Institucion Universitaria Colegios De Colombia

Objective. This study assessed the neuropeptide Y (NPY) expression in healthy human dental pulp following tooth bleaching with three in-office hydrogen peroxide-based systems: Opalescence Boost© (Ultradent Products, South Jordan, UT), Pola Office© (SDI, Victoria, Australia), and Zoom© (Zoom! Bleaching System; Discuss Dental, Culver City, CA).
Materials and Methods. Forty dental pulps were collected from healthy premolars scheduled for extraction for orthodontic reasons. Teeth were divided into four groups containing ten healthy premolars each: Control group (n= 10): the teeth were not exposed to dental bleaching agents (healthy pulps assessed for normal/basal NPY values). Pola Office system group (n= 10): application of Pola office (35% H2O2) for 8 minutes. Opalescent Boost system group (n= 10): application of Opalescent Boost (40% H2O2) for 20 minutes. Zoom system group (n= 10): application of Zoom! (25% H2O2 + cold blue light) for 15 minutes. The investigators rigorously followed the manufacturer's instructions for all bleaching systems. Following the extractions, the pulpal tissue was collected, placed in a 4% formaldehyde solution in Eppendorf tubes, and processed. NPY levels were measured using enzyme-linked immunosorbent assay (ELISA).

The goal of this clinical trial is to conduct an in vivo study that allows to compare the periapical healing process of 3 different sealing cements through CBCT, as well as implement the evaluation of these lesions through volumetric measurements to provide high-level scientific information and thus have the possibility of being applied in the clinical dental practice, in patients attending UNICOC dental clinics between 2023 and 2024. The main question it aims to answer is:
* Do bioceramic sealer promote faster periapical healing due to their better sealing capacity and high bio-compatibility?
* Are there no differences between endodontic sealers in terms of apical healing? If there is a comparison group: Researchers will compare Bio-C Sealer (Bioceramic sealer) Zinc-oxide eugenol sealer and AH-Plus epoxy resin sealer to evaluate periapical healing after a six months follow-up of conventional endodontic therapy.
Coronal permanent restoration must be performed no later than 15 days after endodontic therapy.

The purpose of this study was to quantify the effect of moderate and severe orthodontic forces on Calcitonin gene-related peptide expression in the healthy human periodontal ligament.
Methodology: 90 human periodontal ligament samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. Prior to extraction, teeth were divided into 3 groups of 30 samples each: I) Untreated teeth control group; II) Moderate force group: A 56 g force was applied to the premolars for 7 days; and III) Severe force group: A 224 g force was applied to the premolars for 24 hours. All periodontal ligament samples were processed and CGRP was measured by radioimmunoassay.