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OBJECTIVE: This study aimed to assess the effect of titanium dioxide (TiO2) and silver (Ag) nanoparticles dispersed in glycerol or water, serving as optical clearing agents nanocolloids (OCAs-NC), for improving optical coherence tomography (OCT) images and highlighting incipient lesions in ex vivo human teeth. MATERIALS AND METHODS: Twelve human teeth with incipient lesions were divided into seven groups according to the OCA-NC; they were subjected to G1 (air), G2 (glycerol), G3 (TiO2 0.1%), G4 (TiO2 0.01%), G5 (TiO2 0.001%), G6 (AgNO3 10%), and G7 (AgNO3 100%). The OCA-NC was applied to the occlusal surface, and two-dimensional images of the specimens were analyzed using OCT (930 nm central wavelength; 100 nm bandwidth; 5 mW output power; axial resolution of 7/5.3 µm in water and air, respectively; lateral resolution of 8 µm; and light penetration depth of 1.6 mm inside the sample). RESULTS: The findings demonstrated that the utilization of OCAs-NC containing metallic or dielectric nanoparticles (AgNO3 and TiO2) led to improved differentiation between sound and demineralized enamel on occlusal surfaces. Additionally, it enhanced the depth of image penetration when analyzing this hard tissue with OCT. CLINICAL RELEVANCE: In the current context of minimally invasive dentistry, the use of OCAs-NC in conjunction with OCT can provide clinicians with early diagnosis, allowing for the determination of less/more invasive therapies and consequently halting the disease before cavitation of dental tissues occurs.

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Objective: To carry out a histological and morphometric analysis of the antimicrobial effect of Er:YAG laser irradiation combined with photodynamic therapy (PDT) on root canals infected with Enterococcus faecalis. Background: PDT and Er:YAG laser irradiation may be alternatives for effective endodontic disinfection but there are no data on the combination of these therapies. Materials and methods: Forty single-rooted bovine teeth had their roots contaminated with E. faecalis for 72 h. The teeth were randomly divided into four groups (n = 10): group 1, irrigation with 2.5% sodium hypochlorite (NaOCl); group 2, Er:YAG laser (λ2940 nm, 15 Hz, 100 mJ); group 3, PDT with 0.07% methylene blue as photosensitizer and laser irradiation (λ660 nm, power 40 mW, 5 min); and group 4, Er:YAG laser + PDT. After treatment, the teeth were examined by confocal laser scanning microscopy to verify bacterial viability, and morphometric analysis of the images was performed. Results: The PDT and Er:YAG + PDT treatments promoted the greatest reduction in bacteria among the proposed therapies, whereas 2.5% NaOCl was the least effective in bacterial elimination. A statistically significant difference (p < 0.05) was observed among the groups studied, except between the group combining Er:YAG and PDT and the group treated with PDT alone. Conclusions: PDT combined or not with Er:YAG laser was found to be more effective in root canal disinfection when compared with the other groups.

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Introduction: Since photobiomodulation therapy (PBMT) favors in vitro mesenchymal stem cell (MSC) preconditioning before MSC transplantation, increasing the proliferation of these cells without molecular injuries by conserving their characteristics, in the present in vitro study we analyzed the effect of PBMT on the proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs). Methods: Irradiation with an InGaAIP Laser (660 nm, 10 mW, 2.5 J/cm2 , 0.08 cm2 spot size, and 10 s) was carried out. The cells were divided into four groups: CONTROL [cells grown in Dulbecco's Modified Eagle Medium (DMEM)], OSTEO (cells grown in an osteogenic medium); PBMT (cells grown in DMEM+PBMT), and OSTEO+PBMT (cells grown in an osteogenic medium plus PBMT). The cell proliferation curve was obtained over periods of 24, 48 and 72 hours using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Osteogenic differentiation was analyzed by the formation of calcium nodules over periods of 7, 14 and 21 days. Morphometric analysis was performed to quantify the total area of nodular calcification. Results: The highest cell proliferation and cell differentiation occurred in the OSTEO+PBMT group, followed by the PBMT, OSTEO and CONTROL groups respectively, at the observed times (P <0.05). Conclusion: PBMT enhanced the osteogenic proliferation and the differentiation of hUCMSCs during the periods tested, without causing damage to the cells and preserving their specific characteristics, a fact that may represent an innovative pretreatment in the application of stem cells.

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OBJECTIVE: To evaluate the efficacy of photobiomodulation for bone repair of critical surgical wounds with implants of bone morphogenetic proteins (BMPs) and bovine biological membranes, using histological and histomorphometric analysis. BACKGROUND: Tissue engineering has been developing rapidly through the use of various biomaterials for the treatment of bone defects, such as mechanical barriers consisting of biological membranes and implants of biomaterials for bone supply. MATERIALS AND METHODS: Thirty-two male rats were divided into four groups (n = 8): group I-C: control; group II-PT: photobiomodulation therapy; group III-PM: Gen-Pro® BMPs+Gen-Derm® membrane; and group IV-PMPT: Gen-Pro® BMPs+Gen-Derm® membrane+photobiomodulation therapy. A 3 mm bone cavity was performed in the upper third of the lateral surface of the right rat femur to obtain a bone defect considered to be critical. The irradiated groups received seven applications of AlGaAs diode laser 830 nm, P = 40 mW, continuous wave (CW) emission mode, f ∼ 0.6 mm, 4 J/cm2 per point (north, south, east, and west) at 48 h intervals, for a total of 16 J/cm2 per session (final dose: 112 J/cm2). Bone repair was evaluated at sacrifice 15 and 30 days after the procedure. The specimens were embedded in paraffin and stained with hematoxylin and eosin and Picrosirius for analysis by light microscopy and by the Leica interactive measurement module software. Statistical analysis was performed (p < 0.05%). RESULTS: Histological analysis confirmed the histomorphometric results, with the experimental groups showing bone neoformation of significantly higher quality and quantity at the end of 30 days compared with the control group. CONCLUSIONS: Photobiomodulation therapy was effective for bone repair mainly when associated with BMPs and a biological membrane. The results of this study are promising and stimulate further scientific and clinical research.

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The goal of this work is to investigate the thermal effects of femtosecond laser (fs-laser) ablation for the removal of carious dental tissue. Additional studies identify different tooth tissues through femtosecond laser induced breakdown spectroscopy (fsLIBS) for the development of a feedback loop that could be utilized during ablation in a clinical setting. Scanning Election Microscope (SEM) images reveal that minimal morphological damages are incurred at repetition rates below the carbonization threshold of each tooth tissue. Thermal studies measure the temperature distribution and temperature decay during laser ablation and after laser cessation, and demonstrate that repetition rates at or below 10kHz with a laser fluence of 40 J/cm2 would inflict minimal thermal damage on the surrounding nerve tissues and provide acceptable clinical removal rates. Spectral analysis of the different tooth tissues is also conducted and differences between the visible wavelength fsLIBS spectra are evident, though more robust classification studies are needed for clinical translation. These results have initiated a set of precautionary recommendations that would enable the clinician to utilize femtosecond laser ablation for the removal of carious lesions while ensuring that the solidity and utility of the tooth remain intact.

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INTRODUCTION: For a long time researchers have tried to find out a way to grow tissues back to the human body in order to solve transplantation problems by offering the unique opportunity to have their organs back, working properly, in search of life dignity. LITERATURE REVIEW: Stem cells seem to be present in many other tissues than researchers had once thought; and in some specific sites they can be easily collected, without the need of expensive interventions. The oral cavity is one of these regions where their collection can be accomplished, with plenty of accessible sites enriched with these precious cells. AIM: The aim of this literature review is to research where in the mouth can scientists find stem cells to be used in the near future. KEY-MESSAGE: The aim of this literature review is to research where stem cells can be found and collected in the oral cavity.

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BACKGROUND: Aim of this study was to investigate the influence of gutta-percha and metallic posts on the efficiency of Cone Beam Computed Tomography (CBCT) in diagnosing Vertical Root Fracture (VRF). METHODS: Forty-eight teeth were divided into 3 experimental and 3 control groups. The teeth of the first experimental group and the first control group received neither gutta-percha nor metal posts. The teeth of the second experimental group and the second control group were filled with gutta-percha, and the teeth of the third experimental group and the third control group were filled with the metal posts. The teeth of the experimental groups were artificially fractured. The teeth were evaluated through images taken by a Prexion scanner with a 0.1 mm resolution. Fisher's exact test was used to measure the following values: sensitivity, false negative, specificity, false positive and accuracy for the VRF detection through the scanner. Three observers calibrated and blinded to the protocol evaluated the images. RESULTS: The inter-observer Kappa coefficient was 0.83. The presence of posts and gutta-percha reduced the sensitivity and the accuracy in detecting the VRF. Regarding to the sensitivity (p = 0.837, p = 0.304, p = 0.837 for evaluator 1, 2 and 3, respectively) and specificity (p = 0.162, p = 0.056, p = 0.062 for evaluator 1, 2 and 3, respectively), Fisher's exact test showed no statistically significant difference among the evaluated groups. However, a significant difference was observed in relation to the accuracy in the results of evaluator 2 (p = 0.03), which showed a much lower accuracy for the post group (50 %) than for the Nonfilled group (93.8 %). CONCLUSIONS: The Prexion tomograph was precise in detecting vertical root fractures and the CBCT diagnostic ability was not influenced by the presence of posts or gutta-percha.

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Objective: The aim of this study was to criticaly review the published literature regarding the clinical aspects involved in the rehabilitation of edentulous patients using Branemark protocol and overdenture prostheses.Methods: An active search was conducted in the LILACS, MEDLINE, PubMed, and SciELO databases using the descriptors: "Coating for dentures" (Overlay Prosthesis and Overdenture) and "Implant-supported fixed dental prosthesis" (Protesis dental de suporte implantado, Dental prosthesis, and Implant Supported Prosthesis) in Portuguese, English, and Spanish between January 2000 and October 2014.Results: The following parameters should be considered when selecting between Branemark protocol and overdenture prostheses: bone support, lip support, lip-line, upper lip length, oral mucosa conditions and size, alveolar ridge contour, crown-bone ratio, interarch space, and speaking space. Overdenture rehabilitation can provide many benefits to patients, such as prosthetic retention, stability, comfort, and improved aesthetics.Conclusions: This study highlights the need for a thorough individualized treatment planning to ensure that fixed prostheses and overdentures have an excellent prognosis when used appropriately in suitable patients at the appropriate time.

Objetivo: Verificar por meio de revisão crítica da literatura os aspectos clínicos durante o planejamento de pacientes edêntulos frente à utilização de próteses tipo protocolo de Branemark e overdenture.Métodos: Busca ativa nas bases de dados LILACS, MEDLINE, PubMed e SciELO por meio dos descritores: "Revestimento de dentadura" (Prótese de Recobrimento e Overdenture) e "Prótese dentária fixada por implante" (Protesis dental de suporte implantado e Dental prosthesis, implant supported) entre janeiro de 2000 até outubro de 2014 nas línguas Portuguesa, Inglesa e Espanhola.Resultados: Deve-se levar em consideração para indicar as próteses overdentures e protocolo o suporte ósseo, suporte labial, linha do sorriso, comprimento do lábio superior, qualidade e quantidade da mucosa, contorno do rebordo alveolar, relação coroa/osso, espaço interarcos e zona fonética. A reabilitação com overdenture pode trazer muitos benefícios ao paciente, tais como retenção, estabilidade, conforto, e a estética.Conclusões: Evidencia-se a necessidade de um planejamento individualizado, para que se chegue a um correto plano de tratamento, no qual as próteses fixas e overdentures possam ter um excelente prognóstico, desde que utilizadas no momento apropriado e no paciente indicado.

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The oroantral fistula is one of the complications most common after dental extractions in posterior maxillary, mainly in the region of second and third molar. The diagnosis is based on clinical signs and symptoms, which may be present in pain, fever, hyposmia and drainage of purulent discharge; additional examinations such as computed tomography and sinus nasal endoscopy improve diagnostic precision. It is therefore of paramount importance to correct early diagnosis and treatment avoiding in this way, the symptons of sinusitis, infections and dysphonia. Several surgical techniques have been proposed for the closure of the bucosinusal fistula; the use of Bichat´s fat pad has become a successful alternative among them. Many surgical treatments have been to propose for closure of bucosinusal fistula; Bichat fat pad has been a good alternative. The propose for this article is report two cases with closure of bucosinusal fistulas through Bichat's fat pad, as well as to discuss the surgical techniques, characteristics, indications and peculiarities.

A fístula bucosinusal ou oro-antral é uma das complicações mais comuns, após extrações dentárias na região posterior de maxila, principalmente em região de segundo e terceiro molares permanentes. O diagnóstico se baseia em sinais e sintomas clínicos, nos quais pode-se destacar: dor, febre, hiposmia e drenagem de secreção purulenta. Os exames complementares como a endoscopia sinonasal e a tomografia computadorizada melhoram a precisão diagnóstica. Assim, é de suma importância, o correto diagnóstico e tratamento precoce, evitando dessa maneira a instalação de sinusites, infecções e disfonia. Diversas técnicas cirúrgicas têm sido propostas na literatura, para o fechamento da fístula bucossinusal, dentre elas, a utilização do corpo adiposo de Bichat tem se tornado uma alternativa bem sucedida. O objetivo deste trabalho é relatar dois casos clínicos de fechamento de fístulas bucossinusais através do retalho da bola de Bichat, realizados pelo Departamento de Cirurgia e Traumatologia Bucomaxilofacial do Hospital da Face e Hospital da Restauração em Recife, Pernambuco. Ainda, descrever acerca de sua técnica cirúrgica, características, indicações e peculiaridades.

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Orthognathic surgery is the surgical procedure that makes correcting deformities of the bones in the region of the maxilla and mandible a reality in the Brazilian dentistry. However, this type of surgery usually involves paresthesia in the postoperative period, concerning the surgeons who perform them and generating discomfort to patients. This study aimed at evaluating the effect of infrared laser (830 nm) in the prevention and treatment of paresthesias after orthognathic surgery. Six patients underwent orthognathic surgery: the experimental group composed of 4 patients and the control group that did not receive laser therapy composed of 2 patients. The experimental group received laser applications during the transoperative and 12 postoperative sessions. Tests for mechanical (deep and shallow) and thermal (cold) sensitivity were performed in the preoperative and postoperative period (during 12 sessions) in the lip and chin areas by the same operator. The paresthesia was classified into 1, strong; 2, moderate; 3, mild; and 4, absent, through the patient's response to stimuli. The results showed that all patients had no disturbance of sensitivity in the preoperative period, but paresthesia was presented at various levels in the postoperative period. Both groups showed recovery of deep mechanical sensitivity within a shorter time interval compared with the superficial mechanical and thermal sensitivity. However, at the 12th assessment, patients who underwent the laser therapy showed better reduction in the level of paresthesia or even complete regression of this. The laser, therefore, brought benefits to the treatment of paresthesia, accelerating the return of neurosensorial sensitivity.

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The purpose of this study was to address the following question: among patients with acute or chronic temporomandibular disorders (TMD), does low-level laser therapy (LLLT) reduce pain intensity and improve maximal mouth opening? The sample comprised myogenic TMD patients (according Research Diagnostic Criteria for TMD). Inclusion criteria were: male/female, no age limit, orofacial pain, tender points, limited jaw movements and chewing difficulties. Patients with other TMD subtypes or associated musculoskeletal/rheumatologic disease, missing incisors teeth, LLLT contra-indication, and previous TMD treatment were excluded. According to disease duration, patients were allocated into two groups, acute (<6 months) and chronic TMD (≥ 6 months). For each patient, 12 LLLT sessions were performed (gallium-aluminum-arsenide; λ = 830 nm, P = 40 mW, CW, ED = 8 J/cm(2)). Pain intensity was recorded using a 10-cm visual analog scale and maximal mouth opening using a digital ruler (both recorded before/after LLLT). The investigators were previously calibrated and blinded to the groups (double-blind study) and level of significance was 5% (p < 0.05). Fifty-eight patients met all criteria, 32 (acute TMD), and 26 (chronic TMD). Both groups had a significant pain intensity reduction and maximal mouth opening improvement after LLLT (Wilcoxon test, p < 0.001). Between the groups, acute TMD patient had a more significant pain intensity reduction (Mann-Whitney test, p = 0.002) and a more significant maximal mouth opening improvement (Mann-Whitney test, p = 0.011). Low-level laser therapy can be considered as an alternative physical modality or supplementary approach for management of acute and chronic myogenic temporomandibular disorder; however, patients with acute disease are likely to have a better outcome.

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A perda dos dentes naturais é avassaladora para os pacientes e sua reposição com elementos artificiais torna-se essencial para a reabilitação estética, fonética e mastigatória. Porém, a reabilitação protética muitas vezes torna-se insatisfatória em função da falta de tecido de suporte para utilização de prótese, culminando em perda de qualidade de vida. A utilização de próteses sobreimplantes tipo protocolo e overdenture estabeleceu uma opção terapêutica satisfatória e eficiente para a reabilitação oral. O objetivo deste trabalho foi expor e discutir duas situações clínicas distintas de reabilitação onde são comparados os fatores biomecânicos e outros fatores relevantes, como idade, sexo, densidade óssea e dentição antagonista que permitem a reabilitação através de próteses protocolo e overdenture

The loss of natural teeth is overwhelming for patients and their replacement with artificial elements is essential for the rehabilitation, aesthetics, phonetics, and mastication. However, the prosthetic rehabilitation often becomes unsatisfactory due to the lack of supporting tissue for use of prosthesis, resulting in loss of quality of life. The use of implant-supported, total fixed, and overdenture modalities established a satisfactory and efficient treatment for oral rehabilitation options. The objective of this work is to describe and discuss two distinct clinical situations of rehabilitation where biomechanical and other relevant factors are compared, such as age, gender, bone density, and the opposing dentition allowing rehabilitation in both modalities

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A evolução da Implantodontia vem trazendo o desenvolvimento de novas técnicas, que levam cada vez mais conforto ao paciente, seja pelo fato de menos intervenções cirúrgicas com o implante imediato, seja pelo menor tempo que ele passe desdentado, pela técnica da carga imediata. O implante imediato é utilizado, geralmente, logo após a realização de exodontia, para que futuramente seja colocada a prótese. Sua principal vantagem é de redução das etapas cirúrgicas e de evitar a reabsorção óssea, principalmente em áreas estéticas. O uso da carga imediata em implantes tem a finalidade de reduzir o tempo de tratamento, possibilitando que o procedimento protético seja realizado logo após a colocação do implante, porém, o cirurgião-dentista deve saber indicar adequadamente a sua aplicação, seguindo todos os critérios necessários para evitar que ocorram insucessos do tratamento. Este trabalho teve por objetivo revisar a literatura acerca de dois métodos de instalação de implantes, de carga imediata e imediatos, que visem reduzir o tempo de espera pela prótese por parte dos pacientes e apontar suas principais indicações e contraindicações.

he evolution of dental implants has led to the development of new techniques that bring more comfort to the patient, either by the need for fewer surgical interventions with the immediate implant or by the short time period patients spent toothless on immediate loading. The immediate implant is used soon after tooth extraction for prosthesis delivery. Its advantages include reduction of surgical steps and bone resorption, particularly in esthetics areas. The use of immediate loading is intended to reduce overall treatment time, allowing prosthetic installation immediately after implant placement; however, proper indications are necessary as well as the correct protocol for preventing the incidence of treatment failures. This paper aims to review the literature on these two methods for implant placement (immediate implants and immediate loading) which reduce time until prosthesis delivery, highlightening their main indications and drawbacks.

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OBJECTIVE: The aim of the present investigation was to assess histologically the effect of LLLT (GaAIAs, 830 nm, 40 mW, CW, (Phi) approximately 0.6 mm, 16 J/cm(2) per session) on the repair of surgical defects created in the femur of the Wistar Albinus rat. The defects were filled to lyophilized bovine bone (Gen-ox), organic matrix) associated or not to GTR (Gen-derm). BACKGROUND DATA: A major problem on modern Dentistry is the recovery of bone defects caused by trauma, surgical procedures or pathologies. Several types of biomaterials have been used in order to improve the repair of these defects. These materials are often associated to procedures of GTR. Previous studies have shown positive effects of LLLT on the repair of soft tissue wounds, but there are a few on its effects on bone healing. METHODS: Surgical bone defects were created in 42 animals divided into five groups: Group I (control, 6 animals); Group II (Gen-ox, 9 animals); Group III (Gen-ox + Laser, 9 animals); Group IV (Gen-ox + Gen-derm, 9 animals); Group V (Gen-ox + Gen-derm + Laser, 9 animals). The animals on the irradiated group received 16 J/cm(2) per session divided into four points around the defect (4 J/cm(2)) being the first irradiation immediately after surgery and repeated seven times at every 48 h. The animals were humanly killed after 15, 21, and 30 days. RESULTS: The results of the present investigation showed histological evidence of improved amount of collagen fibers at early stages of the bone healing (15 days) and increased amount of well organized bone trabeculae at the end of the experimental period (30 days) on irradiated animals compared to non irradiated ones. CONCLUSIONS: It is concluded that a positive biomodulative effect on the healing process of one defect associated or not to the use of organic lyophilized bone and biological bovine lyophilized membrane on the femur of the rat.

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Um dos maiores problemas na odontologia moderna é a recuperação de perdas ósseas que podem ser ocasionados por trauma, procedimentos cirúrgicos ou por processos patológicos. Diversos tipos de biomateriais tem sido usados na tentativa de melhorar o reparo das mesmas, estes muitas vezes são associados a RTG. Estudos têm evidenciado efeitos positivos da Laserterapia sobre o processo de reparo de feridas de tecidos moles, porém os seus efeitos sobre tecidos ósseo ainda são poucos conhecidos. O objetivo deste trabalho foi avaliar macroscópica e histologicamente, através de microscopia de luz a eficácia da Laserterapia (AsAIGa, λ830nm, P=40mW, CW, Φ ~0,6mm, 16J/cm² por sessão) no reparo ósseo de feridas cirúrgicas em fêmur de ratos da raça Wistar albinos g~enero – macho), submetidas a implante de proteínas morfogenéticas ósseas (BMps – Gen-pro®), associadas ou não a membrana biológica de osso bovino liofilizado desmineralizado (gen-derm®). Feridas ósseas padronizadas (2mm²) foram criadas no fêmur de 96 animais, divididos em oito grupos: Grupo I (controle - 12 animais); Grupo II (Experimental Laser – 12 animais); Grupo III (Experimental Membrana – Gen-derm® - 12 animais); Grupo IV (Experimental Membrana – gen-derm® + Laser – 12 animais); Grupo V (Experimental BMPs – Gen-pro® - 12 animais); Grupo VI (Experimental BMPs – Gen-pro® + Laser – 12 animais); Grupo VII (Experimental BMPs – Gen-pro® + Membrana – Gen-derm® + 12 animais); Grupo VIII (Experimental BMPs – Gen-pro® + Membrana – Gen-derm® + laser – 12 animais). Os grupos experimentais Laser, receberam sete irradiações com intervalos de 48h, sendo a primeira imediatamente após o ato cirúrgico. A dosimetria utilizada foi de 16J/cm² por sessão, divididos em quatro pontos de 4J/cm², perfazendo uma dose total de tratamento de 112J/cm². Os períodos de sacrifício foram de 15, 21 e 30 dias. Os resultados obtidos no presente estudo demonstraram que nas feridas cirúrgicas irradiadas, foi evidenciado histologicame.

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OBJECTIVE: The aim of this study was to histologically assess the effect of low-level laser therapy (LLLT) (lambda830 nm) on the repair of standardized bone defects of the femur of Wistar albinus rats grafted with inorganic bovine bone and associated (or not) with decalcified bovine cortical bone membrane. BACKGROUND DATA: Bone loss may be a result of pathology, trauma, or surgical procedure. Extensive studies on the process of bone repair have been undertaken, and several techniques for the correction of bone defects have been proposed. Amongst them is the use of several types of grafts, the use of membranes, and the combination of both techniques. There is evidence in the literature of the positive effect of LLLT on the healing of soft tissue wounds. However, its effect on bone healing is not completely understood. MATERIALS AND METHODS: Five randomized groups were studied: group I (control); group IIA (Gen-ox); group IIB (Gen-ox + LLLT); group IIIA (Gen-ox + Gen-derm); and group IIIB (Gen-ox + Gen-derm + LLLT). Bone defects were created at the femur and were treated according to the group. The animals of irradiated groups were irradiated every 48 h for 15 days; the first irradiation was performed immediately after the procedure. The animals were irradiated transcutaneuosly at four points around the defect. At each point, a dose of 4 J/cm2 was given (phi approximately equal to 0.6 mm, 40 mW), and the total dose per session was 16 J/cm2. The animals were humanely killed at 15, 21, and 30 days after surgery. The specimens were routinely processed to wax, serially cut, stained with H&E and Picrosirius stains, and analyzed under light microscopy. RESULTS: The results showed more advanced repair of the irradiated groups when compared to the non-irradiated ones. The repair of the irradiated group was characterized by both increased bone formation and on the amount of collagen fibers around the graft within the cavity, as early as the 15th day after surgery, considering the osteoconductive capacity of the Gen-ox and the increment of the cortical repair in specimens with Gen-derm membrane. CONCLUSION: It is concluded that LLLT had a positive effect on the repair of bone defect by graft associated or not with the use of biological membrane.

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The aim of this study was to assess histologically the effect of LLLT (lambda 830 nm) on the repair of standardized bone defects on the femur of Wistar albinus rats which were grafted with inorganic bovine bone Gen-ox(R). Three randomized groups were studied: group I (control, n=6); group II (Gen-ox, n=9) and group III (Gen-ox + LLLT, n=9). The animals were irradiated every 48 h during 15 days; the first irradiation was performed immediately after the procedure. The animals were irradiated transcutaneuosly at four points around the defect. At each point a dose of 4 J/cm(2) was given (Ø approximately 0.6 mm, 40 mW) and the total dose per session was 16 J/cm(2). The animals were killed by an overdose of general anesthetic 15, 21 and 30 days after surgery. The specimens were routinely processed by embedding in paraffin, serially cut and stained with H&E and Picrosirius and analyzed under light microscopy. The results showed evidence of a more advanced repair in the irradiated group when compared to the non-irradiated groups. The repair of the irradiated group was characterized by both increased bone formation and amount of collagen fibers around the graft within the cavity from the 15th day after surgery, also considering the osteoconductive capacity of the Gen-ox. We conclude that LLLT had a positive effect on the repair of bone defects implanted with inorganic bovine bone.

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O objetivo deste trabalho foi avaliar histologicamente a influência da radiação laser não-cirúrgica (830 nm) sobre o reparo ósseo de defeitos padronizados em fêmur de ratos Wistar albinus e submetidos a implante de osso bovino inorgânico Gen-ox. Foram estabelecidos três grupos de animais: grupo I (controle, n=06); grupo II (Gen-ox, n=09) e grupo III (Gen-ox + LLLT, n=09). Os animais foram irradiados a cada 48 horas, sendo a primeira irradiação realizada imediatamente após a cirurgia. Os animais foram irradiados transcutaneamente em quatro pontos em torno da ferida. Cada ponto recebeu uma dose de 4 J/cm2 e a dose total por sessão foi de 16 J/cm2. Os sacrifícios foram realizados 15, 21 e 30 dias após a cirurgia. Os espécimes foram removidos e fixados para procedimento laboratorial, sendo corados com HeE e Picrosirius e analisados em microscopia de luz. Os resultados mostraram evidência de um reparo ósseo mais avançado nos espécimes irradiados em relação aos não irradiados. O reparo nos espécimes irradiados foi caracterizado por uma maior neoformação óssea, bem como por uma maior proliferação de fibras colágenas no interior do defeito já a partir de 15 dias após a cirurgia, também considerando a capacidade osteocondutiva do Gen-ox. Conclui-se que a LLLT resultou num efeito de biomodulação positiva sobre o reparo do defeito ósseo submetido a implante de osso bovino inorgânico.

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