Periodontitis in rheumatoid arthritis: a case-control study in a brazilian sample

To investigate the presence of periodontitis in RA patients comparing it with controls in a Brazilian sample. Methods: This is a case control study conducted in a public health rheumatologic center. One hundred and sixteen RA patients and 68 paired controls were compared for epidemiological data and presence of periodontal disease evaluated by number of remaining teeth, presence of bacterial plaque, bleeding on probing, probing depth and clinical level of gingival insertion. In addition, data on comorbidities was collected. Results: RA patients and controls have the same amount of teeth loss (P = 0.84). RA patients had more calculus (P = 0.02); dental plaques (P = 0.04); gingival recession (P = 0.02) and bleeding (P = 0.01). Although the number of individuals with periodontitis was higher in RA patients, the severity of periodontitis was similar in both groups (P = ns). Presence of diabetes and hypothyroidism also associated with periodontitis (P = 0.01 and 0.02 respectively). In a model of logistic regression built to assess the independence of association of RA and its comorbidities with periodontitis, only diabetes and RA remained independent. Conclusion: This case control study shows higher frequency of periodontitis in RA patients than controls

Câncer de pele não melanoma: revisão integrativa / Non-melanoma skin cancer: an integrative review

Introdução: O câncer de pele não melanoma compeende grupo de neoplasias com alta incidência na população mundial. É dividido em carcinoma basocelular e de células escamosas. Por ser de grande prevalência, entender o processo de oncogênese e a relação com íons, proteínas e receptores celulares no câncer de pele não melanoma pode contribuir para que novas terapêuticas sejam avaliadas. Objetivo: Entender o processo da oncogênese dos tumores de pele não melanomas e sua relação com a imunolocalização do IP3R. Métodos: Revisão integrativa da literatura com síntese de evidências. A base de dados foi o PubMed; a estratégia de busca: "carcinoma espinocelular, AND/ OR carcinoma basocelular, AND/OR IP3R, AND/OR imunoistoquímica". Foram considerados para revisão os trabalhos publicados entre 2018 e 2023. Foram incluídos 40 trabalhos, integralmente lidos e resumidos. Resultados: Câncer de pele não melanoma são os tumores malignos mais comuns em todo o mundo, sendo 75-80% o carcinoma basocelular, e até 25% o de células escamosas. As interações moleculares de forma geral, envolvem grande participação de moléculas supressoras tumorais, assim como de procto-oncogenes. Além disso, canais iônicos voltagem dependente controlam o fluxo citosólico de íons, dentre eles o cálcio. O IP3R (receptor do fosfatidil inositol-3) permite a saída de cálcio do retículo endoplasmático para que seja utilizado pela célula para atividades fisiológias como proliferação, angiogênese, motilidade e capacidade de invasão. Conclusão: O IP3R, pelas características de expressão imunoistoquímica, parece estar relacionado também, à fisiopatologia do câncer de pele não melanoma.

Introduction: Non-melanoma skin cancer comprises a group of neoplasms with a high incidence in the world population. It is divided into basal cell carcinoma and squamous cell carcinoma. As it is highly prevalent, understanding the process of oncogenesis and the relationship with ions, proteins and cellular receptors in nonmelanoma skin cancer can contribute to the evaluation of new therapies. Objective: To understand the oncogenesis process of non-melanoma skin tumors and its relationship with the immunolocalization of IP3R. Methods: Integrative literature review with evidence synthesis. The database was PubMed; the search strategy: "squamous cell carcinoma, AND/OR basal cell carcinoma, AND/OR IP3R, AND/OR immunohistochemistry". Works published between 2018 and 2023 were considered for review; 40 works were included, fully read and summarized. Results: Non-melanoma skin cancer is the most common malignant tumor worldwide, with 75-80% being basal cell carcinoma, and up to 25% being cell carcinoma. Molecular interactions in general involve a large participation of tumor suppressor molecules, as well as procto-oncogenes. Furthermore, voltage-dependent ion channels control the cytosolic flow of ions, including calcium. The IP3R (phosphatidyl inositol-3 receptor) allows the exit of calcium from the endoplasmic reticulum so that it can be used by the cell for physiological activities such as proliferation, angiogenesis, motility and invasion capacity. Conclusion: The IP3R, due to its immunohistochemical expression characteristics, appears may also be related to the pathophysiology of nonmelanoma skin cancer.

Platelet-rich fibrin improves the osteoneogenesis in non-critical defects in calvaria: a histological and histometric study

ABSTRACT Purpose: The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF) and autograft on non-critical bone repair. Methods: Four bone defects (8.3 × 2 mm) were produced on the calvarium of 15 rabbits. The surgical defects were treated with either autograft, autograft associated to PRF, PRF alone, and sham. Animals were euthanized on the second, fourth or sixth posteoperative week. Histological analyses for presence of bone development on deffect was evaluated comparing the groups treated with autograft and without the autograft separately within the same period. Mann-Whitney's tests were used to compare the percentage of bone repair in each post-operative period for autograft × autograft + PRF groups and also for control × PRF groups (α = 5%). Results: No differences were observed between the groups that received autograft and autograft associated to PRF on the second and fourth postoperative week, but areas treated with PRF demonstrated significant osteogenesis when compared to sham group on the fourth and sixth weeks. The groups that received PRF (with autograft or alone) demonstrated an enlarged bone deposition when compared to their control group. Conclusions: The use of PRF may influence bone repair and improve the bone deposition in late period of repair demonstrating osteoconductive and osteogenic properties.

Co-Occurrence of Pineal-Region and Pituitary-Stalk Hemangioblastomas in a Patient Presenting with Von Hippel-Lindau Disease ­ A Case Report

Introduction Hemangioblastomas of the pineal region or pituitary stalk are extremely rare. Only two cases of hemangioblastomas involving the pineal region have been reported, and four involving the pituitary stalk. The purpose of the present manuscript is to describe an unusual case of supposed hemangioblastoma found concomitantly in the pineal region and pituitary stalk of a patient diagnosed with Von Hippel-Lindau (VHL) disease. Case Report A 35-year-old female patient with a previous diagnosis of VHL complaining of occipital headaches and balance disturbances for three weeks, who previously had a cerebellar hemangioblastoma resected. The visual characteristics of the tumor suggested a friable vascular lesion with a reddish-brown surface, and an incisional biopsy was performed. The tumor consisted of a dense vascular network surrounded by fibrous stroma abundant in reticulin and composed by both fusiform and dispersed xanthomatous cells; the immunohistochemistry was immunopositive for neuronspecific enolase and immunonegative for epithelial membranous antigen. The patient has been monitored closely for 2 years, and the supratentorial masses have not presented any volume alteration. Conclusion This rare association must be taken into account in patients with VHL disease, or at least be suspected in patients who present a thickening of the pituitary stalk and a pineal-region mass. We believe a biopsy of our asymptomatic patient could have been dangerous due to inherent complications like intraoperative bleeding. We recommend close observation of asymptomatic lesions with MRIs every six months or until the lesions become symptomatic. If the pineal-region tumor does become symptomatic, gross resection via a transcallosal approach would be ideal.

Software-assisted image analysis for identification and quantification of hepatic sinusoidal dilatation and centrilobular fibrosis / Análise da imagem histológica assistida por software para identificação e quantificação de dilatação sinusoidal e fibrose hepática centrolubular

ABSTRACT Background: Heart dysfunction and liver disease often coexist because of systemic disorders. Any cause of right ventricular failure may precipitate hepatic congestion and fibrosis. Digital image technologies have been introduced to pathology diagnosis, allowing an objective quantitative assessment. The quantification of fibrous tissue in liver biopsy sections is extremely important in the classification, diagnosis and grading of chronic liver disease. Aim: To create a semi-automatic computerized protocol to quantify any amount of centrilobular fibrosis and sinusoidal dilatation in liver Masson's Trichrome-stained specimen. Method: Once fibrosis had been established, liver samples were collected, histologically processed, stained with Masson's trichrome, and whole-slide images were captured with an appropriated digital pathology slide scanner. After, a random selection of the regions of interest (ROI's) was conducted. The data were subjected to software-assisted image analysis (ImageJ®). Results: The analysis of 250 ROI's allowed to empirically obtain the best application settings to identify the centrilobular fibrosis (CF) and sinusoidal lumen (SL). After the establishment of the colour threshold application settings, an in-house Macro was recorded to set the measurements (fraction area and total area) and calculate the CF and SL ratios by an automatic batch processing. Conclusion: Was possible to create a more detailed method that identifies and quantifies the area occupied by fibrous tissue and sinusoidal lumen in Masson's trichrome-stained livers specimens.

Resumo Racional: Tecnologias de imagem digital têm sido introduzidas ao diagnóstico patológico, permitindo avaliações quantitativas objetivas. A quantificação de tecido fibroso em biópsias de fígado é extremamente importante para a classificação, diagnóstico e graduação de doenças crônicas hepáticas. Objetivo: Criar um protocolo computadorizado semi-automático para quantificação de fibrose centrolobular e dilatação sinusoidal em amostras de fígado coradas por Tricrômico de Masson. Método: Uma vez instaurada a fibrose, amostras de fígado foram coletadas, processadas histologicamente, coradas por Tricrômico de Masson e WSI (Whole Slide Images) foram capturadas por scanner digital patológico apropriado. Uma seleção aleatória das regiões de interesse (ROI) foi realizada. Os dados foram submetidos a uma análise de imagem assistida por software (ImageJ®). Resultados: A análise de 250 ROIs permitiu obter-se empiricamente as melhores configurações capazes de identificar fibrose centrolobular (FC) e lúmen sinusoidal (LS). Após o estabelecimento das configurações de padrão de cor, uma Macro de autoria própria foi gravada para definir as medidas (área da fração e área total) e calcular as razões de FC e LS por processamento em grupo/lote (batch mode). Conclusão: Foi possível criar um método detalhado capaz de identificar e quantificar a área ocupada por tecido fibroso e lúmen sinusoidal em espécimes de fígado coradas por Tricrômico de Masson.

Platelet-concentrated and platelet poor-plasma promote different pattern on immunohistochemical expression of TGF-β1, however they impairs the osteoneogensis in calvarial defects treated with autograft due suppression of osteocalcin

ABSTRACT Purpose Herein we evaluated the effects of platelet concentrate (PC) and platelet-poor plasma (PPP) on bone repair using noncritical defects in the calvaria of rabbits and compared them to the presence of TGF-β1 and osteocalcin on reparative sites. Methods Five noncritical defects of 8.7 mm in diameter were created on the calvaria of 15 animals. Each defect was treated differently, using autograft (ABG), ABG associated with PC (ABG + PC), ABG with PPP (ABG + PPP), isolated PPP, and blood clot (control). The animals were submitted to euthanasia on the second, fourth and sixth week post-surgery. Results The defects that received ABG+PC or PPP demonstrated lower bone formation when compared to specimens that received ABG in the same period. These results coincided to significant higher immunopositivity for TGF-β1 for specimens that received PC, and lower presence of cytokine in the group PPP. However, either higher or lower presence of TGF-β1 were also correlated to lower presence of osteocalcin. Likewise, these results were similar to findings in specimens treated only with PPP when compared to control. Conclusions PC and PPP were not effective when applied in association with ABG. Similarly, isolated use of PPP was not beneficial in optimizing the bone repair.

Dano histológico renal em modelo experimental de hipertrofia ventricular direita induzida por monocrotalina / Renal histological damage in an experimental model of monocrotalin-induced right ventricular hypertrophy

Monocrotalina, alcalóide tóxico obtido de plantas do gênero crotalaria, pode ter potencial efeito tóxico em órgãos do corpo humano, como rins, pulmões, coração, fígado e outros efeitos. O objetivo deste estudo foi avaliar o dano renal causado pela exposição à monocrotalina. Trata-se de estudo experimental em ratos divididos em 4 grupos, um dos quais recebeu injeção de soro fisiológico e os outros três inoculação de monocrotalina, com tempos diferentes para sacrifício; subsequentemente, estudo histológico foi feito a fim de evidenciar as lesões renais. Em conclusão, constatou-se que houve lesão renal. Contudo, não foi possível afirmar o mecanismo exato responsável por elas, ou seja, se foram decorrentes da ação tóxica direta da monocrotalina, ou se, também, esteve relacionado a outros fatores sistêmicos.

Monocrotaline, a toxic alkaloid obtained from plants of the Crotalaria genus, may have a potential toxic effect on human body organs, such as kidneys, lungs, heart, liver and other effects. The aim of this study was to evaluate the kidney damage caused by exposure to monocrotaline. This is an experimental study in rats divided into 4 groups, one of which received saline injection and the other three received monocrotaline inoculation, with different times for sacrifice; subsequently, a histological study was performed in order to evidence renal lesions. In conclusion, it was found that there was kidney damage. However, it was not possible to state the exact mechanism responsible for them, that is, if they were due to the direct toxic action of monocrotaline, or if it was also related to other systemic factors.

Traumatic myositis chondro-ossificans of masseter muscle associated with TGF-β1, Indian Hegdehog, BMP2, osteopontin and osteocalcin upregulation: Case report

Masseter traumatic myositis chondro-ossificans (TMCO) is a rare pathological condition that causes severe mandibular function restriction. The aim of the present study is to report a TMCO case after direct masseter muscle injury and correlate it to bone and cartilage biomarkers up-regulation. Caucasian male patient, 38 years old, seeks treatment nine days after trauma with severe mouth opening limitation. Physical examination revealed a circumscribed hardened area connected to masseter muscle on the left side. Cone beam tomography and ultrasonography of masseter region were requested. There was incomplete fracture between the posterior board of inferior jaw and coronoid process as well as calcification within masseter muscle. The proposed treatment was excisional biopsy of calcification, coronoid process removal to enhance mouth opening as well as incomplete condyle fracture monitoring. Material removed was sent for histological analysis in order to confirm diagnosis. Immuhistochemistry was conducted and it was found that chondro-ossification biomarkers such as TGF-b1, Indian Hegdehog (IHH), BMP2, osteopontin (OP) and osteocalcin (OC) were up-regulated. One-year follow-up showed that the patient is stable with increased mouth opening and satisfactory jaw movements. Pathologists and maxillofacial surgeons must be aware of differential diagnosis of TMCO. Understanding cellular mechanisms of muscle tissue after trauma is also important once cellular pathway modifications leads to clinical features that differ from previously described in literature.

The influence of early bisphosphonate treatment in bone reconstruction on craniofacial radiographic bone density / A influência do tratamento com bisfosfonatos na densidade óssea em área de reconstrução óssea craniofacial

Objective: To evaluate the effects of alendronate (AL), a bisphosphonate, on visual bone density by means of a radiographic analysis. Material and methods: Sixty-two Wistar rats were divided into four groups: Group AA (AL with autogenous graft); group AW (AL without autogenous graft) both receiving AL on alternate days for 4 weeks before surgery; control group CA (with autogenous graft); group CW (without autogenous graft) both receiving saline solution before surgery. Experimental periods of evaluation were 2 weeks and 4 weeks postsurgery. Conventional and digital radiographs were obtained, and a 5-point grading system (score) was used to assess visual radiographic bone density. Results: There were no statistical differences between CA and AA groups at 2 and 4 weeks. The AA group had a higher mean score of bone density than the CW and AW groups at 2 weeks (P < 0.05). The CA and AA groups had higher scores of bone density than the CW and AW groups at 4 weeks (P < 0.05). Conclusions: Treatment with AL did not affect radiographic bone density at 2 and 4 weeks after surgery. The presence of an autograft resulted in higher scores of bone density. (AU)

Objetivo: Avaliar os efeitos do alendronato (AL), um bisfosfonato, na densidade óssea através de uma análise radiográfica. Material e métodos: Sessenta e dois ratos Wistar foram divididos em quatro grupos: Grupo AA (AL com enxerto ósseo autógeno); grupo AW (AL sem enxerto ósseo autógeno); ambos receberam AL em dias alternados durante 4 semanas antes da cirurgia; grupo controle CA (com enxerto ósseo autógeno); grupo CW (sem enxerto ósseo autógeno) ambos receberam solução salina antes da cirurgia. Os tempos experimentais de avaliação foram 2 e 4 semanas após a cirurgia. Radiografias convencionais e digitais foram realizadas, e um sistema de escore de 5 pontos foi utilizado para avaliar a densidade óssea radiográfica visualmente. Resultados: Não houve diferença estatisticamente significativa entre os grupos CA e AA em 2 e 4 semanas. O grupo AA apresentou maior escore de densidade óssea do que os grupos CW e AW em 2 semanas (p < 0.05). Os grupos CA e AA apresentaram maior escore de densidade óssea do que os grupos AW e CW em 4 semanas (p < 0.05). Conclusões: O tratamento com AL não interferiu na densidade óssea radiográfica em 2 e 4 semanas após cirurgia. A presença do enxerto resultou em maior escore de densidade óssea. (AU)

Effect of local application of alendronate and parathyroid hormone on craniofacial bone repair - a preliminary study

Abstract This study aimed to evaluate the effect of two methods of local application of alendronate and parathyroid hormone (PTH) on bone repair and the systemic implications. A critically sized defect (5 mm) was created in the cranial region of twenty-five male Wistar rats, and the bone removed was particulated, and grafted back to the defect with different treatments. The animals were randomly divided into five groups: A1- bone graft immersion in alendronate solution (3 mg/kg) for 5 minutes; P1- bone graft immersion in PTH solution (20 µg); A2- weekly local applications of alendronate 1 mg/kg; P2- weekly local applications of PTH (20 µg); C- no drugs were used. The animals were euthanized 60 days after surgery. Cranial bone blocks were removed for histological, histomorphometric, and immunohistochemical analyses. MMP-2 and MMP-9 were used for immunolabeling. The kidneys, liver, and brain were also removed from all the rats for histological analysis. The data were submitted for statistical analysis with a level of significance of 0.05 (One-way ANOVA). The group C and group P2 presented a higher quantity of viable bone particles than the remaining groups. Groups A1, A2, and P1 presented with fewer viable bone particles than the control group, with a predominance of non-mineralized connective tissue. The histomorphometric analysis revealed no differences in relative bone area or MMP-2 or MMP-9 immunolabeling between the groups (p>0.05). Group A2 showed presence of fat in the liver consistent with hepatic steatosis. Changes in brain tissue were observed in groups A1 and P1.

Resumo Este estudo visou avaliar o efeito de dois métodos de aplicação local de alendronato e de paratormônio (PTH) no reparo ósseo e avaliar as implicações sistêmicas. Um defeito de tamanho crítico (5 mm) foi criado na calota craniana de vinte e cinco ratos Wistar machos, e o osso removido foi particulado e enxertado de volta no defeito com diferentes tratamentos. Os animais foram divididos aleatoriamente em cinco grupos: A1: imersão do enxerto ósseo em solução de alendronato (3 mg/kg) durante 5 min; P1- imersão do osso em solução de PTH (20 μg); A2- aplicações locais semanais de alendronato 1 mg/kg; P2- aplicações locais semanais de PTH 20 μg; C: não foram utilizados medicamentos. Os animais foram eutanasiados 60 dias após a cirurgia. Foram removidos os blocos ósseos envolvendo a região do defeito para realização das análises histológica, histomorfométrica e imuno-histoquímica. MMP2 e MMP9 foram as imunomarcações utilizadas. Os rins, fígado e cérebro também foram removidos de todos os ratos para análise histológica. Os dados foram submetidos à análise estatística com um nível de significância de 0,05 (One-way ANOVA). A análise histológica revelou que o grupo C e o grupo P2 apresentaram maior quantidade de partículas ósseas viáveis do que as apresentadas pelos demais grupos. Os grupos A1, A2 e P1 apresentaram menos partículas ósseas viáveis em comparação com o grupo controle com predominância de tecido conjuntivo não mineralizado. A análise histomorfométrica não revelou diferenças entres os grupos na área óssea relativa ou em MMP2 e MMP9 (p>0,05). O grupo A2 mostrou presença de gordura no fígado consistente com esteatose hepática. Alterações no tecido cerebral foram observadas nos grupos A1 e P1.

Oral and masticatory rehabilitation using osseointegrated dental implants after resective treatment of multicystic ameloblastoma in the lower jaw with a fibula graft

Ameloblastoma is an aggressive odontogenic tumor which typically occurs between third and fourth decade of life that often needs resective approach. Immediate reconstruction may show better results. The treatment of multicystic ameloblastoma in the mandible being a rare case that occurred in the late second decade of life, which was surgically removed along with the affected teeth with safety margins, and the region was immediately reconstructed using a vascularized graft, removed from the fibula. Its integration, in combination with osseointegrated dental implants and fixed implant-supported prostheses, restored chewing function and esthetics. After 6 years from fibular graft and 24 months of dental implants, an excellent outcome was observed, with oral health and normal functions properly restored, and the immediate reconstruction of the mandible in resective cases, associated with oral rehabilitation with dental implants, may be considered a suitable treatment option.

Saúde bucal e periodontal podem ser afetadas após cirurgia bariátrica e deficiências nutricionais? / an oral and periodontal health may be affected after bariatric surgery and nutritional deficiencies?

Objetivo: tentar entender como as deficiências nutricionais no paciente pós-operatório à cirurgia bariátrica impactam a saúde oral e periodontal. Material e métodos: uma pesquisa na base de dados PubMed com os termos "by-pass gástrico e doenças periodontais", "cirurgia bariátrica e deficiências nutricionais", e "saúde bucal e obesidade" tentando esclarecer a relação com doença periodontal e as deficiências nutricionais. Resultados: foi realizada uma revisão de artigos sobre o fato da cirurgia bariátrica ser um procedimento cirúrgico indicado para o tratamento da obesidade mórbida e promover alteração da anatomia gastrintestinal, levando à perda de peso, diminuindo a absorção de açúcares, gorduras e outros nutrientes importantes, como vitaminas A, C, D, B12, cálcio e ferro, responsáveis pela regulação de muitas funções críticas no organismo e participantes efetivos na produção de colágeno e matriz óssea. Conclusão: a cavidade oral sofre complicações em vista dessa nova situação, e os dentistas precisam entender como essas deficiências podem afetar na doença periodontal, a fim de desenvolver estratégias de prevenção e tratamento para este novo grupo de população.

Objective: the aim of this article is try to understand how the nutritional deficiencies in the post-operative patient submitted to bariatric surgery impact on oral and periodontal health. Material and methods: a survey in PubMed database with these terms "gastric by-pass and periodontal diseases", "bariatric surgery and nutritional deficiencies" and "oral health and obesity" was done trying to clarify the relationship with periodontal disease. Results: bariatric surgery is a surgical procedure indicated for the treatment of morbid obesity and promotes an alteration of gastrointestinal anatomy leading to a marked weight loss by decreasing the absorption of sugars and fats, but other important nutrients such as decreased absorption of vitamins A, C, D, B12, calcium and iron, which are also responsible for the regulation of many critical functions in organism, and effectively participate in the production of collagen and bone matrix and an overview of papers about this topic was conducted. Conclusion: the oral cavity suffers complications from this new situation and dentists need to understand how these deficiencies may impact on periodontal disease in order to develop treatment and prevention strategies for this new population group.

Evaluating surfaces of titanium dental implants after contact with surgical gloves, steel rongeur, and titanium tweezers using scanning electron microscopy

Introduction and Objective: To use scanning electron microscopy (SEM) and determine whether the surfaces of titanium implants are damaged when touched with a steel rongeur, titanium tweezers, or surgical gloves. Material and methods: Ten dental implants were divided into five groups: Control (C), Titanium Tweezers (T-T), Steel Rongeurs (S-R), Surgical Gloves (S-G), and Steel Support (S-S). The implants were assembled in a metallic base (stub) with the aid of copper strips. They were then imaged and their microstructures were characterized using SEM. Results: An analysis of the obtained images showed that the implants that had been handled with titanium tweezers or a steel rongeur suffered some damage to their physical structure; "scratches" and other small signs of damage were visible on their surfaces. The affected areas were very small compared to the total surface area of the implants. Small dark local stains were observed at the spots where some of the implants had rubbed against a steel support. The rubbing of the implants against the support did not cause any structural damage. The implants handled with surgical gloves exhibited many dark stains their surfaces. This suggested that the powder from the surgical gloves had contaminated the surfaces of the implants. Conclusion: Using SEM imaging, it was determined that the surfaces of dental implants suffer minor physical damage when handled with various pieces of dental equipment. However, the damage should not result in failure of the osseointegration process. In vivo studies are needed to confirm this hypothesis.

Investigation of the influence of design details on short implant biomechanics using colorimetric photoelastic analysis: a pilot study

Introduction : The clinical survival of a dental implant is directly related to its biomechanical behavior. Since short implants present lower bone/implant contact area, their design may be more critical to stress distribution to surrounding tissues. Photoelastic analysis is a biomechanical method that uses either simple qualitative results or complex calculations for the acquisition of quantitative data. In order to simplify data acquisition, we performed a pilot study to demonstrate the investigation of biomechanics via correlation of the findings of colorimetric photoelastic analysis (stress transition areas; STAs) of design details between two types of short dental implants under axial loads. Methods Implants were embedded in a soft photoelastic resin and axially loaded with 10 and 20 N of force. Implant design features were correlated with the STAs (mm2) of the colored fringes of colorimetric photoelastic analysis. Results Under a 10 N load, the surface area of the implants was directly related to STA, whereas under a 20 N load, the surface area and thread height were inversely related to STA. Conclusion A smaller external thread height seemed to improve the biomechanical performance of the short implants investigated.

Non-Pedicled Buccal Fat Pad Grafts to Treatment for Class I and II Gingival Recessions: A Clinical Trial

The aim of this study was to analyze the transplant efficiency of non-pedicled buccal fat pad graft (BFPG) for the treatment of Miller Class I or II gingival recessions (GRs) and to compare these results with those of subepithelial connective tissue graft (SCTG), which is considered the gold standard. Twelve patients with Miller Class I or II (≥2 mm) bilateral recessions in maxillary premolars or canines were selected. Recessions were randomly assigned to receive SCTG or BFPG. The clinical parameters evaluated at baseline and at 1, 3, and 6 months postoperatively included gingival index, plaque index, probing depth, GR, clinical attachment level, width of keratinized tissue, thickness of keratinized tissue and gingival margin to the acrylic guide. None of the evaluated clinical parameters differed significantly between the groups. At all evaluated postoperative time-points, both groups exhibited statistically significant differences in GR and gingival margin to the acrylic guide compared to baseline. Six months after surgery, the mean percentages of root coverage were 67.5% and 87.5% in the BFPG and SCTG groups respectively. In both groups, complete root coverage was observed in 50% of cases 6 months after surgery. The results presented herein indicate that the use of BFPG transplant has clinical similarities with SCTG and both may be considered as clinically successful methods for treating Miller Class I and II GRs.

Resumo O objetivo deste estudo foi analisar a eficiência do transplante do enxerto de tecido adiposo bucal não pediculado (ETAB) para o tratamento de recessões gengivais Classe I e II de Miller e comparar seus resultados com o enxerto de tecido conjuntivo (ETC), que é considerado o enxerto padrão ouro. Foram selecionados 12 pacientes com recessões gengivais bilaterais Classe I e II de Miller presentes em canino ou pré-molares maxilares. As recessões foram randomizadas para receber um dos dois tratamentos ETAB ou ETC. Os parâmetros clínicos avaliados no baseline e com 1, 3 e 6 meses de pós-operatório foram o índice gengival, índice de placa, profundidade de sondagem, recessão gengival (RG), nível clinico de inserção, espessura e largura de tecido queratinizado e a medida da margem gengival ao guia de acrílico (MG-GA). Os resultados mostraram que não houve diferença estatisticamente significativa entre os grupos em nenhum dos parâmetros clínicos avaliados. Os parâmetros clínicos de RG e MG-GA, em ambos os grupos, apresentaram diferença estatisticamente significativa nos 3 períodos pós-operatórios em relação ao baseline. Aos 6 meses de pós-operatório, a média percentual de recobrimento radicular foi de 67,5% e 87,5% para o grupo ETAB e ETC respectivamente. Em ambos os grupos o recobrimento radicular completo foi em 50% dos casos após 6 meses de pós-operatório. Pode-se concluir que o transplante do ETAB apresentou similaridades clínicas com o ETC e ambos os tratamentos podem ser considerados de sucesso clínico para o tratamento de RGs Classe I e II de Miller.

Effect of Chlorhexidine on Dentin Bond Strength of Two Adhesive Systems after Storage in Different Media

The aim of this study was to evaluate the effect of 2% chlorhexidine (CHX) application during the bonding protocol on microshear bond strength of two adhesive systems, after storage in different media. Seventy-two human molars had their crowns cut in half and embedded in PVC cylinders with acrylic resin. The specimens were randomly divided into experimental groups (n=12) according to the adhesive system (Ambar and Single Bond 2), use of CHX in the bonding protocol, and time interval (24 h and 15 days) in the storage media (distilled water, mineral oil and 1% sodium hypochlorite - NaOCl). Adhesive systems were applied in accordance to manufacturers' recommendations, with or without the use of CHX, and resin composite (Z350 XT) cylinders were placed on the hybridized dentin. After photoactivation, the specimens were stored in distilled water, mineral oil and 1% NaOCl for 24 h and 15 days. Microshear bond strength was determined at a crosshead speed of 0.5 mm/min until fracture. The bond strength data were analyzed statistically by 4-way ANOVA and Tukey's test (α=5%). Use of CHX in the bonding protocol did not cause loss of bond strength in any of the evaluated situations, irrespective of time and storage medium. The storage medium had no influence on bond strength values after 15 days when the bond protocol without CHX application was used. However, the use of CHX in the protocol influenced negatively the bond strength values for Single Bond 2 after 15 days storage in distilled water and 1% NaOCl.

Resumo O objetivo deste trabalho foi avaliar o efeito da aplicação de clorexidina 2% (CHX) na resistência de união (RU) ao microcisalhamento de dois sistemas adesivos após armazenagem em diferentes meios. Setenta e duas coroas de molares humanos foram cortadas e incluídas em cilindros de PVC. Os espécimes foram distribuídos aleatoriamente nos grupos (n=12), segundo o sistema adesivo (Ambar e Single Bond 2), uso ou não de CHX e o tempo (24 h e 15 dias) e meio de armazenamento (água destilada, óleo mineral e hipoclorito de sódio 1% - NaOCl). Os sistemas adesivos foram aplicados de acordo com as recomendações do fabricante, com e sem o uso de CHX, e cilindros de resina composta (Z350 XT) foram colocados sobre a dentina já hibridizada. Após a fotoativação, os espécimes foram armazenados em um dos três meios (água destilada, óleo mineral e NaOCl a 1%) a 37 ºC por 24 h e 15 dias. RU foi determinada pelo ensaio de microcisalhamento, com velocidade de 0,5 mm/min. Os dados foram analisados por ANOVA a quatro fatores e teste de Tukey (α=5%). O uso da CHX não provocou perda de RU em nenhuma das situações avaliadas, independentemente do tempo e meio de armazenamento. Não houve influência do meio de armazenamento na RU após 15 dias quando foi utilizado o protocolo adesivo sem a aplicação de CHX. Porém, a utilização de CHX influenciou negativamente os valores de RU para o Single Bond 2 após 15 dias de armazenamento em água destilada e NaOCl a 1%.

Platelet-leukocyte-rich plasma (L-PRP) prevents the collagen III degradation and impairs the bone matrix development in artificial defect of rabbit calvaria, associated with suppression of the immunohistochemical expression of MMP-2 and MMP-9

Introduction and Objective: Because L-PRP constitutes an important source of growth factor that is associated with osteogenesis and fibrogenesis, the aim of this study was to evaluate the effect of L-PRP on the presence of collagen III and MMP-2 and MMP-9, while comparing these results by means of a histomorphometric analysis of bone matrix and fibrous deposition on bone repair. Material and methods: Four bone defects of 8 × 2 mm were created on the calvaria of 21 rabbits. The surgical defects were treated with either particulate autograft, particulate autograft mixed with L-PRP, or L-PRP alone. Animals were euthanized at 2, 4, and 6 weeks postoperative. Histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of collagen III and MMPs. Results: In contrast to the results of the L-PRP-free groups, the histomorphometric results of the L-PRP groups demonstrated intense fibrotic deposition along with hindered bone matrix deposition. These results coincided with the larger occurrence of diffuse collagen III deposition and the scarce presence of MMP- 2 and -9 spread among the fibrous tissue. Conclusion: Thus, the results suggest that L-PRP not only induces an intense fibrosis rich in collagen III, which is not degraded, but also suppresses MMP-2 and -9 expressions, mimicking a similar pathological event as that of a cleft-palate or cranial suture.

Correlation Between Radiographic Area and Immunolocation of MMP-2 and MMP-9 in Unilocular Radiographic Lesions

Unilocular bone cysts are the most common entities affecting the maxillofacial region. The mechanism of proliferation and expansion remains unclear. Metalloproteinases (MMPs) are associated to diverse pathological conditions. The aim of the present study was to correlate the radiographic aspect (area) and the presence of MMP-2 and MMP-9 in dentigerous cysts, radicular cysts and keratocystic odontogenic tumors. The radiographic area of each lesion was calculated using the mathematical formula of the ellipse area. All specimens were subjected to immunohistochemical analysis for these enzymes. The average radiographic area was 284.17 mm2, 235.81 mm2 and 381.81 mm2, respectively. Statistical analyses revealed no association between the immunoreactivity of MMPs and radiographic area of the lesions in all pathologies studied, except for MMP-2 and radicular cysts, for which smaller lesions had increased immunostaining for this enzyme. The results demonstrate that quantities of MMP-2 and MMP-9 are especially involved with dentigerous and radicular cysts in expansion, whereas these enzymes seem to be related to the biological behavior of keratocystic odontogenic tumors, indicating invasion and cell proliferation. Moreover, there is an inverse association between MMP-2 and MMP-9 in keratocystic odontogenic tumors (p=0.03; rs=-0.660), indicating activity in different regions.

Cistos ósseos uniloculares são as entidades mais comuns que afetam a região maxilofacial. O mecanismo de proliferação e expansão permanece obscuro. As metaloproteinases (MMPs) estão associadas a diversas condições patológicas. O objetivo do presente estudo foi correlacionar o aspecto radiográfico (área) e a presença de MMP-2 e MMP-9 em cistos dentígeros, cistos radiculares e tumores odontogênicos queratocísticos. A área radiográfica de cada lesão foi calculada usando a fórmula matemática da área de elipse. Todas as amostras foram submetidas à análise imunoistoquímica para estas enzimas. A área radiográfica média foi de 284,17 mm2, 235,81 mm2 e 381,81 mm2, respectivamente. As análises estatísticas não mostraram associação entre a imunorreatividade de MMPs e área radiográfica das lesões em todas as patologias estudadas, exceto para MMP-2 e cistos radiculares, nas quais as lesões menores tinham maior imunomarcação para esta enzima. Os resultados demonstraram que a quantidade de imunomarcação da MMP-2 e MMP-9 estão envolvidos com cistos dentígeros e radiculares na expansão óssea, ao passo que estas enzimas parecem estar relacionados com o comportamento biológico dos tumores odontogénicos queratocísticos, indicando invasão e proliferação celular. Além disso, há uma relação inversa entre a MMP-2 e MMP-9 em tumores odontogénicos queratocísticos (p=0,03; rs= -0,660), indicando atividade em diferentes regiões.

Immunoexpression of PPAR-? and Osteocalcin Proteins for Bone Repair of Critical-Size Defects Treated with Fragmented Autogenous Abdominal Adipose Tissue Graft

Immunoexpression of PPAR-γ and osteocalcin proteins was evaluated for bone repair of critical-size defects (CSDs), created in rat calvaria (n=42) and treated with fragmented abdominal autogenous adipose tissue graft. Three groups (n=14) were formed: C (control - blood clot), AB (autogenous bone) and AT (fragmented adipose tissue). The groups were divided into subgroups (n=7) for euthanasia at 30 and 90 days. Histological and immunohistochemical analyses were performed. Data were subjected to descriptive statistics (mode). A complete bone closure was observed in Group AB 90 days after surgery. In Group C, repair was achieved by the formation of collagen fiber bundles oriented parallel to the wound surface at both post-surgery periods. In Group AT the type of healing was characterized by dense connective tissue containing collagen fiber bundles arranged amidst the remaining adipose tissue, with rare heterotopic bone formation associated with fibrosis and different types of tissue necrosis. Immunostaining of PPAR-γ was not observed in any specimen from Groups C and AB. In Group AT, the immunostaining of PPAR-γ was more evident 30 days after surgery. Immunostaining of osteocalcin was present in all groups and at both postoperative periods. The fragmented autogenous abdominal adipose tissue graft did not favor the repair of critical-size bone defects created surgically in rat calvaria as evidenced by the positive immunostaining of PPAR-γ protein and the negative immunostaining of osteocalcin in the osteoblast-like cells and bone matrix.

A imunoexpressão das proteínas PPAR-γ e osteocalcina foi avaliada para o reparo ósseo de defeitos de tamanho crítico (DTC) criados em calvária de ratos (n = 42) e tratados com enxerto de tecido adiposo autógeno abdominal macerado. Foram formados três grupos (n=14): C (controlo - coágulo de sangue), AB (osso autógeno) e AT (tecido adiposo fragmentado). Estes grupos foram divididos em subgrupos (n = 7) para a eutanásia em 30 e 90 dias. Foram realizadas análises histológicas e imuno-histoquímico. Os dados foram submetidos à análise estatística descritiva (moda). Um fechamento ósseo completo foi observada no grupo AB 90 dias após a cirurgia. No grupo C a reparação foi alcançada através da formação de feixes de fibras de colágeno orientadas paralelamente à superfície da ferida nos dois períodos pós-operatórios. No Grupo AT, o tipo de cicatrização predominante foi caracterizada pela presença de tecido conjuntivo denso contendo feixes de colágeno de fibras dispostas em meio ao tecido adiposo restante, com raras formações ósseas heterotópicas associada à fibrose e diferentes tipos de necrose tecidual. A imunomarcação do PPAR- γ não foi observada em nenhum espécime dos grupos C e AB. No grupo AT a imunomarcação do PPAR-γ foi mais evidente aos 30 dias de pós-operátorio. A imunomarcação da osteocalcina estava presente em todos os grupos e nos dois períodos de pós-operatório O enxerto autógeno abdominal fragmentado tecido adiposo não favoreceu a reparação de defeitos ósseos de tamanho crítico criados cirurgicamente em calvária de ratos como evidenciado pela imunomarcação positiva da proteína PPAR-γ e a imunomarcação negativa de osteocalcina nos osteoblastos e matriz óssea.

Immunoexpression of BMP-2 protein on bone repair of critical size defects treated with autogenous macerated adipose tissue

Introduction: The adipose tissue is an important reservoir of adult stem cells which have capacity of differentiating in osteoblasts with potential implication in reaching bone regeneration. The evaluation of the osteoblastic differentiation can be verified through immunohistochemical markers such as bone morphogenetic protein- 2 (BMP-2). Objective: To evaluate the immunoexpression of BMP-2 protein on the bone repairing of critical size defects (CSD) surgically created in rat calvaria and treated by autogenous macerated adipose tissue. Material and methods: Forty male rats had a CSD measuring 5 mm created on their calvaria. The animals were randomly divided into two groups: group C (control) and group AT (macerated adipose tissue grafting). In group C, the defect was filled with only blood clot. In group AT, the defect was filled with autogenous macerated adipose tissue. The groups were subdivided into two subgroups (n = 10) for euthanasia at 7 and 90 post-operative days. Histological and immunohistochemical analyses were carried out. Data were submitted to descriptive statistics (mode). Results: In group AT, both at 7 and 90 post-operative days, the main healing type was the presence of dense conjunctive tissue exhibiting bundles of collagen fibers disposed in beams permeating the remaining adipose tissue with rare heterotopic bone formation associated to fibrosis and different types of tissue necrosis. In group C, the repair was achieved by the formation of bundles of collagen fibers oriented parallelly to the surface of the wound at the two post-surgical periods. The immune-staining of BMP-2 was present only in group C (7 and 90 post-operative days). Conclusion: Within the limits of this present study, it can be concluded that the adipose tissue grafting did not favor bone neoformation in critical size defects and BMP-2 signaling was not observed.