Carbohydrate use and reduction in number of balance beam falls: implications for mental and physical fatigue.

BACKGROUND: Artistic Gymnastics is a sport where athletes are frequently fatigued. One element that might influence this aspect is carbohydrate, an important energy substrate for the muscles and the CNS. Our goal was to investigate the influence of fatigue over artistic gymnastics athlete's performance and the effects of a carbohydrate supplementation on their performance. METHODS: We evaluated 15 athletes divided in 2 groups (control and fatigue) from 12 to 14 years old in two different experimental days. On the first day (water day), they did 5 sets of exercises on the balance beam (experimental protocol) ingesting only water, CG (control group) warmed up before the experimental protocol and FG (fatigue group) did a fatigue circuit, warm up exercises and then the experimental protocol. On the second day (carbohydrate day), we used the same protocol but CG ingested a sugar free flavored juice and FG ingested a 20% concentration maltodextrin solution before the protocol on the balance beam. RESULTS: We observed a greater number of falls from the balance beam from the FG on the first day (5.40 ± 1.14 FG vs 3.33 ± 1.37 CG; p = 0.024) and a decrease in the number of falls on the second day (2.29 ± 1.25 FG water day vs 5.40 ± 1.14 FG carbohydrate day; p = 0.0013). Carbohydrate solution was able to supply muscle demands and improve the athlete's focus showed by the reduced number of falls.

Use of corticocancellous allogeneic bone blocks impregnated with bone marrow aspirate: a clinical, tomographic, and histomorphometric study.

The aim of this study was to evaluate the efficacy of allogeneic block grafts impregnated with autologous bone marrow in horizontal ridge augmentation therapy. Ten patients with severe ridge volume deficiency in the anterior maxilla were treated with horizontal ridge augmentation. The patients were randomized into two groups: Five patients, using two allogeneic block grafts, were in the control group, and five patients, using two allogeneic block grafts impregnated with autologous bone marrow, were in the test group. Hematologists collected 4 mL of bone marrow from the iliac crest of the patients in the test group immediately prior to the surgeries. The blocks were fixed using titanium screws to obtain rigid fixation and to standardize the reference points for measurement purposes. CT scans were obtained both preoperatively and six months postoperatively to allow evaluation of horizontal bone gain. After a healing period of six months, the sites were reopened and the screws were removed. Before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation. Tomographic and histomorphometric measurements were recorded. The test group demonstrated better tomographic results (P < 0.05) in augmenting alveolar thickness, with a mean value of 4.60 ± 1.43 mm (118.23 ± 56.93%), while the control group had bone gain of 2.15 ± 0.47 mm (49.91 ± 20.24%). Despite the different results in alveolar thickness gained between groups, all sites received dental implants. The histomorphometric analysis also showed better results (P < 0.05) in the amount of vital mineralized bone in the test group as compared to the control group. The findings of this study suggest that an autologous bone marrow aspirate can increase the regenerative potential of corticocancellous allogeneic bone grafts.

The comparative analysis of homologous fresh frozen bone and autogenous bone graft, associated or not with autogenous bone marrow, in rabbit calvaria: a clinical and histomorphometric study.

The aim of this study was to evaluate the potential of fresh frozen homologous and autogenous grafts, associated or not with autogenous bone marrow, to form bone. Sixty titanium cylinders were used, and were fixed to the skulls of 30 rabbits. These cylinders were filled with (A) autogenous bone (AM) autogenous bone associated with the bone marrow (H) fresh frozen homologous bone (HM) fresh frozen homologous bone associated with the bone marrow (M) pure autogenous bone marrow and (C) blood clot. The animals were sacrificed after 02 and 03 months. After clinical evaluation, the samples were stained with hematoxylin, eosin and Mallory Trichrome dyes for optical microscopy analysis and histomorphometric analysis. Experimental groups that received mineralized materials (A, AM, H, HM) showed the best bone formation results, presenting no statistical difference between them (P > 0.05). Groups that did not receive mineralized materials (M and C) showed the worst results (P < 0.05), but the M group showed better results than the C group. Most of the autogenous and homologous bone particles were resorbed and there was a larger amount of residual particles in the homologous graft (H, HM) when compared with the autogenous graft (A, AM; P < 0.05). These findings suggest that fresh frozen homologous grafts produced similar amounts of new bone when compared with the autogenous grafts. However, the amount of residual bone particles was larger in the homogenous groups, which may indicate a slower remodeling process. The homologous fresh frozen bone seems to be a good osteoconductive material. The use of only autogenous bone marrow showed better results when compared to the bood clot. However, this research indicates that association with mineralized materials is required.

Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.

PURPOSE: The aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction. MATERIALS: Thirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group. Hematologists collected 5 ml of bone marrow from the iliac crest of the patients in the test group immediately before the extractions. Following tooth extraction and elevation of a buccal full-thickness flap, titanium screws were positioned throughout the buccal to the lingual plate and were used as reference points for measurement purposes. The sockets were grafted with an autologous bone marrow in the test sites and nothing was grafted in the control sites. After 6 months, the sites were re-opened and bone loss measurements for thickness and height were taken. Additionally, before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation. RESULTS: The test group showed better results (P<0.05) in preserving alveolar ridges for thickness, with 1.14+/-0.87 mm (median 1) of bone loss, compared with the control group, which had 2.46+/-0.4 mm (median 2.5) of bone loss. The height of bone loss on the buccal plate was also greater in the control group than in the test group (P<0.05), 1.17+/-0.26 mm (median 1) and 0.62+0.51 (median 0.5), respectively. In five locations in the control group, expansion or bone grafting complementary procedures were required to install implants while these procedures were not required for any of the locations in the test group. The histomorphometric analysis showed similar amounts of mineralized bone in both the control and the test groups, 42.87+/-11.33% (median 43.75%) and 45.47+/-7.21% (median 45%), respectively. CONCLUSION: These findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction.