Modelos fotoelásticos aplicados a la restauración dental

Objective: To improve the understanding of the changes generated by restorative procedures through photoelastic models. Dental reconstruction should be based on principles of occlusion in order not to cause premature contact points during preparation and restoration procedures that can lead to disorders such as occlusal trauma, TMJ dysfunction, or fractures. This paper presents a didactic method to objectively visualize occlusal loads and their distribution. Materials and methods: Photoelastic models of teeth and maxillary segments were made to visualize the effects of dental preparations and restorations, as well as the wear of premature contact points. Results: The direction, intensity and distribution of stresses in the crown and bone support were analyzed by photoelasticity. Conclusions: The technique allows us to visualize how the structures are affected from the cavity preparation, the different stresses with diamond or carbide burs, in addition to observing how a premature contact point not only affects the organ that contains it but also the surrounding structures.Objetivo:  Mejorar la comprensión de los cambios generados por los procedimientos restaurativos a través de modelos fotoelásticos. La reconstrucción dental debe fundamentarse en principios de oclusión para no provocar puntos prematuros de contacto durante los procedimientso de preparación y restauración que pueden provocar transtornos como el trauma oclusal, disfuncion de la ATM, o fracturas. En este documento se presenta un metodo didactico para visualizar de forma objetiva las cargas oclusales y su distribución. Materiales y métodos: Se realizaron modelos fotoelasticos de dientes y segmentos maxilares, para visualizar los efectos de las preparaciones dentales y restauraciones, asi como el desgaste de puntos prematuros de contacto. Resultados: Por fotoelasticidad se analizó la dirección, intensidad y distribución de esfuerzos en la corona y soporte óseo. Conclusiones: La tecnica permite visualizar cómo se afectan las estructuras desde la preparación cavitaria, los diferentes esfuerzos con fresas de diamante o carburo, además de observar cómo un punto prematuro de contacto no solo afecta al órgano que lo contiene sino a estructuras aledañas

Frecuencia de maloclusiones y su relación con hábitos parafuncionales en niños de Chihuahua, México

Aim: To assessment relationship between parafunctional habits frequency with dental malocclusions in patients between 8 and 12 years-old treated at the pediatric dentistry clinic of UACH School of Dentistry. Material and methods. A descriptive, cross-sectional retrolective study was carried out, taking as a study sample 1050 clinical files of patients between 8 and 12 years of age, both sexes, treated at the pediatric dentistry clinic of the Faculty of Dentistry of the UACH from 2016 to 2019. Information related to the diagnosis of malocclusions, parafunctional habits, as well as age and sex were considered. Results. Class I malocclusion occurred more frequently (67%), in terms of parafunctional habits, 40.8% presented onychophagia and 21.8% lip sucking, both were the most frequent. Regarding the presence of malocclusions by age, there was a statistically significant association (X2=3.109; p=0.024), but not with sex (X2MH=0.985; p=0.910). Conclusions. No was relationship between dental malocclusions and parafunctional habits frequency, as well with age and the presence of malocclusions and the year of registration. Objetivo. Establecer la asociación entre la frecuencia de hábitos parafuncionales con la presencia de maloclusiones en pacientes entre 8 y 12 años atendidos en la clínica de odontopediatría de la facultad de Odontología de la UACH. Material y Métodos. Se llevó a cabo un estudio descriptivo, transversal retrolectivo tomando como muestra de estudio 1050 expedientes clínicos de pacientes entre 8 y 12 años, ambos sexos, atendidos en la clínica de odontopediatría de la facultad de Odontología de la UACH en el periodo de 2016 a 2019. Se consideró la información relacionada con el diagnóstico de las maloclusiones, hábitos perniciosos, así como la edad y el sexo. Resultados. La maloclusión clase I se presentó con mayor frecuencia (67%), en cuanto a hábitos parafuncionales, el 40.8% presentó onicofagia y el 21.8% succión labial, ambos fueron los más frecuentes. Respecto a la presencia de maloclusiones por edad existió asociación relevancia estadísticamente significativa (X2=3.109; p= 0.024), no así con el sexo (X2MH=0.985; p=0.910). Conclusiones. No se demostró asociación entre la presencia de maloclusiones con la presencia de hábitos parafuncionales. Existió asociación entre la edad y la presencia de maloclusiones.&nbsp

Fluoride Consumption and Its Impact on Oral Health

Objective. The purpose of this study was to evaluate caries and dental fluorosis among Mexican preschoolers and school-aged children in a non-endemic zone for fluorosis and to measure its biological indicators. Methods. DMFT, DMFS, dmft, dmfs, and CDI indexes were applied. Fluoride urinary excretion and fluoride concentrations in home water, table salt, bottled water, bottled drinks, and toothpaste were determined. Results. Schoolchildren presented fluorosis (CDI = 0.96) and dental caries (DMFT = 2.64 and DMFS = 3.97). Preschoolers presented dmft = 4.85 and dmfs = 8.80. DMFT and DMFS were lower in children with mild to moderate dental fluorosis (DF). Variable fluoride concentrations were found in the analyzed products (home water = 0.18–0.44 ppm F, table salt = 0–485 ppm F, bottled water = 0.18–0.47 ppm F, juices = 0.08–1.42 ppm F, nectars = 0.07–1.30 ppm F, bottled drinks = 0.10–1.70 ppm F, toothpaste = 0–2,053 ppm F). Mean daily fluoride excretion was 422 ± 176 µg/24 h for schoolchildren and 367 ± 150 µg/24 h for preschoolers. Conclusions. Data from our study show that, despite values of excretion within an optimal fluoride intake range, the prevalence of caries was significant in both groups, and 60% of the 11- to 12-year-old children presented with dental fluorosis. In addition, variable fluoride concentrations in products frequently consumed by children were found

Photoelasticity for Stress Concentration Analysis in Dentistry and Medicine

Complex stresses are created or applied as part of medical and dental treatments, which are linked to the achievement of treatment goals and favorable prognosis. Photoelasticity is an optical technique that can help observe and understand biomechanics, which is essential for planning, evaluation and treatment in health professions. The objective of this project was to review the existing information on the use of photoelasticity in medicine and dentistry and determine their purpose, the areas or treatments for which it was used, models used as well as to identify areas of opportunity for the application of the technique and the generation of new models. A literature review was carried out to identify publications in dentistry and medicine in which photoelasticity was used as an experimental method. The databases used were: Sciencedirect, PubMed, Scopus, Ovid, Springer, EBSCO, Wiley, Lilacs, Medigraphic Artemisa and SciELO. Duplicate and incomplete articles were eliminated, obtaining 84 articles published between 2000 and 2019 for analysis. In dentistry, ten subdisciplines were found in which photoelasticity was used; those related to implants for fixed prostheses were the most abundant. In medicine, orthopedic research predominates; and its application is not limited to hard tissues. No reports were found on the use of photoelastic models as a teaching aid in either medicine or dentistry. Photoelasticity has been widely used in the context of research where it has limitations due to the characteristics of the results provided by the technique, there is no evidence of use in the health area to exploit its application in learning biomechanics; on the other hand there is little development in models that faithfully represent the anatomy and characteristics of the different tissues of the human body, which opens the opportunity to take up the qualitative results offered by the technique to transpolate it to an application and clinical learning

Parafunctional oral habits and its relationship with family structure in a mexican preschoolers group, 2013.

Introduction: Habit is any act acquired through experience and performed regularly and unconsciously. Parafunctional habits are resulting from the perversion of a normal function, acquired by repeated practice of an act that is not functional or necessary, may be signs of adjustment problems or inappropriate emotional expression. Its importance lies in the fact that they can interfere with the development of dental occlusion. Objective. To evaluate the prevalence of parafunctional oral habits and their possible association with the type of family, in a group of preschool children from eastern Mexico City. Methodology: Observational, descriptive and cross-sectional study was carrying on. Preschool children group and their parents were surveyed before an examiner calibration (k =0.87, p=0.001). The detection of different parafunctional habits was conducted in two stages: 1) application of a parent questionnaire and 2) clinical assessment of the child. Results and discussion. 57.7% of the studied population had at least one parafunctional oral habit. Onycophagia habit was the most prevalent. The relationship between prevalence of parafunctional habits with family type was significant (X2=87.439, p=0.0001). Conclusions: The prevalence of parafunctional habits was high which was associated with family type also the most frequent parafunctional habit onycophagia.Introducción: Un hábito es cualquier acto adquirido mediante la experiencia y realizado regular e inconscientemente. Los hábitos bucales parafuncionales son los que resultan de la alteración de una función normal, o los que se adquieren por la práctica repetida de un acto que no es funcional ni necesario, pudiendo ser signos de problemas de adaptación o de expresión emocional inadecuada. Su importancia radica en el hecho de que pueden  interferir con el desarrollo de la oclusión dental, razón por la cual el objetivo del presente estudio fue evaluar la prevalencia de hábitos bucales parafuncionales y su posible relación con la estructura familiar, en un grupo de preescolares de un Centro de Desarrollo Infantil del oriente de la Ciudad de México. Metodología. El estudio fue de carácter observacional, descriptivo y transversal, en el que 111 preescolares y sus padres fueron encuestados previa calibración de una examinadora (k=0.87, p=0.001). La detección de los diferentes hábitos bucales parafuncionales se realizó en dos etapas: 1) aplicación de un cuestionario al padre de familia y 2) valoración clínica del niño. Resultados y discusión: El 57.7% de la población estudiada presentó, al menos un hábito bucal parafuncional. La onicofagia fue el hábito de mayor prevalencia. La relación entre la prevalencia de hábitos parafuncionales con la estructura familiar resultó ser significativa (X2=87.439, p=0.0001). Conclusiones: La prevalencia de hábitos bucales parafuncionales fue alta la cual estuvo relacionada con la estructura familiar, asimismo, el hábito parafuncional más frecuente fue la onicofagia

Prevalence of temporomandibular joint disorders in a Mexican elderly group

Aim: To determine frequency and distribution of temporomandibular disorders (TMD) by age and sex in a group of elderly adults in Mexico City.  Material and methods: One hundred and fifty-four older adults in Mexico City were examined in a cross-sectional study. Subjects who had big edentulous gaps (absence of two or more teeth) or those who were fully edentulous, as well as those who refused to participate, were excluded from the study.  For the epidemiological survey, diagnostic criteria for Temporomandibular Disorders (DC/TMD), after standardization by a dentist (kappa=0.892), were considered. Results. A 33.1% had some type of TMD, being more common in people between 60 and 69 years old, variable with which it was related (Likelihood Ratio=21.553, p=0.006, X2MH=08.389, p=0.021). A 14.3% reported some type of facial trauma history, behavior that also was statistically significant (X2MH=13.566, p= 0.0001). Disorders that occurred most frequently were: disc displacement with reduction (62.8%) and disc displacement without reduction (9.8%). Conclusions. TMD occurred in one of every three subjects surveyed, showing a relationship with age and trauma history.Objetivo. Determinar la frecuencia y distribución de los trastornos temporomandibulares (TTM) por edad y sexo en un grupo de adultos mayores de la Ciudad de México. Material y métodos. Estudio de corte transversal. Se examinaron 154 adultos mayores de la Ciudad de México. Fueron excluidos del estudio a todos aquellos que presentaron brechas edéntulas amplias (ausencia de dos ó más dientes) o edentulismo total, así como aquellos que no aceptaron participar en el estudio. Para la encuesta epidemiológica se tomaron en cuenta los Criterios Diagnósticos de los Trastornos Temporomandibulares (CD/TTM), previa estandarización de una Cirujana Dentista (kappa=0.892). Resultados. El 33.1% presentó algún tipo de TTM, siendo más frecuente en personas entre 60 y 69 años variable con la cual estuvo relacionada (Razón de verosimilitud=21.553, p=0.006, X2MH=08.389, p=0.021). El 14.3% refirió algún tipo de antecedente traumático facial, comportamiento que también resultó ser estadísticamente significativo (X2MH=13.566, p=0.0001). Los trastornos que se presentaron con mayor frecuencia fueron: el desplazamiento del disco con reducción (62.8%) y el desplazamiento del disco sin reducción (9.8%). Conclusiones. Los TTM se presentaron en uno de cada tres adultos mayores examinados, existiendo una relación con la edad y los antecedentes traumáticos