Reabsorción radicular apical externatras la ortodoncia: Factores clínicos ydiagnósticos y análisis de redes de genesrelacionados / External apical root resorption after orthodontic treatment: clinical and diagnostic factors and analysis of related gene networks

Introducción: La reabsorción radicular apical externa (EARR) provocada por las fuerzas ortodóncicas representa uno de los efectos iatrogénicos más indeseables del tratamiento. Se pretende establecer una relación entre las variables diagnósticas y clínicas del tratamiento con la aparición y severidad de la reabsorción radicular apical externa agresiva (aEARR). Adicionalmente, la red de interrelaciones genéticas sirve para la generación de hipótesis en la correlación de variaciones genéticas, previamente asociadas con aEARR, con otras enfermedades. Métodos: Se realizó un estudio de asociación mediante una selección de 240 pacientes clasificados en dos grupos, basándose en la presencia o ausencia de a EARR. Se realizó un análisis descriptivo y una regresión logística binaria condicional tipo backward entre las variables y el desarrollo de aEARR. Se seleccionaron 5 variantes (STAG2, RP1-30E17.2, P2RX7, SPP1 y TNFRSF11A) asociadas a una mayor predisposición al desarrollo de aEARR y se realizó un análisis de redes. Resultados: Exclusivamente la variable tiempo de tratamiento obtuvo resultados estadísticamente significativos (IC: 95%; p=0,007) en relación con la aEARR. En el análisis de redes se encontró relación de 4 variantes genéticas con diferentes etapas del proceso patológico de la EARR que se relacionaron con 6 patologías: artritis, osteoartrosis, enfermedad autoinmune, lupus eritematoso, hepatitis C y EARR. Conclusiones: El único factor que se asoció con una mayor prevalencia de aEARR es el tiempo de duración del tratamiento. Cualquier vía que pueda tener relación con el proceso inflamatorio y, por tanto, con el proceso reabsortivo, puede tener una implicación mayor/menor de manera directa o indirecta en el desarrollo de la EARR (AU)

Introduction: External apical root resorption (EARR) caused by orthodontic forces represents one of the most undesirable iatrogenic effects of treatment. The aim of this study is to establish a relation between the diagnostic and clinical variables of treatment with the appearance and severity of aggressive external apical root resorption (aEARR). Additionally, the network of genetic interrelationships offers the generation of hypotheses in the correlation of genetic variations, previously associated with aEARR, with other diseases. Methods: An association study was performed using a selection of 240 patients classified into two groups based on the presence or absence of aEARR. A descriptive analysis of the data along with a backward conditional binary logistic regression was performed between the variables and aEARR. Five variants (STAG2, RP1-30E17.2, P2RX7, SPP1 and TNFRSF11A) associated with an increased predisposition to aEARR were selected and network analysis was performed. Results: Only the treatment time variable obtained statistically significant results (CI: 95%; p=0.007) in relation to aEARR. In the network analysis, 4 genetic variants were found to be related to different stages of the pathological process of aEARR, which were associated with 6 pathologies: arthritis, osteoarthrosis, autoimmune disease, lupus erythematosus, hepatitis C and EARR. Conclusions: The only factor associated with a higher prevalence of aEARR is the treatment duration. Any pathway that may be related to the inflammatory process and therefore to the resorptive process may have a greater/lesser involvement directly or indirectly in the development of aEARR (AU)

Sub-clustering in skeletal class III malocclusion phenotypes via principal component analysis in a southern European population.

The main aim of this study was to generate an adequate sub-phenotypic clustering model of class III skeletal malocclusion in an adult population of southern European origin. The study design was conducted in two phases, a preliminary cross-sectional study and a subsequent discriminatory evaluation by main component and cluster analysis to identify differentiated skeletal sub-groups with differentiated phenotypic characteristics. Radiometric data from 699 adult patients of southern European origin were analyzed in 212 selected subjects affected by class III skeletal malocclusion. The varimax rotation was used with Kaiser normalization, to prevent variables with more explanatory capacity from affecting the rotation. A total of 21,624 radiographic measurements were obtained as part of the cluster model generation, using a total set of 55 skeletal variables for the subsequent analysis of the major component and cluster analyses. Ten main axes were generated representing 92.7% of the total variation. Three main components represented 58.5%, with particular sagittal and vertical variables acting as major descriptors. Post hoc phenotypic clustering retrieved six clusters: C1:9.9%, C2:18.9%, C3:33%, C4:3.77%, C5:16%, and C6:16%. In conclusion, phenotypic variation was found in the southern European skeletal class III population, demonstrating the existence of phenotypic variations between identified clusters in different ethnic groups.

Effectiveness of Biology-Based Methods for Inhibiting Orthodontic Tooth Movement. A Systematic Review.

INTRODUCTION: Several experimental studies in the literature have tested different biology-based methods for inhibiting or decreasing orthodontic tooth movement (OTM) in humans. This systematic review investigated the effects of these interventions on the rate of tooth movement. STUDY DESIGN: Electronic [MedLine; SCOPUS; Cochrane Library; OpenGrey;Web of Science] and manual searches were conducted up to January 26th, 2016 in order to identify publications of clinical trials that compared the decreasing or inhibiting effects of different biology-based methods over OTM in humans. A primary outcome (rate of OTM deceleration/inhibition) and a number of secondary outcomes were examined (clinical applicability, orthodontic force used, possible side effects). Two reviewers selected the studies complying with the eligibility criteria (PICO format) and assessed risk of bias [Cochrane Collaboration's tool]. Data collection and analysis were performed following the Cochrane recommendations. RESULTS: From the initial electronic search, 3726 articles were retrieved and 5 studies were finally included. Two types of biology-based techniques used to reduce the rate of OTM in humans were described: pharmacological and low-level laser therapy. In the first group, human Relaxin was compared to a placebo and administered orally. It was described as having no effect on the inhibition of OTM in humans after 32 days, while the drug tenoxicam, injected locally, inhibited the rate of OTM by up to 10% in humans after 42 days. In the second group, no statistically significant differences were reported, compared to placebo, for the rate of inhibition of OTM in humans after 90 days of observation when a 860 nm continuous wave GaAlA slow-level laser was used. CONCLUSIONS: The currently available data do not allow us to draw definitive conclusions about the use of various pharmacological substances and biology-based therapies in humans able to inhibit or decrease the OTM rate. There is an urgent need for more sound well-designed randomized clinical trials in the field.

[When to start orthodontic treatment]. / Cuándo comenzar un tratamiento de ortodoncia.

We are frequently ashed by patient and dentist what the best age is to begin orthodontic treatment. In this article we will try to classify what the best age to begin treatment is, according to the type of malocclusion.