Abordagem de incisivos centrais superiores traumatizados: relato de caso / Approach to traumati zed maxillary central incisors: case report

Introdução: O traumatismo dentário é uma ocorrência frequente durante a infância e adolescência. Geralmente, o diagnóstico acontece de forma tardia, devido à falta de conhecimento da população. Cada tipo de trauma necessita de uma conduta única e especializada. Nos casos de comprometimento pulpar, é necessário cuidado quanto à escolha da técnica a ser empregada, bem como a seleção da medicação intracanal que, por sua vez, apresenta grande interferência no sucesso do tratamento. Não obstante o avanço das técnicas de instrumentação, a troca da medicação entre as sessões nesses casos é mandatória. Relato de caso: Um paciente, sexo masculino, em idade escolar (15 anos) apresentou-se ao serviço de saúde bucal com relato de escurecimento e dores na mastigação após trauma dentário durante a infância. Os testes de vitalidade pulpar revelaram necrose pulpar, com resultado negativo no teste térmico e positivo na percussão. O exame radiológico evidenciou uma lesão apical, juntamente com reabsorção externa no elemento 21, confirmado em tomografia. O paciente foi submetido a um tratamento endodôntico. Resultado: Após o tratamento, foi solicitado novo exame tomográfico, em que se evidenciou um processo de cicatrização óssea no periápice e reabsorção por substituição na lesão cervical. Conclusão: A partir deste caso clínico, pôde-se evidenciar a importância do diagnóstico adequado, do manejo e da técnica endodôntica eficaz na resolução de problemas decorrentes de traumas dentários em pacientes jovens.

Introduction: Dental trauma is a frequent occurrence during childhood and adolescence. Generally, diagnosis happens late, due to lack of knowledge among the population. Each type of trauma requires a unique and specialized approach. In cases of pulp involvement, care must be taken when choosing the technique to be used, as well as the selection of intracanal medication, which, in turn, has a major impact on the success of the treatment. Despite advances in instrumentation techniques, changing medication between sessions in these cases is mandatory. Case report: A male patient of school age (15 years old) presented to the oral health service with reports of darkening and pain when chewing following dental trauma during childhood. Pulp vitality tests revealed pulp necrosis, with a negative result in the thermal test and positive in percussion. The radiological examination showed an apical lesion, together with external resorption in element 21, confirmed on tomography. The patient underwent endodontic treatment. Result: After treatment, a new tomographic examination was requested, which showed a process of bone healing in the periapex and resorption by replacement in the cervical lesion. Conclusion: From this clinical case, it was possible to highlight the importance of adequate diagnosis, management, and effective endodontic technique in solving problems arising from dental trauma in young patients.

Digital analysis of the correlation between gingival thickness and alveolar bone thickness in the maxillary anterior teeth region / 中华口腔医学杂志

Objective: To measure the labial gingival thickness and bone lamella thickness in the maxillary anterior area using digital method, and to analyze the correlation between the two, so as to provide a reference for esthetic restoration and implantation treatment of the upper anterior area. Methods: Fifty-seven patients [23 males, 34 females, (25.8±4.5) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to October 2020. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. The image data was fitted and registered by the 3Shape software. The gingival thickness at 2 mm below the gingival margin, bone thickness and gingival thickness at 2 and, 4 mm below the crest of the labial alveolar crest in maxillary central incisors, lateral incisors and canines, were measured. Results: The gingival thickness at 2 mm below the gingival margin of maxillary central incisors, lateral incisors and canines was (1.42±0.21), (1.19±0.17) and (1.23±0.20) mm respectively (F=12.47, P<0.001). The gingival thickness at 2 mm below gingival margin and 4 mm below crest of residual ridge in the male patients were (1.31±0.21) and (0.67±0.22) mm, and those in the female patients were (1.26±0.22) and (0.58±0.19) mm respectively, and there were statistically significant differences in the gingival thickness between the "2 mm below gingival margin" group and the "4 mm below crest of residual ridge" group (t=2.01 and 3.97, P<0.05). There was a positive correlation between gingival thickness and alveolar bone thickness at 2 mm and 4 mm below the crest of residual ridge in maxillary anterior region, and the correlation coefficients (r) were 0.387 and 0.344 respectively (P<0.05). Conclusions: Gingival thickness of maxillary anterior area is related to the tooth position and gender. The gingival thickness of men is greater than that of women.The gingival thickness at 2 and 4 mm below the crest of the alveolar crest is positively correlated with the thickness of the alveolar bone.

Three-dimensional morphology analysis of the supraosseous gingival profile of periodontally healthy maxillary anterior teeth / 北京大学学报(医学版)

OBJECTIVE@#To measure the three-dimensional morphology of the labial supraosseous gingiva (SOG) and the thickness of related labial bone in maxillary anterior teeth of periodontally healthy Han nationality youth using soft tissue indirect imaging cone-beam computed tomography (CBCT).@*METHODS@#Twenty-five periodontally healthy subjects (11 males and 14 females) with 150 maxillary anterior teeth were involved in this study. A special impression with radiopaque material including the maxillary teeth was made, then a CBCT scan with the elastomeric matrix in position was taken for each subject. The imaging data were generated and transferred to a volumetric imaging software in which three-dimensional reconstruction was conducted and the image analyses were carried out. Measurements were made at the site of labial center of the maxillary anterior teeth. The height of the SOG, the distance between cemento-enamel junction (CEJ) and bone crest, the gingival thickness at the CEJ, and the thickness of bone 2 mm below the labial bone crest were measured and the correlation analysis between the parameters was made. All the data analyses were performed using SPSS 22.0. The data were analyzed with ANVOA and Pearson correlation tests with the significance level at α=0.05.@*RESULTS@#The mean SOG values were (3.49±0.70) mm, (3.48±0.81) mm, and (3.54±0.67) mm for central incisors, lateral incisors and canines, respectively. There were no statistically significant differences among the different sites (P > 0.05). The mean gingival thickness values were (1.45±0.23) mm, (1.13±0.24) mm, (1.14±0.22) mm for central incisors, lateral incisors and canines, respectively. The gingival thickness of the central incisors was the largest among the maxillary anterior teeth with statistically significant difference (P < 0.05). No correlation was found between the SOG and gingival thickness among the maxillary anterior teeth (P > 0.05).@*CONCLUSION@#The gingival thickness of central incisors was the largest and the supraosseous gingival height had no correlation with gingival thickness among the periodontally healthy maxillary anterior teeth.

The correlation between external apical root resorption and electric pulp test responses: a prospective clinical trial

ABSTRACT Objective: The current study investigated the correlation between pulpal sensitivity to the electric pulp tester (EPT) and external apical root resorption (EARR) in four types of maxillary anterior teeth of fixed orthodontic treatment patients. Methods: In this prospective cohort study, 232 anterior teeth of 58 patients (mean age 18.96 ± 6.13 years) treated with fixed orthodontic treatment were examined. The EPT readings were recorded at twelve time points immediately before archwire insertion. Root resorption of four maxillary incisors were measured by means of parallel periapical radiographs at three time intervals (six months interval from the start) through design-to-purpose software to optimize data collection. A multiple linear regression model and Pearson correlation coefficient were used to assess the association of EPT values and observed EARR (p< 0.05). Results: The highest level of EPT measurement was recorded at initial visit, and then there was a decreasing trend in EPT level during treatment for the next six and twelve months. There was another increasing trend after six months till the finishing time of the treatment. There was a significant correlation between changes in root length and time of recording the root length (p< 0.001). There was significant positive correlation between changes in EPT level and amount of observed root resorption (p< 0.001). Conclusion: The relative decrease in electric pulp test level could be a diagnostic sign of root resorption during orthodontic treatment. Further studies with longer follow up are needed to confirm the current results.

RESUMO Objetivo: O presente estudo investigou a correlação entre a sensibilidade pulpar ao teste pulpar elétrico (TPE) e a reabsorção radicular apical externa (RRAE) nos quatro dentes anteriores superiores de pacientes em tratamento ortodôntico com aparelho fixo. Métodos: Nesse estudo de coorte prospectivo, foram avaliados 232 dentes anteriores de 58 pacientes (idade média 18,96 ± 6,13 anos) tratados com aparelho ortodôntico fixo. As leituras do TPE foram registradas em doze tempos de avaliação, imediatamente antes da inserção dos arcos. As reabsorções radiculares dos quatro incisivos superiores foram aferidas por meio da média das radiografias periapicais, em três intervalos de tempo (em intervalos de seis meses desde o início) por um software desenvolvido para essa finalidade, com o intuito de otimizar a coleta de dados. Para aferir a associação entre os valores de TPE e as RRAE observadas (p< 0,05), foram utilizados o modelo de regressão linear múltiplo e o coeficiente de correlação de Pearson. Resultados: O nível mais alto das medidas do TPE foi registrado na primeira visita e, daí em diante, houve uma tendência de diminuição no nível do TPE durante o tratamento, nos seis a doze meses seguintes. Houve, também, outra tendência de aumento após os seis meses até o término do tratamento, além de uma correlação significativa entre as mudanças no comprimento radicular e o tempo de registro do comprimento radicular (p< 0,001), bem como uma correlação positiva significativa entre as mudanças no nível do TPE e a quantidade de reabsorção radicular observada (p< 0,001). Conclusão: Uma diminuição relativa no nível de sensibilidade ao teste pulpar elétrico pode ser um sinal diagnóstico de reabsorção radicular durante o tratamento ortodôntico. Estudos futuros com acompanhamentos mais longos são necessários para confirmar os presentes resultados.

An eye-tracking and visual analogue scale attractiveness evaluation of black space between the maxillary central incisors

ABSTRACT Objective: To study the influence of black space between the maxillary central incisors on the aesthetic visual perception of the face, via eye-tracking and visual analogue scale (VAS). Methods: Black space between the central incisors was created, for both sexes, as follows: control, 1-mm black space, 2-mm black space and 3-mm black space. Ninety raters participated in this study, divided into three groups: 30 laypeople, 30 nonorthodontists, and 30 orthodontists. After the visual calibration of each observer, eight photographs were presented in the Ogama® software concomitant with the use of the hardware The Eye Tribe®. Ogama generated information depending on the eye-tracking of each rater, regarding the time until the first fixation, time of fixation, heatmap, scanpath, and total time of fixation, to evaluate the areas deemed to be of interest according to the raters. Later on, the VAS was used, where each rater evaluated the images in an album on a scale of zero to 10 points. Results: The eyes and mouth were the areas more often noticed by the raters according to the heatmaps, while no significant difference was observed in time until the first fixation between the three groups of raters (p> 0.05). However, regarding the time of fixation on the mouth, a significant difference was observed (p< 0.05) when comparing the three groups. Conclusion: Black space has a negative effect on the aesthetic perception of the face. The amount of attention on the mouth is correspondent to the size of the black space.

RESUMO Objetivo: Avaliar a percepção visual e estética do espaço negro entre os incisivos centrais superiores, via rastreamento do olhar e escala visual analógica (EVA). Métodos: Manipulou-se o espaço negro entre os incisivos centrais superiores, para ambos os sexos, da seguinte forma: imagem controle, espaço negro de 1 mm, espaço negro de 2 mm e espaço negro de 3 mm. Participaram desse estudo noventa avaliadores, divididos em três grupos: 30 leigos, 30 cirurgiões-dentistas e 30 ortodontistas. Após a calibração visual de cada observador, foram projetadas oito fotografias no software OGAMA® em conjunto com o hardware The Eye Tribe®. O OGAMA gerou informações do rastreamento do olhar de cada avaliador com relação ao tempo até a primeira fixação, mapa de calor, trajetória do olhar e tempo total de fixação para avaliar as áreas consideradas de interesse, de acordo com os avaliadores. Posteriormente, utilizou-se a EVA para avaliar as imagens a partir de um álbum, em uma escala de 0 a 10 pontos. Resultados: Os olhos e a boca foram as áreas com maior fixação pelos avaliadores, de acordo com os mapas de calor. Os resultados estatísticos não apresentaram diferença estatisticamente significativa entre os três grupos de avaliadores (p> 0,05), quanto ao tempo até a primeira fixação. Porém, em relação ao tempo de fixação na boca, observou-se diferença estatisticamente significativa (p< 0,05) na comparação dos três grupos. Conclusão: O espaço negro apresentou um efeito negativo na percepção estética da face. O aumento de fixação na boca correspondeu ao aumento do tamanho do espaço negro.

Conservative treatment in adult patient with reimplanted anterior teeth after traumatic avulsion with extensive bone loss: an 8-year follow-up

ABSTRACT Introduction: Orthodontic treatment in patients with traumatized teeth is a condition that needs good planning in order to achieve satisfactory results. Objective: To discuss approaches to orthodontic treatment of malocclusions associated with trauma followed by avulsion of anterior teeth, reimplanted after a short period of time. Case report: The treatment started with the distalization of upper posterior teeth, with the aid of mini-implants and sliding jigs, followed by the inclusion of anterior teeth in the arch, followed by intrusion of these teeth. Results: With the treatment, improved mobility of the anterior teeth was achieved, with better insertion into bone tissue. The most important factor for satisfactory treatment and a good prognosis for avulsion is the time the tooth remains outside the socket. Orthodontic treatment in patients with traumatized teeth is not contraindicated; however, clinical and radiographic aspects must be considered. Conclusion: Among the feasible orthodontic treatment options, the conservative approach can be a very favorable treatment alternative.

RESUMO Introdução: O tratamento ortodôntico em pacientes com dentes traumatizados é uma condição que necessita de um bom planejamento, a fim de se conseguir resultados satisfatórios. Objetivo: Discutir as abordagens de tratamento ortodôntico de más oclusões associadas ao trauma seguido de avulsão de dentes anteriores, reimplantados após curto espaço de tempo. Relato do Caso: O tratamento realizado iniciou-se com a distalização dos dentes posteriores superiores, com auxílio de mini-implantes e sliding jigs, seguida da inclusão dos dentes anteriores na arcada e intrusão desses dentes. Resultados: Com a realização do tratamento, conseguiu-se melhoria na mobilidade dos dentes anteriores, com inserção mais favorável no tecido ósseo. O fator mais importante para o tratamento satisfatório e um bom prognóstico da avulsão é o tempo em que o dente permanece fora do alvéolo. O tratamento ortodôntico em pacientes com dentes traumatizados não é contraindicado; porém, aspectos clínicos e radiográficos devem ser considerados. Conclusão: Entre as opções de tratamento ortodôntico factíveis, a abordagem conservadora pode ser uma opção de tratamento bastante favorável.

Invasive cervical resorption of central incisor during orthodontic treatment

ABSTRACT Introduction: Invasive cervical resorption (ICR) is a relatively rare type of ERR (External Root Resorption), in which a localized resorption begins in the cervical area of the tooth, below the epithelial junction and above the ridge crest. Objective: Describe the clinical case of an 11-year-old boy with no dental trauma history, presenting moderate crowding and ectopic eruption of the maxillary right central incisor. He had been undergoing orthodontic treatment elsewhere, and his family was dissatisfied with the results. Description: A new treatment was indicated, which included rapid maxillary expansion followed by extraction of four premolars. During routine panoramic evaluation, a radiolucid image was detected and a periapical radiograph was requested. At this point, an ICR of the maxillary right central incisor was found. The treatment was cautiously finalized and despite the use of light forces, central incisor was severally compromised by ICR and was therefore extracted. Conclusion: This clinical example discusses the importance of routine radiographs for the early diagnoses of ICR.

RESUMO Introdução: A reabsorção cervical invasiva (RCI) é um tipo relativamente raro de reabsorção radicular externa (RRE), no qual uma reabsorção localizada começa na região cervical do dente, abaixo da junção epitelial e acima da crista marginal. Objetivo: Descrever o caso clínico de um menino com 11 anos de idade, sem histórico de trauma dentário, apresentando apinhamento moderado e erupção ectópica do incisivo central superior. Ele realizava tratamento ortodôntico em outro local, mas sua família estava insatisfeita com os resultados. Descrição: Foi iniciado um novo tratamento, que incluiu a expansão rápida da maxila, seguida pela extração de quatro pré-molares. Durante a avaliação de rotina da radiografia panorâmica, uma imagem radiolúcida foi detectada, e uma radiografia periapical da região foi solicitada, sendo encontrada uma RCI no incisivo central superior direito. O tratamento foi finalizado com cautela e, apesar do uso de forças leves, o incisivo central estava seriamente comprometido pela RCI e, portanto, precisou ser extraído. Conclusão: Esse exemplo clínico discute a importância das radiografias de rotina para o diagnóstico precoce da RCI.

Association between hypodontia of permanent maxillary lateral incisors and other dental anomalies

ABSTRACT Introduction: Tooth agenesis is often associated with other tooth anomalies, such as microdontia, delayed eruption and ectopic eruption. Moreover, they may be found all in the same individual, as certain genetic mutations may have a variable phenotypic expression. Treatment of cases of hypodontia of anterior teeth should not involve only opening or closing space for prosthetic rehabilitation. Individuals with hypodontia of permanent maxillary lateral incisors may have teeth with a mesiodistal width smaller than that of patients with a normal dentition, and which may need reshaping to achieve an esthetic and functional occlusion. Objective: This clinical case report discusses the association of hypodontia of permanent maxillary lateral incisors with other tooth anomalies and their treatment alternatives.

RESUMO Introdução: As agenesias dentárias são frequentemente associadas a outras anomalias dentárias, tais como microdontia, atraso na erupção e ectopismo. Além disso, podem vir todas juntas em um mesmo indivíduo, pois certas mutações genéticas podem se expressar fenotipicamente de diferentes formas. A abordagem terapêutica nos casos de hipodontia de dentes anteriores não deve se pautar somente entre fechar ou abrir espaço para substituição protética. Portadores de hipodontia de incisivos laterais superiores permanentes podem apresentar os outros dentes com largura mesiodistal menor que os de pacientes com dentição normal, e podem necessitar de reanatomizações para que se obtenha uma oclusão dentária estética e funcional. Objetivo: Dessa forma, o objetivo do presente artigo é relatar um caso clínico e discutir a associação da hipodontia de incisivos laterais superiores permanentes com outras anomalias dentárias, e suas alternativas de tratamento.

Evaluation of diagnostic agreement among cephalometric measurements for determining incisor position and inclination / Evaluación de la concordancia diagnóstica entre mediciones cefalométricas para la determinación de la posición e inclinación de los incisivos

SUMMARY: The incisors are a key factor in dental occlusion and dentofacial aesthetics; therefore, the sagittal position and inclination of the incisors is a key parameter in diagnosis and orthodontic treatment planning. In some cases, the orthodontist will use more than one cephalometric analysis, and thus different results can be obtained. The aim of this study was to establish the diagnostic agreement among the different cephalometric measurements used to determine the anteroposterior position and the inclination of the incisors. Lateral cephalometric radiograms of patients between 18 and 59 years old were measured (n=260). Digital cephalometric measurements were made with Dolphin Imaging software, by a single calibrated operator. Here, a specific cephalometric analysis was designed in the software analysis editor. The results for each variable and each measurement were registered and compared. Fleiss's Kappa statistical tests, Cohen's Kappa, and Kendall's coefficient were used to determine the strength of agreement using the Minitab software. The results showed diagnostic strength agreement between slight and moderate among measurements of the same variable. This indicates that same diagnosis might not be obtained when using different approaches to measure the anteroposterior position and inclination of the incisors. It was concluded that there is a difference in the diagnosis between one measurement and another because the results showed slight or moderate strength of agreement. However, in some cases, better agreement was found when the measurements were compared as a function of the diagnostic response.

RESUMEN: Los incisivos son un factor clave en la oclusión dental y la estética dentofacial; por lo tanto, la posición sagital y la inclinación de los incisivos es un parámetro clave en el diagnóstico y la planificación del tratamiento de ortodoncia. En algunos casos, el ortodoncista utilizará más de un análisis cefalométrico y, por lo tanto, se pueden obtener resultados diferentes. El objetivo de este estudio fue establecer el acuerdo de diagnóstico entre las diferentes mediciones cefalométricas utilizadas para determinar la posición anteroposterior y la inclinación de los incisivos. Se midieron radiografías cefalométricas laterales de pacientes entre 18 y 59 años (n = 260). Las mediciones cefalométricas digitales se realizaron con el software Dolphin Imaging, por un solo operador calibrado. Aquí, se diseñó un análisis cefalométrico específico en el editor de análisis de software. Los resultados para cada variable y cada medición se registraron y compararon. Las pruebas estadísticas Kappa de Fleiss, Kappa de Cohen y el coeficiente de Kendall se usaron para determinar la fuerza del acuerdo utilizando el software Minitab. Los resultados mostraron un acuerdo de fuerza diagnóstica entre leve y moderado entre las mediciones de la misma variable. Esto indica que no se puede obtener el mismo diagnóstico cuando se utilizan diferentes enfoques para medir la posición anteroposterior y la inclinación de los incisivos. Se concluyó que existe una diferencia en el diagnóstico entre una medición y otra porque los resultados mostraron una fuerza de acuerdo leve o moderada. Sin embargo, en algunos casos, se encontró un mejor acuerdo cuando se compararon las mediciones en función de la respuesta de diagnóstico.

Incisor root length in individuals with and without anterior open bite: a comparative CBCT study

ABSTRACT Objective: This study aimed to compare the root length of maxillary and mandibular incisors between individuals with open bite versus matched individuals with adequate overbite. Methods: This comparative, matched and retrospective study included 48 cone beam computed tomographies (CBCTs) obtained at a university radiological center. Scans belonged to 24 individuals with open bite (overbite ≤ 0 mm) and 24 individuals with adequate overbite (controls). Both groups were matched by age, sex, malocclusion classification and skeletal characteristics (ANB and FMA angles). Root length of each maxillary and mandibular incisor was measured in millimeters (mm) in a sagittal section from a perpendicular line to the enamel cement junction until the root apex (384 length measurements were made). The means of root length in both groups were compared using t-tests. In addition, correlations between variables were evaluated with the Pearson correlation coefficient (α = 0.05). Results: In both groups, the root length of the upper central incisors was approximately 12 mm and the root length of the maxillary lateral incisors was approximately 13 mm (p˃ 0.05). Likewise, the root length of lower central incisors in both groups measured approximately 12 mm (p˃ 0.05). However, the mandibular lateral incisor roots of open bite patients were significantly longer than in the normal overbite patients (approximately 1 mm, p= 0.012 right side, p= 0.001 left side). Conclusions: Root length of maxillary incisors and central mandibular incisor is similar in individuals with or without open bite, but the mandibular lateral incisor roots in open bite patients were significantly longer than in the normal overbite patients.

RESUMO Objetivo: O presente estudo teve como objetivo comparar o comprimento radicular de incisivos superiores e inferiores em indivíduos com mordida aberta versus indivíduos com sobremordida normal. Método: Esse estudo comparativo e retrospectivo incluiu 48 tomografias computadorizadas de feixe cônico (TCFC) obtidas em um centro radiológico universitário. As tomografias foram realizadas em 24 indivíduos com mordida aberta (sobremordida ≤ 0 mm) e 24 indivíduos com sobremordida normal (controle). Ambos os grupos foram compatibilizados de acordo com a idade, sexo, má oclusão e padrão esquelético (ângulos ANB e FMA). O comprimento radicular de todos os incisivos superiores e inferiores foi medido em milímetros (mm) em um corte sagital, de uma linha perpendicular à junção cemento-esmalte até o ápice radicular (384 medidas de comprimento foram realizadas). A média de comprimento radicular em ambos os grupos foi comparada utilizando-se o teste t. Adicionalmente, correlações entre as variáveis foram avaliadas usando o coeficiente de correlação de Pearson (α = 0,05). Resultados: Em ambos os grupos, o comprimento radicular dos incisivos centrais superiores foi de, aproximadamente, 12 mm, e o comprimento radicular dos incisivos laterais superiores foi de, aproximadamente, 13 mm (p˃ 0,05). Da mesma forma, o comprimento radicular dos incisivos centrais inferiores, em ambos os grupos, obteve a medida de aproximadamente 12 mm (p>0,05). No entanto, o comprimento radicular dos incisivos laterais inferiores em indivíduos com mordida aberta foi significativamente maior em comparação aos pacientes com sobremordida normal (aproximadamente 1 mm, p=0,012 do lado direito, p=0,001 do lado esquerdo). Conclusões: O comprimento radicular de incisivos superiores e incisivos centrais inferiores foi similar em indivíduos com ou sem mordida aberta, mas o comprimento radicular de incisivos laterais inferiores em indivíduos com mordida aberta foi significativamente maior em comparação a pacientes com sobremordida normal.

Vestibular Alveolar bone height measurement: Accuracy and Correlation between direct and indirect techniques / Medición de la altura del hueso alveolar vestibular: precisión y correlación entre técnicas directa e indirecta

ABSTRACT Cone Beam Computed Tomography (CBCT) has modified the perspective of dentistry images, providing manipulable threedimensional images with a 1:1 patient:image ratio. Treatments and diagnosis are modified or corroborated by CBCT; however, its accuracy in thin structures such as cortical bone has been subjected to critical review. The aim of this study is to correlate the measurement of vestibular alveolar bone height using direct measurements and measurements performed with conebeam tomographic images with standard (SD) voxel resolution. Thirty incisor and premolar teeth of patients undergoing open curettage were measured with a highprecision caliper and with Cone Beam Computed Tomography (CBCT) at an SD resolution of 0.16 mm voxels in a 3D Orthophos XG Sirona scanner. Intraobserver evaluation was performed using the intraclass correlation coefficient (ICC). Direct measurements and CBCT measurements were correlated using Pearson correlation (PCC). The mean difference between indirect and direct measurements was 3.15 mm. Paired t test and Pearson Correlation coefficient determined that all measurements differed statistically from each other with p<0.05. With the CT scanner and protocol used in this study, CBCT images do not enable accurate evaluation of vestibular alveolar bone height.

RESUMEN La tomografía de haz cónico (CBCT) ha modificado la perspectiva de la imagenología en odontología que brinda una imagen tridimensional manipulable con una relación 1:1, paciente: imagen. Los tratamientos y diagnósticos se ven modificados o corroborados por el CBCT; sin embargo, la exactitud que presenta en estructuras delgadas como las corticales óseas ha sido sometida a críticas. El objetivo fue correlacionar la medición de la altura del hueso alveolar vestibular mediante mediciones directas y las realizadas con imágenes tomográficas de haz cónico con resolución de vóxel estándar (SD). Treinta dientes incisivos y premolares de pacientes sometidos a un curetaje abierto se midieron con un calibrador de alta precisión y una tomografía computarizada de haz cónico (CBCT) a una resolución SD de 0,16 mm de vóxeles en un escáner 3D Orthophos XG Sirona. La evaluación intraobservador se realizó utilizando el coeficiente de correlación intraclase (ICC), y las mediciones directas y las mediciones CBCT se correlacionaron utilizando la correlación de Pearson (PCC). La diferencia media entre las mediciones indirectas y directas fue de 3,15 mm. La prueba t pareada y el Coeficiente de Correlación de Pearson determinaron que todas las mediciones fueron estadísticamente diferentes entre sí con una p <0.05. Con el escáner de TC y el protocolo utilizado en este estudio, las imágenes CBCT no permiten una evaluación precisa de la altura del hueso alveolar vestibular.

Internal Lower Incisor Morphology revealed by Computerized Microtomography / Morfologia interna de incisivos inferiores reveladas por microtomografía computadorizada

ABSTRACT This study evaluated the internal morphology of lower incisors using computerized microtomography (microCT) images. Eightynine lower incisors were scanned by microCT and reconstructed with NRecon software. 2D parameters (perimeter, root length, circularity and canal diameter) and 3D parameters (volume, surface area and structure model index) were evaluated with CTAn and CTVol software. The results are presented descriptively. It was found that 89.9% of the canals had a single main root canal (type I), followed by type II (6.7%) and III (3.4%), while 5.6% of the specimens presented lateral canals and 1.1% had an apical delta. Mean volume and surface area were 31.80mm³ and 90.58mm², respectively. The most prevalent shape of the root canal at CEJ level was circular (41.6%) and 1mm from the apex, 73% of the samples were classified as oval. Lower incisors with internal anatomical variations may offer a high degree of technical complexity and may result in treatment failure.

RESUMO Este estudo avaliou a morfologia interna dos dentes incisivos inferiores utilizando imagens de microtomografia computado rizada (microTC). 89 incisivos inferiores foram escaneados por microCT e reconstruídos com o programa NRecon. Parâmetros 2D perímetro, comprimento da raiz, circularidade e diâmetro do canal e parâmetros 3D volume, área superficial e índice de modelo de estrutura foram avaliados com os softwares CTAn e CTVol. Os resultados foram apresentados de forma descritiva. 89,9% dos canais apresentaram um único canal radicular principal (tipo I), seguido pelo tipo II (6,7%) e III (3,4%). 5,6% dos espécimes apresentavam canais laterais e 1,1% delta apical. O volume médio e a área de superfície foram 31,80mm³ e 90,58mm², respectivamente. A forma mais prevalente do canal radicular no nível da CEJ foi circular (41,6%) e a 1 mm do ápice, 73% das amostras foram classificadas como ovais. Incisivos inferiores com variações anatômicas internas podem oferecer um alto grau de complexidade técnica e resultar em falha do tratamento.

Cone-beam computed tomography for evaluating root length of maxillary and mandibular anterior teeth in open bite patients / 中南大学学报(医学版)

OBJECTIVES@#To compare the root length of maxillary and mandibular anterior teeth between open bite patients and normal overbite patients via cone-beam computed tomography (CBCT) as well as the root length of anterior teeth in different degree of open bite patients, and to analyze the correlation between the degree of open bite and root length.@*METHODS@#A total of 106 untreated patients were enrolled retrospectively (53 anterior open bite patients and 53 normal overbite patients).Three-dimensional position of the CBCT image for the patient's teeth was performed using Dolphin software. The median sagittal plane of the tooth was used as the measurement plane, and the line connecting the apical point and the midpoint between the labial and lingual cementoenamel junctions was defined as the root length. Independent @*RESULTS@#Significant differences were found in the root length of maxillary and mandibular anterior teeth between the open bite group and the normal overbite group (@*CONCLUSIONS@#The root length of maxillary and mandibular anterior teeth in the open bite patients is shorter than that in the normal overbite patients, and the severer the degree of open bite, the shorter the root length of the mandibular central incisor tends to be. There is a certain relationship between maxillary anterior teeth and the root length of anterior teeth.

Manejo ortodóncico quirúrgico del incisivo superior ectópico / Surgical- orthodontic management of the ectopic upper incisor

La ubicación en la arcada de un incisivo superior ectópico y con diagnóstico de dilaceración, sin duda, es un gran desafío. Ya sea por su alto compromiso estético, así como también, por las maniobras biomecánicas a aplicar. La alteración de forma y ubicación ectópica del incisivo central superior, puede estar dada por un desarrollo anormal de dicha pieza sin causa aparente en el mayor porcentaje de los casos; aunque por causas obstructivas, como la presencia de diferentes patologías: quistes, odontomas, dientes supernumerarios; así como también, en un porcentaje menor, por traumatismos en los dientes temporarios

Age estimation by pulp/tooth area ratio in anterior teeth using cone-beam computed tomography: comparison of four teeth

Abstract Objectives Age estimation is one of the most important factors in forensic medicine. Measuring secondary dentin deposition using cone-beam computed tomography images is an easy and noninvasive method. The aim of this study was to evaluate cone-beam computed tomography images as a reliable method to estimate chronological age by pulp/teeth ratio in anterior teeth in Iranian population. Methodology A total of 649 CBCT images from 377 Iranian patients aged between 20 and 69 years were evaluated. Pulp/teeth ratio (PTR) in maxillary and mandibular canine and central incisor teeth was measured in the axial and sagittal sections using OnDemand 3D Dental software. The Pearson correlation coefficient was determined to evaluate the correlation between the variables. Linear regression analysis, as well as age estimation formula, was used for each tooth separately. Results The regression analyses indicated that maxillary central incisors were more reliable for age estimation (R2=0.586 and standard error of estimate=7.045) compared with the other anterior teeth studied. Maxillary canine teeth had the lowest predictive power (R2=0.392 and standard error of estimate=8.387). Also, comparison of the axial and sagittal sections showed that the axial sections had a higher predictive power. (R2=0.48 for axial plans and R2=0.328 for sagittal plans) Conclusion The use of cone-beam computed tomography in age estimation by pulp/teeth ratio of anterior teeth is useful and a reliable method for age estimation in Iranian population.

Dentoalveolar evaluation of lower incisors by cbct after treatment with herbst appliance

Abstract This study aimed to evaluate the effects of the Herbst appliance on the proclination and protrusion of the lower incisors, and to verify if the device causes alveolar bone loss in the anterior region of the mandible. This is a retrospective study. The sample consisted of 35 individuals. The treatment group consisted of 22 individuals (8 girls and 14 boys; initial mean age of 8.2 years) who used the Cantilever Herbst appliance for a period of 12 months. The control group consisted of 13 individuals (3 girls and 10 boys; initial mean age of 8.9 years) who received no treatment and were followed up for a period of approximately 18 months. Cone-beam computed tomography scans were performed at the beginning and at the end of the observational period. The medullary bone thickness (MT), buccal cortical bone thickness (BCT), lingual cortical bone thickness (LCT), and lower incisors proclination and protrusion were evaluated. Data were submitted to statistical analysis (ANCOVA and Student's t-test) with a significance level of 5%. There was no significant difference in MT, BCT, LCT and incisor proclination between groups. Incisor proclination increased in the treated group with no statistical significance. The treatment group showed a significant increase in the protrusion of the incisors (p = 0.02). The Herbst appliance promoted a small proclination and protrusion of the lower incisors, without relevant clinical implications. The Herbst appliance did not cause bone loss in the anterior region of the mandible during Class II treatment.

Resumo O objetivo deste estudo foi avaliar os efeitos do aparelho de Herbst na proclinação e protrusão dos incisivos inferiores, bem como verificar se o aparelho causa perda óssea alveolar na região anterior da mandíbula. Trata-se de um estudo retrospectivo. Foi utilizada uma amostra de 35 indivíduos. O grupo tratado foi formado por 22 indivíduos (8 meninas e 14 meninos; idade média inicial de 8,2 anos) que utilizaram o aparelho de Herbst com Cantilever por um período de 12 meses. O grupo controle foi composto por 13 indivíduos (3 meninas e 10 meninos; idade média inicial de 8,9 anos) que não receberam tratamento e foram acompanhados por um período de aproximadamente 18 meses. Exames de tomografia computadorizada de feixe cônico foram realizados no início e no final do período observacional. Foram avaliadas a espessura óssea medular (EM), espessura óssea cortical vestibular (ECV), espessura óssea cortical lingual (ECL), proclinação e protrusão dos incisivos inferiores. Os dados foram submetidos a análise estatística (ANCOVA e teste t de Student) com nível de significância de 5%. Não houve alteração estatisticamente significativa na EM, ECV, ECL e proclinação dos incisivos entre os grupos. Houve um aumento na proclinação dos incisivos no grupo tratado, sem significância estatística. O grupo tratado apresentou aumento significativo na protrusão dos incisivos (p=0,02). O aparelho de Herbst promoveu uma pequena proclinação e protrusão dos incisivos inferiores, sem implicações clínicas relevantes. O aparelho de Herbst não causou perda óssea na região anterior da mandíbula durante o tratamento da Classe II.

Side effects of intraoral devices for OSAS treatment / Side effects of intraoral devices for OSAS treatment

Abstract Introduction: Intraoral devices have increasingly assumed a key role in the treatment of obstructive sleep apnea syndrome, but there are limitations to their indication and side effects that result from their continuous use, as well as the use of the continuous positive airway pressure device. Objectives: To evaluate the changes in dental positioning caused by the continuous use of mandibular advancement devices. Methods: A prospective longitudinal study with a sample of 15 patients, with evaluation of complete documentation after a mean time of 6.47 months, assessed changes in dental positioning due to the use of the Twin Block oral device for the treatment of patients with apnea. The following variables were evaluated: overjet, overbite, upper and lower intermolar distances, upper and lower intercanine distances, Little's irregularity index and the incisor mandibular plane angle. An intraclass correlation test was performed and a correlation index > 0.08 was accepted. After verifying the normal sample distribution (Shapiro-Wilks), a parametric test was used (t test), with a significance level set at 5%. Results: There was a decrease in the values of overjet, overbite and Little's irregularity index, whereas there was an increase in the lower intercanine distance and IMPA values. All these variables are influenced, at different levels, by the forward inclination of the lower incisors, an action that can be expected due to the force applied by the device on the dentition. The other variables did not show statistically significant differences. Conclusion: After a mean time of 6.47 months of use of the mandibular advancement device, there were statistically significant changes in the dental positioning, but they were not clinically relevant. However, it is relevant that this device is commonly in use over long periods of time, making the monitoring of these patients of the utmost importance for the duration of their therapy.

Resumo: Introdução: Os aparelhos intraorais têm assumido cada vez mais um papel importante no tratamento da síndrome da apneia obstrutiva do sono, mas existem limitações a sua indicação e efeitos colaterais com o seu uso contínuo, assim como com o uso do aparelho de pressão aérea positiva contínua. Objetivos: Avaliar as alterações no posicionamento dentário produzido pelo uso contínuo do aparelho de projeção mandibular. Método: Através de estudo longitudinal prospectivo com amostra de 15 pacientes, com avaliação de documentações completas após um tempo médio de 6,47 meses do uso do aparelho oral de Twin Block para tratamento de pacientes com apneia, foram avaliadas as alterações do posicionamento dos dentes decorrentes do seu uso. As seguintes variáveis foram avaliadas: overjet, overbite, distâncias intermolares superior e inferior, distâncias intercaninos superior e inferior, índice de irregularidade de Little e ângulo do plano incisivo mandibular. Foi feito teste de correlação intraclasse e foram aceitos índices de correlação acima de 0,08. Após atestada a distribuição normal da amostra (Shapiro-Wilks), foi usado um teste paramétrico (teste t), com nível de significância de 5%. Resultados: Houve diminuição nos valores de overjet, overbite e irregularidade de Little e aumento nos valores da distância intercanino inferior e do ângulo do plano incisivo mandibular. Todas essas variáveis sofrem influência, com diferentes expressividades, da inclinação para frente dos incisivos inferiores, uma ação que pode ser esperada devido à força aplicada pelo aparelho sobre a dentição. As demais variáveis não demostraram diferenças estatisticamente significativas. Conclusão: Houve mudanças estatisticamente significativas no posicionamento dos dentes, porém clinicamente sem relevância, com um tempo médio de uso de 6,47 meses do aparelho de avanço mandibular. Contudo, deve-se considerar que o uso dessa aparelhagem é comum durante longos períodos, fazendo com que seja de suma importância o acompanhamento desses pacientes a longo prazo.