Surgical Treatment of Severe Frontal Bone Fracture

Craniofacial trauma can lead to several complications. The combined fractures of anterior and posterior walls of the frontal bone are almost always followed by lesions in nasofrontal orifices and disruption of nasofrontal ostia or ducts, a significant factor for the development of early and late complications after sinus fractures. This article reports a case of trauma patient, who underwent neurological evaluation and at first showed good general condition. Computed tomography noted fracture of the anterior and posterior walls of the frontal sinus and small foci of pneumocephalus in the cerebral cortex. The patient was monitored periodically and 9 days after trauma showed increased areas of pneumocephalus in prefrontal cortex, cerebrospinal fluid draining, and large dura mater lesion, with signs of necrosis and inflammation (meningitis). The necrotic tissues were removed, and dura mater was repaired through the approximation with resorbable wire polyglactin 910 5-0, oxidized cellulose application, and bonding with human fibrin sealant (fibrinogen, thrombin, and calcium chloride). Sinusectomy, frontal sinus, and nasofrontal duct obliteration with pedicled pericranium flap were performed. Tomographically, a reanatomization was noted in frontal region, and a 12-month follow-up showed no complication. The use of fibrin glue to repair dura mater lacerations, as well as the pedicle pericranium flap for frontal sinus and nasofrontal duct obliteration, is an efficient method for treating fractures of the frontal bone.

Peritoneal reactivity evaluation in horses subjected to experimental small colon enterotomy and treated with subcutaneous heparin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of dipyrone, meloxicam, or the combination on hemostasis in conscious dogs

To compare the effects of dipyrone, meloxicam, and of the combination of these drugs on hemostasis in dogs. Prospective, blinded, randomized crossover study. Research laboratory at a veterinary teaching hospital. Six adult dogs. Animals received 4 intravenous treatments with 15-day washout intervals: control (physiological saline, 0.1 mL/kg), meloxicam (0.2 mg/kg), dipyrone (25 mg/kg), and dipyrone-meloxicam (25 and 0.2 mg/kg, respectively). A jugular catheter was placed for drug injection and for collecting samples for whole blood platelet aggregation (WBPA) and thromboelastometry assays at baseline, 1, 2, 3, 5, and 8 hours after treatment administration. The percent change from baseline of lag time and of the area under the curve (AUC) of impedance changes in response to collagen-induced platelet activation were recorded during WBPA. Thromboelastometry-derived parameters included clotting time, clot formation time, alpha-angle, and maximum clot firmness. The buccal mucosal bleeding time was evaluated by a blinded observer at baseline, 1, 3, and 5 hours after treatment injection. No significant changes in WBPA and thromboelastometry were recorded in the control treatment. Dipyrone significantly (P < 0.05) increased the lag time for 2 hours and decreased the AUC for 3 hours after injection. Meloxicam did not alter WBPA. Dipyrone-meloxicam significantly increased lag time for 2 hours and decreased the AUC for 5 hours after treatment injection. Experimental treatments did not differ from the control treatment for thromboelastometry and buccal mucosal bleeding time. While meloxicam does not alter hemostasis by the methods evaluated, dipyrone inhibits platelet aggregation for up to 3 hours. Meloxicam-dipyrone combination causes more prolonged inhibition of platelet function than dipyrone alone. Decreased platelet aggregation induced by dipyrone and dipyrone-meloxicam does not appear to impact the viscoelastic properties of the blood clot nor increase the risk of bleeding in dogs without preexisting hemostatic disorders.

Evaluation of crystallized biosilicate in the reconstruction of calvarial defects

The objective of this study was to assess the bone repair process of crystallized Biosilicate in surgically created defects on rats' calvaria. This biomaterial was recently developed for odontological use. We used fifteen rats (rattus norvegicus albinus, Wistar), and two 5 mm surgical defects were performed on each of them; the defects were made with trephine drill on the calvarium region prior to the biomaterial placement. Groups were divided as follows: Group 1-defect filled with clot; Group 2-defect filled with crystallized Biosilicate. After 7, 14 and 28 days the animals were killed, the parts were retrieved and slides were prepared for histological studies. Bone formation was satisfactory in all groups, with direct contact between biomaterial surface and bone and absence of infection signs. The 28 days periods showed better results, and statistically significant difference between Clot Group (90.2 %) and Biosilicate (58 %; p = 0.002) was seen, regarding presence of bone tissue on the surgical defects. Our study revealed that defects filled with clot present better results on bone formation compared to crystallized Biosilicate, which is considered a biocompatible material with favorable osteoconductive properties.

Bone Ceramic® at implants installed immediately into extraction sockets in the molar region: an experimental study in dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise proteômica do plasma sanguíneo e crioprecipitado de búfalos Bubalus Bubalis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do selante de fibrina como arcabouço para células tronco em fígados cirróticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Thrombocytopenia and platelet hypoaggregation induced by Bothrops asper snake venom Toxins involved and their contribution to metalloproteinase-induced pulmonary hemorrhage

Thrombocytopenia and platelet dysfunction occur in patients bitten by Bothrops sp snakes in Latin America. An experimental model was developed in mice to study the effects of B. asper venom in platelet numbers and function. Intravenous administration of this venom induces rapid and prominent thrombocytopenia and ex vivo platelet hypoaggregation. The drop in platelet numbers was primarily due to aspercetin, a protein of the C-type lectin family which induces von Willebrand factor-mediated platelet aggregation/agglutination. In addition, the effect of class P-III hemorrhagic metalloproteinases on the microvessel wall also contributes to thrombocytopenia since jararhagin, a P-III metalloproteinase, reduced platelet counts. Hypoaggregation was associated with the action of procoagulant and defibrin(ogen)ating proteinases jararacussin-1 (a thrombin-like serine proteinase) and basparin A (a prothrombin activating metalloproteinase). At the doses which induced hypoaggregation, these enzymes caused defibrin(ogen)ation, increments in fibrin(ogen) degradation products and D-dimer and prolongation of the bleeding time. Incubation of B. asper venom with batimastat and α 2-macroglobulin abrogated the hypoaggregating activity, confirming the role of venom proteinases in this effect. Neither aspercetin nor the defibrin(ogen)ating and hypoaggregating components induced hemorrhage upon intravenous injection. However, aspercetin, but not the thrombin-like or the prothrombin-activating proteinases, potentiated the hemorrhagic activity of two hemorrhagic metalloproteinases in the lungs. © 2005 Schattauer GmbH, Stuttgart.

Regeneração óssea guiada com o uso de membrana de copolímero PLA/PGA em levantamento da membrana do seio maxilar: estudo experimental com análises histomorfométrica e imunoistoquímica

Pós-graduação em Odontologia - FOA

Estudo histomorfométrico do processo de cicatrização óssea em defeitos cirúrgicos de camanho crítico em calvárias de ratos preenchidos com polímero de mamona

Objectives: The aim of this study was to evaluate the behavior of the polymer histomorphometrically castor during the healing process of defects of critical size calvarial preparations in rats. Materials and Methods: Twenty animals underwent a surgical procedure that was to be held in the calvaria of each animal a critical defect of 8 mm in diameter with a drill trephine. The rats were divided into two groups according to the following procedures: group C received no treatment and the bone defect site was filled with blood clot, group M, the bone defect was filled with castor oil polymer particles. The animals were sacrificed 180 days after the surgical procedures. After routine laboratory procedures the specimens were subjected to analysis histomorphometric. Results: In groups C the newly formed bone tissue was well developed, with adjacent areas of osteoid matrix rich in osteoblasts, and restricted to the vicinity of the edges of the defect. In animals of group M was observed newly formed lamellar bone tissue restricted to the vicinity of the defect edges and particles of polymer Castor distributed throughout the defect. There was a higher percentage of newly formed bone area was statistically significant in group C compared to animals in group M. Conclusions: Within the limits of this study can conclude that the castor oil polymer is biocompatible and had kept the area during the healing of critical size defects in surgically prepared rat calvariae.

Bone regeneration in surgically created deffects filled with autogenous bone: epifluorescence microscopy analysis in rats

Although the search for the ideal bone substitute has been the focus of a large number of studies, autogenous bone is still the gold standard for the filling of defects caused by pathologies and traumas, and mainly, for alveolar ridge reconstruction, allowing the titanium implants installation. OBJECTIVES: The aim of this study was to evaluate the dynamics of autogenous bone graft incorporation process to surgically created defects in rat calvaria, using epifluorescence microscopy. MATERIAL AND METHODS: Five adult male rats weighing 200-300 g were used. The animals received two 5-mm-diameter bone defects bilaterally in each parietal bone with a trephine bur under general anesthesia. Two groups of defects were formed: a control group (n=5), in which the defects were filled with blood clot, and a graft group (n=5), in which the defects were filled with autogenous bone block, removed from the contralateral defect. The fluorochromes calcein and alizarin were applied at the 7th and 30th postoperative days, respectively. The animals were killed at 35 days. RESULTS: The mineralization process was more intense in the graft group (32.09%) and occurred mainly between 7 and 30 days, the period labeled by calcein (24.66%). CONCLUSIONS: The fluorochromes showed to be appropriate to label mineralization areas. The interfacial areas between fluorochrome labels are important sources of information about the bone regeneration dynamics.

Estudo histomorfométrico do processo de cicatrização óssea em defeitos cirúrgicos de tamanho crítico em calvárias de ratos preenchidos com polímero de mamona

Objectives: The aim of this study was to evaluate the behavior of the polymer histomorphometrically castor during the healing process of defects of critical size calvarial preparations in rats. Materials and Methods: Twenty animals underwent a surgical procedure that was to be held in the calvaria of each animal a critical defect of 8 mm in diameter with a drill trephine. The rats were divided into two groups according to the following procedures: group C received no treatment and the bone defect site was filled with blood clot, group M, the bone defect was filled with castor oil polymer particles. The animals were sacrificed 180 days after the surgical procedures. After routine laboratory procedures the specimens were subjected to analysis histomorphometric. Results: In groups C the newly formed bone tissue was well developed, with adjacent areas of osteoid matrix rich in osteoblasts, and restricted to the vicinity of the edges of the defect. In animals of group M was observed newly formed lamellar bone tissue restricted to the vicinity of the defect edges and particles of polymer Castor distributed throughout the defect. There was a higher percentage of newly formed bone area was statistically significant in group C compared to animals in group M. Conclusions: Within the limits of this study can conclude that the castor oil polymer is biocompatible and had kept the area during the healing of critical size defects in surgically prepared rat calvariae

O uso de drogas anticoagulantes e antiplaquetárias orais em pacientes cirúrgicos ambulatoriais: revisão de literatura

The oral anticoagulants (AOC) and platelet antiagregants are drugs used for the prevention of thromboembolic phenomena, such as pulmonary embolism in patients with atrial fribrilation heart valves, thrombosis and pulmonary embolism. For patients who are undergoing surgical procedures-dentistry were asked to discontinue the use of anticoagulants until the value of the INR remained = 2.0, that in order to avoid trans and hemorrhages in the postoperative period. However, the AOC can cause the formation of a clot, leading to obstruction of blood pathways. Thus, it became doubtful the medicine for surgery, in which local hemostatic measures would be sufficient to promote hemostasis. Thus, the objective of the review was to evaluate the risk of bleeding in patients AOC users that are subjected to surgical procedures, through a bibliographical survey carried out in relevant clinical studies published between 1990 and 2012, by the MedlinePubMed data. In this review of literature was concluded that the benefit of thromboembolism prevention overcomes the risk hemorrhage, therefore, it is recommended to keep the dose of anticoagulant therapy unchanged for patients undergoing oral surgery and implant dentistry, using appropriate INR levels with the assistance of local hemostatic. In addition, a refined surgical technique should be performed in these patients. With respect to the most invasive oral surgery, with a risk of bleeding, treatment may be necessary in conjunction with the medical staff.

A proporção de plasma rico em plaquetas/enxerto ósseo autógeno pode influenciar o reparo ósseo de defeito de tamanho crítico: estudo radiográfico em calvária de ratos

Introduction: It has been suggested that bone grafts combined with platelet rich plasma (PRP) present greater density than bone grafts without PRP after healing process. However, this result may depend on proportion PRP/autogenous bone (AB) graft used. Objective: The purpose of this study was to analyze radiographically the influence of the proportion PRP/particulate autogenous bone (AB) graft on bone healing in surgically created criticalsize defects (CSD) in rat calvaria. Material and method: 50 rats were divided into 5 groups: C, AB, AB/PRP-50, AB/PRP-100 and AB/PRP-150. A 5 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group AB the defect was filled with 0.01 mL of AB graft. In groups AB/ RP-50, AB/PRP-100 and AB/PRP-150 the defects were filled with 0.01 mL of AB graft combined with 50, 100 and 150 µL of PRP, respectively. All animals were euthanized at 30 days post-operative. Standardized radiographic images of the rat calvaria were obtained using Digora System (Soredex, Finland). The images were evaluated by three examiners using scores that indicated the percentage of radiopacity of the defect. The obtained data were subjected to statistical analysis (Kruskal-Wallis test, p < 0.05). Result: Group C presented radiopacity significantly lower than groups AB, AB/PRP-50, AB/PRP-100 and AB/PRP-150. Group AB/PRP-50 showed radiopacity significantly greater than groups AB/PRP-100 and AB. Conclusion: It can be concluded that the proportion PRP/AB graft influences bone healing in CSD in rat calvaria.

Efeito do ácido tranexâmico associado à cola de fibrina sobre o reparo ósseo: estudo histológico em ratos

The bone repair process is controlled by complex molecular mechanisms that involve systemic and local factors. Fibrin glue is derived from human plasma and mimics the final pathway of coagulation network. Tranexamic acid inhibits fibrinolysis and prevents or decreases the formation of degradation products of fibrin and fibrinogen. The purpose of this study was to evaluate histologically in rats the effect of tranexamic acid associated with the fibrin glue on bone healing. The experiment used 60 (n = 5) male rats in: GI: Control, GII: fibrin glue, GIII tranexamic acid and GIV /fibrin glue/tranexamic acid. Bone defect (2.5mm diameter) was created in right tibia. The animals were euthanized at 7,14 and 30 days postoperatively, and the pieces were processed with hematoxylin and eosin. The results showed at 7 days post-operative surgical cavity filled with dense connective tissue rich in fibroblasts, permeated by delicate neoformed bone trabeculae in percentage of 70-80% for GI, GII and GIII and GIV to 94.8%. At 14 days post-operative newly formed bone was found between 75-85% for GI, GII and GIII and percentage above 95% for GIV. At 30 days postoperative GI and GIV showed 95-100% of mature bone tissue; GII and GIII in percentage close to 80-90%. Based on the results and methodology is concluded that fibrin / tranexamic acid glue association has positive action on bone repair.