In vitro and in vivo evaluation of the biocompatibility of a calcium phosphate/poly(lactic-co-glycolic acid) composite.

This study assess the effects of bioceramic and poly(lactic-co-glycolic acid) composite (BCP/PLGA) on the viability of cultured macrophages and human dental pulp fibroblasts, and we sought to elucidate the temporal profile of the reaction of pulp capping with a composite of bioceramic of calcium phosphate and biodegradable polymer in the progression of delayed dentine bridge after (30 and 60 days) in vivo. Histological evaluation of inflammatory infiltrate and dentin bridge formation were performed after 30 and 60 days. There was similar progressive fibroblast growth in all groups and the macrophages showed viability. The in vivo study showed that of the three experimental groups: BCP/PLGA composite, BCP and calcium hydroxide (Ca(OH)(2)) dentin bridging was the most prevalent (90 %) in the BCP/PLGA composite after 30 days, mild to moderate inflammatory response was present throughout the pulp after 30 days. After 60 days was observed dentine bridging in 60 % and necrosis in 40 %, in both groups. The results indicate that understanding BCP/PLGA composite is biocompatible and by the best tissue response as compared to calcium hydroxide in direct pulp capping may be important in the mechanism of delayed dentine bridge after 30 and 60 days.

Estudio de las alteraciones maxilares en pacientes adultos con maloclusión de clase II, división 1ª, tratados con extracciones de primeros premolares superiores / No disponible

Se realizó un estudio cefalométrico, evaluando el comportamiento de las medidas SNA y A-NPerp con el propósito de verificar las alteraciones en la posición Anteroposterior del maxilar. La muestra utilizada estaba formada por 60 telerradiagrafias de 30 adultos con Clase II, división 1ª tomadas antes y después del tratamiento correctivo. En todos los casos fueron realizadas extracciones de los primeros premolares superiores. Observando el análisis descriptivo de los datos, se verificó que la medida SNA inicial disminuyó en media 1,66 grados cuando fue comparada con la magnitud SNA final. Por otro lado el valor A-Nperp presentó una disminución media de 2.6 mm. Se concluye que ambas medidas SNA y ANPerp representan el mismo comportamiento en los pacientes de la muestra, sugiriendo que cualquiera de las dos magnitudes analizadas expresan de forma similar la posición anteroposterior maxilar. El resultado del trabajo, demostró que en pacientes sin crecimiento, el tratamiento ortodóncico con extracciones de los primeros premolares superiores, induce una retrusión maxilar, con disminución del ángulo SNA y la magnitud A-NPerp (AU)

It was done a cefalometric study, analyzing the behavior of the SNA and ANperp measurements with the aim of verifying the alterations on the anteroposterior position of maxilla. The sample was 60 teleradiography on lateral pattern, at the beginning and end of treatment, from 30 adults, Class 11,1st division, who were submitted to corrective orthodontic treatment with extraction of both upper first premolars. After analyzing the results, we could observe that the SNA value reduced a mean rate of 1,7 degrees when compared to the final SNA value. TheA-Nperp showed a mean rate of 2,4 degrees of reduction. lt was concluded that the angular measurement SNA as well as the linear measurement ANperp had the same behavior and a strong correlation (r=O.698) in this sample, suggesting that any of these two magnitudes analyzed expressed similarly the antero-posterior position of the maxilla. The results of this paper showed that the orthodontic treatment on adults with extraction of the first premolars had a retraction of the antero-posterior position of the maxilla, with reduction of the SNA and A-Nperp values (AU)