Estrogen/Estrogen Receptor Alpha Signaling in Mouse Posterofrontal Cranial Suture Fusion

BACKGROUND: While premature suture fusion, or craniosynostosis, is a relatively common condition, the cause is often unknown. Estrogens are associated with growth plate fusion of endochondral bones. In the following study, we explore the previously unknown significance of estrogen/estrogen receptor signaling in cranial suture biology. METHODOLOGY/PRINCIPAL FINDINGS: Firstly, estrogen receptor (ER) expression was examined in physiologically fusing (posterofrontal) and patent (sagittal) mouse cranial sutures by quantitative RT-PCR. Next, the cranial suture phenotype of ER alpha and ER beta knockout (alphaERKO, betaERKO) mice was studied. Subsequently, mouse suture-derived mesenchymal cells (SMCs) were isolated; the effects of 17-beta estradiol or the estrogen antagonist Fulvestrant on gene expression, osteogenic and chondrogenic differentiation were examined in vitro. Finally, in vivo experiments were performed in which Fulvestrant was administered subcutaneously to the mouse calvaria. Results showed that increased ERalpha but not ERbeta transcript abundance temporally coincided with posterofrontal suture fusion. The alphaERKO but not betaERKO mouse exhibited delayed posterofrontal suture fusion. In vitro, addition of 17-beta estradiol enhanced both osteogenic and chondrogenic differentiation in suture-derived mesenchymal cells, effects reversible by Fulvestrant. Finally, in vivo application of Fulvestrant significantly diminished calvarial osteogenesis, inhibiting suture fusion. CONCLUSIONS/SIGNIFICANCE: Estrogen signaling through ERalpha but not ERbeta is associated with and necessary for normal mouse posterofrontal suture fusion. In vitro studies suggest that estrogens may play a role in osteoblast and/or chondrocyte differentiation within the cranial suture complex

Má oclusão Classe III de Angle com discrepância ântero-posterior acentuada Angle Class III malocclusion with severe anteroposterior disharmony

A má oclusão Classe III de Angle é caracterizada por uma discrepância dentária ântero-posterior, que pode ou não estar acompanhada por alterações esqueléticas. Em geral, o aspecto facial fica bastante comprometido, sendo justamente esse fator, na maioria das vezes, que motiva o paciente a procurar pelo tratamento. Este caso foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO), representando a categoria 4, ou seja, uma má oclusão com discrepância ântero-posterior acentuada, Classe III, com ANB menor ou igual a -2º, como parte dos requisitos para a obtenção do título de Diplomado pelo BBO.<br>Angle Class III malocclusion is characterized by an anteroposterior dental discrepancy which may or may not be accompanied by skeletal changes. In general, distressed by a significantly compromised facial aspect, patients tend to seek treatment. This case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO), as representative of Category 4, i.e., a malocclusion with severe anteroposterior discrepancy, Class III, and ANB Angle equal to or smaller than -2º, as part of the requirements for obtaining the BBO Diploma

Tratamento de Classe II, Divisão 1, com ausência congênita de incisivo lateral superior Treatment of Class II Division 1 with congenitally absent maxillary lateral incisor

Este relato mostra tratamento Ortodôntico efetuado em paciente portador de Classe II, Divisão 1, de Angle, com sobremordida profunda e agenesia do incisivo lateral superior esquerdo, em que o espaço foi fechado ortodonticamente e o canino ocupou o lugar do incisivo lateral. Os procedimentos adotados possibilitaram a obtenção de estética agradável e relação oclusal normal. A linha mediana não apresentou desvio ao término do tratamento e a discrepância vertical foi devidamente corrigida.<br>This case report demonstrates the orthodontic treatment of a patient who presented a Class II Division 1 malocclusion, deep overbite and congenitally absent maxillary left lateral incisor. The space was closed orthodontically and maxillary cuspid was positioned in the place of the maxillary lateral incisor. The treatment applied resulted in a pleasant esthetics and normal occlusal relationship. The midline was coincident at the end of treatment and vertical discrepancy was properly corrected