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)

El canal incisivo: ¿maxilar o mandibular? Revisión narrativa / The incisive canal: a maxillary or mandibular structure? Narrative review

El canal incisivo es una estructura anatómica ósea que, según la terminología anatómica actual, se encuentra ubicada exclusivamente en la premaxila. Sin embargo, a continuación de los canales mandibulares, se desprenden hacia lateral los canales mentonianos (que contiene el paquete vasculonervioso del mismo nombre) y hacia anterior continua un paquete vasculonervioso, también denominado incisivo que inerva e irriga a dichos dientes mandibulares. Con el fin de aclarar lo previamente mencionado y distinguir ambas estructuras incisivas, se pretende agregar un sufijo (maxilar o mandibular) rectificando los nombres de dichos canales. Para lo anterior, se realizó una revisión de la bibliografía disponible en PubMed y Google Académico, con las palabras clave "CANAL INCISIVO" e "INCISIVE CANAL", utilizando como operador booleano la palabra OR. Los criterios de inclusión de los estudios fueron: 1) que se refieran a algún canal incisivo (ya sea maxilar o mandibular) 2) que estén disponibles para ser leídos a texto completo y 3) que su idioma sea inglés o español. De la totalidad de los artículos analizados, un 52 % hablaba exclusivamente del canal incisivo maxilar, un 43 % solo del canal incisivo mandibular y un 5 % sobre ambos. Concluyendo, podemos colegir que es de suma importancia que se regularice la nomenclatura de dichas estructuras anatómicas, debido a que, el hecho de reconocerla como tal permite garantizar su estudio y aporte desde toda la comunidad científica, sin importar la procedencia ni el idioma. Además, el canal incisivo mandibular está bien documentado, por lo que, al no ser reconocido en la terminología anatómica, se pierde la principal misión de la asociación internacional de asociaciones de anatomía (IFAA), la cual es unificar y organizar los nombres de las estructuras anatómicas existentes.

SUMMARY: The incisive canal is an anatomical bone structure that, according to current anatomical terminology, is located exclusively in the premaxilla. However, following the mandibular canals, the mental canals (containing the neurovascular bundle of the same name) branch off laterally and a neurovascular bundle continues anteriorly, also called the incisor, which innervates and irrigates said mandibular teeth. In order to clarify what was previously mentioned and to distinguish both incisive structures, it is intended to add a suffix (maxillary or mandibular) correcting the names of said canals. For the above, a review of the literature available in PubMed and Google Scholar was carried out, with the keywords "INCISIVE CANAL" and "INCISIVE CANAL", using the word OR as a boolean operator. The inclusion criteria of the studies were: 1) that they refer to an incisive canal (whether maxillary or mandibular) 2) that they be available to be read in full text and 3) that their language be English or Spanish. Of all the articles analyzed, 52% spoke exclusively about the maxillary incisive canal, 43% only about the mandibular incisive canal, and 5% about both. In conclusion, we can infer that it is of the utmost importance that the nomenclature of these anatomical structures be regularized, because the fact of recognizing it as such allows guaranteeing its study and contribution from the entire scientific community, regardless of origin or language. In addition, the mandibular incisive canal is well documented, therefore, by not being recognized in anatomical terminology, the main mission of the international association of anatomy associations (IFAA) is lost, which is to unify and organize the names of the anatomy. existing anatomical structures.

Inter-incisive index in Bulgarians and its application in dentistry / Indice interincisivo en búlgaros y su aplicación en odontología

SUMMARY: In recent years, aesthetic dentistry has become a major focus for the public. Facial attractiveness plays a key role on modern society and the creation of harmonious smile is an aim for every dentist. The objective of this study was to define certain values of the inter-incisive index in Bulgarians, the sexual dimorphism and bilateral asymmetry and to verify differences of this index between Bulgarians and other Balkan populations. The present study included 121 males and 111 females of Bulgarian origin aged 20- 40 years. Mesiodistal dimensions of maxillary central and lateral incisors were measured by Dentistry Sliding Vernier Caliper. We used the technique of direct anthropometry, modified by Prof. Y. Yordanov. We calculated the inter-incisive index as ratio of the mesiodistal dimension of maxillary lateral incisor to the mesiodistal dimension of the maxillary central incisor. The measurements were analyzed with SPSS 23. The level of statistical significance was set at P< 0.05. The inter-incisive index showed no statistically significant differences between left and right side of the dental arch in both sexes. We did not find statistically significant differences between males and females as well. On the other hand, we found statistically significant differences in MD values of incisors between Bulgarians and other Balkan nations. Inter-incisive index shows no sexual dimorphism and bilateral asymmetry in Bulgarians. This can be helpful in aesthetic dentistry, in prosthodontics and in orthodontic treatment planning.

RESUMEN: En los últimos años, la odontología estética se ha convertido en un foco importante para el público. El atractivo facial juega un papel clave en la sociedad moderna y la creación de una sonrisa armoniosa es importante para todos los dentistas. El objetivo de este estudio fue definir ciertos valores del índice interincisivo en búlgaros, el dimorfismo sexual y la asimetría bilateral y verificar diferencias de este índice entre búlgaros y otras poblaciones balcánicas. El presente estudio incluyó a 121 hombres y 111 mujeres de origen búlgaro entre 20 y 40 años de edad. Las dimensiones mesiodistales de los incisivos superiores centrales y laterales se midieron con un calibrador Vernier deslizante de odontología. Utilizamos la técnica de antropometría directa, modificada por el Prof. Y. Yordanov y se calculó el índice interincisivo como la relación entre la dimensión mesiodistal del incisivo lateral superior y la dimensión mesiodistal del incisivo central superior. Las medidas se analizaron con SPSS 23. El nivel de significancia estadística se fijó en P<0,05. El índice interincisivo no mostró diferencias estadísticamente significativas entre los lados izquierdo y derecho de la arcada dentaria en ambos sexos. Tampoco encontramos diferencias estadísticamente significativas entre hombres y mujeres. Por otro lado, encontramos diferencias estadísticamente significativas en los valores de DM de los incisivos entre búlgaros y otras naciones balcánicas. El índice interincisivo no muestra dimorfismo sexual ni asimetría bilateral en los búlgaros. Esto puede ser útil en odontología estética, en prostodoncia y en la planificación de tratamientos de ortodoncia.

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.

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.

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.

Prediction of the mesiodistal width of maxillary anterior teeth from nasal interalar width in peruvian subjects with facial harmony

Objective: To determine regression models to predict the mesiodistal widths of the maxillary anterior teeth from interalar width of the nose in subjects with facial harmony. Materials and Methods: A cross-sectional study was carried out in a sample of 75 subjects with facial harmony and ages ranging from 18 to 30 years (21.28±3.75 years). The mesiodistal width of the central (CI), lateral (LI) incisors, and canines (C), as well as the interalar width (IW) of each subject were measured using a digital vernier caliper. Simple linear regression analyses were used to predict the width of the maxillary anterior teeth from the nasal interalar width, from which formulas for predicting the dimensions of each anterior tooth were obtained. Results: A statistically significant relationship was found between the nasal interalar width and the mesiodistal widths of the upper central incisor (p=0.019, R2=5.23%), upper lateral incisor (p=0.019, R2=2.31%), and upper canine (p=0.016, R2=12.04%) that allowed to develop simple linear prediction models for each tooth represented by the following formulas: CI=7.04+0.04(IW); LI=6.01+0.03 (IW); C=6.19+0.05 (IW). Conclusion: The nasal interalar width is a good predictor of the mesiodistal widths of the maxillary anterior teeth.

Objectivo: Determinar modelos de regresión para predecir los anchos mesiodistales de los dientes anterosuperiores a partir del ancho interalar de la nariz en individuos con armonía facial. Materiales and Métodos: Se realizó un estudio transversal con una muestra de 75 sujetos con armonía facial entre 18 a 30 años (21.28 ± 3.75 años), se midió el ancho mesiodistal de incisivos centrales (IC), laterales (IL) y caninos (C) así como el ancho interalar (AI) de cada sujeto empleando un calibrador vernier digital. Para la predicción del ancho de los dientes anterosuperiores a partir del ancho interalar nasal se emplearon análisis de regresión lineal simple, a partir de los cuales se obtuvieron fórmulas de predicción de las dimensiones de cada pieza dentaria anterior. Resultados: Se encontró relación estadísticamente significativa entre el ancho interalar nasal y los anchos mesiodistales del incisivo central superior (p=0.019, R2 5.23%), incisivo lateral superior (=0.019, R2=2.31%) y canino superior (p=0.016, R2=12.04%) que permitieron generar modelos de predicción lineal simple para cada pieza dentaria representados mediante las siguientes fórmulas: IC=7.04+0.04(AI); IL=6.01+0.03(AI); C=6.19+0.05(AI). Conclusión:El ancho interalar nasal es un buen predictor de los anchos mesiodistales de los dientes anterosuperiores.

Prevalence of Molar Incisor Hypomineralisation Among School Children aged 7-12 years in Tunis, Tunisia

Abstract Objective: To evaluate the prevalence and the characteristics of Molar Incisor Hypomineralisation (MIH) in 7-12-year-old children in Tunis, Tunisia. Material and Methods: This study was designed as a cross-sectional study, in which school children aged 7 to 12 years were included. A total of 510 children (257 girls and 253 boys) who had their first permanent molar and incisors were evaluated using the 2003 European Academy of Paediatric Dentistry (EAPD) recommendation criteria were examined. Descriptive data analysis and Pearson's chi-squared test were performed (p<0.05). Results: A total of 510 children were included in the study. MIH was present in 35.4 % of our study population. Boys exhibited slightly higher MIH (19,4%) and Post Eruptive Breakdown (PEB) (7,3%) prevalence compared to girls, but the difference was not statistically significant (p=0.07). Moreover, demarcated opacities were more prevalent than PEB. More precisely, the main prevalence without PEB was MIH with white/creamy demarcated opacities, which was more frequent than yellow/brown demarcated opacities (p<0.05). Conclusion: The prevalence of MIH in Tunis was 35.4%, with no difference between girls and boys. The main MIH type prevalence was white/creamy demarcated opacities without PEB.

Prevalence of Peg-Shaped Lateral Incisors in Non-Syndromic Subjects: A Multi-Population Study

Abstract Objective: To evaluate the prevalence and gender-wise distribution of peg-shaped maxillary permanent lateral incisors among populations in Saudi Arabia representing different geographical locations (Saudi, Jordan, Egypt, Syria, Philippine, Pakistan, India and Bangladesh). Material and Methods: Panoramic radiographs of 9945 patients attending outpatient university dental clinics of College of Dentistry, Jouf University, Saudi Arabia between February 2014 and January 2018 were collected from the archives randomly. Two calibrated investigators examined the data, which were collected from the dental radiology department archives with prior permission from the authorities. The anomalies of maxillary lateral incisors (right and left) were investigated. Results: Among all geographic locations, the prevalence of peg laterals was more in males in comparison to females except in Pakistani and Philippine populations. Among the Saudi population, peg laterals' prevalence was more in case of right lateral incisor than the left incisor. Conclusion: A higher prevalence of peg laterals was found in Saudi. Conclusion: A higher prevalence of peg laterals was found in Saudi region, followed by Egypt. Among all geographic locations, the prevalence of peg laterals was higher in males than females except for Pakistan and Philippines populations. Among Saudi population prevalence of peg laterals was found to be higher in case of right lateral incisor when compared to the left.

Relationship between the inner intercanthal distance and the mesiodistal dimension of maxillary anterior teeth in a peruvian population with facial harmony / Relación entre la distancia intercantal interna y la dimensión mesiodistal de dientes anterosuperiores en una población peruana con armonía facial

Objective: To determine the relationship between the inner intercanthal distance and the mesiodistal dimension of the maxillary anterior teeth in a Peruvian population with facial harmony. Material and Methods: A cross-sectional study on a sample of 75 Peruvian subjects with facial harmony, with ages ranging between 18 and 30 years, was conducted. The inner intercanthal distance and the mesiodistal dimension of maxillary anterior teeth of each subject were measured with a digital vernier caliper. The relationship was evaluated by simple linear regression analysis. Results: A statistically significant direct relationship was found between the dimension of the inner intercanthal distance with the mesiodistal width of the lateral incisors (p=0.040, R2=5.65%), canines (p=0.032, R2=6.17%), and the total mesiodistal sum of the six anterior teeth (p=0.040, R2=5.63%), but not with the central incisors (p=0.273, R2=1.64%). Conclusion: The inner intercanthal distance showed a direct relationship with the total mesiodistal linear dimension of the maxillary anterior teeth, with the mesiodistal dimensions of the lateral incisors and canines in a Peruvian population with facial harmony.

Determinar la relación entre la distancia intercantal interna y la dimensión mesiodistal de los dientes anterosuperiores en individuos peruanos con armonía facial. Material y métodos: Se realizó un estudio transversal en una muestra de 75 individuos peruanos con armonía facial entre 18 a 30 años. Se midió la distancia intercantal interna y la dimensión mesiodistal de dientes anterosuperiores de cada sujeto con un calibrador vernier digital. La relación fue evaluada mediante análisis de regresión lineal simple. Resultados: Se encontró relación directa estadísticamente significativa entre la dimensión de la distancia intercantal interna con el ancho mesiodistal de los incisivos laterales (p=0.040, R2=5.65%), caninos (p=0.032, R2=6.17%) y la suma total mesiodistal de los seis dientes anteriores (p=0.040, R2=5.63%), más no con los incisivos centrales (p=0.273, R2=1.64%). Conclusión: La distancia intercantal interna mostró relación directa con la dimensión lineal mesiodistal total de los dientes anterosuperiores, con las dimensiones mesiodistales de los incisivos laterales y de caninos en individuos peruanos con armonía facial.

Morphological features of the incisive canal in patients of the first adult age

The incisive canal and its contents are often subject to intervention in maxillofacial surgery, otorhinolaryngology, and various areas of dentistry. The purpose of this paper is to study the variability of the dimensional and topographic characteristics of the incisive and nasal foramina of the incisive canal depending on the gender, shape, and parameters of the craniofacial complex in the first adult age. The authors have studied the parameters of the craniofacial complex, such as the morphological facial height, the upper morphological facial height, and the morphological facial breadth. They also have determined the Garson facial index and the upper face index. Cone-beam computerized tomography has been used in order to determine the number of foramina of Stensen and incisive foramina, their mesiodistal and vestibulo-lingual diameters, the shape of the incisive foramen; the distance from the incisive foramen to the labial inferior and palatal inferior points of the alveolar process; the distance from the incisive foramen to the central incisors, lateral incisors, canines of the maxilla; the bone density around the incisive canal; the length, shape, and type of incisive canal. Quantitative data were processed by variational statistical methods using the Statistica software package for Windows v 10.0. The significance of differences between groups was assessed using the Kolmogorov- Smirnov criterion at a significance level of p<0.05. It has been discovered that the incisive canal, the nasal and incisive foramina had a pronounced individual variability in size, shape, and topography depending on the gender, shape, the Garson facial index and upper face index, as well as the presence of correlations between the diameters and the number of nasal and incisive foramina. The authors have determined the values of bone tissue density in the area of the nasal and incisive foramina.

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.

Interdisciplinary planning as a landmark for treatment: Case report with a 2-years follow-up

Abstract Case report: young adult woman with esthetic complaints regarding her smile and frontal teeth aspect. At first glance, the problem seemed to be only the shape of the lateral upper incisors and a small diastema between the central incisors. The diagnosis shared between the orthodontist and the prosthetist led us to consider some other important aspects, such as the deep bite, the teeth inclination and the lips support. All these findings led us to consider that the right way to improve the esthetics of the patient's smile was to plan an orthodontic treatment. This would serve not only for the distribution of the spaces, but mostly it would improve all other problems, before the restoration of the upper lateral teeth with two ceramic veneers. Results: the treatment plan achieved the right distribution of spaces for upper lateral incisors, significant correction of the incisors inclination with important reduction of overbite and better lip support, upper laterals restorations with ceramic feldspathic veneers, obtaining a good integration with natural teeth satisfying patient complaint. Conclusion: in cases which involve interdisciplinary approach, the fundamental step comes from the beginning, when only an initial diagnosis shared among the team of specialists can define the patient problems from different points of view. In this way, we can better understand the competency fields and plan the right treatment and time sequence.

Resumo Relato de caso: paciente adulta jovem, sexo feminino, buscou tratamento devido à queixa com a estética do sorriso e o aspecto dos dentes anteriores. À primeira vista, o problema parecia ser apenas o formato dos incisivos laterais superiores e um pequeno diastema entre os incisivos centrais. O diagnóstico conjunto do ortodontista e do protesista fez com que considerássemos outros aspectos importantes, tais como mordida profunda, inclinação dentária e suporte labial. A partir de todas essas constatações, consideramos que a maneira mais adequada de melhorar a estética do sorriso seria planejar o tratamento ortodôntico. Assim, o tratamento serviria não apenas para melhor distribuição dos espaços, mas também melhoraria todos os outros problemas antes da restauração dos dentes laterais superiores ser realizada com duas facetas de cerâmica. Resultados: o tratamento planejado levou à correta distribuição dos espaços nos incisivos laterais superiores, com correção significativa da inclinação dos incisivos, importante redução da sobremordida e um melhor suporte labial, com restauração dos laterais superiores usando facetas de cerâmica feldspática, obtendo-se uma integração ideal com os dentes naturais, resolvendo as reclamações da paciente. Conclusão: em casos envolvendo abordagem multidisciplinar, as etapas iniciais são fundamentais, e apenas um diagnóstico inicial discutido entre a equipe de especialistas pode determinar os problemas do paciente sob diferentes perspectivas. Dessa forma, podemos compreender melhor os campos de competência e planejar a sequência e o tempo de tratamento mais adequados.

The maxillary incisor display at rest: analysis of the underlying components

ABSTRACT Introduction: Maxillary incisal display is one of the most important attributes of smile esthetics. Objective: The aim of this study was to determine the relationship between maxillary incisal display at rest (MIDR) and various soft tissue, hard tissue and dental components. Methods: A cross-sectional study was conducted on 150 subjects (75 males, 75 females) aged 18-30 years. The MIDR was recorded from the pretreatment orthodontic records. The following parameters were assessed on lateral cephalograms: ANB angle, mandibular plane angle, palatal plane angle, lower anterior and total anterior facial heights, upper incisor inclination, upper anterior dentoalveolar height, and upper lip length, thickness and protrusion. The relationship between MIDR and various skeletal, dental and soft tissue components was assessed using linear regression analyses. Results: The mean MIDR was significantly greater in females than males (p = 0.011). A significant positive correlation was found between MIDR and ANB angle, mandibular plane angle and lower anterior facial height. A significant negative correlation was found between MIDR and upper lip length and thickness. Linear regression analysis showed that upper lip length was the strongest predictor of MIDR, explaining 29.7% of variance in MIDR. A multiple linear regression model based on mandibular plane angle, lower anterior facial height, upper lip length and upper lip thickness explained about 63.4% of variance in MIDR. Conclusions: Incisal display at rest was generally greater in females than males. Multiple factors play a role in determining MIDR, nevertheless upper lip length was found to be the strongest predictor of variations in MIDR.

RESUMO Introdução: a exposição dos incisivos superiores é um dos fatores mais importantes na estética do sorriso. Objetivo: o objetivo desse estudo foi determinar a relação entre a exposição dos incisivos superiores em repouso (EISR) e diferentes componentes em tecidos moles, tecidos duros e dentários. Métodos: um estudo transversal foi conduzido com 150 pacientes (75 homens, 75 mulheres), com idades entre 18 e 30 anos. A EISR foi obtida nos registros pré-tratamento ortodôntico. Os seguintes parâmetros foram analisados nas radiografias laterais: ângulo ANB; ângulo do plano mandibular; ângulo do plano palatino; altura facial anterior inferior; altura facial anterior total; inclinação dos incisivos superiores; altura dentoalveolar anterior superior; comprimento, espessura e protrusão do lábio superior. A relação entre a EISR e os diferentes componentes esqueléticos, dentários e em tecidos moles foi analisada por meio de uma análise de regressão linear. Resultados: a EISR média foi significativamente maior nas mulheres do que nos homens (p= 0,011). Foi encontrada correlação positiva significativa entre a EISR e: o ângulo ANB, ângulo do plano mandibular e a altura facial anterior inferior. Uma correlação negativa significativa foi encontrada entre a EISR e o comprimento e a espessura do lábio superior. A análise de regressão linear mostrou que o comprimento do lábio superior foi o maior preditor da EISR, explicando 29,7% das variações na exposição dos incisivos superiores em repouso. Um modelo de regressão linear múltipla baseado no ângulo do plano mandibular, na altura facial anterior inferior, comprimento do lábio superior e espessura do lábio superior explicou cerca de 63,4% das variações na EISR. Conclusões: a exposição dos incisivos em repouso foi, de um modo geral, maior nas mulheres do que nos homens. Múltiplos fatores exercem influência na quantidade da exposição dos incisivos superiores em repouso; porém, o comprimento do lábio superior foi identificado como o maior preditor das variações na EISR.

Percepción de microdoncia y alteración vertical de tamaño de incisivos superiores por estudiantes de la Licenciatura de Cirujano Dentista de la Universidad Autónoma de Nayarit / Perception of microdontia and vertical alteration of size of upper incisors by students of the Dentist Surgery Degree of the Autonomous University of Nayarit

Objetivo: Evaluar la percepción de la microdoncia del incisivo lateral derecho y la disminución del tamaño vertical del incisivo central izquierdo por estudiantes de recién ingreso y último año de la Licenciatura de Cirujano Dentista de la Universidad Autónoma de Nayarit. Métodos: Se realizó un estudio descriptivo, observacional y transversal, valorando 10 fotografías de sonrisa, en una escala de 0 (nada atractivo) a 10 (atractivo). El grupo evaluador fue de 64 estudiantes, 32 de primer año y 32 de quinto año, calificaron 5 fotografías con reducción en el tamaño de la corona aumentando el nivel gingival del incisivo central y 5 con microdoncia del incisivo lateral. Resultados: Al evaluar la reducción en el tamaño de la corona aumentando el nivel gingival del incisivo central izquierdo, ambos grupos evaluaron con mayor calificación la fotografía control. En la microdoncia del incisivo lateral los estudiantes de quinto año evaluaron la imagen control en un promedio de 5,5 y el grupo de primer año evaluó mejor la fotografía control. Conclusiones: Ambos grupos detectaron los cambios presentados.

Objective: To evaluate the perception of microdontia of the right lateral incisor and the decrease in the vertical size of the left central incisor by first and last year students of the Dental Surgery Degree of the Autonomous University of Nayarit. Methods: A descriptive, observational and cross sectional study was conducted: 10 smile photographs were assessed on a scale from 0 (not attractive) to 10 (attractive). The evaluation group included 64 people: 32 first year students and 32 fifth year students. They rated five photographs with reduction in crown size and an increase in the gingival level of the central incisor, and five photographs with microdontia of the lateral incisor. Results: When evaluating the reduction in crown size and increase in the gingival level of the left central incisor, both groups rated the control photograph higher. In the microdontia of the lateral incisor, the fifth year students rated the control image 5.5 on average, and the first year group rated it higher. Conclusions: Both groups detected the changes.

Evaluation of the attractiveness of different gingival zeniths in smile esthetics

ABSTRACT Objective: To evaluate the smile attractiveness of different gingival zeniths by general dentists, orthodontists and laypersons and the esthetic perception in the symmetric and asymmetric changes in gingival zeniths. Methods: Posed photographs of five patients were taken and digitally manipulated in Keynote software, in the gingival zenith region, in increments of 0.5 to 1mm in maxillary central and lateral incisors, symmetrically and asymmetrically, in nine different ways for each patient. The photos were then uploaded to a website, where evaluators (general dentists, orthodontists and laypersons) could observe and vote according to their esthetic perception, scoring from 1 to 10, 1 being the least attractive and 10 the more attractive. Kruskal-Wallis and Mann-Whitney tests were used for comparison. Results: Asymmetric gingival zeniths were less attractive than symmetrical gingival zeniths; gingival zenith differences greater than 1mm were perceptible in the smile attractiveness, both by laypersons, general dentists and orthodontists. When comparing maxillary central incisors with maxillary lateral incisors, the aesthetic change performed in the central incisors are more perceptible than those performed in lateral incisors, both symmetrical and asymmetrical. In a general way, orthodontists and general dentists are more critical in the evaluation and perception of gingival zenith changes, with the laypersons perceiving this change only from 1mm of maxillary right central incisor asymmetrical change. Conclusions: Asymmetric gingival zeniths are less attractive than symmetrical ones. Gingival zenith differences greater than 1mm are perceptible in the smile attractiveness. Orthodontists and general dentists are more critical in evaluating smile esthetics.

RESUMO Objetivo: avaliar a atratividade e a percepção estética do sorriso com alterações simétricas e assimétricas dos zênites gengivais, por leigos, dentistas e ortodontistas. Métodos: foram tiradas fotografias posadas de cinco pacientes, de forma padronizada. Cada fotografia foi digitalmente manipulada no software Keynote, na região do zênite gengival, em incrementos de 0,5 a 1 mm, nos incisivos centrais e laterais superiores, de maneira simétrica e assimétrica, de nove formas diferentes para cada paciente. Posteriormente, essas fotografias foram dispostas em um website para que os avaliadores pudessem observá-las e, conforme sua percepção estética, dessem notas de 1 a 10, sendo 1 para pouco atrativa e 10 para muito atrativa. Foram utilizados os testes Kruskal-Wallis e Mann-Whitney para as comparações. Resultados: os zênites gengivais assimétricos foram considerados menos atrativos do que os simétricos. Diferenças entre os zênites gengivais maiores que 1 mm foram perceptíveis na atratividade do sorriso por todos os grupos de avaliadores. Quando comparados os incisivos centrais e laterais superiores, as alterações estéticas feitas nos incisivos centrais foram mais perceptíveis do que as feitas nos laterais, tanto as simétricas quanto as assimétricas. Os ortodontistas e os clínicos gerais foram mais críticos ao avaliar e perceber as alterações, com os leigos percebendo essa mudança somente a partir de 1 mm de alteração assimétrica no incisivo central superior direito. Conclusões: zênites gengivais assimétricos são menos atrativos do que os simétricos. Diferenças nos zênites maiores que 1 mm são perceptíveis na atratividade do sorriso. Ortodontistas e clínicos gerais são mais críticos ao avaliar sorrisos.

Root morphology and number of canals in mandibular central and lateral incisors using cone beam computed tomography

Abstract Most failures in endodontic treatment of mandibular incisors are due to the presence of a missed canal specifically the lingual. This investigation aimed to examine the root morphology and number of canals in mandibular incisors using cone beam computed tomography (CBCT). Two hundred and seven patients were assessed in terms of their mandibular central and lateral incisors of CBCT. The inclusion criteria were absence of root resorption, coronal restoration or root filling and clarity and optimal resolution of images. According to the Vertucci's classification, number of roots and canals and type of canal were evaluated by two oral and maxillofacial radiologists. In order to data analysis SPSS version 16 and descriptive statistics were implemented. All mandibular incisors had one root. Most central (84.5%) and lateral (78.2%) incisors had a single canal (p= 0.065). The majority of central (54.5%) and lateral (56.5%) incisors were Vertucci's type I (p= 0.102). Prevalence of one canal in males: central (84.8%), lateral (77.9%) and in females: central (84.2%), lateral (78.5%) (p= 0.518). Prevalence of Vertucci's type I in males: central (52.3%), lateral (45.3%) and in females: central (56.1%), lateral (64.4%) (p=0.188). The prevalence of two canals was 15.5% (central) and 21.8% (lateral) in mandibular incisors. The Vertucci's type I was the most typical kinds of mandibular incisors. Considering the limitations of periapical radiography in determining canal morphology, CBCT can be helpful in case of any concern regarding root canal morphology.

Resumo A maioria das falhas no tratamento endodôntico dos incisivos mandibulares é devida à presença de um canal perdido, especificamente do lingual. Esta investigação teve como objetivo analisar a morfologia radicular e o número de canais nos incisivos inferiores utilizando a tomografia computadorizada de feixe cônico (TCFC). Duzentos e sete pacientes foram avaliados em termos de seus incisivos centrais e laterais mandibulares de TCFC. Os critérios de inclusão foram ausência de reabsorção radicular, restauração coronária ou preenchimento radicular e clareza e resolução ótima das imagens. De acordo com a classificação de Vertucci, o número de raízes e canais e o tipo de canal foram avaliados por dois radiologistas orais e maxilo-faciais. Para análise dos dados, o SPSS versão 16 e análise estatística descritiva foram implementados. Todos os incisivos inferiores tinham uma raiz. A maioria dos incisivos centrais (84,5%) e laterais (78,2%) apresentava um único canal (valor de P: 0,065). A maioria dos incisivos centrais (54,5%) e laterais (56,5%) eram do tipo I de Vertucci (valor de P: 0,102). Prevalência de um canal no sexo masculino: central (84,8%), lateral (77,9%) e no feminino: central (84,2%), lateral (78,5%) (valor de P: 0,518). Prevalência de Vertucci tipo I em homens: central (52,3%), lateral (45,3%) e feminina: central (56,1%), lateral (64,4%) (valor de P: 0,188). A prevalência de dois canais foi de 15,5% (central) e 21,8% (lateral) nos incisivos inferiores. O tipo I de Vertucci era dos tipos mais comuns de incisivos inferiores. Considerando as limitações da radiografia periapical na determinação da morfologia do canal, a TCFC pode ser útil em caso de qualquer preocupação com relação à morfologia do canal radicular.

Mandibular anterior crowding: normal or pathological?

ABSTRACT The teeth become very close to each other when they are crowded, but their structures remain individualized and, in this situation, the role of the epithelial rests of Malassez is fundamental to release the EGF. The concept of tensegrity is fundamental to understand the responses of tissues submitted to forces in body movements, including teeth and their stability in this process. The factors of tooth position stability in the arch - or dental tensegrity - should be considered when one plans and perform an orthodontic treatment. The direct causes of the mandibular anterior crowding are decisive to decide about the correct retainer indication: Should they be applied and indicated throughout life? Should they really be permanently used for lifetime? These aspects of the mandibular anterior crowding and their implication at the orthodontic practice will be discussed here to induct reflections and insights for new researches, as well as advances in knowledge and technology on this subject.

RESUMO Os dentes ficam muito próximos quando estão apinhados, mas suas estruturas permanecem individualizadas e, nessa situação, o papel dos restos epiteliais de Malassez é fundamental para liberar o EGF. A tensigridade é um conceito chave para compreender as respostas dos tecidos submetidos às forças nos movimentos corporais, incluindo os dentes e sua estabilidade nesse processo. Os fatores da estabilidade de posição de um dente na arcada dentária — ou tensigridade dentária — devem ser considerados quando se planeja e finaliza um caso na prática clínica ortodôntica. As causas diretas do apinhamento dentário anteroinferior são determinantes para se refletir se a contenção deve ser mesmo indicada e aplicada por toda a vida e se, necessariamente, deve ser usada de forma permanente. Esses aspectos do apinhamento dentário anteroinferior e suas implicações na prática clínica serão aqui abordados para induzir reflexões e insights de novas pesquisas, bem como avanços no conhecimento e tecnologia sobre esse assunto.

Modificações na forma e na textura para efeitos ópticos em dentes anteriores / Shape and texture modifications for optical effects in anterior teeth

Para se estabelecer corretamente os efeitos de forma, luz, reflexão, absorção, entre outros, nos dentes incisivos, é necessário compreendermos as características anatômicas gerais das coroas de dentes anteriores, suas linhas ópticas e como cada uma delas comanda o brilho e a reflexão. De acordo com as inclinações e ângulos formados entre as faces (vestibular, Mesial, Distal e Incisal) conseguimos trabalhar em cera ou em cerâmica as áreas ópticas com seus efeitos desejados. Este artigo aborda alguns conceitos e dicas práticas para a aquisição de áreas de sombra e luz e um resultado estético e harmonioso nos dentes anteriores.

In order to correctly establish the effects of shape, light, reflection, absorption, among others in the incisor teeth, it is necessary to understand the general anatomical characteristics of anterior tooth crowns, their optical lines and how each one rules brightness and reflection. According to the slopes and angles formed between the faces (Vestibular, Mesial, Distal and Incisal), we can work the optical areas with their desired effects with wax or ceramic. This article discusses some concepts and practical tips for acquiring shadow and light areas and an aesthetic and harmonious result in the anterior teeth.