3D Bioprinting Techniques and Bioinks for Periodontal Tissues Regeneration-A Literature Review.

The periodontal tissue is made up of supporting tissues and among its functions, it promotes viscoelastic properties, proprioceptive sensors, and dental anchorage. Its progressive destruction by disease leads to the loss of bone and periodontal ligaments. For this reason, biomaterials are constantly being developed to restore tissue function. Various techniques are being used to promote regenerative dentistry, including 3D bioprinting with bioink formulations. This paper aims to review the different types of bioink formulations and 3D bioprinting techniques used in periodontal tissue regeneration. Different techniques have been formulated, and the addition of different materials into bioinks has been conducted, with the intention of improving the process and creating a bioink that supports cell viability, proliferation, differentiation, and stability for periodontal tissue regeneration.

Carbon fiber felt scaffold from Brazilian textile PAN fiber for regeneration of critical size bone defects in rats: A histomorphometric and microCT study.

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty-four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty-four animals were randomly divided into four groups: control (C)-bone defect + blood clot, non-activated carbon fiber felt (NACFF)-bone defect + NACFF, activated carbon fiber felt (ACFF)-bone defect + ACFF, and silver activated carbon fiber felt (Ag-ACFF)-bone defect + Ag-ACFF, and was observed by 15 and 60 days for histomorphometric, three-dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration.

Carbon fiber: Characterization and evaluation of the inflammatory response and toxicity in rats.

This study aimed to evaluate the Carbon Fiber obtained from PAN textile and cotton fiber in their different forms of presentation: non-activated carbon fiber felt (NACFF), activated carbon fiber felt (ACFF), silver activated carbon fiber felt (Ag-ACFF), and activated carbon fiber tissue (ACFT), to obtain scaffolds as a potential material with properties related to the synthetic bone graft. Characterization tests performed: surface wettability, traction, swelling, and in vivo tests: evaluation of the inflammatory response by implanting the materials in the subcutaneous tissue of 14 Wistar rats, evaluation of collagen fibers by picrosirius red staining and assessment of toxicity in the following organs: heart, spleen, liver, and kidney. In the wettability test, NACFF and ACFT were hydrophobic (θ124° and 114°), ACFF and Ag-ACFF were hydrophilic. For maximum stress, ACFF was more resistant (2.983 ± 1.059) p < .05. In the swelling test, the Ag-ACFF and ACFF groups showed the highest absorption percentage for the PBS solution and distilled water (p < .001). The organs showed no signs of acute systemic toxicity. The implant regions showed mild to moderate inflammatory infiltrate at 7 and 21 days. Only the ACFT group did not show the maturation of type I collagen fibers in 21 days. Through the conducted analyses, the ACFT shows little potential to be indicated as a possible scaffold. Therefore NACFF, ACFF, and Ag-ACFF have the potential to be considered scaffolds due to the following characteristics presented: good absorption rate, hydrophilicity, and non-toxic.

Effect of the pulsed electromagnetic field in the repair of a calvaria critical bone defect in rats: cone beam computed tomographic and histomorphometric analysis.: PEMF in the repair of a calvaria critical bone defect: CBCT analyses.

INTRODUCTION: The present study evaluated the effect of two protocols of Pulsed Electromagnetic Field (PEMF) therapy on bone neoformation on calvaria critical defects in rats. MATERIAL & METHODS: 96 rats were randomly divided into 3 groups: Control Group (CG; n=32); Test Group - PEMF 1 hour (TG1h; n=32) and Test Group - PEMF 3 hour (TG3h; n=32). A Critical-size Bone Defect (CSD) was surgically created in the calvaria of rats. The animals in the test groups were exposure to PEMF for 5 days a week. The animals were euthanized at 14, 21, 45 and 60 days. The specimens were processed for volume and texture (TAn) analysis, by Cone Beam Computed Tomography (CBCT) and histomorphometric analysis, RESULTS: Histomorphometric and volume analyses revealed that there was no statistically significant difference in the repair of bone defects between groups receiving PEMF therapy and CG. TAn revealed a statistically significant difference between the groups only for the entropy parameter, in which TG1h group presented a higher value compared to CG on 21 days. TG1h and TG3h did not accelerate bone repair in calvarial critical size defect and the parameters of PEMF should be considered. DISCUSSION: This study showed that PEMF application on CSD in rats does not accelerate bone repair. Although literature showed a positive association in biostimulation on bone tissue with the parameters applied, studies with other PEMF parameters are essential to verify improving this study design.

Systemic scleroderma: imaging findings of diagnosis and clinical management of temporomandibular joint disorders / Esclerodermia sistêmica: diagnóstico por achados imaginológicos e manejo clínico das disfunções temporomandibulares

Scleroderma, an autoimmune disease, directly affects the production of collagen in the connective tissue. In its systemic form, the disease causes oral manifestations such as: limited mouth opening, xerostomia, periodontal disease, thickening of the periodontal ligament and bone resorption of the mandible. This case report aims to draw attention to the difficulties encountered in providing dental care to patients with scleroderma and also to highlight the imaging findings, with emphasis on the temporomandibular joints, which are of interest to dentists about the disease. In the present case, the patient presented bilateral condylar erosion, in addition to disc displacement without reduction. Due to the systemic condition of the patient, it was decided to make an individualized occlusal splint. The limitation of mouth opening is a limiting factor for the manufacture of prostheses and plates, which is why partial prostheses are indicated and are easily removed by the patient. The decisions taken have a great impact on the health and quality of life of patients in these conditions, so there is a need for multidisciplinary involvement in order to arrive at the best treatment plan. After five years of using the stabilizing plate overnight, the patient reports greater comfort and muscle relaxation upon waking up (AU)

Esclerodermia, uma doença autoimune, afeta diretamente a produção de colágeno do tecido conjuntivo. Na forma sistêmica, a doença causa manifestações bucais, como: limitação de abertura bucal, xerostomia, doença periodontal, espessamento do ligamento periodontal e reabsorção da mandíbula. Este relato de caso tem por objetivo chamar atenção para as dificuldades encontradas ao promover atendimento odontológico para pacientes com esclerodermia e também destacar os achados imaginológicos, com ênfase na articulação temporomandibular, que são da doença e de interessa ao cirurgião-dentista. No presente caso, a paciente apresentava erosão condilar bilateral, com deslocamento de disco sem redução. Devido à condição sistêmica da paciente, foi decidido confeccionar uma placa oclusal individualizada. A limitação de abertura bucal é um fator limitante para confecção de próteses e placas, por isso próteses parciais são indicadas, além de serem de fácil remoção pelo paciente. As decisões tomadas tem grande impacto na saúde e qualidade de vida de pacientes nessas condições, deste modo é necessário uma equipe multidisciplinar envolvidas para chegar no melhor plano de tratamento. Após cinco anos fazendo uso da placa estabilizadora durante a noite, a paciente relata maior conforto e relaxamento muscular ao acordar (AU)

Effect of Photobiomodulation Therapy Associated With Biphasic Phosphate Calcium on Bone Repair: A Histomorphometric Study in Rats.

Introduction: This study aimed to investigate the effects of photobiomodulation (PBM) therapy associated with biphasic calcium phosphate on calvaria critical defects in rats. Methods: Forty-eight (90 days old) adult male rats (Rattus norvegicus, Albinus variation, Wistar) received critical defects of 5 mm in diameter, which were made on their skull, and they were randomly assigned into the following groups: C-blood clot, B-biphasic calcium phosphate, L-photobiomodulation therapy, and B + L-biphasic calcium phosphate + photobiomodulation therapy. A low-level a gallium aluminum arsenide (GaAlAs) laser was applied in a single dose during surgery, in a wavelength of 660 nm and total energy density of 45 J/cm2. On 30th and 60th days, the animals from each group were euthanized. Histological and histomorphometric analyses were performed. Results:In 30 days, almost all specimens (C, L, B and B + L) showed bone neoformation areas in regions near the borders of the surgical defect. In 60 days, in many specimens (C, L, B, B + L), it was possible to see a narrow neoformed bone structure along almost the whole extension of the surgical defect, though it was thinner than the original calvary bone. Data were recorded as mean ± standard deviation, and after normality was tested, a suitable statistical test was applied (α = 5%). On day 60, there was a statistically significant difference when comparing the proportion of neoformation area between group L (0.52%±0.13) and group B+L (0.20%±0.08). Group L showed a difference compared with all the groups when we compared the remaining distance between the edges of neoformed bone (C×L, P=0.0431; B × L, P=0.0386; L×B+L, P=0.0352), demonstrating a great defect closure. Conclusion: Our findings suggest that although biphasic calcium phosphate exerts some osteogenic activity during bone repair, PBM therapy is not able to modulate this process.

Comparison of two types of xenogeneic matrices to treat single gingival recessions: A randomized clinical trial.

BACKGROUND: Xenogeneic matrices (XMs) have been increasingly used for root coverage procedures. This study compared the use of two types of XM (collagen matrix [CM] and xenogeneic acellular dermal matrix [XDM]) associated with the coronally advanced flap technique (CAF) to treat single gingival recessions. METHODS: Seventy-five patients presenting single RT1 gingival recession were treated by CAF (control group, n = 25), CAF+CM (test group 1, n = 25), or CAF+XDM (test group 2, n = 25) and completed 6-month follow-up. Clinical, patient-centered, and esthetic assessments were performed and intra- and intergroup differences were analyzed. RESULTS: At 6 months, the mean recession reduction for CAF, CAF+CM, and CAF+XDM was 2.4 ± 0.8 mm, 2.4 ± 0.9 mm and 2.1 ± 0.8 mm, respectively (P > 0.05). The corresponding mean percentage of root coverage was 78.9% ± 26.2% for CAF, 78.0% ± 28.5% for CAF+CM, and 65.6% ± 26.9% for CAF+XDM (P > 0.05). Dentin hypersensitivity and esthetic conditions showed significantly improvements in all groups. Test groups presented significant gains in gingival thickness (GT; CAF+CM: 0.4 ± 0.3 mm; CAF+XDM: 0.4 ± 0.2 mm) compared to the control group (CAF: 0.0 ± 0.1 mm; P < 0.05). CONCLUSION: The CAF, CAF+CM, and CAF+XDM treatments each provided similar results in the treatment of single gingival recessions. The addition of either CM or XDM to CAF increases the GT.

Bone repair assessment of critical size defects in rats treated with mineralized bovine bone (Bio-Oss®) and photobiomodulation therapy: a histomorphometric and immunohistochemical study.

This study aimed to investigate the effects of administering photobiomodulation therapy (PBM) with bovine bone matrix on critical size defects in rats. Seventy-two adult male rats (albinus, Wistar), 90 days old, were used. Defect of 5 mm in diameter was made in their calvaria. The animals were divided into 4 groups: C-blood clot, B-Bio-Oss®, L-PBM, B+L-Bio-Oss®+PBM. Each group has been subdivided into 07, 30, and 60 days of observation. For PBM, a low GaAlAs energy of 660 nm was irradiated, total energy density of 45 J/cm2 . PBM was conducted in a trans-surgical form once only. For immunohistochemistry, a semi-quantitative analysis was made of expression of osteoprotegerin (OPG), nuclear kappa B-factor ligand receptor activator (RANKL), and tartrate-resistant acid phosphatase (TRAP). All histomorphometric data were statistically analyzed by ANOVA and Tukey test, significance level of 5%. The groups that showed the highest proportion of neoformation were L (0.39% ± 0.13) and C (0.37% ± 0.97), but groups B and B+L had larger defect size (C-1.75 mm2 ± 0.40, B-3.02 mm2 ± 0.63, L-2.45 mm2 ± 0.53, B+L-3.23 mm2 ± 1.01). In immunohistochemistry, groups B and B+L had higher immunostaining scores for OPG and RANKL at 60 days, and TRAP immunostaining increased in all groups at 30 days, but group L was the only one to present specimens with score 0. Although, at 60 days, groups L and C presented the highest proportion of bone neoformation, at 30 days group B+L had more than twice as much bone neoformation as group B, the choice of treatment application should depend on the aim of the treatment.

The Effect of Photobiomodulation Therapy in Different Doses on Bone Repair of Critical Size Defects in Rats: A Histomorphometric Study.

Introduction: Photobiomodulation therapy (PBM) appears to induce osteogenesis and stimulate fracture repair; because of its capacity, it is considered a promising treatment, but the characteristics of response to different radiation doses must be investigated through in vivo studies to establish their safety and effectiveness. Thus, this paper aims to analyze the effects of the PBM at different doses on the repair of critical bone defects through histological and histomorphometric analyses. Methods: Sixty 90-day-old adult rats (Rattus norvegicus, albinus, Wistar) weighing approximately 300 g were used. Critical bone defects of 5 mm in diameter were performed in their calvaria. The animals were randomly separated into 5 groups: C-Blood clot, L15-PBM 15J/cm2, L30-PBM 30 J/ cm2, L45-PBM 45 J/cm2, L60-PBM 60 J/cm2. Each group was subdivided according to observation periods of 30 and 60 days with 6 rats in each subgroup. Low-level gallium aluminum arsenide (GaAlAs) lasers were used at a 660 nm wavelength, 30 mW and 0.04 cm2 in area. The PBM was applied over 5 points; 4 points of application were distributed on the edges while one point of application was located in the center of the bone defect. PBM occurred right after the procedure. In 30 and 60 days, the animals were euthanized by anesthesia overdose and the analyses were performed. The data were analyzed statistically by the ANOVA, together with the Tukey test, whose significance level was 5%. Results: As regards the treatment factor, the highest percentage of bone neoformation was achieved by group L45-60. The group with the highest closure, despite not having a statistically significant difference with the other doses, was 45 J with only 0.49 mm between edges. Conclusion: Thus, the present study allowed concluding that the highest percentage of bone neoformation area was achieved at 45 J/cm2 in 60 days; that is, it was significantly effective in comparison with other doses.

Microcurrent electrotherapy improves palatal wound healing: Randomized clinical trial.

BACKGROUND: This study was conducted to assess the clinical, immunological, and patient-centered outcomes of microcurrent electrotherapy on palatal wound healing. METHODS: This was a parallel, double-masked randomized clinical trial, in which 53 patients with ridge preservation indications were selected and randomly assigned to one of two groups. In the control (sham) group (n = 27), palatal wounds, after free gingival grafts (FGG) harvest, received sham application of electrotherapy. In the test (electrotherapy treatment [EE]) group (n = 26), palatal wounds, after FGG harvest, received application of microcurrent electrotherapy protocol. Clinical parameters, patient-centered outcomes, and inflammatory markers were evaluated, up to 90 days postoperatively. RESULTS: The EE group achieved earlier wound closure (P <0.001) and epithelialization (P <0.05; P = 0.03) at 7 and 14 days after harvest when compared with the sham group. Painful symptomatology was reported less frequently in the EE group than in the sham group at 3-day follow-up (P = 0.008). Likewise, an improvement in Oral Health Impact Profile was reported 2 days after the procedure by the EE group (P = 0.04). In addition, favorable modulation of inflammatory wound healing markers occurred when electrotherapy was applied. CONCLUSION: Within the limits of the present study, it can be concluded that the use of a low-intensity electrotherapy protocol may accelerate palatal wound healing and decrease patient discomfort after FGG harvest.

Influence of Cigarette Smoke Inhalation on an Autogenous Onlay Bone Graft Area in Rats with Estrogen Deficiency: A Histomorphometric and Immunohistochemistry Study.

PURPOSE: The present study aimed to evaluate the influence of cigarette smoke inhalation on an autogenous onlay bone graft area, either covered with a collagen membrane or not, in healthy and estrogen-deficient rats through histomorphometry and immunohistochemistry. MATERIALS AND METHODS: Sixty female rats (Wistar), weighing 250-300 g, were randomly divided and allocated into groups (either exposed to cigarette smoke inhalation or not, ovariectomized and SHAM). After 15 days, the test group underwent cigarette smoke inhalation. Sixty days after exposition, autogenous bone grafting was only performed on all right hemimandibles, and the left ones underwent autogenous onlay bone grafting with the collagen membrane (BioGide®). The graft was harvested from the parietal bone and attached to the animals' jaws (right and left). They were euthanized at 21, 45, and 60 days after grafting. Histological measurements and immunohistochemical analyses were performed, and results were submitted to a statistical analysis. RESULTS: The addition of a collagen membrane to the bone graft proved more efficient in preserving graft area if compared to the graft area without a collagen membrane and the one associated with cigarette smoke inhalation at 21 (p = 0.0381) and 60 days (p = 0.0192), respectively. Cigarette smoke inhalation combined with ovariectomy promoted a significant reduction of the autogenous graft area at 21 and 60 days. At 45 days, no statistically significant results were observed. In the immunohistochemical analysis, the ovariectomized and smoking subgroups, combined or not with collagen membrane, received moderate and intense immunolabeling at 21 days for Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL) (p = 0.0017 and p = 0.0381, respectively). For Osteoprotegerin (OPG), intense immunolabeling was observed in most subgroups under analysis at 60 days. CONCLUSION: Smoking inhalation promoted resorption on the autogenous onlay bone graft, mainly when associated with ovariectomy. Furthermore, when associated with the collagen membrane, a lower resorption rate was observed if compared to the absence of the membrane.

Evaluation of the local effect of nonsurgical periodontal treatment with and without systemic antibiotic and photodynamic therapy in generalized aggressive periodontitis. A randomized clinical trial.

BACKGROUND: This study's aim was to evaluate the local effect of clarithromycin associated with antimicrobial photodynamic therapy (aPDT) in the treatment of generalized aggressive periodontitis. MATERIALS AND METHODS: The study sample comprised 72 periodontal pockets on single-rooted teeth in multiple quadrants, with both probing depth and clinical attachment level ≥5 mm, and with bleeding on probing. The pockets were randomly distributed into four groups (n = 18 each) that received ultrasonic periodontal debridement in addition to placebo (the UPD group), systemic clarithromycin (the UPD + CLM group), aPDT (the UPD + aPDT group), or both systemic clarithromycin and aPDT (the UPD + CLM + aPDT group). The measurements were performed prior to treatment (baseline) and at 3 and 6 months postoperatively. The following parameters were evaluated: plaque index, bleeding on probing, probing depth, gingival recession, and clinical attachment level. A 5% significance level was used in the statistical analysis. RESULTS: At 3 months, UPD + aPDT, UPD + CLM, and UPD + CLM + aPDT groups all exhibited reduced probing depths relative to the UPD group (p < 0.05). However, at 6 months, the reduction in mean probing depth was greater in the antibiotic groups (UPD+CLM and UPD+CLM+aPDT) than in the UPD and UPD+aPDT groups (p < 0.05). Regarding clinical attachment level, only the UPD+CLM+aPDT group presented a significant gain relative to the UPD and UPD + PDT groups (p < 0.05). CONCLUSIONS: Ultrasonic periodontal debridement has greater clinical advantages when associated with clarithromycin than with associated with aPDT. However, the joint application of aPDT and clarithromycin did not present additional benefits.

Periodontal response to orthodontic tooth movement in diabetes-induced rats with or without periodontal disease.

BACKGROUND: Systemic conditions can influence orthodontic tooth movement. This study evaluates histologic periodontal responses to orthodontic tooth movement in diabetes-induced rats with or without periodontal disease. METHODS: Forty Wistar rats were divided according their systemic condition (SC) into diabetic (D) and non-diabetic (ND) groups. Each group was subdivided into control (C), orthodontic tooth movement (OM), ligature-induced periodontitis (P) and ligature-induced periodontitis with orthodontic movement (P+OM) groups. Diabetes mellitus (DM) was induced with alloxan monohydrate, and after 30 days, the P group received a cotton ligature around their first lower molar crown. An orthodontic device was placed in OM and P+OM groups for 7 days, and the animals were then euthanized. RESULTS: Differences in OM between D and ND groups were not significant (6.87± 3.55 mm and 6.81 ± 3.28 mm, respectively), but intragroup analysis revealed statistically significant differences between the P+OM groups for both SCs. Bone loss was greater in the D group (0.16 ± 0.07 mm2 ) than in the ND group (0.10 ± 0.03 mm2 ). In intragroup analysis of the D condition, the P+OM group differed statistically from the other groups, while in the ND condition, the P+OM group was different from the C and OM groups. There was a statistically significant difference in bone density between D and ND conditions (18.03 ± 8.09% and 22.53 ± 7.72%) in the C, P, and P+OM groups. CONCLUSION: DM has deleterious effects on bone density and bone loss in the furcation region. These effects are maximized when associated with ligature-induced periodontitis with orthodontic movement.

Local adjunct effect of antimicrobial photodynamic therapy for the treatment of chronic periodontitis in type 2 diabetics: split-mouth double-blind randomized controlled clinical trial.

Diabetes has become a global epidemic. Its complications can have a significant impact on quality of life, longevity, and public health costs. The presence of diabetes might impair the prognosis of periodontal treatments due to its negative influence on wound healing. Antimicrobial photodynamic therapy (aPDT) is a local approach that can promote bacterial decontamination in periodontal pockets. The aim of this study was to investigate the local effect of adjunct aPDT to ultrasonic periodontal debridement (UPD) and compare it to UD only for the treatment of chronic periodontitis in type 2 diabetic patients. Twenty type 2 diabetic patients with moderate to severe generalized chronic periodontitis were selected. Two periodontal pockets with probing depth (PD) and clinical attachment level (CAL) ≥5 mm received UPD only (UPD group) or UPD plus adjunct aPDT (UPD + aPDT group). Periodontal clinical measures were collected and compared at baseline and 30, 90, and 180 days. After 180 days of follow-up, there were statistically significant reductions in PD from 5.75 ± 0.91 to 3.47 ± 0.97 mm in the UPD group and from 6.15 ± 1.27 to 3.71 ± 1.63 mm in the UPD + aPDT group. However, intergroup analysis did not reveal statistically significant differences in any of the evaluated clinical parameters (p > 0.05). The adjunct application of aPDT to UPD did not present additional benefits for the treatment of chronic periodontitis in type 2 diabetic patients. The ClinicalTrials.gov identifier of the present study is NCT02627534.

Comparison of two power densities on the healing of palatal wounds after connective tissue graft removal: randomized clinical trial.

UNLABELLED: Connective tissue graft (CTG), which is considered to be among the best techniques for treating gingival recession, has presented stable long-term results. However, this technique causes morbidity and discomfort in the palatine region due to graft removal at that site. A previous study reports that photobiomodulation (PBM) using a dosage of 15 J/cm(2) may improve wound healing and the patient's postoperative comfort. However, no other studies in the literature provide the best application dosage or comparisons between protocols for this purpose. The aim of this study is to compare two power densities of PBM on the wound-healing process of the donor palatine area after CTG removal. In this study, 51 patients presenting buccal gingival recession were randomized into one of the following groups: group 1: CTG procedure for root coverage and PBM application at the donor site using a 60 J/cm(2) dose; group 2: CTG and PBM application using a 30 J/cm(2) dose; or group 3: CTG and sham application. The evaluated parameters were the wound remaining area (WRA), scar and tissue colorimetry (TC), tissue thickness (TT), and postoperative discomfort (D), evaluated at baseline and 7, 14, 45, 60, and 90 days after surgery. Group 1 presented statistically significant smaller wounds at day 7 (p > 0.05). None of the patients presented scars at the operated area, and all of the patients reported mild discomfort, with low consumption of analgesic pills. We concluded that the protocol of 60 J/cm(2) provided faster wound healing 7 days after removing the connective tissue graft for root coverage. TRIAL REGISTRATION: ClinicalTrial.org (NCT02580357) https://clinicaltrials.gov/ct2/show/NCT02580357 .

Osteoclacin expression during autogenous onlay bone grafts with or without resorbable collagen membrane in diabetic rats / Expressão da osteocalcina no reparo de enxertos ósseos autógenos onlay recobertos ou não por membrana colágena reabsorvível em ratos diabéticos

Objetivo: O objetivo deste estudo foi quantificar, através da técnica imunoistoquímica, a expressão do marcador de formação óssea Osteocalcina no processo de reparo do enxerto ósseo autógeno onlay, associado ou não à membrana colágena reabsorvível e comparar esses achados com a presença da Diabetes Mellitus. Material e Métodos: Foram utilizados 60 ratos (Rattus norvegicus, variação albinus, Wistar) com 90 dias de idade, divididos em dois grupos , cada um contendo 30 animais: Grupo Teste com Diabéticos , composto por ratos com diabetes induzida e Grupo Controle composto por ratos normoglicêmicos. Todos receberam enxertos na hemi mandíbula esquerda com recobrimento de membrana colágena e na hemi mandíbula direita sem recobrimento. Os animais foram eutanasiados nos períodos 0h, 7, 14, 21, 45 e 60 dias. A análise imunoistoquímica foi realizada com o marcador Osteocalcina na interface leito-enxerto. Para analise da expressão imunoistoquímica da Osteocalcina, realizou-se uma fotografia com visão panorâmica do enxerto e duas fotografias em maior aumento. Resultados: Os resultados mostraram que houve diferença estatisticamente significante ao nível de 5% intragrupo para Diabético e Controle com e sem membrana e também quando comparamos o grupo Diabético com o Controle com a presença da membrana. Conclusão: Dentro dos limites do presente estudo, pode-se concluir que a marcação da osteocalcina pode sofrer alguma influência do diabetes, sendo expressa de forma mais tardia na presença dessa condição. Porém, a associação da membrana ao enxerto pode melhorar esse atraso e deixar a expressão semelhante ao grupo controle.

Objective: This study aimed to quantify through immunohistochemistry the expression of bone formation marker osteocalcin during the repair process of autogenous onlay bone graft, associated or not to the resorbable collagen membrane and to compare these findings with the presence of Diabetes Mellitus. Material and Methods: Sixty rats (Rattus norvegicus, albinus variation, Wistar) aged 90 days, were divided into two groups with 30 animals: test group – rats with induced diabetes; control group - normoglycemic rats. All rats received grafts on the left and right hemi-mandible with or without collagen membrane coverage, respectively. The animals were euthanized at the following periods: 0h, 7, 14, 21, 45, and 60 days. Immunohistochemistry analysis was performed by the marker osteocalcin at receptor site-graft interface. To analyze osteocalcin immunohistochemical expression, a panoramic view photograph of the graft was taken followed by two photographs at larger magnification. Results: No statistically significances at 5% level were observed between diabetic and control group with and without membrane; and diabetic and control groups with membrane coverage. Conclusion: Within the limits of this present study, it can be concluded that the osteocalcin marker might be influenced by diabetes so that it was late expressed during this condition. However, the association of the graft with the membrane could improve this delay by reaching expression values similar to those of control group.

The RANK/ RANKL/ OPG interaction in the repair of autogenous bone grafts in female rats with estrogen deficiency.

The aim of this study was to evaluate the resorption process during the repair of autogenous bone grafts with or without coverage by an expanded polytetrafluoroethylene (e-PTFE) membrane in female rats with estrogen deficiency using the immunohistochemical technique. Eighty female rats were randomly divided into two groups (OVX and SHAM). The 40 female rats in the OVX group were subjected to ovariectomy, and the 40 female rats in the SHAM group were subjected to simulated ovariectomy. The two groups were further divided in subgroup E, which was subjected to surgery for placement of autogenous bone graft (ABG), and subgroup ME, in which the ABG was covered with an e-PTFE membrane. The animals were killed at 0, 7, 21, 45 and 60 days. The specimens were analyzed using immunohistochemistry for the bone resorption markers RANK, RANK-L and Osteoprotegerin (OPG). A higher remodeling rate was observed at 7 and 21 days after the autogenous bone grafts, when the markers were more intensely expressed. At the final time point, the specimens presented similar characteristics to those observed at the initial time point. The expression of immunohistochemical markers was not altered by the estrogen deficiency. The presence of the e-PTFE membrane delayed the bone resorption process, influencing the immunohistochemical expression of markers.

Oral condition of critical patients and its correlation with ventilator-associated pneumonia: a pilot study / Condição oral de pacientes críticos e sua correlação com pneumonia associada a ventilação mecânica: um estudo piloto

Introduction: Literature has reported inadequate oral hygiene conditions in Intensive Care Unit (ICU) patients and the occurrence of Ventilator-associated pneumonia in about 9%-27% of all intubated patients. Objective: The aim of this study was to evaluate ICU patient's oral conditions and correlate this with the presence of ventilator-associated pneumonia. Material and Method: Twenty-three patients were categorized in the following way: with periodontal disease and ventilator-associated pneumonia, with periodontal disease and without ventilator-associated pneumonia, without periodontal disease and with ventilator-associated pneumonia, and with neither periodontal disease nor ventilator-associated pneumonia. The periodontal disease index, plaque index, and decay-missing-filled index were used in the assessment. Result: There was no statistically significant difference in the incidence of periodontal disease with respect to ventilator-associated pneumonia, but the number of teeth and surfaces with attachment loss above 4 mm was always greater in patients with ventilator-associated pneumonia. Conclusion: The extent of periodontal disease may contribute to the onset of ventilator-associated pneumonia. However, studies with a larger sample are needed to validate this relationship.

Introdução: A literatura vem relatando condições inadequadas de higiene oral de pacientes em unidade de terapia intensiva (UTI) e a ocorrência de Pneumonia associada à ventilação mecânica em cerca de 9%-27% de todos os pacientes intubados. Objetivo: O objetivo deste estudo foi avaliar condições orais de pacientes críticos e correlacionar com a presença de pneumonia associada à ventilação mecânica. Material e Método: Vinte e três pacientes foram categorizados da seguinte maneira: com a doença periodontal e com pneumonia associada à ventilação mecânica, com doença periodontal e sem pneumonia associada à ventilação mecânica, sem doença periodontal e com pneumonia associada à ventilação mecânica e sem doença periodontal e sem pneumonia associada à ventilação mecânica. Foram utilizados na avaliação os índices de placa, de doença periodontal e índice de cariados, perdidos e obturados. Resultado: Não houve diferença estatisticamente significante na incidência da doença periodontal em relação à pneumonia associada à ventilação mecânica, mas o número de dentes e superfícies com perda de inserção acima de 4 mm sempre foi maior em pacientes com pneumonia associada à ventilação mecânica. Conclusão: A extensão da doença periodontal pode contribuir para o aparecimento de pneumonia associada à ventilação mecânica. No entanto, são necessários estudos com uma amostra maior para validar essa relação.

Evaluation of dental staining using a dentifrice containing chlorhexidine and zinc acetate. A doble blind randomizedclinical trial / Avaliação de dentifrício contendo clorexidina e acetato de zinco. Estudo clínico controlado randomizado duplo cego

Objective: The aim of this study was to evaluate whether the association of chlorhexidine with zinc acetate in dentifrices formulations could reduce the emergence of extrinsic tooth stain. As second outcome check the clinical gingival parameters. Methods: 30 volunteers were randomly divided into three groups: CHX+Z, consisting of 10 participants who used a dentifrice with 0.8% chlorhexidine gluconate and zinc acetate 1.16%; CHX group, with 10 participants who used a similar formulation dentifrice without zinc acetate, and the Placebo group also with 10 participants who used a dentifrice formulation similar but without the chlorhexidine and zinc acetate. Patients were assessed at baseline and 60 days when the indexes of plaque, gingival bleeding and staining were collected. Results: The results showed that by day 60, there was a decrease of both plaque index(PI) and the gingival index(GI) for all groups. Additionally, it was observed that both groups using dentifrice containing chlorhexidine, showed more stain than placebo. The CHX+Z group showed less stain compared to the CHX group, but the difference was not statistically significant. The difference between Placebo and Chlorhexidine Groups was statistically significant (p < 0.05) when considered the stain intensity and area plus intensity scores. The CHX+Z group was as efficient in PI and GI reduction as the CHX group. Conclusions: The association of chlorhexidine with zinc acetate showed no additional benefits regarding reducing the staining. The dentifrices containing chlorhexidine presented higher reduction of GI and PI when compared to Placebo group.

Objetivo: O objetivo deste estudo foi avaliar se a associação de clorexidina com acetato de zinco em dentifrícios poderia reduzir o aparecimento de manchas dentárias extrínsecas. Como segundo objetivo verificar os parâmetros clínicos gengivais. Materiais e métodos: 30 voluntários foram divididos aleatoriamente em três grupos: CHX + Z, composta por 10 participantes que usaram um creme dental com 0,8% de gluconato de clorexidina e acetato de zinco 1,16%; grupo CHX, com 10 participantes que usaram uma formulação de dentifrício semelhante, porém sem acetato de zinco, e o grupo do placebo também com 10 participantes que usaram uma formulação dentífrica semelhante, mas sem a clorexidina e sem acetato de zinco. Os pacientes foram avaliados no início do estudo e após 60 dias, quando foram coletados os índices de placa, sangramento gengival e manchas. Resultados: Os resultados revelaram que ao dia 60, havia uma redução em ambos os índices, de placa (IP) e do índice gengival (IG) em todos os grupos. Além disso, observou-se que em ambos os grupos que utilizou dentifrício contendo clorexidina, mostrou um maior índice de manchas maior do que o placebo. O grupo CHX + Z apresentou um índice de manchas menor em relação ao grupo

Analysis of the volume of autogenous cancellous bone grafts with or without the use of PTFE-e membranes in ovariectomized rats / Análise do volume ósseo trabecular de enxertos ósseos autógenos recobertos ou não por membranas de PTFE-e em ratas ovarectomizadas

Objetivo: Avaliar quantitativamente e descrever qualitativamente o processo de reparação óssea da interface leito receptor e enxerto ósseo autógeno em bloco associado ou não a membrana de PTFE-e, em ratas, portadoras de osteopenia induzida. Material e Metodos: 48 ratas Wistar pesando aproximadamente 300 g, receberam um enxerto ósseo do osso parietal o qual foi fixado à parede lateral do ramo mandibular esquerdo. Os animais foram divididos aleatoriamente em quatro grupos: Grupo 1: ovariectomia simulada (SHAM) e enxerto ósseo autógeno; Grupo 2: SHAM e enxerto ósseo autógeno com recobrimento por membrana de PTFE-e; Grupo 3: ovariectomia (OVZ) e enxerto ósseo autógeno; Grupo 4: OVZ e enxerto ósseo autógeno com recobrimento por membrana de PTFE-e. Os animais de cada grupo foram sacrificados nos períodos: 21, 45 e 60 dias, com 4 animais por grupo. As peças foram descalcificadas e incluídas; os cortes corados com HE e submetidos à análise histológica e histomorfométrica em microscopia de luz. Resultados: Os testes ANOVA mostraram que as variáveis referente a condição (OVZ e SHAM) e ao período (21,45 e 60 dias) foram estatisticamente significantes, pode-se estabelecer com o teste de Tukey (5%) que o período de 21 dias difere estatisticamente dos períodos de 45 e 60 dias, que entre si não diferem. A análise histológica descritiva mostrou integração do enxerto em todos os animais.Conclusão: O processo de integração do enxerto ao leito foi negativamente afetado na presença de osteopenia induzida e o uso ou não da membrana de PTFE-e, não interferiu neste processo de integração

Objective: To verify the influence of the osteopeny induced by the bone repairing of the receptor site/autogenous bone graft block interface either associated with or without PTFE-e membrane through the analysis of the trabecular bone volume. Material & Methods: 48 Wistar rats weighing approximately 300 g were submitted to parietal bone graft which was fixed to the lateral wall of the left mandibular ramus. The animals were randomly divided into four groups: Group 1: simulated ovariotomy (SHAM) and autogenous bone graft; Group 2: SHAM and autogenous bone graft through PTFE-e membrane recovering; Group 3: ovariotomy (OVZ) and autogenous bone graft; Group 4: OVZ and autogenous bone graft and PTFE-e membrane recovering. The animals of each group were killed at the following periods: 21, 45 and 60 days, comprising 4 animals per group. The pieces were decalcified and included; the cuts were stained with HE and submitted to histological and histomorphometric analysis through light microscopy. Results: ANOVA test showed that the variables accounting for both the condition (OVZ and SHAM) and the period (21,45 and 60 days) were statistically significant; the Tukey test (5%) showed that the period of 21 days was statistically different from 45 and 60 days; however, they were not statistically different between each other. The descriptive histological analysis showed grafting integration in all animals. Conclusion: the process of graft integration with the receptor site was negatively affected by the induced osteopeny presence and presence or absence of PTFE-e membrane did not interfered in the integration process.