Rogério Leone 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.

Effect of Low-Intensity Pulsed Ultrasound on Bone Regeneration Biochemical and Radiologic Analyses

The purpose of this study was to evaluate the effects of low‐intensity pulsed ultrasound at 1.0 MHz on the healing process of fractures with bone loss in the rat fibula by alkaline phosphate level measurement and radiologic analyses.

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.

Comparative study between standard and inside-out vein graft techniques on sciatic nerve repair of rats. Muscular and functional analysis

Purpose: To compare the functional result of standart vein grafts and inside-out vein graft technique on sciatic nerve repair. Methods: We used 24 male Wistar rats divided into 4 groups: control group (CG), standard vein graft group (SVG), Inside-out vein graft group (IOVG) and denervated Group (DG). SVG, IOVG and DG underwent total section of the sciatic nerve, SVG and IOVG however underwent nerve repair surgery using a graft with normal jugular vein and inside-out jugular vein, respectively. Histological analysis of the soleus and Extensor Digitorum Longus (EDL), and Sciatic Functional Index were used to compare the results after 6 weeks. Results: Both grafts acted favorably in muscle recovery and improved functionality; They were similar in all parameters, however, in more points SVG achieved similar to the CG, in the other hand IOVG more times was similar to DG. Fact that makes the graft with normal vein the most viable option between the two options. Conclusion: Both types of grafts acted beneficially wherein the graft normal vein has proved to be the best option.

Comparison of results obtained with standard and inside out vein graft techniques and their implication on neurotrophin expression in repair of nerve defect: An experimental study

Standard vein graft (SVG) and inside out vein graft (IOVG) techniques to promote peripheral nerve regeneration have been widely studied since last two decades. In this experimental study, we attempted to compare these two techniques and analyze the differences in the expression of the neurotrophins during peripheral nerve regeneration. Thirty‐six male Wistar rats were used in this sciatic nerve transection model and were divided into two experimental groups (SVG and IOVG) and one sham operated control group. An overall defect of 10 mm was made in the sciatic nerve of the animals in the experimental groups. Each group consisted of two time intervals of 6 and 12 weeks (n = 6). After each experimental interval, sciatic functional index (SFI) along with area and diameter of the axons and fibers of each group were calculated. Muscle mass measurements were also evaluated to see any functional recovery in the groups. Expression of neurotrophins in the graft and distal stump were analyzed with the help of RT‐PCR. SFI obtained from walking track analysis showed poor motor recovery in the experimental groups during both time intervals. No significant differences in the histological, morphometric (P > 0.05), and muscle mass measurements (P > 0.05) between the two experimental groups were observed. Analysis of RT‐PCR data exhibited an increase in the expression of NT‐3 with time in both the grafts (6 weeks 0.428 ± 0.392, 12 weeks 1.089 ± 0.455, P < 0.05) and distal stump (6 weeks 0.411 ± 0.306, 12 weeks 0.807 ± 0.303, P < 0.05) of the SVG group. The study concludes that there is no substantial difference in the nerve regeneration ability between both the techniques. Also, the difference in the level of NT‐3 between SVG and IOVG suggests a distinct regulation of NT‐3 in peripheral nerve regeneration.

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.

Surgical anatomy of the human middle ear: an insight into cochlear implant surgery.

PurposeThis research was designed to aid practical otologic studies of the human middle ear. The topographic anatomy access of the middle ear was described with special focus to the cochlear implant procedure. It was conducted in an attempt to elucidate factors that would ultimately determine the ease of insertion of an electrode array.MethodsFifteen right and 12 left temporal bones were dissected under the surgical microscope. After performing appropriate incisions, the distances between the stapedius muscle tendon, incus long crus and the cochleostomy were measured with the help of a digital microscope (Dino-Lite plus®).ResultsAfter performing statistical analysis, we found that strong relationship exists in the distances between the measured anatomical landmarks.ConclusionMicroscopic anatomical studies of the temporal bone are essential to safely perform surgical intervention within the middle ear. The results shows that morphometric data concerning different anatomical structures inside the middle ear, particularly distances, is an important contribution towards the planning of safe surgical procedures.