Navegando por Palavras-chave "osteogenesis"

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    Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft
    (Wiley-Blackwell, 2010-05-01) Pelegrine, Andre Antonio; Sorgi da Costa, Carlos Eduardo [UNIFESP]; Pizzigatti Correa, Maria Elvira; Comenalli Marques, Jose Francisco; Sao Leopoldo Mand Res Ctr; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)
    PurposeThe aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction.MaterialsThirteen 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.ResultsThe 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.ConclusionThese findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction.To cite this article:Pelegrine AA, da Costa CES, Correa MEP, Marques JFC Jr. Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.Clin. Oral Impl. Res. 21, 2010; 535-542.doi: 10.1111/j.1600-0501.2009.01891.x.
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    Repair of critical-size bone defects using bone marrow stromal cells: a histomorphometric study in rabbit calvaria. Part I: Use of fresh bone marrow or bone marrow mononuclear fraction
    (Wiley-Blackwell, 2014-05-01) Pelegrine, Andre Antonio [UNIFESP]; Aloise, Antonio Carlos [UNIFESP]; Zimmermann, Allan [UNIFESP]; Mello e Oliveira, Rafael de [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    ObjectivesThe aim of this study was to compare the bone healing observed after the use of (1) a scaffold enriched with fresh bone marrow, (2) a scaffold enriched with bone marrow mononuclear fraction, and (3) a scaffold alone.Material and methodsTwenty one rabbits were randomly divided into three groups of six animals and 1 group of 3 animals. Bilateral 12-mm diameter defects were created in the animals' parietal bones. in Control Group, the defects were filled with a xenograft alone (n=6); in Group 1, with a xenograft enriched with fresh bone marrow (n=6); in Group 2, with a xenograft enriched with bone marrow mononuclear fraction (n=6) and in Unfilled Group, nothing was grafted (n=3). in Groups 1, 2, and Control, one of the calvarial defects was randomly covered with a barrier membrane. the rabbits were sacrificed 8weeks after surgery, and their parietal bones were harvested and analyzed histomorphometrically.ResultsThe histomorphometric analysis showed no difference between Group 1 and the Control Group regarding non-vital mineralized tissue area, but Group 2 showed a statistically significant higher percentage than the Control Group (P<0.05) for both situations, with membrane (21.24 +/- 3.78% and 13.52 +/- 3.00%, respectively) and without membrane (20.91 +/- 2.01% and 13.08 +/- 1.72%, respectively). Group 2 showed the highest percentage of vital mineralized tissue area, followed by Group 1 and the Control Group (P<0.05) for both situations, with membrane (28.17 +/- 3.19%; 21.14 +/- 7.38% and 13.06 +/- 5.24%, respectively) and without membrane (21.13 +/- 0.55%; 12.45 +/- 6.34% and 6.56 +/- 1.20%, respectively). Group 2 showed the lowest percentage of non-mineralized tissue area, followed by Group 1 and Control Group (P<0.05) for both situations, with membrane (50.59 +/- 6.64%; 58.75 +/- 7.14% and 73.41 +/- 6.87%, respectively) and without membrane (57.97 +/- 1.91%; 71.74 +/- 6.63% and 80.37 +/- 2.67%, respectively). the sides in which the defects were covered with the barrier membrane showed better bone healing compared with the uncovered sides, in all groups (intragroup comparison, P<0.05). the Unfilled Group specimens showed no bone formation.ConclusionsBoth methods using bone marrow stromal cells contributed to enhancing bone healing, especially that using the bone marrow mononuclear fraction. the use of a barrier membrane seemed to have a synergistic effect.
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    RT-PCR standardization and bone mineralization after low-level laser therapy on adult osteoblast cells
    (Spie-int Soc Optical Engineering, 2014-01-01) Costa do Bomfim, Fernando Russo [UNIFESP]; Gonzalez Sella, Valeria Regina [UNIFESP]; Zanaga, Jessica Querido; Pereira, Nayara Simionatto; Andree Nouailhetas, Viviane Louise; Plapler, Helio [UNIFESP]; Choi, B.; Kollias, N.; Zeng, H.; Kang, H. W.; Wong, BJF; Ilgner, J. F.; Tearney, G. J.; Gregory, K. W.; Marcu, L.; Mandelis, A.; Universidade Federal de São Paulo (UNIFESP)
    Purpose: Osteoblasts are capable to produce different compounds directly connected to bone mineralization process. This study aims to standardize the reverse transcriptase polymerase chain reaction (RT-PCR) for adult osteoblasts to observe the effect of low level laser therapy on bone mineralization. Methods: Five-millimeter long fragments obtained from the mead femoral region of male Wistar rats were assigned into group A (n=10, laser) and group B (n=10, no laser), submitted to mechanic and enzymatic digestion. After 7 days, cultures of group A were irradiated daily on a single spot with a GaInAs laser, lambda=808nm, 200mW/cm(2), 2J/cm(2), bean diameter of 0,02mm, 5 seconds for 6 days. Group B was manipulated but received no laser irradiation. After 13 days the cells were trypsinized for 15 minute and stabilized with RNA later (R) for RNA extraction with Trizol (R). cDNA synthesis used 10 mu g of RNA and M-MLV (R) enzyme. PCR was accomplished using the beta-actin gene as a control. Another aliquot was fixed for Hematoxylin-Eosin and Von Kossa staining to visualize bone mineralization areas. Results: Under UV light we observed clearly the amplification of beta-actin gene around 400bp. HE and Von Kossa staining showed osteoblast clusters, a higher number of bone cells and well defined mineralization areas in group A. Conclusion: the cell culture, RNA extraction and RT-PCR method for adult osteoblasts was effective, allowing to use these methods for bone mineralization studies. Laser improved bone mineralization and further studies are needed involving osteogenesis, calcium release mechanisms and calcium related channels.