RESUMO
Introduction: The loss of dental elements can lead to excessive bone loss in the posterior maxillary segments, which can limit the placement of dental implants in that area, the pneumatization of the maxillary sinus and the absence of dental elements to keep the bone active are some of the main causes. Among the wide range of available grafting materials, bovine hydroxyapatite has been extensively studied and has shown excellent clinical and histological results. Materials and methods: A total of 17 maxillary sinus floor elevations were performed (n = 8 Osteodens, n = 9 Bio-Oss). After a healing period of 6 to 8 months, a block of the grafted area was obtained using trephines and analyzed by histomorphometry. Results: The percentage of neoformed bone tissue was higher for Bio-Oss (39.0% ± 11.1) compared to Osteodens (33.4% ± 8.3), while the remaining graft values were slightly lower in Bio-Oss compared to Osteodens (16.3% ± 11.2 and 20.8% ± 12.1, respectively). The proportion of connective tissue was similar in both groups (44.7% Bio-Oss and 45.8% Osteodens). Age, gender, and residual height of the sinus floor did not show statistically significant differences. Conclusions: In this study, both graft materials (Bio-Oss and Osteodens) showed no statistically significant differences in their ability to regenerate suitable bone tissue for implant placement after 6 months of healing. Further studies with a larger sample size are needed to validate these results.
Introducción: La pérdida de elementos dentarios puede provocar una excesiva pérdida ósea en los segmentos maxilares posteriores, lo que puede limitar la colocación de implantes dentarios en esa zona, la neumatización del seno maxilar y la ausencia de elementos dentarios que mantengan el hueso activo son algunas de las principales causas. Entre la amplia gama de materiales de injerto disponibles, la hidroxiapatita bovina ha sido ampliamente estudiada y ha mostrado excelentes resultados clínicos e histológicos. Materiales y métodos: Se realizaron un total de 17 elevaciones del suelo del seno maxilar (n = 8 Osteodens, n = 9 Bio-Oss). Tras un periodo de cicatrización de 6 a 8 meses, se obtuvo un bloque de la zona injertada mediante trépanos y se analizó mediante histomorfometría. Resultados: El porcentaje de tejido óseo neoformado fue mayor en Bio-Oss (39,0% ± 11,1) en comparación con Osteodens (33,4% ± 8,3), mientras que los valores del injerto remanente fueron ligeramente inferiores en Bio-Oss en comparación con Osteodens (16,3% ± 11,2 y 20,8% ± 12,1, respectivamente). La proporción de tejido conjuntivo fue similar en ambos grupos (44,7% Bio-Oss y 45,8% Osteodens). La edad, el sexo y la altura residual del piso sinusal no mostraron diferencias estadísticamente significativas. Conclusiones: En este estudio, ambos materiales de injerto (Bio-Oss y Osteodens) no mostraron diferencias estadísticamente significativas en su capacidad para regenerar tejido óseo adecuado para la colocación de implantes tras 6 meses de cicatrización. Se necesitan más estudios con un tamaño de muestra mayor para validar estos resultados.
RESUMO
This study aimed to evaluate the intestinal mucosa of the duodenum and jejunum of Walker-256 tumor-bearing rats supplemented with L-glutamine. Thirty-two male 50-day-old Wistar rats (Rattus norvegicus) were randomly divided into four groups: control (C), control supplemented with 2 % L-glutamine (GC), Walker-256 tumor (WT), and Walker-256 tumor supplemented with 2 % L-glutamine (TWG). Walker-256 tumor was induced by inoculation viable tumor cells in the right rear flank. After 10 days, celiotomy was performed and duodenal and jejunal tissues were removed and processed. We evaluated the cachexia index, proliferation index, villus height, crypt depth, total height of the intestinal wall, and number of goblet cells by the technique of periodic acid-Schiff (PAS). Induction of Walker-256 tumor promoted a reduction of metaphase index in the TW group animals, which was accompanied by a reduction in the villous height and crypt depths, resulting in atrophy of the intestinal wall as well as increased PAS-positive goblet cells. Supplementation with L-glutamine reduced the tumor growth and inhibited the development of the cachectic syndrome in animals of the TWG group. Furthermore, amino acid supplementation promoted beneficial effects on the intestinal mucosa in the TWG animals through restoration of the number of PAS-positive goblet cells. Therefore, supplementation with 2 % L-glutamine exhibited a promising role in the prevention of tumor growth and cancer-associated cachexia as well as restoring the intestinal mucosa in the duodenum and jejunum of Walker-256 tumor-bearing rats.
