees of severity. To assess intra and inter-rater reproducibility, kappa coefficient was used. Chi-square test was used to assess the relationship between the amount of root resorption and patient's sex, dental arch (maxillary or mandibular), treatment with or without extractions, treatment duration, root apex stage (open or closed), root shape, as well as overjet and overbite at treatment onset. RESULTS: Maxillary central incisors had the highest percentage of severe root resorption, followed by maxillary lateral incisors and mandibular lateral incisors. Out of 959 teeth, 28 (2.9%) presented severe root resorption. The following risk factors were observed: anterior maxillary teeth, overjet greater than or equal to 5 mm at treatment onset, treatment with extractions, prolonged therapy, and degree of apex formation at treatment onset. CONCLUSION: This study showed that care must be taken in orthodontic treatment involving extractions, great retraction of maxillary incisors, prolonged therapy, and/or completely formed apex at orthodontic treatment onset. .

OBJETIVO: avaliar a prevalência de reabsorções radiculares externas severas e identificar prováveis fatores de risco decorrentes do tratamento ortodôntico. MÉTODOS: utilizou-se uma amostra selecionada aleatoriamente, composta de radiografias periapicais de incisivos superiores e inferiores, obtidas no mesmo centro radiológico, de pré- e pós-tratamento ortodôntico ativo, de 129 pacientes, de ambos os sexos, tratados por meio da técnica Edgewise Standard. Dois examinadores mensuraram e definiram a reabsorção radicular de acordo com índice proposto por Levander et al., e o grau de reabsorção foi registrado, definindo a reabsorção em quatro graus de severidade. Para avaliar a reprodutibilidade intra- e interexaminadores, adotou-se o índice de coeficiente kappa ponderado. O teste chi-quadrado (χ2) foi adotado para avaliar a relação entre a quantidade de reabsorção radicular e o sexo dos pacientes, arcada dentária (superior ou inferior), tratamentos com ou sem extrações, duração do tratamento, forma radicular, estágio do ápice radicular (aberto ou fechado), overjet e overbite no início do tratamento. RESULTADOS: os incisivos centrais superiores apresentaram a maior porcentagem de reabsorção radicular severa, seguidos dos incisivos laterais superiores e dos incisivos laterais inferiores. Entre 959 dentes avaliados, 28 (2,9%) apresentaram reabsorção radicular severa. Os fatores de risco relacionados foram: dentes localizados na região anterossuperior, overjet maior ou igual a 5mm ao início do tratamento, tratamentos envolvendo extrações dentárias, tempo prolongado de terapia e formação radicular completa à época do início do tratamento ortodôntico. CONCLUSÃO: o estudo demonstrou que cuidados devem ser tomados em tratamentos ortodônticos envolvendo extrações, com grande retração de incisivos superiores, tratamentos prolongados e/ou ápice radicular completamente formado no início da terapia ortodôntica. .

Evaluation of cephalometric landmark identification on CBCT multiplanar and 3D reconstructions.

OBJECTIVE: To evaluate the reliability of three-dimensional (3D) landmark identification in cone-beam computed tomography (CBCT) using two different visualization techniques. MATERIALS AND METHODS: Twelve CBCT images were randomly selected. Three observers independently repeated three times the identification of 30 landmarks using 3D reconstructions and 28 landmarks using multiplanar views. The values of the coordinates X, Y, and Z of each point were obtained and the intraclass correlation coefficient (ICC) was calculated. RESULTS: The ICC of the 3D visualization was rated >0.90 in 67.76% and 45.56%, and ≤0.45 in 13.33% and 14.46% of the intraobserver and interobserver assessments, respectively. The ICC of the multiplanar visualization was rated >0.90 in 82.16% and 78.56% and ≤0.45 in only 16.7% and 8.33% of the intraobserver and interobserver assessments, respectively. An individual landmark classification was done according to ICC values. CONCLUSIONS: The frequency of highly reliable values was greater for multiplanar than 3D reconstructions. Overall, lower reliability was found for points on the condyle and higher reliability for those on the midsagittal plane. Depending on the anatomic region, the observer must choose the most reliable type of image visualization.

Evaluation of two methods for mixed dentition analysis using the method error

AIM: In order to determine the reliability between two of these methodologically different method, this study evaluated the systematic and random errors of the method proposed by Tanaka and Johnston, which is based on the sum of mandibular permanent incisors, and the Huckaba method, which uses radiographs. METHODS: In a random sample of 28 plaster models of mandibular dental arches belonging to individuals of both genders, aged six to eleven years old, a single investigator performed the measurement of required space, according to the two methods evaluated. After 15 days, the measurements were repeated, and each of them was performed twice in sequence to calculate the repeatability and reproducibility conditions, and the systematic and random errors for each method. RESULTS: The random error of the method proposed by Huckaba was larger in terms of reproducibility (1.53 mm) and repeatability (0.57 mm) compared with the analysis proposed by Tanaka and Johnston (0.20 mm and 0.12 mm, respectively). CONCLUSIONS: The method proposed by Huckaba was proved to be inadequate in relation to reproducibility, with respect to the random error, and should be used with caution to measure the required space in the mandibular arch...

Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations.

OBJECTIVE: To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. MATERIAL AND METHODS: Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brackets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric ligatures (TP Orthodontics) were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M). The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil). The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. RESULTS: Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. CONCLUSION: even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material.

Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations

Objective: To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. Material and Methods: Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brackets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric ligatures (TP Orthodontics) were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M). The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil). The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. Results: Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. Conclusion: even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material. .