Regeneração óssea guiada para aumento horizontal de rebordo utilizando fibrina rica em plaquetas associada a enxertos ósseos: revisão de literatura / Guided bone regenerationfor horizontal bone augmentation using platelet- rich fibrin associated with bone grafts: literature review

Objetivo: revisar a literatura sobre os diferentes tipos de derivados de plaquetas autólogas e o desempenho clínico do uso do sticky bone para aumento ósseo horizontal de rebordo. Materiais e métodos: Para realização dessa revisão foram realizadas buscas nas bases de dados PubMed, Google Scholar e Web of Science, utilizando os seguintes descritores: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". Foram incluídos artigos publicados em inglês, que abordavam conceitos relacionados aos agregados plaquetários e a regeneração óssea guiada para aumento ósseo horizontal de rebordo utilizando fibrina rica em plaquetas associada à enxertos ósseos (sticky bone). Resultados: Após avaliação dos estudos encontrados foram selecionados 11 artigos sobre o uso do sticky bone para aumento horizontal de rebordo. Para compor este trabalho foram selecionados também 14 estudos de revisão e artigos associados ao tema. Por ser de fácil aplicação e obtenção, muitos autores têm estudado as aplicações cirúrgicas do sticky bone e os resultados demonstram que o aumento horizontal do rebordo utilizando essa técnica pode ser realizado de forma previsível. Conclusão: apesar de haver estudos promissores sobre o uso do sticky bone, falta evidência na literatura sobre seu sucesso clínico. Assim, para compreender o potencial regenerativo desta técnica são necessários um maior número de estudos randomizados, com diferentes materiais de enxerto e protocolos padronizados de obtenção do sticky bone.(AU)

Objective: to review the literature on the different types of autologous platelet derivatives and the clinical performance of using sticky bone for horizontal bone ridge augmentation. Materials and methods: In order to conduct this review, it was conducted searches in the PubMed, Google Scholar, and Web of Science databases using the following descriptors: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". It included articles published in English that addressed concepts related to platelet aggregates and guided bone regeneration for horizontal bone augmentation using platelet-rich fibrin associated with bone grafts (sticky bone). Results: After evaluating the studies found, were selected 11 articles on the use of sticky bone for horizontal ridge augmentation. To compose this work, 14 review studies and articles associated with the topic were also selected. Due to its ease of application and availability, many authors have explored the surgical applications of sticky bone, and the results indicate that horizontal ridge augmentation using this technique can be predictably performed. Conclusion: while there are promising studies on the use of sticky bone, the literature lacks evidence regarding its clinical success. Therefore, to fully understand the regenerative potential of this technique, further randomized studies are needed, involving different graft materials and standardized protocols for obtaining sticky bone.(AU)

Clinical management of endo-perio lesion through guided tissue regeneration: a 5 year follow-Up / Manejo clínico de una lesión endo-perio a través de la regeneración tisular guiada: control post-operatorio de 5 años

ABSTRACT: Progressive periodontal disease causes loss of supporting structures of teeth resulting in deep bony defects. In this case a report of 22-year old female patient is being presented with clinical findings of vertical bone loss in two adjacent teeth, on distal surface of 2nd upper right premolar and mesial surface of upper right 1st molar. Root canal treatment, non-surgical periodontal therapy followed by guided tissue regeneration was carried out using decalcified freeze-dried bone allograft (DFDBA) and collagen membrane. Analysis of clinical and radiographic findings showed marked reduction in pocket depth up to 12mm with hard tissue repair on 3-month, 2-year and 5- year follow ups.

RESUMEN: La enfermedad periodontal progresiva provoca la pérdida de las estructuras de soporte de los dientes, lo que resulta en defectos óseos profundos. En este caso clínico se presenta un informe de una paciente de 22 años con pérdida ósea vertical en la superficie distal del segundo premolar superior derecho y en la superficie mesial del primer molar superior derecho. El tratamiento del conducto radicular, la terapia periodontal no quirúrgica seguida de la regeneración tisular guiada se llevó a cabo utilizando aloinjerto óseo liofilizado descalcificado (DFDBA) y membrana de colágeno. El análisis de los hallazgos clínicos y radiográficos mostró una marcada reducción en la profundidad de la bolsa de hasta 12 mm con reparación de tejido duro en seguimientos de 3 meses, 2 años y 5 años.

La técnica del cono de helado, una posibilidad de tratamiento predecible / The ice cream cone technique, a predictable treatment possibility

ABSTRACT Introduction: The volumetric preservation of bone and soft tissue after a tooth extraction has special relevance in the esthetic zone when it will be rehabilitated by a dental implant. Objective: Describe the prosthodontics treatment in a socket with advanced buccal bone resorption, with a flapless technique for guided bone regeneration and with a dental implant and implant-supported single fixed prosthesis. Case presentation: A case is presented of a male 62-year-old partially dentate patient. Radiographic examination showed the presence of advanced buccal bone resorption in relation to the maxillary left lateral incisor. It was a result of the root displacement secondary to root fracture. In a first surgical phase the lateral incisor was extracted using an atraumatic periotome technique. Particulate cortical bone allograft was compacted into the site to fill the space that was previously occupied by the root of the tooth. Temporary restoration was performed using the extracted natural tooth, which was adhesively bonded to the adjacent teeth. Four months after grafting the extraction site showed an adequate height and width of the bone. In a second surgical phase, an implant was placed. Six months after implant placement, osseointegration was clinically confirmed and a provisional crown was screwed on the implant performed. The final restoration with a zirconium dioxide abutment and a full ceramic crown was obtained and cemented. Conclusions: Regeneration of the buccal plate was possible through the use of particulate cortical bone allograft and a resorbable collagen membrane adapted to the bone defect and placed in a position to recreate the buccal plate. This allowed the installation of an implant 4 months later, the procedure allowing esthetic and functional results using a single fixed prosthesis(AU)

RESUMEN Introducción: La preservación volumétrica de los huesos y tejidos blandos después de una extracción dental tiene especial relevancia en la zona estética cuando será rehabilitada por un implante dental. Objetivo: Describir el tratamiento de prótesis en una cavidad con reabsorción ósea bucal avanzada, con una técnica sin colgajo para la regeneración ósea guiada y con un implante dental y una prótesis fija única con soporte de implante. Presentación del caso: Paciente masculino de 62 años, edente parcial. El examen radiográfico mostró la presencia de reabsorción ósea bucal avanzada en relación con el incisivo lateral superior izquierdo. Fue el resultado del desplazamiento de la raíz secundario a la fractura de esta. En una primera fase quirúrgica, el incisivo lateral se extrajo utilizando una técnica de periotoma atraumático. El aloinjerto de hueso cortical particulado se compactó en el sitio para llenar el espacio que anteriormente ocupaba la raíz del diente. La restauración temporal se realizó utilizando el diente natural extraído, que se unió adhesivamente a los dientes adyacentes. Cuatro meses después del injerto, el sitio de extracción mostró una altura y anchura adecuadas del hueso. En una segunda fase quirúrgica, se colocó un implante. Seis meses después de la colocación del implante, se confirmó clínicamente la osteointegración y se realizó una corona provisional atornillada al implante. La restauración final con un pilar de dióxido de circonio y una corona de cerámica completa se obtuvo y se cementó. Conclusiones: La regeneración de la placa bucal fue posible mediante el uso de aloinjerto de hueso cortical particulado y una membrana de colágeno reabsorbible adaptada al defecto óseo y colocada en una posición para recrear la placa bucal. Esto permitió la instalación de un implante 4 meses después. El procedimiento permitió la estética y los resultados funcionales utilizando una única prótesis fija(AU)

Effect of stem cells combined with a polymer/ceramic membrane on osteoporotic bone repair

Abstract Cell therapy associated with guided bone regeneration (GBR) can be used to treat bone defects under challenging conditions such as osteoporosis. This study aimed to evaluate the effect of mesenchymal stem cells (MSCs) in combination with a poly(vinylidene-trifluoroethylene)/barium titanate (PVDF-TrFE/BT) membrane on bone repair in osteoporotic rats. Osteoporosis was induced in female rats by bilateral removal of the ovaries (OVX) or sham surgery (SHAM), and the osteoporotic condition was characterized after 5 months by microtomographic and morphometric analyses. Calvarial defects were created in osteoporotic rats that immediately received the PVDF-TrFE/BT membrane. After 2 weeks, bone marrow-derived MSCs from healthy rats, characterized by the expression of surface markers using flow cytometry, or phosphate-buffered saline (PBS) (Control) were injected into the defects and bone formation was evaluated 4 weeks post-injection by microtomographic, morphometric, and histological analyses. A reduction in the amount of bone tissue in the femurs of OVX compared with SHAM rats confirmed the osteoporotic condition of the experimental model. More bone formation was observed when the defects were injected with MSCs compared to that with PBS. The modification that we are proposing in this study for the classical GBR approach where cells are locally injected after a membrane implantation may be a promising therapeutic strategy to increase bone formation under osteoporotic condition.

Sugarcane biopolymer as a guide tube in the regeneration of peripheral nerves in rats / Biopolímero de caña de azúcar como tubo guía en la regeneración de nervios periféricos en ratones

SUMMARY: Peripheral nerve regeneration is a serious clinical problem. The goal of this work was to evaluate comparatively a biopolymer tube of sugarcane with an expanded polyethylene tube as a tube guide in peripheral nerve regeneration. Fourteen male albino Wistar rats were used, separated into three different groups: control (CG), lesion + polyethylene tube (PG) and lesion + sugarcane biopolymer (SBG). At 60 days old, animals from the PG and SBG underwent surgery for tubulization of the sciatic nerve, and 60 days after the injury they were sacrificed for collection of the nerve. In the analysis of the number of nerve fibers, a smaller number was seen in the PG and SBG groups compared to the CG, no difference was seen between the PG and SBG groups (p<0.05). With regard to the number of blood vessels, the SBG group had a larger number than the CG and PG groups (p<0.05). The SBG also presented increase on axonal diameter and G -ratio compared to PG (p<0.05). Taken together these data revealed that biopolymer tube favors a suitable environment for peripheral nerve regeneration.

RESUMEN: La regeneración nerviosa periférica es un problema clínico grave. El objetivo de este trabajo fue evaluar comparativamente un tubo de biopolímero de caña de azúcar con un tubo de polietileno expandido, como guía de tubo en la regeneración de nervios periféricos. Se utilizaron dieciocho ratas Wistar albinas macho, separadas en tres grupos: control (CG), lesión + tubo de polietileno (PG) y lesión + biopolímero de caña de azúcar (SBG). A los 60 días de edad, los animales del PG y SBG fueron sometidos a una cirugía para la tubulización del nervio ciático, y 60 días después de la lesión fueron sacrificados para la recolección del nervio. En el análisis del número de fibras nerviosas, se observó un número menor en los grupos PG y SBG en comparación con el CG; no se observaron diferencias entre los grupos PG y SBG (p <0,05). Con respecto al número de vasos sanguíneos, el grupo SBG tuvo un número mayor que los grupos CG y PG (p <0,05). El SBG también presentó un aumento en el diámetro axonal y la proporción G en comparación con PG (p <0,05). En conjunto, estos datos revelaron que el tubo de biopolímero favorece un entorno adecuado para la regeneración de nervios periféricos.

Comparing osteogenic effects between concentrated growth factors and the acellular dermal matrix

Abstract Concentrated growth factor (CGF) is an autogenuous product that contains highly concentrated number of platelets and can be derived from venous blood by selective centrifugation. It has been speculated that local growth factors in human platelets (insulinlike growth factor, IGF; transforming growth factor, TGF-b; platelet derived growth factor, PDGF) would enhance healing of grafts and also counteract resorption. The osteogensis effect of CGF and acellular dermal matrix (ADM) for alveolar cleft defects was evaluated in this study. Twenty alveolar cleft patients were divided randomly into two groups. One group underwent guided bone regeneration (GBR) using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting combined with CGF (CGF group). Cone beam computed tomography (CBCT) images were obtained at 1 week and 6 months following the procedure. Using Mimics 17.0 software, the bone resorption rate and bone density improvement rate were calculated and compared between the two groups. Although not significant between ADM and CGF in bone resorption rate, the bone density improvement in cases with CGF(61.62 ± 4.728%) was much better than in cases with ADM (27.05 ± 5.607%) (p = 0.0002). Thus, CGF could be recommended to patients with alveolar cleft as a better choice.

A comparison of different bone graft materials in peri-implant guided bone regeneration

Abstract The aim of this study was to compare the effects of hydroxyapatite (HA), deproteinized bovine bone (DPB), human-derived allogenic bone (HALG), and calcium sulfate (CAP) graft biomaterials used with titanium barriers for bone augmentation to treat peri-implant defects in rat calvarium treated by guided bone regeneration (GBR). Thirty-two female Sprague-Dawley rats were divided into four groups: DPB, HALG, HA, and CAP. One titanium barrier was fixed to each rat's calvarium after the titanium implants had been fixed. In total, 32 titanium implants and barriers were used. Ninety days after the surgical procedure, all the barriers were removed. After decalcification of bone tissue, the titanium implants were removed gently, and new bone regeneration in the peri-implant area was analyzed histologically. Immunohistochemical staining of vascular endothelial growth factor (VEGF) was also performed. There were no statistically significant between-group differences in new bone regeneration or VEGF expression after 3 months. According to the results of the histological and immunohistochemical analyses, none of the grafts used in this study showed superiority with respect to new bone formation.

Evaluation of photobiomodulation therapy associated with guided bone regeneration in critical size defects. In vivo study

Abstract The repair of bone defects raises the interest of investigators in several health specialties. Grafting techniques with bone substitutes and laser therapies have been investigated to replace autogenous bone and accelerate the bone healing process. Objective To evaluate the effect of photobiomodulation therapy (PBMT) associated with guided bone regeneration (GBR) in critical size defects. Material and Methods The study was conducted on 80 male rats (Rattus norvegicus albinus, Wistar) submitted to surgical creation of a critical size defect on the calvaria, divided into eight study groups: group C (control - only blood clot); group M (collagen membrane); group PBMT (photobiomodulation therapy); group AB (autogenous bone); group AB+PBMT; group AB+M; group PBMT+M; group AB+PBMT+M. The animals were killed 30 days postoperatively. After tissue processing, bone regeneration was evaluated by histomorphometric analysis and statistical analyses were performed (Tukey test, p<0.05). Results All groups had greater area of newly formed bone compared to group C (9.96±4.49%). The group PBMT+M (achieved the greater quantity of new bone (64.09±7.62%), followed by groups PBMT (47.67±8.66%), M (47.43±15.73%), AB+PBMT (39.15±16.72%) and AB+PBMT+M (35.82±7.68%). After group C, the groups AB (25.10±16.59%) and AB+M (22.72±13.83%) had the smallest quantities of newly formed bone. The area of remaining particles did not have statistically significant difference between groups AB+M (14.93±8.92%) and AB+PBMT+M (14.76±6.58%). Conclusion The PBMT utilization may be effective for bone repair, when associated with bone regeneration techniques.

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

Abstract 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.

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

Abstract 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

Evaluación in vitro de la adhesión de células troncales mesenquimales a matrices dentales impresas en tercera dimensión / In vitro Evaluation of the Mesenchymal Stem Cell Adhesion to 3D-Printed Dental Matrices

Antecedentes: En ingeniería de tejidos es fundamental estudiar el sinergismo entre las células troncales mesenquimales y el biomaterial para tener un mayor control sobre los biomiméticos. De esto depende el éxito de tratamientos de lesiones de tamaño crítico.Objetivo: Evaluar la adhesión celular in vitro de células troncales de la pulpa dental humana (CTPD) en matrices impresas con ácido poliláctico {API.).Métodos: Se utilizaron muestras de CTPD criopreservadas y expandidas, cultivadas sobre 24 matrices dentales impresas en 3D con APL, y que se analizaron los días 1, 7 y 15. Se evaluó la fenotipificacion de la CTPD por citometría de flujo y la adhesión celular a la matriz por medio de microscopio electrónico de barrido (SEM). Los datos se agruparon en porcentajes, tanto para el marcador analizado como para la cantidad de células adheridas. Resultados: Las CTPD expresaron positivamente anticuerpos CD73 y CD90 en casi un 100 % y CD 105 en un 56,7 %. Asimismo, expresaron negativamente anticuerpos CD34 y CD45 en más del 98 %. Se observó en SEM que a los 15 días el 99,88 % de las CTPD presentó forma fusiforme o estrellada, lo que significa que estas células se adhirieron a la matriz de APP.Conclusión : El APL no es citotóxico para las CTPD por su composición y características biocompatibles, lo que hizo posible que las células se adhirieran y proliferaran sobre la matriz dental impresa en 3D. Este fue un método in vitro efectivo para emplear en futuros estudios de regeneración de tejidos en odontología.

Background: In tissue engineering it is quite important to study the synergy between mesenchymal stem cells and biomaterials to better control the biomimetic elements. Success in the treatment of critical-size lesions depends strongly on this fact. Objective: To evaluate the in vitro human Dental Pulpal Stem Cell (DPSC) adhesion in printed matrices developed with polylactic acid (PLA). Methods'. Cryopreserved and enlarged DPSC samples were used in the culture of 24 dental 3D-printed matrices developed with PLA that were analyzed on days 1, 7 and 15. The DPSC typification was analyzed with flow cytometry and the cell adhesion to the matrix was analyzed under the scanning electron microscope (SEM). Data were gathered as percentages for both the analyzed marker and the amounts of adhered cells. Results: DPSCs expressed positively the CD73 and CD90 antibodies in almost 100%and the CD 105 in 56.7%. Likewise, DPSCs expressed negatively the CD34 and CD45 in more than 98%. After 15 days it was observed in the SEM that 99.88% of the DPSCs had either a star-like or fusiform shape, which means that they adhered successfully to the PLA matrix. Conclusion: The PLA is not cytotoxic on the DPSCs thanks to its composition and biocompatible features, which allowed the cell adhesion and proliferation in the 3D-printed dental matrix. This in vitro method was effective and should be use in future studies on tissue regeneration in dentistry.

Regeneración tisular guiada en defecto óseo de 3 paredes: enfermedad periodontal y oclusión / Guided tissue regeneration and in a three-walled osseous defect: periodontal disease and occlusion

Relacionar la importancia del éxito en regeneración tisular guiada y el correcto diagnóstico del problema, en este caso enfermedad periodontaly un contacto prematuro en ORC producto de una obturación de amalgama incorrecta. Caso clínico: tratamiento de un defecto infraóseo de3 paredes mediante la utilización de hueso de origen bovino particulado junto con proteínas derivadas de la matriz del esmalte. Tanto los parámetros clínicoscomo los radiográficos fueron evaluados al inicio, en el postquirúrgico inmediato y a los 12 meses. Conclusión: se observó un alto grado de regeneración pasados los 12 meses del tratamiento. Parecería no ser siempre necesaria la utilización de membrana colágena. Las proteínas derivadas de la matrizdel esmalte serían un sustituto de la membrana en algunos casos. Resulta fundamental el chequeo de la situación oclusal en piezas periodontalmente comprometidas...

Tissue characterization following revascularization of immature dog teeth using different disinfection pastes

Abstract Revascularization of immature teeth with necrotic pulps traditionally involves the use of triple antibiotic paste, which may sometimes lead to undesirable complications. The objective of this study was to assess tissue repair in immature dog teeth with apical periodontitis subjected to revascularization, comparing two different pastes used for root canal disinfection. Apical periodontitis was induced in 30 dog premolars. Teeth were randomly divided into three experimental groups: root canals filled with triple antibiotic paste (n = 10); root canals filled with 1% propolis paste (n = 10); and no medication (n = 10). An additional group (n = 10, no intervention) was used as control. After 7 months, the jaws were histologically evaluated for the following variables: newly formed mineralized tissue (present/absent); vital tissue in the canal space (absent/periodontal ligament-like/pulp-like); apical extension of root (present/absent); and severity of inflammatory process (absent/mild/moderate/severe). There were no statistically significant differences among the experimental groups in new mineralized tissue formation and apical root development. The formation of vital tissue in the canal space, in turn, was statistically different between the triple paste and propolis groups: vital tissues were present in all revascularized teeth disinfected with propolis paste (100%), compared to 71% of those disinfected with the triple paste. Severity of inflammatory process was different between the triple paste and no medication groups. The new tissues formed onto canal walls and in the root canal space showed characteristics of cementum and periodontal ligament, respectively. Propolis may have some advantages over the triple paste for the revascularization of immature teeth.

Immunohistochemical expression of TGF-ß1 and osteonectin in engineered and Ca(OH)2-repaired human pulp tissues

Abstract The aim of the present study was to evaluate the expression of transforming growth factor-β1 (TGF-β1) and osteonectin (ON) in pulp-like tissues developed by tissue engineering and to compare it with the expression of these proteins in pulps treated with Ca(OH)2 therapy. Tooth slices were obtained from non-carious human third molars under sterile procedures. The residual periodontal and pulp soft tissues were removed. Empty pulp spaces of the tooth slice were filled with sodium chloride particles (250-425 µm). PLLA solubilized in 5% chloroform was applied over the salt particles. The tooth slice/scaffold (TS/S) set was stored overnight and then rinsed thoroughly to wash out the salt. Scaffolds were previously sterilized with ethanol (100-70°) and washed with phosphate-buffered saline (PBS). TS/S was treated with 10% EDTA and seeded with dental pulp stem cells (DPSC). Then, TS/S was implanted into the dorsum of immunodeficient mice for 28 days. Human third molars previously treated with Ca(OH)2 for 90 days were also evaluated. Samples were prepared and submitted to histological and immunohistochemical (with anti-TGF-β1, 1:100 and anti-ON, 1:350) analyses. After 28 days, TS/S showed morphological characteristics similar to those observed in dental pulp treated with Ca(OH)2. Ca(OH)2-treated pulps showed the usual repaired pulp characteristics. In TS/S, newly formed tissues and pre-dentin was colored, which elucidated the expression of TGF-β1 and ON. Immunohistochemistry staining of Ca(OH)2-treated pulps showed the same expression patterns. The extracellular matrix displayed a fibrillar pattern under both conditions. Regenerative events in the pulp seem to follow a similar pattern of TGF-β1 and ON expression as the repair processes.

Avaliação da cicatrização de defeitos ósseos criados cirurgicamente em calvárias de ratos tratados com regeneração óssea guiada e enxertos de origem bovina associados ou não ao laser de baixa intensidade: estudo histológico e histométrico / Evaluation of the bone healing in critical-size calvarial defects in rats treated with guided bone regeneration and inorganic bovine bone associated or not with low level laser: histological and histometric study

O propósito deste estudo foi avaliar histologicamente o papel do laser de baixa intensidade (LB) no processo de cicatrização óssea de defeitos de tamanho crítico em calvárias de ratos tratados com osso bovino (BO) associados a regeneração óssea guiada (ROG). Foram utilizados 80 ratos machos adultos (Rattus norvegicus, albinus, Wistar), pesando entre 250 e 300 g. Um defeito ósseo de tamanho crítico (DTC) com 5 mm de diâmetro foi criado na calvária de cada animal. Os animais foram divididos aleatoriamente em 8 grupos de tratamento (n=10), sendo: 1) Grupo C (controle), 2) Grupo LB - laser de baixa intensidade (laser de baixa intensidade - GaAlAs, 730nm, 100mW, 6J, 210J/cm2), 3) Grupo BO (osso bovino), 4) Grupo ROG (membrana colágena), 5) Grupo BO/ROG (osso bovino/membrana colágena), 6) Grupo BO/LB (osso bovino/laser de baixa intensidade), 7) Grupo ROG/LB (membrana colágena/laser de baixa intensidade), 8) Grupo BO/ROG/LB (osso bovino/laser de baixa intensidade/membrana colágena). Após 30 dias, os animais foram submetidos à eutanásia. As variáveis avaliadas foram: área de osso neoformado (AON), extensão linear de osso (ELO) e área de partículas remanescentes (APR). Foi utilizado o teste paramétrico ANOVA, seguido pelo teste de Tukey. Todos os grupos apresentaram maiores médias de AON em relação ao grupo C, exceto os grupos BO, BO/ROG e BO/ROG/LB. Todos os grupos apresentaram médias de ELO estatisticamente diferente do grupo C, exceto o BO. O grupo BO/ROG/LB não apresentou maiores médias de AON e ELO que o Grupo BO/ROG, entretanto mostrou maior formação óssea na região da membrana quando utilizado o LB em associação ao BO/ROG na análise histológica. Maior APR foi observada nos grupos em que BO não foi irradiado pelo LB. Entretanto, não ocorreu diferença estatisticamente significativa entre APR nos grupos BO e BO/ROG, BO/LB e BO/ROG/LB, BO/ROG e BO/ROG/LB. O LB não levou a maior formação óssea histométrica quando associado ao BO/ROG, apesar de...

The purpose of this study was to evaluate histologically the low level laser (LB) on bone healing in critical-size calvarial defects (CSD) in rats treated with inorganic bovine bone (BO) and guided bone regeneration (GBR). Were used 80 male adult rats (Rattus norvegicus albinus Wistar) weighing 250 to 300 g. A bone defect of critical size (DTC) with 5 mm in diameter was created in the calvaria of each animal. The animals were randomly divided into 8 treatment groups (n = 10), 1) Group C (control), 2) Group LB - low level laser (low level laser - GaAlAs, 730nm, 100mW, 6J, 210J / cm2 ), 3) Group BO (bovine bone), 4) Group ROG (collagen membrane), 5) Group BO / ROG (bovine bone / collagen membrane), 6) Group BO/ LB (bovine bone / low level laser), 7) Group ROG / LB (collagen membrane / low level laser), 8) Group BO / LB / ROG (bovine bone /low level laser / collagen membrane). After 30 days, the animals were euthanized. The variables analyzed were newly formed bone area (AON), linear extension of bone (ELO) and area of remnant particles (APR). The parametric test ANOVA followed by Tukey's test was used. All groups have the highest mean AON compared to C group except the group BO, BO/ROG and BO / ROG / LB. All groups showed mean of ELO statistically different from group C, except the BO. The Group BO/ROG/LB did not show higher ELO and AON than Group BO/ROG, however showed increased bone formation in the membrane area when used LB with BO/ROG in the histological analysis. Higher APR was observed in the groups where BO is not irradiated by LB. However, there was no significant difference between APR in BO BO and BO/ROG groups, BO/LB and BO/ROG/LB groups. The LB has not provide greater histometric bone formation when combined with BO / ROG, despite promote greater bone formation in the histological analysis...

Comparing open wound measuring methods popularly used in experimental studies / Estudo comparativo de métodos de avaliação de contração de feridas cutâneas abertas

Tissue repair is a response reaction to lesions and aggressions that constitutes a dynamic process to maintain the integrity of the organism. Wound healing experiments have used several approaches in order to assess and compare treatment methods, and these discrepancies hamper comparisons among assays. This study assessed three different methods of wound measurement commonly used in healing assays: clock method, graph paper method, and computer-assisted image analysis. We used 30 Wistar rats, kept in appropriate conditions for animal well-being. After anesthesia, and using an eight-millimeter punch, two lesions were made in the back region of each rat. The wounds were assessed on days four, seven, and 14 after infliction. At four days, all methods generated similar results. By day seven, the clock method had lost precision, likely due to wound shrinkage, and yielded greater means compared to the other two methods. On the last assessment, the computer-assisted method appeared to have more precise results, with the other two generating statistically higher means. Computer-assisted image analysis seems to have maintained wound measuring precision throughout this experiment, even when faced with small lesions. Considering these results, the authors recommend the use of computer-assisted measurements in future experiments.

O reparo tecidual surge em resposta às lesões e constitui-se de um processo dinâmico para manutenção da integridade do organismo. Nos estudos sobre cicatrização de feridas, tem se utilizado várias técnicas buscando-se uma avaliação da eficácia de meios de tratamento local. Sendo assim, o presente trabalho objetivou comparar três métodos de avaliação experimental de áreas de feridas, sendo eles: o método do relógio, papel milimetrado e avaliação computadorizada. Para realização do experimento, foram utilizados 30 ratos Wistar em condições de bem-estar. Após realizada a anestesia, foram confeccionadas duas lesões no dorso de cada animal com punch de 8 mm, sendo as feridas avaliadas após quatro, sete e 14 dias de tratamento. Observou-se que aos quatro dias de tratamento, todos os métodos apresentaram o mesmo desempenho, enquanto aos sete e 14 dias, o método do relógio, apresentou maior média de área, perdendo precisão, e aos 14 dias, a avaliação computadorizada apresentou resultados mais precisos em relação a ambos os outros métodos. Concluiu-se que a avaliação computadorizada através de software de áreas de feridas cutâneas apresenta resultados mais precisos em relação aos métodos do relógio e papel milimetrado, principalmente em lesões menores.

Immunolocalization of markers for bone formation during guided bone regeneration in osteopenic rats

Objective The aim of this paper was to evaluate the repair of onlay autogenous bone grafts covered or not covered by an expanded polytetrafluoroethylene (e-PTFE) membrane using immunohistochemistry in rats with induced estrogen deficiency. Material and Methods Eighty female rats were randomly divided into two groups: ovariectomized (OVX) and with a simulation of the surgical procedure (SHAM). Each of these groups was again divided into groups with either placement of an autogenous bone graft alone (BG) or an autogenous bone graft associated with an e-PTFE membrane (BGM). Animals were euthanized on days 0, 7, 21, 45, and 60. The specimens were subjected to immunohistochemistry for bone sialoprotein (BSP), osteonectin (ONC), and osteocalcin (OCC). Results All groups (OVX+BG, OVX+BMG, SHAM+BG, and SHAM+BMG) showed greater bone formation, observed between 7 and 21 days, when BSP and ONC staining were more intense. At the 45-day, the bone graft showed direct bonding to the recipient bed in all specimens. The ONC and OCC showed more expressed in granulation tissue, in the membrane groups, independently of estrogen deficiency. Conclusions The expression of bone forming markers was not negatively influenced by estrogen deficiency. However, the markers could be influenced by the presence of the e-PTFE membrane. .

Bone augmentation with occlusive barriers and cortical particulate allograft in transverse maxillary defects: a pilot study / Aumento óseo con barreras oclusivas y aloinjerto cortical particulado en defectos maxilares transversales: un estudio piloto

The centripetal resorption of maxilla is a continuous process after tooth loss. For treatment of deficient bone sites, autologous bone grafts may be used, as an alternative, biomaterials can be applied which do not require intra or extraoral donor sites. The present report describes the use of occlusive barriers and cortical particulate allograft in transverse maxillary defects. This surgical approach was performed in five patients (4 females and 1 male, aged 20 to 37 years). Clinical results show that sufficient hard tissue was formed to allow implant born rehabilitation in the former insufficient bone sites. Histological evaluation revealed small amounts of newly formed bone with a predominance of collagen fibrous tissue and mature bone with very little cellular elements. Depending on the original site situation, the minimally invasive approach with occlusive barrier and cortical particulate allograft may be applied. We observed a mean of 2.3, 2.7 and 2.9 mm in bone gain for ridge, middle and apical area, respectively.

La reabsorción centrípeta del maxilar es un proceso continuo después de la pérdida dentaria. Para el tratamiento de sitios óseos deficientes, se pueden utilizar injertos de hueso autólogo; como alternativa, se puede aplicar biomateriales, que no requieren sitios donantes intra o extraorales. El presente reporte describe la utilización de barreras oclusivas y aloinjerto cortical particulado en defectos maxilares transversales. Este abordaje quirúrgico fue realizado en cinco pacientes (4 mujeres y 1 hombre, de 20 hasta 37 años de edad). Los resultados clínicos muestran que se formó suficiente tejido duro para permitir la rehabilitación de implantes en los sitios de hueso insuficiente. La evaluación histológica reveló pequeñas cantidades de hueso neoformado con predominantes fibras colágenas y hueso maduro con muy pocos elementos celulares. Dependiendo de la situación del sitio original, se puede aplicar un abordaje mínimamente invasivo con barreras oclusivas y aloinjerto cortical particulado. Se pudo observar un aumento óseo promedio de 2,3, 2,7 y 2,9 mm para las regiones de la cresta ósea, zona media y apical, respectivamente.

Treatment Algorithm of Complications after Filler Injection: Based on Wound Healing Process

Soft tissue filler injection has been a very common procedure worldwide since filler injection was first introduced for soft tissue augmentation. Currently, filler is used in various medical fields with satisfactory results, but the number of complications is increasing due to the increased use of filler. The complications after filler injection can occur at any time after the procedure, early and delayed, and they range from minor to severe. In this review, based on our experience and previously published other articles, we suggest a treatment algorithm to help wound healing and tissue regeneration and generate good aesthetic results with early treatment in response to the side effects of filler. Familiarity with the treatment of these rare complications is essential for achieving the best possible outcome.

Tratamiento de un defecto vertical profundo en un pilar protético mediante la técnica de regeneración tisular guiada: evaluación clínica y radiográfica con reentrada a los 12 meses (AU) / Treatment of a deep vertical intrabony defect in a prosthetic abutment by means of guided tissue regeneration: clinical and radiographic evaluation with re-entry procedure 12 months later

Objetivo: evaluar clínica y radiográficamente el tratamiento de un defecto vertical profundo en un pilar protético mediante la técnica de regeneración tisular guiada (RTG). Caso clínico: se presenta el tratamiento de un defecto vertical profundo mediante una técnica combinada de injerto bovino y membrana de colágeno. Los parámetros clínicos y radiográficos fueron evaluados al incicio y 12 meses después, momento en el cual se realizó una reentrada quirúrgica para evaluar la regeneración obtenida. Conclusión: los resultados clínicos mostraron una mejoría en los parámetros evaluados y radiográficamente, un año después, se observó un alto grado de regeneración. La utilización de esta técnica (RTG) en pilares dentarios estratégicos permite mejorar el pronóstico periodontal de la pieza dentaria y posteriormente, incluirlos en la futura rehabilitación protética. Más allá de las limitaciones de este estudio, los resultados sugieren que la terapia regenerativa combinada es eficaz para el tratamiento de pilares periodontalmente comprometidos.