ABSTRACT
BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the effect of radiotherapy on the osseointegration of dental implants in the tibia and the action of platelet-rich plasma (PRP) as an adjuvant therapy. MATERIAL AND METHODS: A total of 18 rabbits received two implants in each tibial epiphysis, totalizing 72 implants. The control group (group I) was composed by six rabbits and did not receive radiotherapy. The test groups (II and III) received a single dose of 1727 cGy. Group II was composed by six irradiated animals and group III by six animals that received irradiation and PRP during implant placement. The implant success rate, the bone-implant contact (BIC), and the bone volume were analyzed. RESULTS: There was no osseointegration in four of the implants, three in group II and one in group III. Total BIC was significantly higher in group I, when compared to the other groups. There was a significant difference of osteoid BIC only between irradiated animals (group II, 8.5%; group III, 4.7%; p = 0.001). On the other hand, the mineralized BIC was significantly higher in group I. Furthermore, group II had a lower mineralized BIC than group III (p = 0.002). Bone volume was higher in the control group (41.3%), followed by group III (33.4%) and II (25.1%), with differences between groups I and II (p = 0.001) and groups II and III (p = 0.022). CONCLUSIONS: The present study showed that both the bone volume and BIC were higher in the control group. However, the failure rates of the implants were low in both irradiated groups. The PRP was a positive adjuvant in the osseointegration process.
Subject(s)
Dental Implants , Osseointegration/radiation effects , Tibia/radiation effects , Animals , Dental Implantation, Endosseous/methods , Dental Restoration Failure , Male , Rabbits , Tibia/surgery , TitaniumABSTRACT
Camu-camu, es un árbol frutal, oriundo de la amazonía sudamericana que crece en las orillas anegables de ríos amazónicos. Pertenece al género Myrciaria, especie dubia. Presenta gran importancia nutritiva. Su alto contenido en ácido ascórbico (2780 mg/100 g de pulpa) le confieren propiedades antioxidantes. Objetivo: Evaluar la toxicidad subaguda (30 días) del Camu-camu. Material y método: Utilizamos 33 ratas albinas, macho, Holtzman, distribuidas en 3 grupos equitativos: Grupo I (grupo control), se le administró agua destilada, Grupo II y Grupo III, se les administró por vía oral el extracto seco de Camu-camu a las dosis de 100 y 200mg/Kg, respectivamente. Al inicio del experimento (basal), a las 15 y a los 30 días, se determinó: hemoglobina, WBC, urea, albúmina, creatinina, proteínas GGT, TGP, TGO, en sangre, y peso corporal; además, se realizó el examen histológico de hígado, riñones, bazo y estómago al finalizar el estudio (30 días). Resultados: Los valores de hemoglobina, albúmina y proteínas, fueron mayores que las del grupo control (p<0.05); a su vez, los valores de GGT fueron menores que los del grupo control (p<0.05). No encontramos evidencias de toxicidad sub-aguda, en ninguno de los 2 grupos expuestos, en el examen histopatológico. Conclusión: El Camu-camu, a las dosis y formas de administración, del presente trabajo, carece de efectos tóxicos para las ratas.
Camu-camu, is a native fruit tree of the South American jungle and grows at the borders of amazonian rivers. It belongs to Myrciaria generous and dubia specie and has a great nutritional importance. Contains a high amounts of ascorbic acid, (2780mg/100g of pulp), that is why it is good antioxidant. Objective: To evaluate the subacute toxicity of the atomized Camu-camu. Material and method: We used 33 Holtzman albino male rats, distributed in 3 equitable groups: Group I, the control group, only received distilled water, Groups II and III received 100 and 200 mg/Kg of Camu-camu, respectively. Blood samples were taken for biochemical analysis at the beginning, 15th and 30th days (at the end), to determinate Hb, WBC, urea, albumin, total proteins, creatinine, GGT, TGP, TGO and the weight of the animals; we also do the histological examination of liver, kidneys, spleen and stomach at the end of the experiments (day 30th). Results: The values of albumin, total proteins and hemoglobin were higher than the control group (p<0.05) while the values of GGT were lower that control group (p<0.05). We didnÆt find evidences of subacute toxicity in any of the 2 groups exposed to Camu-camu in the histopathological examination. Conclusion: Camu camu hadn´t toxic effect, in rats, with oral administration during 30 days.