Daniela Vieira Buchaim

Effect of low-level laser therapy (LLLT) on peripheral nerve regeneration using fibrin glue derived from snake venom.

OBJECTIVES The purpose of this study was to assess whether the adhesive permits the collateral repair of axons originating from a vagus nerve to the interior of a sural nerve graft, and whether low-level laser therapy (LLLT) assists in the regeneration process. MATERIALS AND METHODS Study sample consisted of 32 rats randomly separated into three groups: Control Group (CG; n=8), from which the intact sural nerve was collected; Experimental Group (EG; n=12), in which one of the ends of the sural nerve graft was coapted to the vagus nerve using the fibrin glue; and Experimental Group Laser (EGL; n=12), in which the animals underwent the same procedures as those in EG with the addition of LLLT. Ten weeks after surgery, the animals were euthanized. Morphological analysis by means of optical and electron microscopy, and morphometry of the regenerated fibers were employed to evaluate the results. RESULTS Collateral regeneration of axons was observed from the vagus nerve to the interior of the autologous graft in EG and EGL, and in CG all dimensions measured were greater and presented a significant difference in relation to EG and EGL, except for the area and thickness of the myelin sheath, that showed significant difference only in relation to the EG. CONCLUSIONS The present study demonstrated that the fibrin glue makes axonal regeneration feasible and is an efficient method to recover injured peripheral nerves, and the use of low-level laser therapy enhances nerve regeneration.

Effects of low-level laser therapy on autogenous bone graft stabilized with a new heterologous fibrin sealant.

Autogenous bone grafts are used to repair bone defects, and the stabilization is needed for bone regeneration. Laser photobiomodulation is a modality of treatment in clinical practice for tissue regeneration, and it has therapeutic effects as an anti-inflammatory, analgesic and modulating cellular activity. The aim of the present study was to evaluate the effects of low-level laser therapy (LLLT) on an autogenous bone graft integration process stabilized with a new heterologous fibrin sealant. Forty rats were divided into two groups: Autogenous Fibrin Graft (AFG, n=20), in which a 5mm dome osteotomy was conducted in the right parietal bone and the graft was adhered to the left side using fibrin sealant; and Autogenous Fibrin Graft Laser (AFGL, n=20), which was subjected to the same procedures as AFG with the addition of LLLT. The treatment was performed immediately following surgery and then three times a week until euthanasia, using an 830nm laser (30mW, 6J/cm(2), 0.116cm(2), 258.6mW/cm(2), 2.9J). Five animals from each group were euthanized at 10, 20, 30 and 40days postoperative, and the samples were submitted to histomorphological and histomorphometric analysis. Partial bone regeneration occurred, with new bone tissue integrating the graft to the recipient bed and small areas of connective tissue. Comparative analysis of the groups at the same intervals revealed minor interfaces in group AFGL, with statistically significant differences (p<0.05) at all of the analyzed intervals (10days p=0.0087, 20days p=0.0012, 30days p<0.0001, 40days p=0.0142). In conclusion, low-level laser therapy stimulated bone regeneration and accelerated the process of integration of autogenous bone grafts.

Multidisciplinary Approach in the Teaching of Dental Sculpture and Anatomy

Universidade de Sao Paulo, Departamento de Ciencias Biologicas, Faculdade de Odontologia de Bauru

Stimulation of morphofunctional repair of the facial nerve with photobiomodulation, using the end-to-side technique or a new heterologous fibrin sealant

This research evaluated the influence of Photobiomodulation Therapy (PBMT) on lesions of the facial nerve repaired with the end-to-side technique or coaptation with a new heterologous fibrin sealant. Thirty-two Wistar rats were separated into 5 groups: Control group (CG), where the buccal branch of the facial nerve was collected; Experimental Suture Group (ESG) and Experimental Fibrin Group (EFG), in which the buccal branch was end-to-side sutured to the zygomatic branch on the right side of the face or coaptated with fibrin sealant on the left side; Experimental Suture Laser Group (ESLG) and Experimental Fibrin Laser Group (EFLG), in which the same procedures were performed as the ESG and EFG, associated with PBMT (wavelength of 830nm, energy density 6.2J/cm2, power output 30mW, beam area of 0.116cm2, power density 0.26W/cm2, total energy per session 2.16J, cumulative dose of 34.56J). The laser was applied for 24s/site at 3 points on the skins surface, for a total application time of 72s, performed immediately after surgery and 3 times a week for 5weeks. A statistically significant difference was observed in the fiber nerve area between the EFG and EFLG (57.49±3.13 and 62.52±3.56μm2, respectively). For the area of the axon, fiber diameter, axon diameter, myelin sheath area and myelin sheath thickness no statistically significant differences were found (p<0.05). The functional recovery of whisker movement occurred faster in the ESLG and EFLG, which were associated with PBMT, with results closer to the CG. Therefore, PBMT accelerated morphological and functional nerve repair in both techniques.

Low-Level Laser Therapy (LLLT) Improves the Repair Process of Peripheral Nerve Injuries: A Mini Review

Purpose: The aim of this study was to perform a mini-review on the effects of low-level laser therapy on nerve regeneration. Methods: In this study, the authors associated the new fibrin sealant derived from snake venom as a method of nerve repair end-to-side. Results and conclusion: The use of fibrin sealant effectively provided an axonal regeneration and the association with low-level laser therapy elevated this regenerative process, as demonstrated in the morphometric and morphological analyzes.

Ozone Therapy in Dentistry: A Systematic Review

El objetivo de esta revision sistematica fue verificar la literatura disponible relacionada a la efectividad y efectos biologicos de la ozonoterapia en periodoncia, ortodoncia e implantes dentales. Se realizo una revision sistematica en septiembre del 2012 en las bases de datos PubMed, LILACS and SciELO por medio de la combinacion de las palabras clave dental implants, periodontics, orthodontics, therapeutics. Se evaluaron los articulos publicados entre los anos 2002 y 2012. Fueron incluidos estudios In vitro e in vivo y publicaciones en Ingles y Espanol, excluyendo posters, carta al editor y conferencias. Estudios in vitro e in vivo mostraron inactivacion de los principales patogenos periodontais con el uso del ozono. Hubo resultados contradictorios y falta de evidencia sobre la accion del ozono en la adhesion de los brackets ortodonticos, asi como tambien en la osteointegracion de los implantes dentales. El ozono puede ser considerado como una terapia alternativa promisoria en la Odontologia. Sin embargo, es necesaria la realizacion de estudios bien disenados para, de ese modo, evaluar la aplicacion del ozono y su efectividad clinica en el campo de la Odontologia.

Bovine bone matrix action associated with morphogenetic protein in bone defects in rats submitted to alcoholism

El abuso prolongado del alcohol produce alteraciones en el tejido oseo, interfiriendo en el proceso de la osteogenesis. El estudio tiene como objetivo evaluar si la matriz osea bovina desmineralizada (Gen-ox®) asociada a la proteina morfogenetica osea (Gen-pro®) altera la neoformacion osea en ratones sometidos a alcoholismo experimental. Fueron utilizados 40 ratones machos (Rattus norvegicus), separados en dos grupos de 20 animales cada uno: Grupo E1, que recibio alcohol etilico a 25% con cavidad quirurgica rellenada solamente por coagulo sanguineo, y Grupo E2, que recibio solo alcohol etilico a 25% con cavidad quirurgica rellenada con hueso bovino desmineralizado cortical asociado a proteina morfogenetica osea. Despues de 3 semanas de adaptacion gradual al alcohol, los animales continuaron recibiendolo en concentracion de 25% por 90 dias, cuando fue realizada la cavidad quirurgica. Luego de la cirugia, los animales continuaron la ingestion alcoholica hasta los periodos de sacrificio de 10, 20, 40 y 60 dias, cuando las tibias fueron removidas para su procesamiento histologico. Los resultados mostraron que en el Grupo E1 hubo reparacion de la cavidad quirurgica y reorganizacion de la medula osea en un menor lapso temporal que en el Grupo E2. En el periodo final del experimento, se observo en los animales del Grupo E2 la presencia de trabeculas oseas espesas alrededor de las particulas de material implantado y pequena area de tejido conjuntivo en la region superficial. Se puede concluir en que el material implantado no acelero el proceso de neoformacion osea, sirviendo como estructura de base para generar osteogenesis.

Inside-out and standard vein grafts associated with platelet-rich plasma (PRP) in sciatic nerve repair. A histomorphometric study

Purpose: To evaluated the tubulization technique with standard and inside-out vein, filled or not with platelet-rich plasma (PRP), in sciatic nerve repair. Methods: Seventy male Wistar rats were randomly divided into five groups: IOVNF (Inside-Out Vein with No Filling); IOVPRP (Inside-Out Vein filled with PRP); SVNF (Standard Vein with No Filling); SVPRP (Standard Vein filled with PRP); Sham (Control). The left external jugular vein was used as graft in a 10 mm nervous gap. Results: In the morphological analysis of all groups, myelinated nerve fibers with evident myelin sheath, neoformation of the epineurium and perineurium, organization of intraneural fascicles and blood vessels were observed. In the morphometry of the distal stump fibers, SVPRP group had the highest means regarding fiber diameter (3.63±0.42 μm), axon diameter (2.37±0.31 μm) and myelin sheath area (11.70±0.84 μm2). IOVPRP group had the highest means regarding axon area (4.39±1.16 μm2) and myelin sheath thickness (0.80±0.19 μm). As for values of the fiber area, IOVNF group shows highest means (15.54±0.67 μm2), but are still lower than the values of the Sham group. Conclusion: The graft filled with platelet-rich plasma, with use standard (SVPRP) or inside-out vein (IOVPRP), promoted the improvement in axonal regeneration on sciatic nerve injury.

Identification of the bony canal of the posterior superior alveolar nerve and artery in the maxillary sinus: tomographic, radiographic, and macroscopic analyses.

The aim of this study was to identify the shape and route of the bony canal of the posterior superior alveolar artery (PSAA) and posterior superior alveolar nerve (PSAN) using different identification methods, including computed tomography (CT), panoramic radiograph, and macroscopic evaluation (corpse and dry skull). Twenty-four patients were analyzed by CT and panoramic and posterior anterior (PA) radiographs; additionally, 90 dry skulls and 21 dissected anatomical specimens were examined. Three-dimensional-CT revealed that the lateral wall of the maxillary sinus resembled a tunnel format in 60% of the treated patients. Out of all 24 patients, the panoramic radiograph identified the bony canal in only one patient; whereas the PA radiograph identified it in 80% of the patients. The dry skulls showed tunnellike routes of the PSAA and PSAN in 65% of the cases. Moreover, the pathway was also visibly observed in the dissected anatomical specimens as a straight shape in 85% of the cases. Thus, our results demonstrated that the most common shape of the bony canal of the PSAA and PSAN is the tunnel format with a straight route by 3D-CT, posterior anterior radiography, and macroscopic evaluation. However, in the panoramic radiographs, it was difficult to identify this canal.

The action of demineralized bovine bone matrix on bone neoformation in rats submitted to experimental alcoholism

The objective of this study was to evaluate whether demineralized bovine bone (Gen-ox®) alters bone neoformation in rats submitted to alcoholism. Forty male rats were separated into two groups of 20 rats and distributed as follows: Group E1, which received 25% ethanol and a surgical cavity filled only by a blood clot, and Group E2, which received 25% ethanol and a surgical cavity filled with Gen-ox®. The animals were euthanized at 10, 20, 40 and 60 days after surgery and necropsy was performed. The histomorphological and histometric analyses of the area of connective tissue and bone neoformation showed that the reorganization of the bone marrow and full repair of the surgical cavity in Group E1 occurred more quickly than in Group E2. It was also noted that in the final period the animals in Group E2 showed areas of connective tissue and thick bone trabeculae around the particles of the implant. It can be concluded that the use of Gen-ox® delayed the process of bone repair in alcoholic rats, although it can be used as filling material because it shows osteoconductive activity, as evidenced by bone tissue formation around the graft particles.