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.

Posición del incisivo inferior en pacientes de clase esqueletal I y II según su biotipo facial en una muestra de una clínica privada, Cali 2014 - 2020 / Position of the lower incisor in patients of skeletal class I and II according to their facial biotype in a sample from a private clinic, Cali 2014 - 2020

Introducción: la sínfisis mentoniana es la articulación cartilaginosa medial de los huesos mandibulares, su posición se relaciona con los diferentes biotipos y puede influir en la posición del incisivo inferior. Objetivo: determinar si existen variaciones en la posición del incisivo inferior, en pacientes clase II con diferentes biotipos. Materiales y métodos: se evaluaron la totalidad de tomografías de pacientes clase I y II esquelética que asistieron entre 2014 y 2020 a una clínica privada, teniendo una muestra total de 74 pacientes, caracterizándolos por sexo y edad. Se determinó biotipo facial, Incisor Mandibular Plane Angle, distancias a la sínfisis como el ACV-ACL y altura desde el ápice. Para el análisis se utilizó I-CAT Visión Q, para las medidas de las tomografías digitales y para el análisis estadístico Stata 17. Resultados: se en- contró un Incisor Mandibular Plane Angle mayor en pacientes clase II en los tres biotipos; los dolicofaciales clase II mostraron menor valor en corticales ACV-ACL, los pacientes mostraron mayor proinclinación en la clase II. La posición del incisivo en pacientes clase II presenta una proinclinación significativa en braquifaciales (p = 0.04). Conclusión: se encontraron variaciones entre los tres biotipos faciales en las diversas mediciones en pacientes clase I y II, el sexo femenino evidenció diferencias significativas en las clases en las medidas del Incisor Mandibular Plane Angle y la altura de la sínfisis a nivel del ápice; estos hallazgos son relevantes en el momento de realizar un tratamiento ortodóntico ya que puede limitar el movimiento de los incisivos inferiores.

Introduction: the mental symphysis is the medial cartilaginous joint of the mandibular bones, its position is related with the different biotypes and can influence the position of the lower incisor. Objective: to determine if there are variations in the position of the lower incisor, in class II patients with different biotypes. Materials and methods: all the tomography of skeletal class I and II patients who attended a private clinic between 2014 and 2020 were evaluated, having a total sample of 74 participants, characterizing the patients by sex and age. Facial biotype, Incisor Mandibular Plane Angle, distances to the symphysis such as the ACV-ACL and height from the apex were determined. For the analysis, I-CAT Vision Q was used for the measurements of the digital tomography and for the statistical analysis Stata 17. Results: a greater Incisor Mandibular Plane Angle in class II patients in the three biotypes was evident; class II dolichofacials showed a lower value in both cortical ACV-ACL, with the narrowest and longest measurement of the symphysis, the patients showed proclination in class II for both sexes, being higher for the male. The position of the incisor within the symphysis in class II patients presents a significant proclination in brachyfacial patients (p=0.04), despite presenting greater proclination, it maintains its apices centered within the symphysis. Conclusion: variations were found between the three facial biotypes in class I and II patients, it is relevant when performing orthodontic treatment since it can limit the movement of the lower incisors.

Tratamiento de la transposición de incisivos inferiores / Treatment of transposition of lower incisors

La transposición es el intercambio de la posición de dos dientes adyacentes durante los primeros años de la dentición mixta. El objetivo de la investigación fue evaluar los cambios clínicos de un caso con transposición parcial bilateral de incisivos laterales mandibulares. Se atendió una paciente de 8 años de edad, femenina, de raza blanca, síndrome de Clase II división 1, con transposición de los incisivos laterales con caninos inferiores. Fue tratada con un arco lingual de cierre horizontal, de alambre 0,032 y dos muelles de NiTi comprimidos desde el cierre horizontal del arco hasta una armella soldada a la banda que se colocó en ambos incisivos laterales. Se recuperó el espacio necesario para la erupción de los caninos inferiores y así mejoró la estética dental y facial de la paciente.

Transposition is the exchange of the position of two adjacent teeth during the first years of the mixed dentition. The objective of this research is to evaluate the clinical changes of a case with partial bilateral transposition of mandibular lateral incisors. We present an 8-year-old white female patient with Class II Division 1 malocclusion and transposition of the lateral incisors with lower canines. She was treated with a 0.032 wire horizontal closure lingual arch and two NiTi springs compressed from the horizontal closure of the arch to an eyebolt welded to the band that was placed on both lateral incisors. The necessary space for the eruption of the lower canines was recovered, thus improving her dental and facial aesthetics.

Estimation of dental age using the kvaal method with digital panoramic radiographs in peruvian adults / Estimación de la edad dental según el método de Kvaal con radiografías panorámicas digitales en adultos peruanos

To determine the accuracy of the Kvaal method in the estimation of dental age through the analysis of digital panoramic radiographs of patients between 20 and 47 years of age who attended the stomatological clinic of the Universidad Científica del Sur, (2018 to 2019), Lima-Perú. 289 digital panoramic radiographs belonging to individuals of both sexes, aged 20 to 47 years were analyzed. Length and width measurements were obtained in the dental and pulp chamber in the upper central incisors. These data were subsequently evaluated by calculating the proportions between the pulp and root length of the upper central incisor by applying the formula of the method of Kvaal et al. to obtain the accuracy of the method in estimating dental age. Applying the formula of Kvaal et al. indicates that the relationship between the width of the pulp and the length of the root has a higher level of significance in relation to others proportions: M mean value of all ratios except T (-0.659) and W-L difference between W and L (-0.643). The coefficient of determination (r²) and standard error of estimation (SEE) using the original Kvaal formula is r²: 0.70, SEE: 4.90 years, then a modified Kvaal formula was proposed for the Peruvian population. The Method of Kvaal et al. has an accuracy of 1.24 in estimating the dental age of individuals, using the upper central incisor in digital panoramic radiographs.

Determinar la precisión del método de Kvaal en la estimación de la edad dental mediante el análisis de radiografías panorámicas digitales de pacientes entre 20 a 47 años atendidos en la clínica estomatológica de la Universidad Científica del Sur, (2018 a 2019), Lima-Perú. Se analizaron 289 radiografías panorámicas digitales pertenecientes a individuos de ambos sexos, de 20 a 47 años. Se obtuvo medidas de longitud y anchura en la cámara dental y pulpar en los incisivos centrales superiores. Estos datos se valoraron posteriormente al calcular las proporciones entre la pulpa y longitud de la raíz del incisivo central superior aplicando la fórmula del método de Kvaal et al. para obtener la precisión del método en la estimación de la edad dental. Al aplicar la fórmula de Kvaal et al. indica que la relación entre la anchura de pulpa y la longitud de la raíz presentan un nivel de significancia mayor en relación a otras proporciones: M valor medio de todas las proporciones excepto T (-0.659) y W-L: diferencia entre los valores de W y L (-0.643). El coeficiente de determinación (r²) y el error estándar de la estimación (SEE) utilizando la fórmula original de Kvaal es de r²: 0.70, SEE: 4.90 años, después se propuso una fórmula modificada de Kvaal para la población peruana. El Método de Kvaal et al. tiene una precisión del 1.24 en la estimación de la edad dental de los individuos, utilizando el incisivo central superior en radiografías panorámicas digitales.

Reabilitação estética e funcional com resina composta após trauma dentário: relato de caso / Aesthetic and functional rehabilitation with composite resin after dental trauma: case report

As lesões dentárias traumáticas são um problema de saúde pública mundial, dentre as quais a fratura dentária é a de maior ocorrência, envolvendo principalmente os dentes anteriores. A abordagem de grandes fraturas anteriores é um desafio para cirurgiões dentistas de qualquer nível pois, além da função, afetam diretamente a estética do paciente, fazendo-se necessário um planejamento que envolva diferentes especialidades na odontologia. Objetivo: Relatar um caso clínico de reabilitação funcional e estética de fratura dentária nos incisivos centrais superiores envolvendo tratamento endodôntico, instalação de pino de fibra de vidro e restauração direta em resina composta. Relato de Caso: O paciente de 17 anos sofreu fratura nos incisivos centrais superiores causada por uma queda de bicicleta. Devido à busca tardia por tratamento o elemento 21 foi diagnosticado com necrose pulpar e, portanto, foi submetido à tratamento endodôntico pela Técnica Crown Down e reabilitação com pino de fibra de vidro Splendor-SAP. Posteriormente, os elementos 11 e 21 foram restaurados com facetas diretas em resina composta pela técnica incremental. Conclusão: A reabilitação com instalação de pino de fibra de vidro associada à técnica de estratificação incremental em resina composta se mostra como uma boa opção para reabilitação estética pois permite dar forma anatômica ao dente com riqueza de detalhes na estratificação da dentina e esmalte, além de máxima preservação da estrutura dental. Os resultados obtidos reforçam o sucesso estético e funcional com significativo impacto na qualidade de vida do paciente(AU)

Traumatic dental injuries are a worldwide public health problem, among which dental fractures are the most frequent, mainly involving the anterior teeth. The approach of large anterior fractures is a challenge for dental surgeons of any level because, in addition to function, they directly affect the patient's esthetics, requiring a plan that involves different specialties in dentistry. Objective: Report a clinical case of functional and aesthetic rehabilitation of dental fractures in maxillary central incisors involving endodontic treatment, installation of a fiberglass post and direct restoration in composite resin. Case Report: The 17-year-old patient suffered a fracture in the upper central incisors caused by a fall from a bicycle. Due to the late search for treatment, element 21 was diagnosed with pulp necrosis and, therefore, underwent endodontic treatment using the Crown Down Technique and rehabilitation with a Splendor-SAP fiberglass pin. Later, elements 11 and 21 were restored with direct veneers in composite resin using the incremental technique. Conclusion: Rehabilitation with the installation of a fiberglass post associated with the incremental layering technique in composite resin is a good option for aesthetic rehabilitation as it allows the anatomical shape of the tooth with rich details in the layering of dentin and enamel, in addition to maximum preservation of the tooth structure. The results obtained reinforce the aesthetic and functional success with a significant impact on the patient's quality of life(AU)

Ethnic variation in the most common shade of anterior teeth among malaysian students: a cross-sectional study / Variación del tono más común de los dientes anteriores entre estudiantes malasios de diferentes etnias: un estudio transversal

Aim: Determination of the most common shade of anterior teeth in Malaysian students of different ethnicities. Materials and Methods: A total of 120 subjects, 40 each from different ethnicities (Malay, Chinese, and Indian) aged 18-22 years were evaluated for tooth shade using the VITA Classical shade guide. The subject was asked to sit in an up-right position with teeth at the clinician's eye level and the subject was instructed to remove makeup or tinted eyewear which may affect the result. The procedure was done in natural daylight. The shade tabs were positioned adjacent to the maxillary central incisor and the middle 1/3rd of the facial surface was assessed by experts to determine the correct tooth shade. The data was statistically analysed. Results: The differences in tooth shade were seen among the subjects of different ethnicities. The Malay ethnicity has B1 (37%) as the most common tooth shade whereas Chinese has C1 (27%) and Indian C1 (40%). Conclusions: Under the limitation of the study, it was found that there is a relationship between tooth color and ethnic background. Malay students tend to have brighter teeth as compared to Chinese and Indian students.

Objetivo: Determinar el tono más común de los dientes anteriores en estudiantes malasios de diferentes etnias. Materiales y Métodos: Se evaluó el color de los dientes de un total de 120 sujetos, 40 de diferentes etnias (malayos, chinos e indios) de edades comprendidas entre 18 y 22 años, utilizando la guía de colores VITA Classical. Se pidió al sujeto que se sentara en posición vertical con los dientes al nivel de los ojos del médico y se le indicó que se quitara el maquillaje o las gafas teñidas, lo que podría afectar el resultado. El procedimiento se realizó con luz natural. Las pestañas de color se colocaron adyacentes al incisivo central superior y expertos evaluaron el tercio medio de la superficie facial para determinar el tono correcto del diente. Los datos fueron analizados estadísticamente. Resultados: Se observaron diferencias en el color de los dientes entre los sujetos de diferentes etnias. La etnia malaya tiene el B1 (37%) como el color de dientes más común, mientras que los chinos tienen el C1 (27%) y los indios C1 (40%). Conclusión: Bajo las limitaciones del estudio, se encontró que existe una relación entre el color de los dientes y el origen étnico. Los estudiantes malayos tienden a tener dientes más brillantes en comparación con los estudiantes chinos e indios.

Asociación entre la inclinación sagital del incisivo central superior y el ángulo nasolabial en ortodoncia / Association between the sagittal inclination of the maxillary central incisor and the nasolabial angle in orthodontics

Objetivo: determinar si existe asociación entre la inclinación del incisivo central superior y el ángulo naso-labial de Legan. Materiales y métodos: se utilizaron las telerradiografías laterales de cráneo de 20 pacientes entre 18 y 39 años, obtenidas al inicio y final de su tratamiento ortodóncico, para un análisis cefalométrico. El total de medidas obtenidas se ordenó en dos tiempos. Tiempo 1 (T1) incluyó la medición del ángulo plano biespinal-eje mayor del incisivo superior (AiT1) y del ángulo naso-labial (AnlT1) en las radiografías tomadas previo al tratamiento y tiempo 2 (T2) incluyó la medición de los mismos ángulos en las radiografías tomadas al finalizar el tratamiento (AiT2 y AnlT2 respectivamente). Los datos obtenidos fueron tabulados y analizados estadísticamente. Resultados: la muestra presentó distribución normal, por lo que se aplicó el test de correlación de Pearson, para determinar si existía asociación entre ambas variables (Ai y Anl) en T1 y T2, obteniendo como resultado un valor de R=0,5. Conclusión: no existe asociación estadística entre la variación en la inclinación del incisivo central superior y el Ángulo naso-labial de Legan.

Aim: to determine if there is an association between the inclination of the upper central incisor and the nasolabial Legan angle. Materials and methods: lateral head radiographs of 20 patients between 18 and 39 years old, obtained at the beginning and end of their orthodontic treatment, were used for a cephalometric analysis. The total of measurements obtained was ordered in two times. Time 1 (T1) included the measurement of the bispinal plane angle-major axis of the upper incisor (AiT1) and the nasolabial angle (AnlT1) in the radiographs taken before treatment and time 2 (T2) included the measurement of the same angles, in the radiographs taken at the end of the treatment (AiT2 and AnlT2 respectively). The data obtained were tabulated and statistically analyzed. Results: the sample presented a normal distribution. So, the Pearson correlation test was applied to determine if there was an association between both variables (Ai and Anl) in T1 and T2, obtaining a value of R=0.5 as a result. Conclusion: there is no statistical association between the variation in the inclination of the upper central incisor and the nasolabial Angle of Legan.

Evaluation of the incisive canal using cone beam computed tomography

The incisive canal is innervated by the nasopalatine nerve and irrigated by the anterior branches of the descending palatine vessels, the sphenopalatine and greater palatine artery. Sometimes, the incisor canal interferes with the placement of implants or other surgical procedures, it is necessary to resort to previous treatments in order to have the ideal conditions in the area to be treated and avoid complications. Methods: 100 cone beam computed tomography were studied evaluating the diameter, length and shape of the incisor canal, distance from the lower edge of the incisor canal to the alveolar ridge, length and width of the bone anterior to the incisor canal, and width of the palatal bone. Results and conclusions: The variables that showed a statistically significant difference comparing between male and female patients were vestibulo-palatal and incisor foramen diameter, incisor canal length, distance from the canal to the central incisor, coronal and medial width of the vestibular bone; and the width of the palatal bone at apical and mid-level; being greater in male patients.

Oclusión basada en evidencia: rompiendo paradigmas / Occlusion based on evidence: breaking paradigms

La odontología basada en evidencias es una metodología que busca que las decisiones clínicas diarias que toman los profesionales en estomatología se encuentren fundamentadas en la evidencia científica, en ella se integran las experiencias clínicas, las necesidades, las preferencias del paciente y la evidencia clínicamente relevante más actual analizada por pares. Estos pilares son parte del proceso en la toma de decisiones para la atención al paciente. La odontología basada en evidencias surge de las exitosas experiencias obtenidas con el desarrollo e implementación de la medicina fundamentada en pruebas, al aplicar el método científico en la evaluación, planificación y toma de decisiones de las prestaciones sanitarias, sobre todo a través de los estudios controlados. En general, toda la práctica odontológica ha tenido grandes avances basados en evidencias, con hechos verídicos comprobados, pero los conceptos fundamentales de oclusión no han tenido una mejora cimentada en el conocimiento científico, prueba de ello es que se siguen ocupando teorías y conceptos de las filosofías de oclusión en la rehabilitación de muchos pacientes, seguimos creyendo en mitos y sofismas que no han podido ser demostrados. En esta revisión, demostramos los grandes avances en los conceptos de oclusión e invitamos a todos los odontólogos a romper los paradigmas de la oclusión antigua sin evidencias científicas y a utilizar las herramientas del método científico en la práctica clínica odontológica (AU)

Evidence-based dentistry is a strategy that seeks to ensure that the daily clinical decisions made by the dental professional are based on scientific evidence. It integrates the clinical experience of the dentist, the needs and preferences of the patient, and the most current relevant clinical evidence. All three are part of the decision-making process for patient care. Evidence-based dentistry arises from the successful experiences obtained with the development and implementation of evidence-based medicine, applying the scientific method in the evaluation, planning and decision-making of health benefits, especially through controlled studies. In general, all dental practice has had great advances based on evidence, with proven true facts, but the fundamental concepts of occlusion have not had an improvement based on scientific knowledge, proof of this is that theories and concepts continue to be used. of the philosophies of occlusion in patient rehabilitation, we follow myths and sophisms that have not been demonstrated, in this review, we demonstrate the great advances in the concepts of occlusion and we know all dentists to break the paradigms of the old occlusion without scientific evidence (AU)

Interdisciplinary treatment to replace missing upper lateral incisors, 4.5 years follow up / Tratamiento interdisciplinario para reposición de incisivos laterales superiores faltantes, seguimiento de 4,5 años

Introduction: Multidisciplinary diagnosis and planning are essential to define the treatment option that will provide the best individual results for patients with congenitally missing upper lateral incisors. Objective: To determine the function and aesthetics after the therapeutic use of osseintegrated implants to replace congenitally missing upper lateral incisors in a young female at 4.5 years follow-up. Case report: The patient was a 13 years old female (at beginning of treatment) with congenitally missing upper lateral incisors condition. Five months after the orthodontic active treatment, the space for placing the implants was achieved. After 2 years of Orthodontic treatment and the evaluation of the craniomandibular growth term by hand radiography, two implants were placed with an expanded bone technique in the position of the upper lateral incisors. After 4 months, osseointegration was clinically confirmed and two screw retained temporary crowns were performed using temporary plastic abutments and acrylic teeth and recalled at 4.5 years to control. Conclusions: Our results showed predictable esthetics and functional results in a patient with congenitally missing upper lateral incisors. This was possible due to a multidisciplinary approach between the diagnosis and treatment performed (Orthodontics, Implantology and Prosthodontics(AU)

Introducción: El diagnóstico y la planificación multidisciplinarios son esenciales para definir la opción de tratamiento que proporcionará los mejores resultados individuales para los pacientes con incisivos laterales superiores que faltan congénitamente. Objetivo: Fue determinar la función y la estética después del uso terapéutico de implantes osteointegrados para reemplazar los incisivos laterales superiores ausentes congénitamente en una mujer joven a los 4,5 años de seguimiento. Presentación del caso: La paciente, mujer de 13 años (al inicio del tratamiento) con una condición congénita de incisivos laterales superiores ausentes. Cinco meses después del tratamiento activo de ortodoncia, se logró el espacio para la colocación de los implantes. Después de 2 años de tratamiento de Ortodoncia y la evaluación del término de crecimiento cráneo-mandibular corroborado mediante radiografía de mano, se colocaron dos implantes con técnica de hueso expandido en la posición de los incisivos laterales superiores. Después de 4 meses, se confirmó clínicamente la osteointegración y se realizaron dos coronas provisionales atornilladas utilizando pilares de plástico provisionales y dientes acrílicos y se controlaron a los 4,5 años de seguimiento. Conclusiones: Nuestros resultados mostraron resultados estéticos y funcionales predecibles en un paciente con incisivos laterales superiores ausentes congénitamente. Esto fue posible gracias a un abordaje multidisciplinar entre el diagnóstico y el tratamiento realizado (Ortodoncia, Implantología y Prostodoncia(AU)

A new approach to endodontic access in anterior teeth: a pilot study / Uma nova abordagem para acesso endodôntico em dentes anteriores: estudo piloto

Introduction: The coronal opening is essential, during endodontic treatment, for direct access to the root canals. Usually, in the anterior teeth, endodontic access is achieved on the palatal/lingual surface, more specifically in the cingulum region. However, the lack of observation for dental positioning can lead to some accidents and complications, such as buccal perforations, causing esthetic damage and compromising the treatment. Objective: To evaluate the applicability of a new approach for performing coronal opening in anterior teeth, regarding the wear caused on the tooth crown, and to evaluate the ease of performing the new technique to minimize the risk of perforation. Material and method: Ten students (n=10) from the Improvement in Endodontics program participated in the present study. Twenty artificial teeth were used, which were upper, central incisors. Each participant performed two coronal openings. First, with no guidance (Group A - Conventional Technique) and afterward, a new opening, but with guidance with the spherical diamond tip placed parallel to the long axis of the tooth (Group B - Modified Technique). Result: The results showed that 90% of the participants considered the Modified Technique as having lower risk of accidents, as well as being easier for locating the pulp chamber. There was a statistical difference both in the measurement of the total area of wear and in the width, while there was no statistical difference in the height. Conclusion: Preliminary data collected with the survey were satisfactory for the Modified Technique. Statistically, it showed a favorable difference in relation to the area of wear and the width. However, in height there was no statistical difference.

Introdução: A abertura coronária é fundamental durante o tratamento endodôntico para um acesso direto aos canais radiculares. Em geral, em dentes anteriores, o acesso endodôntico é realizado na face palatina/lingual, mais especificamente em região de cíngulo. Entretanto, a falta de observação do posicionamento dentário pode levar a alguns acidentes e complicações, como as perfurações por vestibular, ocasionando dano estético e comprometendo o tratamento. Objetivo: Avaliar a aplicabilidade de uma nova abordagem de realização da abertura coronária em dentes anteriores, quanto ao desgaste ocasionado na coroa dentária, e avaliar a facilidade de execução da nova técnica para minimizar os riscos de perfurações. Material e método: Dez alunos (n=10) do curso de Aperfeiçoamento em Endodontia participaram do estudo. Foram utilizados vinte dentes artificiais, sendo eles incisivos centrais superiores. Cada participante realizou duas aberturas coronárias. Primeiramente sem nenhuma orientação (Grupo A - Técnica Convencional) e após, uma nova abertura, porém com orientação, com a ponta diamantada esférica posicionada paralelamente ao longo eixo do dente (Grupo B - Técnica Modificada). Resultado: Os resultados demonstraram que 90% dos participantes consideraram a Técnica Modificada como a de menor risco de acidentes e, ainda, de mais fácil localização da câmara pulpar. Houve diferença estatística tanto para a medida da área total de desgaste quanto para a largura, enquanto na altura não houve diferença estatística. Conclusão: Os dados preliminares coletados pelo questionário se mostraram satisfatórios para a Técnica Modificada. Estatisticamente, apresentou diferença favorável em relação à área de desgaste e largura, já em altura não houve diferença estatística.

A long-term evaluation of periodontal phenotypes before and after the periodontal-orthodontic-orthognathic combined treatment of lower anterior teeth in patients with skeletal Angle class Ⅲ malocclusion / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the changes of periodontal phenotype (width of keratinized gingiva, thickness and height of alveolar bone) of lower anterior teeth in patients with skeletal class Ⅲ malocclusion before and after the periodontal-orthodontic-orthognathic combined treatment.@*METHODS@#In the study, 20 patients with skeletal class Ⅲ malocclusion (6 males and 14 females) completed the periodontal-orthodontic-orthognathic combined treatment were included from March 2017 to June 2022, with 39 central incisors, 40 lateral incisors and 40 canines. The mean age was (25.40±4.27) years (20-34 years). The mean follow-up time was (3.70±1.05) years from the beginning of periodontal corticotomy regenerative surgery (PCRS) to the end of the combined treatment. Cone-beam computed tomography (CBCT) was used to measure the thickness, area and height of alveolar bone by the same researcher, taken before the PCRS (T0), 6 months after the PCRS (T1), 12 months after the PCRS (T2), before the orthognathic surgery (T3), and after the periodontal-orthodontic-orthognathic combined treatment (T4). The periodontal clinical parameters were used to evaluate changes in the soft tissue by another researcher, measured before the PCRS (T0) and after the combined treatment (T4). Changes of soft and hard tissue were evaluated by the periodontal phenotype.@*RESULTS@#The width of keratinized gingiva increased significantly (all P < 0.001) in lower anterior teeth, the central incisors, lateral incisors and canines increased by (1.82±1.57) mm, (2.03±1.48) mm and (2.05±1.27) mm, respectively. The proportion of thick periodontal biotype in the central and lateral incisors increased significantly (all P < 0.001), while the changes of periodontal biotypes in the lower canines were not obvious. The thickness of labial alveolar bone of lower anterior teeth all increased significantly after periodontal corticotomy regenerative surgery and the combined treatment (all P < 0.001). The area of labial alveolar bone of lower anterior teeth also increased significantly after the combined treatment (all P < 0.001). The whole area of labial and lingual alveolar bone of central and lateral incisors increased (P < 0.001), while the whole area of canines remained the same. All The height of the alveolar bone increased (all P < 0.001) on the labial side after the treatment.@*CONCLUSION@#The periodontal phenotypes of lower anterior teeth were significantly improved after the periodontal-orthodontic-orthognathic combined treatment in patients with skeletal Angle class Ⅲ malocclusion. The improvement was long-termly stable, and the periodontal risk was reduced.

Decompensation effectiveness and alveolar bone remodeling analysis of mandibular anterior teeth after preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusion / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the decompensation effectiveness and alveolar bone remodeling of mandibular anterior teeth after preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusion using lateral cephalogram and cone-beam computed tomography (CBCT).@*METHODS@#Thirty high-angle patients with skeletal class Ⅱ malocclusion who had received preoperative orthodontic treatment and orthognathic surgery in Peking University School and Hospital of Stomatology between Ja-nuary 2017 and August 2022 and had taken lateral cephalogram and CBCT before and after preoperative orthodontic treatment were selected. Items were measured with lateral cephalogram including: The lower central incisor (L1)-Frankfort plane angle (L1-FH), the L1-mandibular plane angle (L1-MP), the L1-nasion-supramental angle (L1-NB) and the vertical distance from the incisal edge of lower central incisor to NB line (L1-NB distance), etc. The incidence of dehiscence/fenestration and the length of dehiscence at labial side (d-La) and lingual side (d-Li) were measured using CBCT. Pearson correlation analysis was used to evaluate the correlation between the changes of d-Li of L1 and age, duration of preoperative orthodontic treatment and the cephalometric measurements before preoperative orthodontic treatment to screen out risk factors affecting the periodontal risk of preoperative orthodontic treatment in high-angle patients with skeletal class Ⅱ malocclusions.@*RESULTS@#After preoperative orthodontic treatment, L1-FH, L1-MP, L1-NB and L1-NB distances changed by 11.56°±5.62°, -11.13°±5.53°, -11.57°±5.43° and (-4.99±1.89) mm, respectively, and the differences were all statistically significant (P < 0.05). Among the 180 measured mandibular anterior teeth, 45 cases with labial dehiscence/fenestration before preoperative orthodontic treatment (T0) had no longer labial dehiscence/fenestration after preope-rative orthodontic treatment (T1); 142 cases without lingual dehiscence/fenestration at T0 had lingual dehiscence/fenestration at T1. After preoperative orthodontic treatment, the d-La of lower lateral incisors (L2), lower canines (L3) and lower anterior teeth (L1+L2+L3) decreased by (0.95±2.22) mm, (1.20±3.23) mm and (0.68±2.50) mm, respectively, and the differences were statistically significant (P < 0.05); the d-Li of L1, L2, L3 and L1+L2+L3 increased by (4.43±1.94) mm, (4.53±2.35) mm, (3.19±2.80) mm and (4.05±2.46) mm, respectively, and the differences were statistically significant (P < 0.05). The increase of d-Li of L1 was positively correlated with L1-FH (r=0.373, P=0.042).@*CONCLUSION@#This study showed that high-angle patients with skeletal class Ⅱ ma-locclusion could achieve ideal decompensation effect of mandibular anterior teeth after preoperative orthodontic treatment with bilateral mandibular first premolars extracted, but the lingual periodontal risk of mandibular anterior teeth was increased. This risk could be correlated to L1-FH before preoperative orthodontic treatment, which should be paid more attention in the design of orthodontic-orthognathic surgical treatment.

Prediction, analysis and application of learning curve of tooth preparation for all ceramic crowns of maxillary central incisors / 北京大学学报(医学版)

OBJECTIVE@#To predict the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training based on the modified Wright learning curve model, then to analyze and applicate the learning curve.@*METHODS@#Twelve graduate students participating in standardized dental resident training were selected to prepare the resin maxillary central incisors on phantom head simulators for all ceramic crowns 4 times. The results of preparation were evaluated by 3 prosthetic experts with at least 10 years' experience focusing on the reduction, contour, taper, shoulder, finish line, margin placement, adjacent tooth injury, and preparation time for tooth preparation. The learning rate of tooth preparation was calculated by scores of tooth preparation of 4 times. The learning curve of tooth preparation was predicted based on the modified Wright learning curve model. According to the criteria of standardized training skill examinations for dental residents in Beijing, 80 was taken as the qualified standard score. The minimum training times for tooth preparation to satisfy the qualified standard score (80) was calculated, to analyze the characteristics of learning curve and evaluate the effectiveness of tooth preparation.@*RESULTS@#The scores of 4 tooth preparation were 64.03±7.80, 71.40±6.13, 74.33±5.96, and 75.98±4.52, respectively. The learning rate was (106±4)%, which showed the learning curve an upward trend. There were no significant differences between the qualified standard score and the predicted scores of tooth preparation from the 5th preparation to the 13th preparation (P > 0.05). The predicted score of the 14th preparation was higher than the qualified standard score (P < 0.05).@*CONCLUSION@#The trend of the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training is upward, which predicts the minimum training times higher than the qualified standard score is 14 times.

Multi-disciplinary treatment of severe palatal radicular groove of maxillary lateral incisor: A case report and literature review / 中南大学学报(医学版)

Palatal radicular groove is a developmental malformation of maxillary incisors, lateral incisors in particular, which often causes periodontal destruction. This paper reports a case of combined periodontal-endodontic lesions induced by palatal radicular groove, which was initially misdiagnosed as a simple periapical cyst. After root canal therapy and periapical cyst curettage, the course of disease was prolonged, resulting in the absence of buccal and maxillary bone plates in the affected tooth area. After the etiology was determined, the affected tooth was extracted and guide bone tissue regeneration was performed at the same time, followed by implantation and restoration at the later stage, leading to clinical cure. The palatal radicular groove is highly occult, and the clinical symptoms are not typical. If the abscess of the maxillary lateral incisor occurs repeatedly, and the abscess of the maxillary lateral incisor has not been cured after periodontal and root canal treatment, cone-beam computed tomographic and periodontal flap surgery should be considered.

Clinical analysis of patients with oral and maxillofacial infections in oral emergency / 北京大学学报(医学版)

OBJECTIVE@#To analyze the composition, incidence and clinical characteristics of oral and maxillofacial infections in oral emergency.@*METHODS@#A retrospective study on patients with oral and maxillofacial infections who visited the Department of Oral Emergency in Peking University School and Hospital of Stomatology from January 2017 to December 2019 was conducted. General characteristics, such as disease composition, gender, age distribution and position of involved teeth were analyzed.@*RESULTS@#A total of 8 277 patients with oral and maxillofacial infections were finally collected, including 4 378 male patients (52.9%) and 3 899 female patients (47.1%), with gender ratio of 1.12:1. The common diseases were periodontal abscess (3 826 cases, 46.2%), alveolar abscess (3 537 cases, 42.7%), maxillofacial space infection (740 cases, 9.0%), sialadenitis (108 cases, 1.3%), furuncle & carbuncle (56 cases, 0.7%) and osteomyelitis (10 cases, 0.1%). Male patients were more easily affected by periodontal abscess, space infection and furuncle & carbuncle than female patients with the gender ratios 1.24:1, 1.26:1, 2.50:1 individually, while the incidence of alveolar abscess, sialadenitis, furuncle & carbuncle had no significant gender difference. Different diseases were prone to occur at different ages. The peak ages of alveolar abscess were 5-9 and 27-67 years, while the peak age of periodontal abscess was 30-64 years. Space infection tended to occur between 21-67 years. There were 7 363 patients with oral abscess (3 826 patients with periodontal abscess and 3 537 patients with alveolar abscess), accounting for 88.9% of all the patients with oral and maxillofacial infections, involving 7 999 teeth, including 717 deciduous teeth and 7 282 permanent teeth. Periodontal abscess usually occurred in permanent teeth, especially the molar teeth. Alveolar abscess may occur in both primary teeth and permanent teeth. In primary teeth, the most vulnerable sites were primary molar teeth and maxillary central incisors while in permanent teeth the most vulnerable sites were first molar teeth.@*CONCLUSION@#Understanding the incidence of oral and maxillofacial infection was conducive to the correct diagnosis and effective treatment of clinical diseases, as well as targeted education for patients of different ages and genders to prevent the occurrence of diseases.

Clinical decision making of implant guidance methods guided by new classification of surgical area mouth ope-ning / 华西口腔医学杂志

When selecting implant guidance methods or judging whether the patient can be implanted, many doctors ignore or only use visual inspection to estimate a patient's mouth opening. This phenomenon often leads to failure to complete the implantation due to insufficient mouth opening or the deflection of the implant due to limited angle, resulting in the high incidence of corresponding complications. The main reason is that doctors lack accurate analysis and control of the overall geometric conditions of the intraoral surgical area, and three-dimensional position blocking of surgical instruments occurs during the operation. In the past, mouth opening was defined as the distance between the incisor edges of the upper and lower central incisors when the patient opens his mouth widely, and the implant area could be in any missing tooth position. When it is in the posterior tooth area, the specific measurement scheme of the mouth opening could not be simply equivalent to the previous measurement method in the anterior tooth area. However, how to measure quickly and conveniently the mouth opening of any surgical area to determine whether it could be implanted and meet the needs of the selected guidance method remains unclear. This paper introduces new concepts, establishes new classification and corresponding accurate measurement scheme of implant area, and establishes a decision tree of implant methods guided by the actually measured value. Results provide a quantitative basis for rational formulation and implementation of implant treatment.

Effect of dental follicles in minimally invasive open-eruption technique of labially impacted maxillary central incisors / 华西口腔医学杂志

OBJECTIVES@#To summarize the open-eruption technique of impacted anterior maxillary teeth, this study reports a technically improved operation on surgical exposure based on dental follicles and evaluates post-treatment periodontal health considering the effect of dental follicles.@*METHODS@#Patients who underwent open-eruption technique with unilateral labially impacted maxillary central incisors were selected. The impacted teeth were assigned to the experimental group, and the contralateral unimpacted maxillary central incisors were assigned to the control group. In the surgical exposure, the new technique makes use of dental follicles to manage the soft tissue, so as to preserve soft tissue for better aesthetic results and healthier periodontal tissue. Tooth length, root length, alveolar bone loss, and alveolar bone thickness were recorded after the therapy.@*RESULTS@#A total of 17 patients with unilateral maxillary central incisor impaction were successfully treated. The tooth length and root length of the two groups showed a statistically significant difference between the impacted and homonym teeth, with a shorter length in the impacted tooth (P<0.05). More labial alveolar bone loss was found in the experimental group compared with that in the control group (P<0.05). The outcomes of the cementoenamel junction width, pa- latal alveolar bone loss, and alveolar bone thickness did not indicate statistical significance between the experimental and control groups (P>0.05).@*CONCLUSIONS@#In the surgical exposure, the new technique uses dental follicles to manage the soft tissue and preserve it for better aesthetic results and healthier periodontal tissues.

Root canal treatment of type Ⅱ and ⅢA double dens invaginatus in maxillary lateral incisor: a case report / 华西口腔医学杂志

Dens invaginatus is a rare developmental anomaly of the teeth that is caused by the infolding of enamel organs or the penetration of their proliferations into dental papillae before calcification has occurred. The presence of double dens invaginatus is extremely rare. This paper describes the use of cone beam computed tomography in the evaluation of a maxillary lateral incisor with double dens invaginatus and periapical periodontitis. The tooth was treated through microscopic root canal therapy. The tooth was free of clinical symptoms, and the periradicular lesion narrowed during the follow-up period of 1 year.

Cognition about emergency management of avulsed incisor in children among dentists in Guangdong province / 华西口腔医学杂志

OBJECTIVES@#This study aimed to evaluate and analyze the current situation of dentists in Guangdong pro-vince regarding the management of avulsed incisors, thereby providing a reference for making treatment strategies for avulsed incisors in the future.@*METHODS@#A total of 712 dentists with different educational backgrounds and working conditions in Guangdong province were randomly selected to conduct an online questionnaire survey on the cognition of children with avulsed incisors from April 2022 to May 2022. The data were recorded by Excel software and statistics were analyzed on Stata/SE 15.1.@*RESULTS@#A total of 712 dentists were investigated and 701 questionnaires were collected (98.46%). In addition, 65.9% of investigators came from the Department of Stomatology in a First-class Hospital or Stomatological Hospital. The results showed that the average number of avulsed teeth consulted by dentists was less than 20 per year. Although 99.7% of respondents considered normal saline as a suitable storage medium, 3.1% and 23.8% of them had a misunderstanding that the tap/alcohol could be used for root cleaning. Moreover, 93.4% was the correct selection rate of the treatment plan for processing on root surfaces before replanting by investigators. The correct selection rate of the duration using elastic fixation was only 10.7%. Meanwhile, 42.9% of investigators refused to inoculate tetanus immunoglobulin after teeth replanting. Emergency management of dental avulsion (EM) and clinical management of dental avulsion (CM) answered correctly with average scores of 14.60±11.85 and 14.48±2.67, respectively. Multivariate linear regression analysis revealed that working years were negatively correlated with EM and CM scores (P<0.05). There was a positive correlation between CM and EM scores with the number of avulsion cases treated by physicians each year (P<0.05). In terms of the EM score of dentists' learning attitude, investigators who had received enough knowledge were higher than those who had not and insufficient knowledge reserved, and the difference was statistically significant (P<0.05). The scores of investigators who thought they had a certain degree of knowledge about dental trauma were higher than those who thought they "did not understand", and the difference was statistically significant (P<0.05). In terms of CM scores, investigators who thought the knowledge of dental trauma was "very helpful" had higher scores than those who thought it was "not helpful", and the difference was statistically significant (P<0.05). The scores of the investigators who thought they had "relatively sufficient knowledge" of dental trauma were higher than those who thought they had "no knowledge" or "insufficient know-ledge", and the difference was statistically significant (P<0.05).@*CONCLUSIONS@#The overall accuracy of the management of avulsed incisors among dentists was low in Guangdong province. Dentists were more likely to have a higher rate of accuracy choice in treatment options for luxation injury and avulsion to enhance the prognosis of replanted teeth.