Evaluation of anterior open-bite treatment with occlusal adjustment

Introduction: The purpose of this study was to evaluate the cephalometric and occlusal changes, the functional occlusion, and the dentinal sensitivity of anterior open-bite treatment with occlusal adjustment. Methods: The sample comprised 20 patients who experienced relapse of the anterior open bite (mean, -1.06 mm). Occlusal adjustment was performed until a positive overbite was established. Cephalometric changes were evaluated on lateral cephalograms taken before and after the occlusal adjustment. The functional occlusion analysis consisted of evaluating immediate anterior and canine guidance and the number of teeth in contact before and after the procedure. Dentinal sensitivity was evaluated before, shortly after, and 4.61 months after the occlusal adjustment. Pretreatment and posttreatment cephalometric changes and the number of teeth in contact were compared with dependent t tests. Percentages of anterior and canine guidance before and after the adjustment procedure were compared with the McNemar test. To compare dentinal sensitivity at several stages, the nonparametric Friedman test was used, followed by the Wilcoxon test. Results: Significant increases in overbite and mandibular protrusion were seen, as were significant decreases in apical base discrepancy, facial convexity, and growth pattern angles. The percentages of immediate anterior and canine guidance increased significantly, as did the number of teeth with occlusal contacts. Dentinal sensitivity increased immediately after the adjustment but decreased to normal levels after 4.61 months. Conclusions: Occlusal adjustment is a viable treatment alternative for some open-bite patients; it establishes positive vertical overbite and improves the functional occlusion with only transient dentinal sensitivity.

Assessment of matrix metalloproteinase (MMP)-2, MMP-8, MMP-9, and their inhibitors, the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in obese children and adolescents

Objectives: To compare the circulating levels of matrix metalloproteinase (MMP)-8, pro-MMP-2, pro-MMP-9, and total MMP-9, their endogenous inhibitors, the tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2, and the MMP-8/TIMP-1, MMP-9/TIMP-1, and MMP-2/TIMP-2 ratios in normotensive obese children and adolescents with those found in non obese children and adolescents. Design and methods: We studied 40 obese and 40 non obese (controls) children and adolescents in this cross-sectional study. MMP and TIMP concentrations were measured in plasma samples by gelatin zymography and ELISA. Results: Obese children and adolescents had higher circulating MMP-8 concentrations, lower plasma TIMP-1 concentrations, and higher MMP-8/TIMP-1 ratios than non obese controls (P < 0.05). We found no differences in pro-MMP-9 or total MMP-9 levels, or in MMP-9/TIMP-1 ratios between groups (P > 0.05). While we found no significant differences in pro-MMP-2 levels (P > 0.05) obese Subjects had higher TIMP-2 concentrations and lower pro-MMP-2/TIMP-2 ratios (P < 0.05) than non obese controls. Conclusions: In conclusion, we found evidence indicating higher net MMP-8 (but not MMP-9 and MMP-2) activity in childhood obesity. The increased MMP-8 levels found in obese children suggest a possibly relevant pathophysiological mechanism that may be involved in the increase of cardiovascular risk associated with childhood obesity. (c) 2009 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.