Measurement of the bone height of mandibular incisors and canines on computed tomography-Limitations according to bone thickness.

AIM: To verify the correlation between cone beam CT (CBCT) and spiral CT (SCT) images and direct measurement of the bone height and to verify whether bone thickness (BT) influences the accuracy of bone height measurement on CT. SETTING AND SAMPLE: One hundred and fourteen measurements were obtained in 10 dry human mandibles. MATERIALS AND METHODS: The alveolar bone height was measured on volumetric and linear images. RESULTS: Negative, average and significant correlations (-0.622** to -0.489**) were verified between BT and the absolute error. When the alveolar bone thickness was at least 0.6 mm, the mean differences were 0.16 and 0.28 mm on linear images and 0.12 and 0.03 mm on volumetric images for CBCT and SCT. Additionally, these values ranged from -0.46 to 0.79 and -0.32 to 0.88 mm on linear images and from -0.64 to 0.67 and -0.57 to 0.62 mm on volumetric images for CBCT and SCT. When the alveolar bone thickness was less than 0.6 mm, the CT evaluation varied from -1.74 to 5.42 and -1.64 to 5.42 mm on linear images and from -3.70 to 4.28 mm and -3.49 to 4.25 mm on volumetric images for CBCT and SCT. CONCLUSIONS: Spiral CT and CBCT images demonstrate significant correlation with direct measurement for the alveolar bone height. Measurement of the alveolar bone labial and lingual to the mandibular incisors and canines presented higher accuracy when its thickness was greater than 0.6 mm. When the thickness was less than 0.6 mm, bone dehiscence can be diagnosed despite bone being clinically present.

Can lingual spurs alter the oral health-related quality of life during anterior open bite interceptive treatment? A systematic review.

INTRODUCTION: The use of lingual spurs has been described as one efficient option, with great stability of results, but with scarce information of toleration for use in the mixed and permanent dentition phases. OBJECTIVE: The purpose of this study was to assess the impact of lingual spurs on the oral health-related quality of life of children and/or adolescents during anterior open bite treatment. METHODS: The review was recorded in the PROSPERO database. Eight electronic databases and partial gray literature were searched, without restrictions until march 2022. A manual search was also performed in the references of the included articles. Studies assessing the impact of lingual spurs on the oral health-related quality of life were included. Risk of bias was assessed using JBI or ROBINS-I tool, according to the study design. The level of evidence was assessed through GRADE. RESULTS: Five studies met the eligibility criteria. Two non-randomized clinical trials had a serious risk of bias. Of the case-series studies, two had a low risk of bias and the other, a moderate risk of bias. The certainty of the evidence was classified as very low for all the evaluated results. In general, the studies reported an initial negative impact with the use of lingual spurs, however this was transitory in nature. A quantitative analysis was not performed due to the great heterogeneity between the studies. CONCLUSION: Current evidence, although limited, suggests that lingual spurs have an initial transient negative impact during interceptive treatment. Additional well-conducted randomized clinical trials are needed.

World Federation of Orthodontists guidelines for postgraduate orthodontic education.

Advanced dental education programs in orthodontics and dentofacial orthopedics require an extensive and comprehensive evidence-based experience, which must be representative of the current didactic and technical advancements. Over the past 25 years, the World Federation of Orthodontists (WFO) has placed emphasis in the support for the recognized orthodontic specialty training programs in every region of the world. In its early years, the WFO developed general principles for specialty education that culminated in the first comprehensive curriculum recommendations, i.e., the WFO Guidelines for Postgraduate Orthodontic Education, which was published in February 2009. In view of the significant changes in the specialty of orthodontics, the WFO has revised and updated its previous document to reflect the expanded scope and demands of current orthodontic education and practice. The members of the task force participated in a thorough revision of the guidelines and created a new document that takes into consideration the didactic, clinical, and the appropriate physical facilities to provide clinical care, study, and research areas. Although it is recognized that there will be variations in teaching and faculty assets, as well as facilities, access to materials, and equipment, the aim of the WFO Educational Guidelines is to provide the minimum program requirements necessary to provide orthodontic specialty residents the educational experience that prepares them to deliver the best level of orthodontic treatment for their patients. It is recommended that these guidelines be used universally by orthodontic specialty program educators and related educational, scientific, and administrative institutions to evaluate and compare their curriculum to a world standard.

External root resorption evaluated by CBCT 3D models superimposition.

INTRODUCTION: The literature reports the association of external root resorption (ERR) with orthodontic movement. In cases of premolars extractions, orthodontic movement of anterior teeth is usually quite expressive, which are precisely the most susceptible teeth to suffer from ERR. OBJECTIVE: The aim of this study was to assess the root morphology of maxillary canines and incisors in patients submitted to four premolar extraction and orthodontic retraction of the anterior teeth, by means of 3D surface models superimposition and mapping. METHODS: The sample consisted of six adult patients, five female and one male, with a mean age of 23.5 ± 6.5 years, who underwent orthodontic treatment. All patients presented bimaxillary dental protrusion, with indication of maxillary and mandibular first premolar extractions, followed by the retraction of anterior teeth and space closure. Cone beam CT scans were performed before the beginning of the treatment (T0) and right after space closure (T1). 3D models were built at both times and superimposed to identify the root changes for the given period. RESULTS: All average differences were close to zero and, even when evaluating the extreme values, the observed changes were always smaller than the accuracy of the CBCT. CONCLUSION: A mild resorption trend was observed, although it was not clinically significant, with values lower than the tomography accuracy.

Dentoskeletal effects of the maxillary splint headgear in the early correction of Class II malocclusion / Effets dento-squelettiques de la force extra-orale sur gouttière maxillaire dans la correction précoce des malocclusions de classe II

Objective: To compare dentoskeletal changes produced by the maxillary splint headgear and cervical headgear appliance during the early phase of Class II treatment, specially the initial overjet and upper incisors position. Subjects and methods: In this retrospective study, 28 Class II patients treated with the maxillary splint headgear (maxillary splint headgear or MSG, mean age 10.1 ± 1.9 years) and 28 Class II patients treated with cervical headgear (cervical headgear group or CHG, mean age 9.5 ± 1.9 years) were evaluated before and after treatment. Statistical comparisons between the two groups for cephalometric measurements at T1 and for T2-T1 changes were performed by means of independent sample t tests. Results: The MSG showed a significantly greater reduction of the overjet in comparison to the CHG (-2.4 mm and -0.7 mm, respectively) and a significantly greater maxillary incisor uprighting (-1.8 mm and 0.4 mm, respectively). In the MSG, overjet correction was due mainly to mandibular advancement (3.5 mm), while the correction of molar relationship (3.9 mm) was 64% skeletal and 36% dentoalveolar. In the CHG, the overjet correction was also more skeletal, due to mandibular growth (1.8 mm), while correction of molar relationship (3.5 mm) was 63% dentoalveolar and 37% skeletal. Conclusions: Both groups showed favorable skeletal mandibular changes, which was more significant in the MSG. Regarding tooth movement, the maxillary splint headgear was more effective in uprighting upper incisors and reducing the overjet than cervical headgear appliance.

Objectif: L'objectif de cet article était de comparer les changements dento-squelettiques produits par la force extra-orale sur gouttière maxillaire et la force extra-orale cervicale pendant la phase précoce du traitement de classe II, en particulier au niveau du surplomb initial et de la position des incisives supérieures. Matériels et méthodes: Dans cette étude rétrospective, les cas de 28 patients en classe II traités avec la force extra-orale sur gouttière maxillaire (maxillary splint headgear ou MSG, âge moyen 10,1 ± 1,9 ans) et de 28 patients en classe II traités avec la force extra-orale à traction cervicale (cervical headgear group ou CHG, âge moyen 9,5 ± 1,9 ans) ont été étudiés avant et après le traitement. Les comparaisons statistiques entre les deux groupes pour les mesures céphalométriques à T1 et pour les changements entre T2 et T1 ont été effectuées au moyen de tests t d'échantillons indépendants. Résultats: Le MSG a montré une réduction significativement plus importante du surplomb par rapport au CHG (-2,4 mm et -0,7 mm, respectivement) et un redressement significativement plus important des incisives maxillaires (-1,8 mm et 0,4 mm, respectivement). Dans le MSG, la correction du surplomb était principalement due à l'avancement mandibulaire (3,5 mm), tandis que la correction de la relation molaire (3,9 mm) était à 64 % squelettique et à 36 % dento-alvéolaire. Dans le CHG, la correction du surplomb était également plus squelettique, en raison de la croissance mandibulaire (1,8 mm), tandis que la correction de la relation molaire (3,5 mm) était à 63 % dento-alvéolaire et à 37 % squelettique. Conclusions: Les deux groupes ont présenté des modifications squelettiques mandibulaires favorables, qui étaient plus significatives dans le groupe MSG. En ce qui concerne le mouvement des dents, la force extra-orale sur gouttière maxillaire était plus efficace pour redresser les incisives supérieures et réduire le surplomb que la force extra-orale cervicale.

Dentoskeletal effects of the maxillary splint headgear in the early correction of Class II malocclusion.

BACKGROUND: To compare dentoskeletal changes produced by the maxillary splint headgear and cervical headgear appliance during the early phase of Class II treatment, specially the initial overjet and upper incisors position. SUBJECTS AND METHODS: In this retrospective study, 28 Class II patients treated with the maxillary splint headgear (MSG, mean age 10.1 ± 1.9 years) and 28 Class II patients treated with cervical headgear (CHG, mean age 9.5 ± 1.9 years) were evaluated before and after treatment. Statistical comparisons between the two groups for cephalometric measurements at T1 and for T2-T1 changes were performed by means of independent sample t tests. RESULTS: The MSG showed a significantly greater reduction of the overjet in comparison to the CHG (- 2.4 mm and - 0.7 mm, respectively) and a significantly greater maxillary incisor uprighting (- 1.8 mm and 0.4 mm, respectively). In the MSG, overjet correction was due mainly to mandibular advancement (3.5 mm), while the correction of molar relationship (3.9 mm) was 64% skeletal and 36% dentoalveolar. In the CHG, the overjet correction was also more skeletal, due to mandibular growth (1.8 mm), while correction of molar relationship (3.5 mm) was 63% dentoalveolar and 37% skeletal. CONCLUSIONS: Both groups showed favorable skeletal mandibular changes, which was more significant in the MSG. Regarding tooth movement, the maxillary splint headgear was more effective in uprighting upper incisors and reducing the overjet than cervical headgear appliance.

Reproducibility of digital indirect bonding technique using three-dimensional (3D) models and 3D-printed transfer trays.

OBJECTIVE: To evaluate the reproducibility of digital tray transfer fit on digital indirect bonding by analyzing the differences in bracket positions. MATERIALS AND METHODS: Digital indirect bonding was performed by positioning brackets on digital models superimposed by tomography using Ortho Analyzer (3Shape) software. Thirty-three orthodontists performed indirect bonding on prototyped models of the same malocclusion using prototyped transfer trays for two types of brackets (MiniSprint Roth and BioQuick self-ligating). The models with brackets were scanned using an intraoral scanner (Trios, 3Shape). Superimpositions were made between the digital models obtained after indirect bonding and those from the original virtual setup. To analyze the differences in bracket positions, three planes were examined for each bracket: vertical, horizontal, and angulation. Three orthodontists repeated indirect bonding after 15 days, and Bland-Altman plots and intraclass correlation coefficients were used to evaluate inter- and intraevaluator reproducibility and reliability, respectively. Repeated-measures analysis of variance (ANOVA) was used to analyze the differences between bracket positions, and multivariate ANOVA was used to evaluate the influence of orthodontists' experience on the results. RESULTS: Differences between bracket positions were not statistically significant, except mesial-distal discrepancies in the BioQuick group (P = .016). However, differences were not clinically significant (horizontal varied from 0.04 to 0.13 mm; angulation, 0.45° to 2.03°). There was no significant influence of orthodontist experience and years of clinical practice on bracket positions (P = .314 and P = .158). The reproducibility among orthodontists was confirmed. CONCLUSIONS: The reproducibility of digital indirect bonding was confirmed in terms of bracket positions using three-dimensional printed transfer trays.

Evaluation of palate area before and after rapid maxillary expansion, using cone-beam computed tomography.

OBJECTIVE: The aim of this study was to estimate the changes in the palate area after rapid maxillary expansion (RME) with the Hyrax expander in growing subjects, using cone beam computed tomography (CBCT). METHODS: Fourteen patients (9 girls and 5 boys; mean age = 11.7 ± 2.4 years) who required RME as part of their orthodontic treatment were included in this study. CBCT records had been taken before RME treatment (T0), at the end of active expansion (T1) and after a 6-month retention period (T2). The CBCT scans were manipulated with Dolphin Imaging® version 11.7 Premium software, in which landmarks were positioned and measured in relation to sagittal, coronal and axial planes, to verify the palate surface area. In addition, linear measurements of the palatal depth and width were assessed. These measurements were compared by using analysis of variance (ANOVA) for repeated measures. A p-value smaller than 0.05 was considered statistically significant. RESULTS: The palatal surface area and width significantly increased from T0 to T1, respectively by 9.27% and 9.71%, and both decreased in a non-significant manner from T1 to T2. The palatal depth had non-significant differences at T0, T1 and T2. CONCLUSIONS: RME promotes a significant gain in the surface area of the palate and an increase in intermolar width. The Hyrax appliance was effective for the treatment of maxillary atresia in growing patients. There was no vertical alteration of the palate. After a 6-month retention period, the maxilla transverse dimension and the surface area of the palate remained stable.

Can lingual spurs alter the oral health-related quality of life during anterior open bite interceptive treatment? A systematic review

ABSTRACT Introduction: The use of lingual spurs has been described as one efficient option, with great stability of results, but with scarce information of toleration for use in the mixed and permanent dentition phases. Objective: The purpose of this study was to assess the impact of lingual spurs on the oral health-related quality of life of children and/or adolescents during anterior open bite treatment. Methods: The review was recorded in the PROSPERO database. Eight electronic databases and partial gray literature were searched, without restrictions until march 2022. A manual search was also performed in the references of the included articles. Studies assessing the impact of lingual spurs on the oral health-related quality of life were included. Risk of bias was assessed using JBI or ROBINS-I tool, according to the study design. The level of evidence was assessed through GRADE. Results: Five studies met the eligibility criteria. Two non-randomized clinical trials had a serious risk of bias. Of the case-series studies, two had a low risk of bias and the other, a moderate risk of bias. The certainty of the evidence was classified as very low for all the evaluated results. In general, the studies reported an initial negative impact with the use of lingual spurs, however this was transitory in nature. A quantitative analysis was not performed due to the great heterogeneity between the studies. Conclusion: Current evidence, although limited, suggests that lingual spurs have an initial transient negative impact during interceptive treatment. Additional well-conducted randomized clinical trials are needed.

RESUMO Introdução: O uso de esporões linguais tem sido descrito como uma opção eficiente, com grande estabilidade de resultados, mas com poucas informações quanto à tolerância de seu uso nas fases de dentição mista e permanente. Objetivo: O objetivo deste estudo foi avaliar o impacto dos esporões linguais na qualidade de vida relacionada à saúde bucal de crianças e/ou adolescentes durante o tratamento da mordida aberta anterior. Métodos: Essa revisão foi registrada no banco de dados PROSPERO. Oito bases de dados eletrônicas e parte da literatura cinzenta foram pesquisadas, sem restrições, até março de 2022. Uma busca manual também foi realizada nas referências dos artigos incluídos. Estudos avaliando o impacto dos esporões linguais na qualidade de vida relacionada à saúde bucal foram incluídos. O risco de viés foi avaliado usando a ferramenta JBI ou ROBINS-I, de acordo com o desenho do estudo. O nível de evidência foi avaliado por meio do GRADE. Resultados: Cinco estudos preencheram os critérios de elegibilidade. Dois ensaios clínicos não randomizados apresentaram sério risco de viés. Dos estudos de série de casos, dois tiveram baixo risco de viés e o outro, risco moderado de viés. A certeza da evidência foi classificada como muito baixa para todos os resultados avaliados. Em geral, os estudos relataram um impacto negativo inicial com o uso dos esporões linguais; porém, de caráter transitório. Não foi realizada análise quantitativa, devido à grande heterogeneidade entre os estudos. Conclusão: As evidências atuais, embora limitadas, sugerem que os esporões linguais têm um impacto negativo transitório inicial durante o tratamento interceptativo. São necessários mais ensaios clínicos randomizados bem conduzidos.

External root resorption evaluated by CBCT 3D models superimposition

ABSTRACT Introduction: The literature reports the association of external root resorption (ERR) with orthodontic movement. In cases of premolars extractions, orthodontic movement of anterior teeth is usually quite expressive, which are precisely the most susceptible teeth to suffer from ERR. Objective: The aim of this study was to assess the root morphology of maxillary canines and incisors in patients submitted to four premolar extraction and orthodontic retraction of the anterior teeth, by means of 3D surface models superimposition and mapping. Methods: The sample consisted of six adult patients, five female and one male, with a mean age of 23.5 ± 6.5 years, who underwent orthodontic treatment. All patients presented bimaxillary dental protrusion, with indication of maxillary and mandibular first premolar extractions, followed by the retraction of anterior teeth and space closure. Cone beam CT scans were performed before the beginning of the treatment (T0) and right after space closure (T1). 3D models were built at both times and superimposed to identify the root changes for the given period. Results: All average differences were close to zero and, even when evaluating the extreme values, the observed changes were always smaller than the accuracy of the CBCT. Conclusion: A mild resorption trend was observed, although it was not clinically significant, with values lower than the tomography accuracy.

RESUMO Introdução: A literatura relata a associação de reabsorção radicular externa (RRE) com a movimentação ortodôntica. Nos casos de extrações de pré-molares, a movimentação ortodôntica costuma ser bastante expressiva nos dentes anteriores, que são justamente os dentes mais suscetíveis à RRE. Objetivo: O objetivo do presente estudo foi avaliar a morfologia radicular de caninos e incisivos superiores em pacientes submetidos à extração de quatro pré-molares e retração ortodôntica dos dentes anteriores, por meio da sobreposição e mapeamento de modelos 3D. Métodos: A amostra foi composta por seis pacientes adultos, cinco do sexo feminino e um do masculino, com média de idade de 23,5 ± 6,5 anos, submetidos a tratamento ortodôntico. Todos os pacientes apresentavam biprotrusão dentária, com indicação de extração dos primeiros pré-molares superior e inferior, seguida de retração dos dentes anteriores e fechamento do espaço. A tomografia computadorizada de feixe cônico (TCFC) foi realizada antes do início do tratamento (T0) e logo após o fechamento de espaços (T1). Modelos 3D foram construídos em ambos os momentos e sobrepostos para identificar as mudanças nas raízes dentárias no período determinado. Resultados: Todas as médias das diferenças foram próximas de zero e, mesmo avaliando os valores extremos, as mudanças observadas foram sempre menores que a sensibilidade da TCFC. Conclusão: Observou-se tendência de leve reabsorção, embora não clinicamente significativa, com valores inferiores à sensibilidade tomográfica.

The ability of orthodontists and oral/maxillofacial surgeons to predict eruption of lower third molar.

BACKGROUND: The aim of this study was to evaluate the ability of oral/maxillofacial surgeons (OMFSs) and orthodontists to predict third molar eruption by examining a simple panoramic radiograph in cases where full spontaneous eruption occurred. METHODS: Panoramic radiographs of 17 patients, 13-16 years of age, were obtained just after orthodontic treatment (T1), when the third molars were intraosseous. The radiographs at T1 were presented to 28 OMFSs and 28 orthodontists-who were asked to give a prognosis for the lower third molars on both sides (n = 34). The full spontaneous eruption of all third molars was clinically observed when patients were older than 18 years (T2). These teeth were clinically asymptomatic at T1 and T2. RESULTS: OMFSs decided by extractions in 49.6 % of cases while orthodontists in 37.8 % (p < 0.001), when the radiographs were examined at T1. Agreement between OMFSs and orthodontists was excellent (Kappa = 0.76, p < 0.0001), as well as intragroup agreement for both OMFSs (Kappa = 0.83) and orthodontists (Kappa = 0.96). CONCLUSIONS: Despite a remarkable agreement for third molar prognosis, orthodontists and OMFSs were unable to predict lower third molar eruption by examining a simple panoramic radiograph. Both indicated extractions of a considerable number of spontaneously erupted asymptomatic teeth.

Evaluation of palate area before and after rapid maxillary expansion, using cone-beam computed tomography

ABSTRACT Objective: The aim of this study was to estimate the changes in the palate area after rapid maxillary expansion (RME) with the Hyrax expander in growing subjects, using cone beam computed tomography (CBCT). Methods: Fourteen patients (9 girls and 5 boys; mean age = 11.7 ± 2.4 years) who required RME as part of their orthodontic treatment were included in this study. CBCT records had been taken before RME treatment (T0), at the end of active expansion (T1) and after a 6-month retention period (T2). The CBCT scans were manipulated with Dolphin Imaging® version 11.7 Premium software, in which landmarks were positioned and measured in relation to sagittal, coronal and axial planes, to verify the palate surface area. In addition, linear measurements of the palatal depth and width were assessed. These measurements were compared by using analysis of variance (ANOVA) for repeated measures. A p-value smaller than 0.05 was considered statistically significant. Results: The palatal surface area and width significantly increased from T0 to T1, respectively by 9.27% and 9.71%, and both decreased in a non-significant manner from T1 to T2. The palatal depth had non-significant differences at T0, T1 and T2. Conclusions: RME promotes a significant gain in the surface area of the palate and an increase in intermolar width. The Hyrax appliance was effective for the treatment of maxillary atresia in growing patients. There was no vertical alteration of the palate. After a 6-month retention period, the maxilla transverse dimension and the surface area of the palate remained stable.

RESUMO Objetivo: o objetivo do presente estudo foi estimar a alteração na área do palato após expansão rápida da maxila (ERM) com o expansor Hyrax em indivíduos em crescimento, utilizando tomografia computadorizada de feixe cônico (TCFC). Métodos: quatorze pacientes (9 meninas e 5 meninos; idade média 11,7± 2,4 anos) que necessitavam de ERM como parte de seu tratamento ortodôntico foram incluídos nesse estudo. Os registros de TCFC foram obtidos antes do tratamento com ERM (T0), ao término da expansão ativa (T1) e após um período de contenção de 6 meses (T2). Os exames de TCFC foram manipulados no software Dolphin Imaging® versão 11.7 Premium, no qual os pontos anatômicos foram posicionados e medidos em relação aos planos sagital, coronal e axial, para verificar-se a área de superfície do palato. Além disso, medidas lineares da profundidade e largura do palato foram avaliadas. Essas medidas foram comparadas por análise de variância (ANOVA) para medidas repetidas. Valores de p< 0,05 foram considerados estatisticamente significativos. Resultados: a área de superfície e a largura do palato aumentaram significativamente de T0 para T1, respectivamente em 9,27% e 9,71%, e ambas diminuíram de forma não significativa de T1 para T2. A profundidade do palato teve diferenças não significativas em T0, T1 e T2. Conclusões: a ERM promove ganho significativo na área de superfície do palato e aumento na largura intermolar. O aparelho Hyrax foi efetivo para o tratamento da atrasia maxilar em pacientes em crescimento. Não houve alteração vertical no palato. Após um período de contenção de 6 meses, a dimensão transversal da maxila e a área de superfície do palato permaneceram estáveis.