Factores etiopatogénicos de maloclusión: el factor dentario en la organización de la oclusión. Parte III / Etiopathogenic factors of malocclusion: the dental effect in occlusal organization. Part III

Esta publicación es la última de una serie de tres, dirigida a la organización de la oclusión, en el marco de un enfoque sistémico. En las anteriores fueron desarrollados los temas referidos al espacio en los arcos dentarios restando analizar, entonces, aspectos de la erupción dentaria. Al respecto, se sintetizarán conceptos de la evolución deseable desde el origen de los folículos dentarios hasta su inclusión en el arco y contacto con el antagonista y se presentarán ejemplos de alteraciones ordenadas según el avance biológico de la dentición (AU)

This publication is the last in a series of three, aimed at the organization of occlusion, within the framework of a systemic approach. In the previous ones, the topics related to the space in the dental arches were developed, leaving to analyze, then, aspects of the dental eruption. In this regard, concepts of the desirable evolution from the origin of the dental follicles to their inclusion in the arch and contact with the antagonist will be synthesized, and examples of alterations ordered according to the biological progress of the dentition will be presented (AU)

Características Morfológicas y Morfométricas de la Silla Turca Según Clase Esqueletal / Morphological and Morphometric Characteristics of the Sella Turcica According to Skeletal Class

El desarrollo craneofacial es un proceso complejo con diversos factores involucrados. Cuando las maloclusiones son de origen esqueletal pueden generar una relación ortognática (clase I), retrognática (clase II) o prognática (clase III) de la mandíbula respecto de la maxila. Esta configuración está estrechamente relacionada con la base del cráneo donde la silla turca ha sido estudiada con este fin debido a su origen ectomesenquimático (Dasgupta et al., 2018) y sus relaciones anatómicas. Diversos estudios se han realizado para dilucidar esta relación y este trabajo busca aportar a la discusión comparando las características de la silla turca entre las maloclusiones esqueletales a través de telerradiografías laterales. El estudio se realizó mediante 52 placas radiográficas de individuos de entre 18 a 24 años con igual número de sujetos masculinos y femeninos, 15 de clase I, 7 de clase II y 30 de clase III. Se realizó la medición digital del área radiográfica de la silla turca y se clasificó morfológicamente mediante las categorías de Axelsson et al. (2004). Se utilizó coeficiente de correlación intraclase con un 95 % de confianza arrojando un valor de 0,88 para el área de la silla turca, 0,89 para el ángulo ANB y de 0,70 para el valor Wits demostrando una excelente fiabilidad del observador. Con un 95 % de confianza la prueba exacta de Fisher evidenció una asociación significativa (p = 0,029) entre las variaciones morfológicas de la ST y la clase esqueletal siendo más frecuentes en clase III. La prueba H de Kruskal Wallis no arrojó diferencias significativas (p=0,550) en las medianas del área selar entre las clases esqueletales. Las variaciones morfológicas parecen ser más relevantes que las variaciones anatómicas en esta asociación. Se requieren nuevos estudios en población chilena con un mayor número de casos.

SUMMARY: Craniofacial development is a complex process with several factors involved. When malocclusions have a skeletal origin, they can generate an orthognathic (class I), retrognathic (class II) or prognathic (class III) relationship of the mandibular bone respect to the maxilla. This configuration is closely related to the base of the skull where the sella turcica has been studied for this purpose due to its ectomesenchymal origin (Dasgupta et al., 2018) and its anatomical relationships. Several studies have been conducted to elucidate this relationship and this work seeks to contribute to the discussion by comparing the characteristics of the sella turcica among skeletal malocclusions through lateral teleradiographies. The study was conducted using 52 radiographic plates of individuals between 18 and 24 years old with an equal number of male and female subjects, 15 class I, 7 class II and 30 class III. The radiographic area of the sella turcica was digitally measured and morphologically classified using the categories of Axelsson et al. (2004). An intraclass correlation coefficient was obtained with 95 % confidence, yielding a value of 0.88 for the sella turcica area, 0.89 for the ANB angle and 0.70 for the Wits value, demonstrating excellent observer reliability. With 95 % confidence, Fisher's exact test showed a significant association (p = 0.029) between the morphological variations of the ST and the skeletal class, being more frequent in class III. The Kruskal Wallis H test did not show significant differences (p=0.550) in median sellar area between skeletal classes. Morphological variations seem to be more relevant than anatomical variations in this association. New studies are required in the Chilean population with a greater number of cases.

Abordaje miofuncional / Myofunctional approach

La Ortodoncia Miofuncional basa sus objetivos de diagnóstico y tratamiento en el abordaje integral del paciente, tomando el cuerpo en su conjunto y la boca como expresión de desequilibrios funcionales. Los huesos responden a la acción muscular; si no se recupera la función, se compromete la estabilidad de la forma. El objetivo de este artículo es describir el potencial de los dispositivos preformados, que se trabajan en tres fases. • Fase 1: un dispositivo de silicona blanda para relajar los músculos y recuperar la respiración nasal. • Fase 2: un dispositivo de silicona reforzada para estimular el desarrollo transversal de los arcos. Se entrena la correcta posición de la lengua y el cierre labial. Se indican ejercicios de deglución y una alimentación saludable como parte de la terapia. • Fase 3: se instala otro dispositivo de silicona rígida para lograr estabilidad de las estructuras, ganando el paladar libre. Todos los dispositivos cuentan con una guía para la correcta ubicación de la lengua. Restaurar los patrones funcionales saludables es un requisito imprescindible en todo tratamiento de Ortodoncia. Tanto más favorable será si iniciamos el tratamiento en las fases más tempranas en que se diagnostican los Desórdenes Miofuncionales Orofaciales (DMO). Desórdenes Miofuncionales de los músculos y funciones de la cara y la boca Los DMO pueden afectar, directa o indirectamente, la lactancia materna, el crecimiento y desarrollo del esqueleto facial, la masticación, la deglución, el habla, la oclusión, la cinemática de la articulación temporomandibular, la higiene bucal, la estabilidad del tratamiento de Ortodoncia, la estética facial, etcétera. Con la terapia miofuncional, un paciente puede recuperar la alegría de comer, hablar, respirar e incluso dormir más profundamente, y además las mejoras cosméticas pueden ayudar a recuperar la confianza y la autoestima de los pacientes.

OMT (Orofacial myofunctional therapy), is definitely an interesting tool in nowadays, offering a higher range of treatment for both adults and children's… The Myofunctional orthodontics bases its diagnosis and treatment goals, by approaching the patient comprehensively from the macro to the micro, taking the body as a whole and the mouth as an expression of functional imbalances. The bones are slaves to the muscles, if the function not be recovered, it will compromises the stability of form. The aim of this article is to share the potential of preformed devices worked in three Phases •Phase 1: A device of soft silicone to relax the muscles and recover nasal breathing; •Phase Phase 2: reinforced silicone to stimulate the transversal development of the arches along with lip-tongue postures and swallowing exercises, even taking a healthy eating as part of the therapy. •Phase In a Phase 3: Another device of rigid silicone to achieve stability of the structures, gaining the free palate stands out, and all devices have a guide for the correct location of the tongue. Restoring healthy functional patterns is an essential requirement in all orthodontic treatments, even more if we help them from earlier stages of their OMDs (Orofacial Myofunctional Disorders), of the muscles and functions of the face and mouth. OMDs may affect, directly and/or indirectly, breastfeeding, facial skeletal growth and development, chewing, swallowing, speech, occlusion, temporomandibular joint movement, oral hygiene, stability of orthodontic treatment, facial esthetics, and more. We are completely aware that with myofunctional therapy, a patient can regain the joy of eating, speaking, breathing, and even sleeping more soundly, and also cosmetics improvements can help restore confidence and self's teams of our patients

Relación entre mordida cruzada y sistema de control postural / Relationship between crossbite and postural control system

En la literatura es posible encontrar numerosos estudios que han demostrado una estrecha relación anatómica, funcional, neurológica y fisiológica entre la oclusión, la mandíbula y las regiones del cuello.1,2,3,4 Se ha observado una coactivación entre los músculos mandibulares y el complejo cuello-hombros durante los movimientos mandibulares y al masticar. Un enfoque corporal más integral ha permitido demostrar que existen conexiones neuronales entre los sistemas sensoriales-motores de las aferencias trigeminales que provienen de las estructuras orales (oclusión, músculos, articulación temporomandibular, posición de la mandíbula) de la cara y de los músculos oculomotores, con el cuello,5,6 el sistema vestibular y el apoyo plantar, teniendo injerencia en la alineación corporal, estabilidad y control postural del cuerpo.7,8,9,10 A su vez, el sistema vestibular contribuye a la regulación de la actividad de los músculos maseteros.11,12,13,14,15 Cualquier alteración en el sistema de control postural puede influir sobre el sistema estomatognático.16,17 Desde este enfoque global neurofisiológico se analizará en este artículo la relación entre la mordida cruzada unilateral posterior y la laterodesviación mandibular con el sistema de control postural. La comprensión de la relación entre las disfunciones orales con las asimetrías y la función del control postural permite a la Odontología tener una mirada global del ser humano, poder establecer abordajes terapéuticos integrales y trabajar en interdisciplina con otros profesionales de la salud, alcanzando una mayor estabilidad, ergonomía postural y mayor eficiencia de gasto energético.18,19

In the literature it is possible to find numerous studies that have demonstrated a close anatomical, functional, neurological and physiological relationship between occlusion, jaw and neck regions.1,2,3,4 Coactivation between the mandibular muscles and the neck-shoulder complex has been observed during mandibular movements and chewing. A more global body approach has allowed to demonstrate that there are neural connections between the sensory-motor systems of the trigeminal afference that come from the oral structures (occlusion, muscles, temporomandibular joint, jaw position), the face,the oculomotor muscles, the neck,5,6 the vestibular system, and plantar support, having an influence on body alignment, stability and postural control of the body.7,8,9,10 In turn, the vestibular system contributes to the regulation of the activity of the masseter muscles.11,12,13,14,15 Any alteration in the postural control system can influence the Stomatognathic System.16,17 From this global neurophysiological approach, the relationship between posterior unilateral crossbite and mandibular lateral deviation will be analyzed in this article in connection with the postural control System. Understanding the relationship between oral dysfunctions with asymmetries and the function of postural control allows Dentistry to have a global view of the human being, being able to establish integral therapeutic approaches ininterdisciplinary work with other health professionals, achieving better stability, postural ergonomics and greater energy expenditure efficiency.

Necesidad del tratamiento ortodóntico según el índice estético dental en la etnia Kichwa Saraguro, Ecuador / Need for Orthodontic Treatment according to the Dental Esthetic Index in the Kichwa Saraguro Ethnic Group, Ecuador

Introducción: Los rasgos oclusales en un grupo étnico pueden estar asociados con factores genéticos y socioculturales que contribuyen a la morfología de los rasgos oclusales y faciales en grupos indígenas. Objetivo: Determinar la necesidad de tratamiento ortodóntico según el índice estético dental y el sexo en la etnia Kichwa Saraguro, Ecuador. Métodos : Estudio observacional, descriptivo, transversal, realizado en el año 2018 en 465 adolescentes de 12 a 16 años, pertenecientes a la etnia Kichwa Saraguro y residentes en Loja, Ecuador. Se empleó la estadística descriptiva, se obtuvo la frecuencia absoluta y el porcentaje para las variables cualitativas; la media, la desviación estándar y la mediana para variables cuantitativas. Para la determinación de normalidad de los datos se usó la prueba Kolmogorov Smirnov y para la relación del sexo con los componentes del índice estético dental y la necesidad de tratamiento ortodóntico se usó la prueba de U de Mann-Whitney y ji al cuadrado. Un valor de α = 0,05 se consideró como estadísticamente significativo. Resultados: Del total de la población, en el 61,06 por ciento se encontró una maloclusión leve con tratamiento innecesario; en el 18,06 por ciento maloclusión manifiesta con tratamiento optativo, en el 9,89 por ciento maloclusión grave con tratamiento deseable y en el 10,97 por ciento maloclusión muy grave con tratamiento obligatorio. Se encontraron diferencias significativas de p = 0,028 en dientes incisivos, caninos y premolares visibles perdidos del maxilar y la mandíbula. Conclusión: Más de la mitad de los participantes de la etnia Kichwa Saraguro presentaron maloclusión leve con tratamiento innecesario y, de acuerdo con el sexo, más de un cuarto de los participantes femeninos mostraron maloclusión manifiesta con tratamiento optativo y maloclusión grave con tratamiento sumamente deseable(AU)

Introduction: Occlusal features in an ethnic group may be associated with genetic and sociocultural factors that contribute to the morphology of occlusal and facial features in indigenous groups. Objective: To determine the need for orthodontic treatment according to the dental esthetic index and sex in the Kichwa Saraguro ethnic group, Ecuador. Methods: Observational, descriptive, cross-sectional study that was carried out in 2018 in 465 adolescents aged 12 to 16 years, belonging to the Kichwa Saraguro ethnic group and residing in Loja, Ecuador. Descriptive statistics were used. Absolute frequency and percentage were obtained for qualitative variables, and mean, standard deviation and median for quantitative variables. The Kolmogorov Smirnov test was used to determine the normality of the data, and the Mann-Whitney U test and chi-squared test were used to determine the relationship between sex and the components of the dental esthetic index and the need for orthodontic treatment. A value of α = 0.05 was considered statistically significant. Results: Of the total population, 61.06 percent were found to have a mild malocclusion with unnecessary treatment. In 18.06 percent manifest malocclusion with optional treatment was found. Severe malocclusion with desirable treatment was found in 9.89 percent and very severe malocclusion with mandatory treatment in 10.97 percent. Significant differences of p = 0.028 were found in visible missing incisors, canines and premolars of the maxilla and mandible. Conclusion: More than half of the participants from the Kichwa Saraguro ethnic group presented mild malocclusion with unnecessary treatment and, according to sex, more than a quarter of the female participants showed manifest malocclusion with optional treatment and severe malocclusion with highly desirable treatment(AU)

Impact of oral onditions on Quality of Life in Peruvian Preschoolers in Rural and Urban Areas / Impacto de las alteraciones bucales en la calidad de vida de preescolares peruanos de zonas rurales y urbanas

Abstract The objective of this study is to determine the impact of oral conditions on the quality of life related to the oral health of preschool children in a rural and urban area of Cusco. The study was descriptive and cross-sectional, from a population of 179 preschoolers aged 3 to 5 years, from two public early childhood education institutions, and their respective parents or caregivers in the department of Cusco, Peru. We worked with the entire population that met the inclusion and exclusion criteria, seventy-four preschool children were selected for each area, deciding to have the same amount of children per group based on the smallest group. A clinical odonto-stomatological examination was carried out for oral conditions (dental caries, malocclusion, and dental trauma) according to the WHO's criteria and a survey that was used for sociodemographic characteristics. In addition, a validated Peruvian version of the ECOHIS questionnaire was used to obtain data on the impact on quality of life. All the variables of the total and individual scores of the ECOHIS domains were analyzed individually and the Kruskal-Wallis test was used to determine the association between variables. The oral conditions prevalence in preschool children in rural areas referring to dental caries was 100% (dmft index > 6), dental trauma 10.8%, and malocclusions 60.8%; for the urban area dental caries was 93.2% (dmft index > 6), dental trauma 9.5% and malocclusions 36.5%. Of the three oral conditions only the experience of dental caries was related to the OHRQOL of preschoolers in urban and rural areas.

Resumen El objetivo de este estudio es determinar el impacto de las alteraciones bucales en la calidad de vida relacionada con la salud bucal de niños preescolares de una zona rural y urbana de Cusco. El estudio fue descriptivo y transversal, de una población de 179 preescolares de 3 a 5 años de edad, de dos instituciones públicas de educación inicial, y sus respectivos padres o cuidadores en el departamento de Cusco, Perú. Se trabajó con toda la población que cumplió con los criterios de inclusión y exclusión, se seleccionaron setenta y cuatro niños preescolares por cada área, decidiendo tener la misma cantidad de niños por grupo en base al grupo más pequeño. Se realizó un examen clínico odonto-estomatológico para detectar alteraciones bucales (caries dental, maloclusión y trauma dental) según los criterios de la OMS y una encuesta que se utilizó para las características sociodemográficas. Además, se utilizó una versión peruana validada del cuestionario ECOHIS para obtener datos sobre el impacto en la calidad de vida. Todas las variables de los puntajes totales e individuales de los dominios ECOHIS fueron analizadas individualmente y se utilizó la prueba de Kruskal-Wallis para determinar la asociación entre variables. La prevalencia de alteraciones bucales en niños preescolares de zonas rurales referida a caries dental fue del 100% (índice dmft > 6), traumatismo dental 10,8% y maloclusiones 60,8%; para la zona urbana la caries dental fue del 93,2% (índice dmft > 6), el traumatismo dental 9,5% y las maloclusiones 36,5%. De las tres alteraciones bucales, sólo la experiencia de caries dental se relacionó con la OHRQOL de los preescolares de las zonas urbana y rural.

Prevalencia de Anomalías Dentomaxilares y Necesidad de Tratamiento Ortodóncico en Escolares del Pueblo Originario Rapa Nui / Prevalence of Dentomaxillary Anomalies and Need for Orthodontic Treatment in School Children of the Rapa Nui Native People

El objetivo de este estudio fue determinar la prevalencia de anomalías dentomaxilares y la necesidad de tratamiento ortodóncico en escolares pertenecientes al pueblo originario de Rapa Nui. Se realizó un estudio descriptivo, observacional, transversal y no probabilístico. Se evaluaron 85 alumnos entre primero básico y primero medio, entre los 6 y 16 años de edad, de dos colegios de Rapa Nui. Se realizó un examen clínico estandarizado, realizado por dos investigadores previamente calibrados, donde se completó una ficha clínica diseñada para el estudio. Para el análisis de las anomalías dentomaxilares se realizó un escaneo digital de la cavidad oral completa para su posterior análisis. De 85 estudiantes evaluados, 75 (88,2 %) se encontraban afectados por algún tipo de anomalía dentomaxilar en el plano sagital, vertical y/o transversal, independiente de su gravedad. Un 87,1 % de los estudiantes necesitan tratamiento ortodóncico según el Índice de Necesidad de Tratamiento Ortodóncico, de los cuales un 57,7, % se clasificó dentro de los rangos de moderado, grave y muy grave. Existe una alta prevalencia de anomalías dentomaxilares en los escolares pertenecientes al pueblo originario Rapa Nui, encontrándose por sobre las cifras nacionales como internacionales, lo cual da como resultado que la mayoría de los alumnos evaluados necesiten de algún tipo tratamiento ortodóncico, ya sea preventivo, interceptivo y/o correctivo.

The aim of this study was to determine the prevalence of dentomaxillary anomalies and the need for orthodontic treatment in schoolchildren belonging to the Rapa Nui native people. A descriptive, observational, cross- sectional and non-probabilistic study was carried out. Eighty- five students between first grade and first middle school, between 6 and 16 years of age, from two schools of Rapa Nui were evaluated. A standardized clinical examination was performed by two previously calibrated investigators, where a clinical record designed for the study was completed. For the analysis of dentomaxillary anomalies, a digital scan of the full mouth was performed for subsequent analysis. Of 85 students evaluated, 75 (88.2 %) were affected by some type of dentomaxillary anomaly in the sagittal, vertical and/or transversal plane, regardless of its severity. Some 87.1 % of the students needed orthodontic treatment according to the Orthodontic Treatment Need Index, of which 57.7 % were classified within the moderate, severe and very severe ranges. There is a high prevalence of dentomaxillary anomalies in schoolchildren belonging to the Rapa Nui native people, which is above the national and international figures, resulting in the majority of the students evaluated needing some type of orthodontic treatment, whether preventive, interceptive and/or corrective.

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.

Resolución de maloclusión con severo escalón anterior empleando fuerzas diferenciales / Resolution of a malocclusion with a severe anterior step employing differential forces

Paciente de 21 años de sexo masculino con una distoclusión esqueletal y alveolo dentaria severa, hábito de succión del dedo que contribuye a agravar el escalón de 15 mm. Demanda tratamiento para mejorar su oclusión y estética. Si bien lo indicado es un tratamiento ortodóncico con cirugía ortogná- tica para modificar su perfil muy convexo con una distancia mentocervical acortada, no es aceptado por el paciente, planificándose entonces camuflaje ortodóncico con exodoncias de PD 14 y 24 y reduc- ción del escalón mediante anclaje diferencial que emplea fuerzas de volcamiento para no perderlo dado el gran overjet a reducir. Habiendo varias piezas dentarias con anomalías de color, defectos en el esmalte, una corona metálica en PD 36 y limitacio- nes presupuestarias se realizó la estética final con reconstrucciones de resina (AU)

A 21-year-old male patient with a severe skeletal and alveolar distoclusion, finger sucking habit that contributes to aggravate the 15 mm step. He demands treatment to improve its occlusion and aesthetics. Although orthodontic treatment with orthognathic surgery is indicated to modify its highly convex profile with a shortened mentocervical distance, it is not accepted by the patient, so orthodontic camouflage is planned with extractions of 14 and 24 and reduction of the step by means of differential anchorage that uses overturning forces so as not to lose anchorage due to the great overjet. Having several dental pieces with color anomalies, enamel defects, a metallic crown in 36 and budgetary limitations, the final aesthetics was performed with resin reconstructions (AU)

Factores etiopatogénicos de maloclusión. Parte II: el factor dentario en la organización de la oclusión / Etiopathogenic factors of malocclusion. Part II: the dental effect in occlusal organization

El objetivo de esta publicación es continuar con el tema desarrollado en la primera parte, donde se esbozaron aspectos generales de la organización de la oclusión, como introducción al estudio de la etiopa- togenia de las maloclusiones, con el factor dentario como aspecto central. Probablemente es el que com- parte mayor presencia en maloclusiones, donde el factor principal es de otro origen, es decir, esqueletal o neuromuscular. Se expondrá, a continuación, la condición del espacio en los arcos dentarios, sea por exceso o defecto de material dentario, sea por pérdida de perímetro del arco dentario, en cuanto al diagnóstico y a conductas preventivas. La parte III se centrará en alteraciones de erupción dentaria (AU)

The objective of this publication is to continue with the theme developed in the first part, where general aspects of the organization of the occlusion were outlined, as an introduction to the study of the etiopathogenesis of malocclusions, with the dental factor as a central aspect. It is probably the one that shares the greatest presence in malocclusions where the main factor is of another origin, that is, skeletal or neuromuscular. Next, the condition of the space in the dental arches will be exposed, whether due to excess or defect of dental material or loss of perimeter of the dental arch, in terms of diagnosis and preventive behaviors. Part III will focus on dental eruption disorders (AU)

Prevalence of tooth loss, bleeding on probing and malocclusion as oral disease indicators in Costa Rican male adolescents: a cross sectional study / Prevalencia de la pérdida de piezas dentales, del sangrado al sondeo y la maloclusión como indicadores de enfermedades orales en adolescentes varones costarricenses: un estudio transversal

The evidence to characterize oral health during adolescence in Costa Rica is limited. This lack of adequate research makes it difficult to develop appropriate health policies for this subgroup of the population. This is particularly important because adolescence is the period during which good health habits must take root in order to foster good physical and cognitive development. This study aims to determine the prevalence of tooth loss, bleeding on probing and malocclusion in Costa Rican male adolescents at the ''Colegio Técnico Profesional San Agustín'' (St. Augustine's Technical High School) located in the province of Cartago. Data was collected from 428 male adolescents aged 12-22 years in a cross-sectional study during 2019. Prevalence of tooth loss was calculated as the number of individuals having lost at least one tooth. The average number of teeth lost by individuals was also recorded. The bleeding on probing was an indicator used as a proxy parameter for monitoring periodontal health where the presence of bleeding on probing and calculus was also recorded. Malocclusion was measured using the Dental Aesthetic Index (DAI). The results showed that the prevalence of tooth loss, bleeding on probing and malocclusion was of 19%, 70.0% and 98%, respectively. It was also found that 81% of the participants had all their teeth, 11% had lost 1 tooth, 8% had lost more than one tooth of which 0.5% had lost more than 5 teeth. Considering a general classification of periodontal problems based on bleeding on probing and presence of calculus, the prevalence of periodontal problems increases to 92%. Regarding the DAI, the category identifying a very severe malocclusion was the most prevalent in the sample (88%). It is alarming the high prevalence of tooth loss, bleeding on probing, and malocclusions in a sample of Costa Rican male adolescents, compared to similar studies in other countries. The overarching conclusion of this study is that oral diseases represent an important health problem that urgently need proper public health action.

La evidencia para caracterizar la salud bucal durante la adolescencia en Costa Rica es limitada. Esta falta de investigación adecuada dificulta el desarrollo de políticas de salud convenientes para este subgrupo de la población. Esto es particularmente importante porque la adolescencia es el período durante el cual se deben arraigar buenos hábitos de salud para fomentar un buen desarrollo físico y cognitivo. Este estudio tiene como objetivo determinar la prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusión en adolescentes varones costarricenses del Colegio Técnico Profesional San Agustín ubicado en la provincia de Cartago. Se recopilaron datos de 428 adolescentes varones de 12 a 22 años en un estudio transversal durante 2019. La prevalencia de pérdida de piezas dentales se calculó como el número de individuos que habían perdido al menos una pieza dental. También se registró el número promedio de dientes perdidos por individuos. El sangrado al sondeo fue un indicador utilizado como parámetro para el seguimiento de la salud periodontal donde también se registró la presencia de sangrado al sondeo y cálculo dental. La maloclusión se midió utilizando el Índice Estético Dental (DAI, por sus siglas en inglés). Los resultados mostraron que la prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusión fue del 19%, 70,0% y 98%, respectivamente. También se encontró que el 81% de los participantes tenían todos sus dientes, el 11% había perdido 1 pieza dental, el 8% había perdido más de una pieza dental, de los cuales el 0,5% había perdido más de 5 piezas dentales. Considerando una clasificación general de problemas periodontales basada en sangrado al sondeo y presencia de cálculo, la prevalencia de problemas periodontales aumenta al 92%. En cuanto al DAI, la categoría que identifica una maloclusión muy severa fue la más prevalente en la muestra (88%). Es alarmante la alta prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusiones en una muestra de adolescentes varones costarricenses, en comparación con estudios similares en otros países. La conclusión general de este estudio es que las enfermedades bucodentales representan un importante problema de salud que necesita urgentemente una acción adecuada de salud pública.

Relação entre desmame precoce, desenvolvimento de hábitos bucais deletérios e maloclusões na infância / Relationship between early weaning, development of harmful oral habits and malocclusions in childhood

Objetivo: o objetivo desta pesquisa foi analisar a associação do tempo de aleitamento materno com a prática de hábitos deletérios e o desenvolvimento de maloclusões na primeira infância. Materiais e Métodos: foram aplicados 171 formulários às mães com 18 anos ou mais que acompanharam o processo de amamentação de seu(s) filho(s) de 4 a 10 anos de idade. O questionário foi composto por 22 perguntas, sendo 15 específicas e relacionadas ao aleitamento, hábitos deletérios da criança (uso de chupeta, sucção de dedo e sucção do próprio lábio) e maloclusões específicas (mordida cruzada posterior, mordida cruzada anterior e mordida aberta). Resultados: a prevalência da amamentação exclusiva por 6 meses ou mais foi de 52%, enquanto 29,8% das crianças foram amamentadas de 0 a 5 meses e 18,2% nunca foram amamentadas no seio exclusivamente. Quanto a alimentação complementar, grande parcela (37,4%) encontrada evidenciou início após os 6 meses; 57,9% das mães relataram algum tipo de dificuldade para amamentar e 34,5% das crianças fizeram uso de chupeta. Em relação aos hábitos deletérios, 10% desenvolveram sucção de dedo. O relato de desenvolvimento de maloclusões foi de 9,4% das crianças com mordida cruzada posterior; 7,6% mordida cruzada anterior e 18,7% mordida aberta anterior. Conclusão: sendo assim, é possível inferir que o tempo preconizado pela Organização Mundial da Saúde para aleitamento materno exclusivo foi fundamental para o não desenvolvimento de hábitos deletérios e maloclusões. Em contrapartida, quanto mais cedo a introdução de alimentos complementares, e a interrupção do aleitamento exclusivo nos seis primeiros meses, maior o risco do desenvolvimento de hábitos e consequentemente maloclusões.

Objective: the objective of this research was to analyze the association of breastfeeding duration with the practice of deleterious habits and the development of malocclusions in early childhood. Materials and Methods: a total of 171 forms were applied to mothers aged 18 years or older who followed the breastfeeding process of their child(ren) between 4 and 10 years of age. The questionnaire consisted of 22 questions, 15 of which were specific and related to breastfeeding, the child's deleterious habits (use of a pacifier, finger sucking and lip sucking) and specific malocclusions (posterior crossbite, anterior crossbite and open bite). Results: the prevalence of exclusive breastfeeding for 6 months or more was 52%, while 29.8% of children were breastfed from 0 to 5 months and 18.2% were never exclusively breastfed. As for complementary feeding, a large portion (37.4%) found to start after 6 months; 57.9% of the mothers reported some type of difficulty in breastfeeding and 34.5% of the children used a pacifier. Regarding deleterious habits, 10% developed finger sucking. The report of development of malocclusions was 9.4% of children with posterior crossbite; 7.6% anterior crossbite and 18.7% anterior open bite. Conclusion: therefore, it is possible to infer that the time recommended by the World Health Organization for exclusive breastfeeding was fundamental for the non-development of deleterious habits and malocclusions. On the other hand, the earlier the introduction of complementary foods and the interruption of exclusive breastfeeding in the first six months, the greater the risk of developing habits and, consequently, malocclusions.

Análise comparativa entre a influência da amamentação e hábitos bucais deletérios no crescimento craniofacial / Comparative analysis between the influence of breastfeeding and deleterial oral habits on craniofacial growth

A adoção da chupeta e mamadeira pelos pais podem trazer problemas no desenvolvimento craniofacial da criança. A sucção digital é outro fator influenciador da má formação da face, este pode ser antecedido pela mamadeira e chupeta. O conhecimento sobre o desenvolvimento facial correto ajuda no reconhecimento de desvios da normalidade. Foi realizada uma revisão da literatura a fim de analisar e comparar os efeitos no crescimento facial entre os hábitos deletérios e a amamentação fisiológica. Muitos registros de malformações causadas por hábitos deletérios foram encontrados. Conclui-se que a amamentação natural ainda é a melhor forma de alimentação para crianças, e nenhuma outra opção será melhor que a fisiológica, sendo aconselhável evitar o uso dos demais(AU)

The adoption of pacifiers and bottles by parents can bring problems in the child's craniofacial development. Finger sucking is another factor influencing the malformation of the face, which can be preceded by the bottle and pacifier. Knowledge about correct facial development helps in recognizing deviations from normality. A literature review was carried out in order to analyze and compare the effects on facial growth between harmful habits and physiological breastfeeding. Many records of malformations caused by deleterious habits were found. It is concluded that natural breastfeeding is still the best form of feeding for children, and no other option will be better than the physiological one, being advisable to avoid the use of the others(AU)

Craniofacial abnormalities and malocclusion findings in sickle cell disease related to ethnic-racial populations: a critical review of the literature

Introduction: sickle Cell Disease (SCD) is an inherited, hematological, chronic disease that mostly affects racial/ethnic groups. The dental literature discusses SCD's oral symptoms, such as malocclusion and craniofacial abnormalities, without considering the significance of a racial/ethnic perspective. Objective: this article critically reviewed the findings of the studies based on a racial/ethnic standpoint and SCD landmarks. Sources of data: primary and secondary searches selected 146 studies from four scientific literature databases. Two reviewers independently extracted data from eleven included studies. Synthesis of data: most studies used lateral cephalometry and reported craniofacial abnormalities and malocclusions, such as maxillary protrusion, class II skeletal patterns, vertical facial growth patterns, convex facial profile, mandibular retrusion, and the posterior rotation of the jaw. However, there is no mention of racial or ethnic cephalometric patterns to support these findings in the studied populations. In addition, a misunderstanding occurs when overlooking the different periods of growth or ages within and between the studied groups. Furthermore, there is no mention of previous orthodontic treatment. By contrast, there is a lack of information about the medically compromised health status of people with SCD, such as the life period of SCD's diagnosis; the number and timing of blood transfusions; the medical history of hospitalizations, vaso-occlusive crises, or hydroxyurea use. Conclusion: racial and ethnic concerns for the diagnosis of malocclusions and craniofacial anomalies, as well as SCD landmarks, are underappreciated in the examined dental literature. Discarding them also demonstrates institutional racism.

Introdução: a doença falciforme é uma doença hematológica, hereditária, crônica, que afeta principalmente, a população negra, em escala global. Na literatura odontológica, os achados craniofaciais e oclusais relacionados à doença falciforme são discordantes, mas, em comum, desconsideram a perspectiva racial. Objetivo: este artigo revisou criticamente a literatura odontológica e discutiu os achados encontrados na perspectiva racial/étnica. Fonte dos dados: estudos primários e secundários selecionaram 146 ocorrências de quatro bases de dados da literatura científica. Dois revisores extraíram independentemente os dados dos onze estudos incluídos. Síntese dos dados: com base na cefalometria lateral, a maioria dos estudos concluiu que as anormalidades craniofaciais e maloclusões, como protrusão maxilar, padrão esquelético de classe II, padrão de crescimento facial vertical, perfil facial convexo, retrusão mandibular e rotação posterior da mandíbula foram os mais comuns achados para pessoas com doença falciforme. No entanto, ao considerar a perspectiva étnico-racial, não há menção na maioria dos estudos de ajustes dos padrões cefalométricos específicos para as populações racializadas, nem tampouco são consideradas características do grupo populacional e da doença falciforme em si, como sua severidade, o momento de vida em que o diagnóstico ocorreu, número e período de hemotransfusões, internações, crises vaso-oclusivas ou uso de hidroxiureia. Além disso, a ampla faixa etária em diferentes períodos de crescimento ósseo e a ausência de informação sobre tratamento ortodôntico prévio foram observadas. Conclusão: há omissão sobre considerações étnico-raciais para relatar anormalidades craniofaciais e maloclusões sobre doença falciforme na literatura odontológica revisada. Isto pode ser uma expressão do racismo.

Influencia del pie como receptor en la postura corporal, la simetría facial y cráneo-mandibular / The influence of foot as a receptor on body posture and on facial, mandibular and cranial symmetries

Introducción: Un apoyo plantar incorrecto puede considerarse un factor etiológico de asimetrías faciales y cráneo-mandibulares pues modifica, de forma instantánea, la relación entre el maxilar y la mandíbula. Por tanto, resulta vital identificar la etiología de estas asimetrías para establecer diagnósticos y tratamientos certeros. Objetivo: Determinar la influencia del apoyo plantar en la postura corporal, la simetría facial y cráneo-mandibular en adolescentes. Métodos: Se realizó un estudio descriptivo y transversal de enero a septiembre de 2019 con 180 adolescentes que asistieron al servicio de Ortodoncia de la Clínica Docente de Especialidades «Victoria de Santa Clara», los cuales cumplían con criterios de selección de la investigación. Se analizaron variables faciales, posturales y cefalométricas. Se determinó: la simetría facial mediante el análisis de líneas faciales, el apoyo plantar al calcular el índice cavitario, la postura corporal, según la prueba de Di Rocca, y la simetría mandibular con el método modificado de Kurt y Uysal. Se siguieron las normas éticas y fueron aplicadas la prueba de Fisher, la de McNemar, y la técnica de conglomerado. Resultados: Predominaron los adolescentes con apoyo plantar asimétrico y los pies varo. Del total de casos con asimetría facial, 72,53 % presentó apoyo plantar asimétrico, y 39,44 % planos biilíaco y biclavicular desequilibrados y divergentes. La asimetría mandibular se observó en el 56,11%, la mayoría con apoyo plantar asimétrico. Conclusiones: Se pudo constatar la influencia del apoyo plantar en la postura corporal, la simetría facial y cráneo-mandibular, pues se observó un alto grado de relación entre las variables estudiadas.

Introduction: an incorrect plantar support can be considered an etiological factor of facial, mandibular and cranial asymmetries since it instantly modifies the relationship between the maxilla and mandible. Therefore, it is vital to identify the etiology of these asymmetries to establish accurate diagnoses and treatments. Objective: to determine the influence of plantar support on body posture and on facial, mandibular and cranial symmetries in adolescents. Methods: a descriptive and cross-sectional study was carried out from January to September 2019 with 180 adolescents who were seen in the Orthodontics service at "Victoria de Santa Clara" Specialty Teaching Dental Clinic, who met the research selection criteria. Facial, postural and cephalometric variables were analyzed. Facial symmetry was determined through the analysis of facial lines, plantar support by means of cavity index, body posture according to the Di Rocca test, and mandibular symmetry with the modified method of Kurt and Uysal. Ethical standards were followed and Fisher's and McNemar's tests as well as clustering technique were applied. Results: adolescents with asymmetric plantar support and varus feet predominated. The 72.53% had asymmetric plantar support from the total cases with facial asymmetry, and 39.44% had unbalanced and divergent biiliac and biclavicular planes. Mandibular asymmetry was observed in 56.11%, mostly with asymmetric plantar support. Conclusions: the influence of plantar support on body posture and on facial, mandibular and cranial symmetries was posible to verify since a high degree of relationship was observed among the variables studied.

Factores asociados a la calidad de vida relacionada con la salud bucal en preescolares de una comunidad andina / Factors associated with oral health related-quality of life in preschoolers from an Andean community

Objective : To analyze the oral health status and its relationship with the quality of life of Andean children of the community of Paucarbamba in Huancavelica, Peru. Material and Methods : The observational, cross-sectional, and correlational study was conducted on a sample of 120 children aged 3-5 years. Early childhood caries was considered using the dmft index. In addition, presence and type of malocclusion were assessed. The oral health-related quality of life was measured by The Early Childhood Oral Health Impact Scale (ECOHIS) questionnaire. Univariate and bivariate analysis were performed. Linear regression and Spearman correlation were conducted to identify the factors that most explained the ECOHIS score. Results : Multiple linear regression by least squares method did not consider gender, age, malocclusion, and simplified oral hygiene index as significant. This analysis only included dmft index as significant (p<0.05) to explicate the ECOHIS score. The estimated regression model was ECOHIS score = 11.67 + 0.79*dmft, in which the score increased by 0,79 for each unit obtained of the dmft index, and the dmft in a R2 = 30% (p<0.001) explained the variability of the ECOHIS score achieved. Conclusions : There is a negative impact of dental caries on the quality of life of preschool children and their families in an Andean community in Paucarbamba, Peru.

Objetivo : Analizar el estado de salud bucal y su relación con la calidad de vida de los preescolares de una comunidad andina y vulnerable del Perú. Material y Métodos : El estudio observacional, correlacional y transversal se realizó en una muestra de 120 niños de 3 a 5 años. La caries de la primera infancia se determinó mediante el índice ceod. También se consideró la presencia y el tipo de maloclusión. El cuestionario Early Childhood Oral Health Impact Scale (ECOHIS) midió la calidad de vida relacionada con la salud bucal. Los factores y variables orales se analizaron de manera univariada y bivariada. Se realizó un análisis de correlación de Spearman y regresión lineal para identificar los factores y en qué medida explicaban la puntuación del cuestionario. Resultados : El análisis de regresión lineal múltiple por el método de mínimos cuadrados solo incluyó como significativa (p <0,05) la contribución de ceod para explicar la puntuación del cuestionario, dejando de lado variables como el sexo, la edad, la maloclusión y el índice de higiene bucal simplificado. El modelo de regresión estimado fue Puntuación del Cuestionario = 11,67 + 0,79*ceod, donde la puntuación del cuestionario aumentó en 0,79 por cada unidad ganada de ceod, y la variabilidad de las puntuaciones obtenidas se explica por el ceod en un R2 = 30% (p<0,001). Conclusiones : Existe un impacto de la caries dental en la calidad de vida de los preescolares de uma comunidade andina del Perú y sus familias.

Análisis de la calidad de vida relacionada con salud oral en adultos con maloclusión / Analysis of the Oral Health-Related Quality of Life in Adults with Malocclusion / Análise da qualidade de vida relacionada à saúde bucal em adultos com má oclusão

aquellos pacientes que requirieron tratamiento de ortodoncia informaron impactos negativos en su calidad de vida relacionada con salud oral, en comparación con aquellos pacientes conclusión normal. El objetivo fue analizar la calidad de vida relacionada con la salud oral en pacientes con diferentes niveles de severidad de maloclusión que acudieron a consultorios odontológicos públicos de Paraguay durante el 2017. Materiales y métodos: estudio transversal. Se midieron variables sociodemográficas (como sexo, edad, residencia y nivel de estudios) y variables clínicas (como diastema, máxima irregularidad anterior maxilar y mandibular, resalte incisal y mordida cruzada anterior). Se utilizó el cuestionario Perfil de Impacto de Salud Oral en su versión paraguaya (ohip-14Py) y el Índice de Estética Dental (IED). Resultados: formaron parte del estudio 269 pacientes, la mayoría mujeres (75.1 %). El puntaje IED fue de 31.6 ± 11.6. Se observó resalte incisal aumentado (>2 mm) en poco más de la mitad (52.4 %) y una baja frecuencia de mordida cruzada anterior (5.9 %) y mordida abierta (10.0 %). Al evaluar por dimensiones, la incapacidad psicológica (p = 0.028), social (p = 0.034) y la minusvalía (p = 0.552) aumentaron conforme el nivel de severidad de maloclusión, por lo que fueron estadísticamente significativas las dos primeras. Conclusión: conforme aumenta la gravedad de la maloclusión, disminuye significativamente la calidad de vida oral para las dimensiones incapacidad psicológica e incapacidad social.

Patients requiring orthodontic treatment reported negative impacts on oral health-related qual-ity of life compared to patients with normal occlusion. Objective: To analyze the oral health-related quality of life in patients with different levels of severity of malocclusion attending public dental offices in Paraguay in 2017. Methodology: This was a cross-sectional study. Both, the sociodemographic variables, like sex, age, res-idence, and educational level, and the clinical variables, like diastema, maximum anterior maxillary, and mandibular irregularity, incisal overhang, and anterior crossbite were measured. The Oral Health Impact Profile questionnaire was used in its Paraguayan version (ohip-14Py) and the Dental Aesthetic Index (ied) scale. Results: A total of 269 patients were a part of the study. Moreover, 75.1 % of them were women. The ied score was 31.4 ± 11.6. An increase in the incisal protrusion (>2 mm) was seen in 52.4 % of the patients. Whereas a low frequency of anterior crossbite and open bite were seen in 5.9 % and 10.0 % of the population, respec-tively. While conducting an evaluation based on the dimensions, the psychological disability (p = 0.028), social disability (p = 0.034), and handicap (p = 0.552) increased according to the level of severity of malocclusion, being statistically significant in the first two. Conclusion: As the severity of the level of malocclusion increases, the oral quality of life decreases for the psychological disability and social disability dimensions.

os pacientes que necessitaram de tratamento ortodôntico relataram impactos negativos na qualidade de vida relacionada à saúde bucal em comparação aos pacientes com oclusão normal. Objetivo:analisar a qualidade de vida relacionada à saúde bucal em pacientes com diferentes graus de severi-dade da má oclusão que compareceram a consultórios odontológicos públicos no Paraguai durante o ano de 2017. Metodologia: estudo transversal. Foram mensuradas variáveis sociodemográficas como sexo, idade, residência e escolaridade e variáveis clínicas como diastema, irregularidade anterior maxilar e mandibular máxima, sobressaliência incisal e mordida cruzada anterior. Foram utilizados o questioná-rio Perfil de Impacto em Saúde Bucal em sua versão paraguaia (ohip-14Py) e o Índice de Estética Dental (ied). Resultados: fizeram parte do estudo 269 pacientes, sendo a maioria mulheres (75,1 %). A pontuação do ied foi de 31,6 ± 11,6. Observou-se aumento da saliência incisal (>2 mm) em pouco mais da metade (52,4 %) dos pacientes, além de baixa frequência de mordida cruzada anterior (5,9 %) e mordida aberta (10,0 %). Ao avaliar por dimensões, a incapacidade psicológica (p = 0,028), incapacidade social (p = 0,034) e desvantagem (p = 0,552) aumentaram de acordo com o grau de severidade da má oclusão, sendo as duas primeiras estatisticamente significativas. Conclusão: à medida que a gravidade da má oclusão aumenta, a qualidade de vida oral diminui significativamente para as dimensões de incapacidade psicológica e incapacidade social.

Analysis of morphometric changes in the anterior alveolar bone in bimaxillary protrusion adult patients after retraction with cone-beam CT / 中华口腔医学杂志

Objective: To measure and analyze the morphometric changes in the anterior alveolar bone during treatment and retention stage after retraction in bimaxillary adults using cone-beam CT(CBCT). Methods: Fifteen adult patients, four males and 11 females, aged 19 to 28 years[(22.2±3.1) years], who have completed orthodontic treatment and extracted four first premolar teeth for retraction in the Department of Orthodontics, The Affiliated Stomatological Hospital of Nanchang University from January 2016 to December 2018 were selected. CBCT was taken to assess the labial and palatal vertical bone level, total bone thickness at crest area, middle root area and apical area in pre-treatment (T1), post-treatment (T2) and at follow-up (maintained for more than two years) (T3). The differences in alveolar bone morphology at different stages were compared by single factor repeated measure ANOVA, and Pearson correlation analysis was performed on the amount of alveolar bone change in treatment stage and retention stage. Results: There were statistically significant differences in the alveolar bone height of the palatal side of maxillary anterior teeth, the labial side of maxillary lateral incisors and canine among three time points (P<0.05). The height difference of palatal alveolar bone of anterior teeth in T1-T2 stage was statistically significant (P<0.05). Palatal alveolar bone of upper and lower central incisors decreased by (1.52±0.32) and (4.96±0.46) mm, respectively. The height difference of anterior palatal alveolar bone was statistically significant in T2-T3 stage(P<0.05), the palatal alveolar bone height of central incisors increased by (1.20±0.27) and (3.14±0.35) mm respectively. The height difference of palatal alveolar bone in the anterior teeth of T1-T3 stage was statistically significant (P<0.05), and the height of palatal alveolar bone of central incisors was decreased (0.33±0.11) and (1.82±0.39) mm, respectively. There were statistically significant differences in the thickness of the cervical and middle root alveolar bone of anterior teeth among three time points (P<0.05). The difference of alveolar bone thickness of the cervical and middle root of anterior teeth at T1-T2 was statistically significant (P<0.05). decreased by (0.63±0.10) and (0.67±0.09) mm in lateral incisors, respectively. In the T2-T3 stage, the alveolar bone thickness of the crest area of the lower anterior teeth was significantly different (P<0.05), the alveolar bone thickness of mandibular central incisor crest area increased (0.09±0.03) mm. There were statistically significant differences in alveolar bone thickness in crest area and middle root of the incisors during T1-T3 stage (P<0.05), among which the middle root decreased by (0.38±0.16) mm and (0.63±0.13) mm, respectively. There was no statistically significant difference in other areas (P>0.05). The change of alveolar bone height in palatal side of upper anterior teeth at T2-T3 was very strongly negatively correlated with the change in T1-T2. The change of alveolar bone height in labial side of upper anterior teeth and lingual side of lower anterior teeth and the thickness of incisor root and neck were moderately strongly negatively correlated (r≤-0.8, P<0.001), the change of alveolar bone height in labial side of upper anterior teeth and lingual side of lower anterior teeth and the thickness of incisor crest area were moderately strongly negatively correlated (-0.8<r≤-0.4, P<0.05). Conclusions: For adult patients after retraction, anterior alveolar bone decreased significantly. In the retention stage, the same degree of bone apposition will occur, but still have alveolar bone loss compared with pre-treatment. The amount of alveolar bone change in the retention stage correlated with the amount of alveolar bone change in the treatment stage.