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.

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.

[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.