Consumo de matéria seca e desempenho de novilhas Nelore alimentadas com dietas contendo cana-de-açúcar hidrolisada / Dry matter intake and performance of Nellore heifers fed with hydrolyzed sugarcane

Objetivou-se avaliar o consumo de nutrientes e o desempenho de novilhas Nelore alimentadas com dietas contendo cana-de-açúcar in natura (CN) ou hidrolisada (CH) com 0,5% de Ca(OH)2 armazenada por 24, 48 e 72 horas. Foram utilizadas 24 novilhas com nove meses de idade e 119,6±8,1kg de peso corporal inicial. O delineamento experimental utilizado foi o inteiramente casualisado com quatro tratamentos e seis repetições. O consumo de matéria seca foi reduzido em 29% pela adição de Ca(OH)2, não sendo alterado pelo período de armazenamento da CH. O consumo de cálcio foi incrementado (P<0,05) pela utilização de CH nas dietas, mantendo níveis de ingestão aceitáveis. Novilhas alimentadas com CH armazenada por 24, 48 e 72 horas apresentaram, respectivamente, ganhos de peso 41, 30 e 35% inferior (P<0,05) àquelas alimentadas com CN. O tratamento da cana-de-açúcar com Ca(OH)2 não é recomendado para alimentação de novilhas Nelore, em virtude de limitar a ingestão e reduzir o ganho de peso.

The study aimed to evaluate the nutrients intake and performance of Nellore heifers fed with chopped sugarcane, fresh (FS) or treated (HS) with 0.5% of Ca(OH)2 and stored during 24, 48 or 72 hours. It was used twenty-four heifers with nine months age and 119.6±8.1kg of initial body weight. The experimental design was completely randomized with four treatments and six replications. The dry matter intake showed an average reduction of 29% by adding Ca(OH)2, and didn't change with the storage period. Calcium intake was increased by the use of HS in the diet, while maintaining acceptable levels of intake. Heifers fed with HS stored during 24, 48 and 72 hours had, respectively, average daily weight gain of 41, 30 and 35% lower than those fed with FS. The treatment of sugarcane with Ca(OH)2 is not recommended for feeding Nellore heifers, due to limited intake and lower weight gain.

Apexification with the use of calcium hydroxide.

After traumatic injuries the pulps of young permanent teeth often necrose. This occurs most commonly in the permanent maxillary incisors leaving the teeth with incomplete radicular development and open apices. In these cases treatment is aimed at promoting complete apical closure. At a later date a complete filling of the root canal is carried out in order to prevent inflammatory stimulators affecting the periapex. Apexification is a method of treatment intended to induce formation of a calcific barrier in an immaturely developed or pulpless tooth. The intent of apexification is to attain narrowing of the canal or closure of the apex. Apexification is indicated in young patients, for reasons such as trauma, fracture or caries involving the pulp require root canal treatment prior to the apex fully developing and closing.

The effect of calcium hydroxide placement on pH and calcium concentration in periapical environment: An in vitro study.

Aims: Comparing the calcium concentration and pH levels of Ca(OH) 2 medicament placing in pulp chamber and root canal. Materials and Methods: Ninety-nine extracted human mandibular second premolars were instrumented to size #40 k file. Nine teeth served as the control group and the remaining teeth were assigned into two groups. Group 1-Ca(OH) 2 was placed in the dried pulp chamber, while root canals remained wet with normal saline; group 2-Ca(OH) 2 was placed in dried root canals. In control group, canals remained wet without medication. Each group was divided into 3 sub-groups of 15 teeth in which pH and calcium concentration were measured in three intervals of 2 days, 1 week, and 2 weeks by pH meter and atomic absorption spectrometer system, respectively. Findings were assessed using Kruskal-Wallis and t-test. Results: At 1 and 2 weeks, the calcium concentration had increased without being significantly different from Ca(OH) 2 placed either in the root canal or in the pulp chamber. Ca(OH) 2 placed in the pulp chamber or root canal provided similar pH values (P=0.362). Conclusions: Placing Ca(OH) 2 in pulp chamber is as effective as placing it in the root canal.

Evaluation del cierre apical con hidróxido de calcio, MTA y plasma rico en factores de crecimiento in vivo / Evaluation of the apical closing with calcium hydroxide, MTA and PRGF

Objetivo. Observar la formación de un tope apical mediante el empleo de Ca(OH)2, MTA y PRGF colocado en dientes inmaduros de perros a un solo período de observación. Metodología. Fueron utilizados dos perros en los cuales se trabajó con 16 muestras. Este trabajo se realizó en dos tiempos operatorios, el primero para impedir el desarrollo normal del ápice radicular provocando una lesión apical colocando una torunda de algodón con placa dentobacteriana de humano durante dos meses, el segundo tiempo operatorio para colocar los materiales a probar formando cuatro grupos: 1. control (limpieza del conducto); 2. hidróxido de calcio (Ca(OH)2); 3. mineral trióxido agregado (MTA); 4. plasma rico en factores de crecimiento (PRGF). Siete meses después, los perros fueron sacrificados y las muestras preparadas para ser observadas al microscopio óptico. Resultados. Los resultados obtenidos fueron muy similares entre las muestras de su propio grupo. Grupo control: el ápice se encontró totalmente abierto y sin vías de reparación. Grupo del hidróxido de calcio: el ápice se encontró abierto pero en vías de reparación, formando un tejido de osteocemento o de tipo cementoide, pequeños focos de infiltrado inflamatorio. Mineral trióxido agregado: se observó un cierre total del ápice, con dentina bien organizada y con engrosamiento del cemento en la porción apical. Plasma rico en factores de crecimiento: ápice abierto en vías de reparación, tejido cementoide o de tipo osteocemento. Dentro de todo el conducto se observan fibras de colágeno, tejido conectivo laxo yalgunos vasos sanguíneos. Conclusiones. Con base a los resultados observados, sobresalen dos de los materiales utilizados, estos son el MTA por el cierre apical tan similar a la fisiología natural, y PRGF por el tejido formado dentro del conducto radicular; sin embargo el hidróxido de calcio también logra estimular la formación de tejido calcificado periapical

The objective of this work was to observe the formation of an apical top by means of the use of Ca(OH)2, MTA and PRGF placed in immature teeth of dogs to a single period of observation. Two dogs were used, in which 16 samples were worked. This work was made in two operating times, first to prevent the normal development of the apex, causing an injury placing a short portion of cotton with dentobacterian plaque of human during two months. In the second operating time the teeth were divided into four groups according to the materials to prove: 1. Control cleaning of the canal; 2. Calcium Hydroxide - Ca(OH)2; 3. Mineral Aggregate Trioxide; 4. Blood Plasma Rich in growth factors (PRGF). Seven months later, the dogs were sacrificed and samples were prepared to be observed in optical microscope. The obtained results were very similar among the samples of their own group. Control Group: the apex was totally open, without repair. Group of Ca(OH)2: the apex was open but on the way to repair, forming a weave of hard tissue, small centers of inflammatory infiltrate. MTA group: a total closing of the apex was observed, with organized affluent dentine, and thickening of cement in the apical portion. Plasma Rich in Growth Factors Group: apex opened on the way to repair, cement weave or a type of osteocement was present. Within all the canal, collagen fibers and connective tissue weave were observed and some blood vessels. Based on the observed results, they excel two of the used materials, these are the MTA similar to the natural physiology while PRGF by the weave formed within the root canal; nevertheless the Calcium Hydroxide also stimulates the calcified weave apical formation.

MMP and TIMP production in periodontal ligament fibroblasts stimulated by Prevotella nigrescens lipopolysaccharide / 대한치과보존학회지

The purpose of this study was to monitor the secretion of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) by human periodontal ligament (PDL) fibroblasts stimulated with Prevotella nigrescens lipopolysaccharide (LPS), and to examine the effect of calcium hydroxide treatment on P. nigrescens LPS. LPS was extracted and purified from anaerobically cultured P. nigrescens. PDL fibroblasts were stimulated by the LPS (0, 0.1, 1, 10 ug/ml) or LPS (10 ug/ml) pretreated with 12.5 mg/ml of Ca(OH)2 for 3 days, for various periods of time (12, 24, 48 h). Immunoprecipitation were performed for protein level analysis of MMP-1, MMP-2 and TIMP-1. Total RNA was isolated and real-time quantitative polymerase chain reaction (PCR) was performed for quantification of MMP-1 mRNA. According to this study, the results were as follows: 1. The production of MMP-1 by stimulation with P. nigrescens LPS increased in time-dependent manner, and showed maximum value at 48 h in both protein and mRNA level. But there was no dose-dependent increase. 2. MMP-2 production time-dependently increased when stimulated with 1 and 10 ug/ml LPS, but there was no dose-dependent increase. 3. TIMP-1 production increased to 24 h, but decreased at 48 h. It increased when stimulated with 0.1 and 1 ug/ml LPS, but suppressed at 10 ug/ml. 4. P. nigrescens LPS pretreated with Ca(OH)2 markedly downregulated MMP-1 gene expression.

MMP-1 and TIMP-1 production in MG-63 cells stimulated with Prevotella nigrescens lipopolysaccharide / 대한치과보존학회지

The purpose of this study is to monitor the secretion of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) produced by human osteosarcoma cell line (MG63) stimulated with Prevotella nigrescens lipopolysaccharides (LPS), and to compare the level of secretion before and after the treatment of calcium hydroxide on P. nigrescens LPS. LPS was extracted and purified from anaerobically cultured P. nigrescens. MG63 cells were stimulated by the LPS (0, 1, 10 microg/ml) or LPS (10 microg/ml) pretreated with 12.5 mg/ml of Ca(OH)2 for 3 days. Total RNA was isolated from the cell, and real-time quantitative polymerase chain reaction (PCR) was performed for quantification of MMP-1 and TIMP-1. The results were as follows. 1. MMP-1 mRNA expression at 48 hr was highly increased by stimulation with P. nigrescens LPS. The increase was dose-dependent. 2. When stimulated with 1 microg/ml of LPS, TIMP-1 mRNA expression was highly increased at 24 hr and 48 hr. However, TIMP-1 expression was suppressed at higher concentration (10 microg/ml). 3. When P. nigrescens LPS was pretreated with Ca(OH)2, MMP-1 and TIMP-1 gene expression was downregulated. The results of this study suggest that transcriptional regulation of MMP-1 and TIMP-1 by P. nigrescens LPS could be one of the important mechanisms in bone resorption of periapical inflammation. The result of calcium hydroxide on MMP-1 and TIMP-1 gene expression suppression shows that calcium hydroxide detoxified bacterial LPS and thus should be used the medication of choice for intracanal dressings in root canal infected with black-pigmented bacteria.