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1.
Photochem Photobiol Sci ; 23(8): 1565-1571, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39060841

ABSTRACT

The present study aimed to evaluate the effect of photobiomodulation therapy (PBM) on different stages of osteogenesis in vitro. For this, osteoblastic-like cells (Saos-2 cell lineage) were irradiated in two different periods: during the Proliferation phase (PP; from the second to the fourth day) and during the Differentiation phase (DP; from the seventh to the ninth day). The energy density used in the study was 1.5 J/ cm2. The following parameters were evaluated: 1) quantification of collagen type 1 (COL 1), osteopontin (OPN), and bone morphogenetic protein 2 (BMP-2); 2) quantification of alkaline phosphatase (ALP) activity; and 3) quantification of  extracellular matrix (ECM) mineralization. Non-irradiated cultures were used as controls. The data were analyzed using the Student's t-test or one-way ANOVA, considering a significance level of 5%. The results indicated that COL 1 and BMP-2 quantification was higher in Saos-2 irradiated during the DP in relation to the control group at day 10 (p < 0.05). No differences were observed for other comparisons at this time point (p > 0.05). OPN expression was greater in PP compared with the other experimental groups at day 10 (p < 0.05). Irradiation did not affect ALP activity in Saos-2 regardless of the exposure phase and the time point evaluated (p > 0.05). At day 14, ECM mineralization was higher in Saos-2 cultures irradiated during the DP in relation to the PP (p < 0.05). In conclusion, the results suggested that the effects of PBM on osteoblastic cells may be influenced by the stage of cell differentiation.


Subject(s)
Alkaline Phosphatase , Bone Morphogenetic Protein 2 , Cell Differentiation , Cell Proliferation , Collagen Type I , Low-Level Light Therapy , Osteoblasts , Osteogenesis , Osteopontin , Osteogenesis/radiation effects , Humans , Bone Morphogenetic Protein 2/metabolism , Alkaline Phosphatase/metabolism , Osteopontin/metabolism , Cell Differentiation/radiation effects , Collagen Type I/metabolism , Osteoblasts/radiation effects , Osteoblasts/cytology , Osteoblasts/metabolism , Cell Proliferation/radiation effects , Extracellular Matrix/metabolism , Extracellular Matrix/radiation effects
2.
Dent J (Basel) ; 12(6)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38920873

ABSTRACT

The aim of this study is to validate a minimally invasive surgical procedure to harvest palate periosteum as a source of tissue for mesenchymal stromal/stem cells. We performed a standardized procedure to harvest the palate periosteum in ten subjects, which consisted of a 3 mm disposable punch and a Molt periosteal elevator to harvest a small full-thickness fragment of soft tissue at the hard palate area, between the upper bicuspids, 3 to 4 mm apical to the cement enamel junction. The one-third inner portion was fragmented, and following standard cell culture procedures, the adherent cells were cultured for three passages, after obtaining 70-90% confluence. Cell morphology analysis, flow cytometry analysis, and viability and osteogenic differentiation assays were performed. In all 10 cases, uneventful healing was observed, with no need for analgesic intake. The evaluation of cell morphology showed elongated spindle-shaped cells distributed in woven patterns. A high viability range was verified as well as an immunophenotype compatible with mesenchymal stem cell lineage. The differentiation assay showed the potential of the cells to differentiate into the osteogenic lineage. These results demonstrate that the minimally invasive proposed surgical technique is capable of supplying enough periosteum source tissue for stem cell culture and bone tissue engineering.

3.
Postgrad Med ; 136(4): 358-365, 2024 May.
Article in English | MEDLINE | ID: mdl-38795063

ABSTRACT

Hiatal hernia (HH) is a common disease in the general population. It is often asymptomatic, but if it does present clinical manifestations, these are usually gastrointestinal. Gastroesophageal reflux is the main symptom that accompanies it. Depending on the severity of the hernia, it is classified into several subtypes from I-IV. Especially, IV type (giant HH) can lead to various cardiopulmonary symptoms with several degrees of severity. It is necessary to keep this possibility in mind among the various differential diagnoses that may occur in this clinical setting. The current paper aims to review the literature on classic and novel information on the HH - cardiovascular system relationship. Epidemiological data, physiological aspects of the heart compressed by HH, cardiovascular symptoms, electrocardiographic changes, echocardiographic alterations and clinical implications are discussed.


Normally, the stomach and the heart are not in direct contact because they are in different cavities, the thorax and the abdomen, respectively. When part of the stomach moves toward the chest through the diaphragm, we say there is a hiatal hernia (HH). Most of the time the HH symptoms are mild and clearly digestive. In severe cases, surgical repair of the HH is required. Even in these circumstances, digestive symptoms continue to be the most frequent. However, some patients present cardiovascular symptoms and few or no digestive symptoms. This easily creates diagnostic confusion, which leads to incorrect treatments and unnecessary expenses. In extreme cases, as seen in giant HH, the degree of cardiovascular involvement is very serious. There are documented cases that have suffered cardiac arrest, arrhythmias of different types and symptoms like classic acute myocardial infarction. It is required that clinical doctors and surgeons are aware that this complication exists. Only with this in mind can a timely diagnosis be achieved. Some emergency measures have been saving, gastric decompression with a tube being the most important. The main mechanism that explains the serious cardiovascular consequences of giant HH is cardiac compression. The dissemination of this knowledge can help save lives.


Subject(s)
Gastroesophageal Reflux , Hernia, Hiatal , Hernia, Hiatal/complications , Humans , Gastroesophageal Reflux/physiopathology , Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/complications , Electrocardiography/methods , Echocardiography/methods , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Cardiovascular Diseases/physiopathology , Severity of Illness Index
4.
Int Endod J ; 57(6): 700-712, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38404175

ABSTRACT

AIM: To evaluate the influence of different preparation tapers on the reduction in planktonic bacteria and biofilms of Enterococcus faecalis and Candida albicans in the apical third (4 mm) of the mesial roots of mandibular molars, correlating decontamination with canal shape. METHODOLOGY: After microtomography analysis for morphological standardization of the canals, 48 mandibular molar roots, each containing two canals (96 canals), were contaminated with E. faecalis and C. albicans and divided into four groups (n = 11) for canal instrumentation using ProDesign Logic 2 files with different tapers G (.03): # 25.03; G (.04): # 25.04; G (.05): # 25.05; and G (.06): # 25.06 and irrigation with 2.5% sodium hypochlorite. Four roots were examined under a scanning electron microscope (SEM) to qualitatively assess biofilm formation. Eight roots were used as the negative control group (samples were not contaminated). Bacteriological samples were taken exclusively from the apical third of the roots before and after chemical-mechanical preparation and bacterial counts were determined (CFU/mL). The final micro-CT scan was used to quantify the volume variation and unprepared canal area in the apical third. Statistical analysis was performed using the Kruskal-Wallis, Student-Newman-Keuls and Wilcoxon tests for analysis of microbiological data. anova and the Tukey or Games-Howell test were used for analysis of micro-CT data and Spearman's test for correlations (α = 5%). RESULTS: All groups showed a significant reduction in bacteria (p < .05), with no statistically significant difference between groups. There was no significant difference in per cent volume increase between groups. The unprepared area (Δ%) was affected by the file used (p = .026) and was significantly lower for G (.06) compared to G (.03). There was no statistically significant correlation among bacterial reduction, volume and unprepared area (p > .05). CONCLUSION: The different preparation tapers influenced root canal shaping in the apical third but did not improve decontamination in this region.


Subject(s)
Biofilms , Candida albicans , Dental Pulp Cavity , Enterococcus faecalis , Root Canal Preparation , X-Ray Microtomography , X-Ray Microtomography/methods , Humans , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Candida albicans/isolation & purification , Candida albicans/physiology , Dental Pulp Cavity/microbiology , Dental Pulp Cavity/diagnostic imaging , Sodium Hypochlorite/therapeutic use , Sodium Hypochlorite/pharmacology , Microscopy, Electron, Scanning , Molar/microbiology , Plankton , Root Canal Irrigants/administration & dosage , Root Canal Irrigants/therapeutic use , In Vitro Techniques , Tooth Apex/microbiology , Tooth Apex/diagnostic imaging
6.
Acta Odontol Latinoam ; 36(2): 120-127, 2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37776509

ABSTRACT

AIM: This study evaluated cytotoxicity and antioxidant gene expression of resin cements on human gingival fibroblasts (hGF). MATERIALS AND METHOD: RelyX Ultimate™(RXU), Variolink™II(VLII), and RelyXU200™(RXU200) resin cements were incubated with culture medium for 24 h to obtain eluates. Then, the eluates were applied over hGF to assess cell viability at 24 h, 48 h, and 72 h and antioxidant gene expression at 24 h. hGF cultures non-exposed to the eluates were used as Control. Data were submitted to ANOVA and Bonferroni tests (α≤0.05). RESULTS: RXU and RXU200 reduced the number of viable cells in 24 h. Longer exposure to cement extracts caused cell death. Gene expression showed peroxiredoxin 1 (PRDX1) induction by all resin cement types, and superoxide dismutase 1 (SOD1) induction by RXU200 and VLII. Moreover, RXU200 induced not only PRDX1 and SOD1, but also glutathione peroxidase 1 (GPX1), catalase (CAT), and glutathione synthetase (GSS). CONCLUSIONS: All resin cements showed toxicity, and induced antioxidant genes in hGF. Antioxidant gene induction is at least partly associated with cytotoxicity of tested cements to oxidative stress experience.


OBJETIVO: O objetivo deste estudo foi avaliar a toxicidade dos cimentos resinosos Rely X Ultimate 2, Rely X U200 e Variolink II, bem como sua influência na expressão de genes antioxidantes em fibroblastos gengivais humanos. Materiais e Método: Corpos de prova de cada cimento foram colocados em meio de cultura por 24 h e os extratos correspondentes foram aplicados aos fibroblastos. A viabilidade celular foi avaliada após 24, 48 e 72 h de exposição pelo ensaio de exclusão do azul de tripano e MTT. A expressão gênica foi avaliada por PCR quantitativo após 24 h de exposição aos extratos. Estes parâmetros foram comparados aos das células não expostas aos cimentos. Os dados foram submetidos ao teste ANOVA, seguido pelo pós-teste de Bonferroni (a≤0.05). RESULTADOS: Os resultados demonstraram que todos os cimentos promoveram redução do número de células viáveis e da atividade mitocondrial nos períodos de 48 e de 72 h (p< 0,01), sendo que o Variolink II apresentou o menor efeito e os cimentos Rely X Ultimate e Rely X U200 promoveram similarmente os maiores efeitos. A análise de expressão gênica evidenciou influência significativa em todos os cimentos avaliados sobre os níveis de transcritos de PRDX1, SOD1, GPX1 e GSS (p> 0,05), com um aumento considerável no Rely X U200. Conclusão: A indução de genes antioxidantes está, pelo menos em parte, associada à citotoxicidade dos cimentos testados para a experiência de estresse oxidativo.


Subject(s)
Antioxidants , Resin Cements , Humans , Resin Cements/toxicity , Antioxidants/pharmacology , Superoxide Dismutase-1 , Materials Testing , Dental Cements/toxicity
7.
J Stomatol Oral Maxillofac Surg ; 124(6S): 101607, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37582461

ABSTRACT

OBJECTIVE: Guided tissue regeneration (GTR) is based on the use of different membranes that function as sealants and barriers in specific clinical situations. Among the several tissue production methods and origins, resorbable porcine-derived membranes are the most commonly used. Because these membranes are so diverse, and have several different clinical applications, doubts linger as to their effect in stimulating osteogenesis. The objective of this study was to make an in vitro evaluation of the viability and differentiation of osteoblastic cells cultured on the surface of the following collagen membranes: Jason® (Botiss Biomaterials), Collprotect® (Botiss Biomaterials), and Bio-Gide® (Geistlich). MATERIAL AND METHODS: Fragments of the 3 resorbable collagen membranes (5 × 5 mm) were used, and pre-osteoblastic SAOS-2 cells (ATCC, USA) were plated on their porous surfaces. Evaluation of the membranes was performed at 3, 5 and 7 days, considering the following parameters: (1) topographic analysis of the different surfaces by scanning electron microscope; (2) cellular viability by MTT, (3) quantification of type I collagen and osteopontin by Elisa. The quantitative analyses were carried out using a significance level of 5%. RESULTS: Collprotect® and Jason® membranes presented a rough surface with an irregular aspect on both sides, while double-layered Bio-Gide® had one layer with a smooth surface and the other with a rough surface along each respective length. The viability assays revealed that the cells cultured the cells grown on Collprotect® showed higher viability than those grown in Bio-Gide® or Jason®, especially after 5 and 7 days. After 3 and 5 days, evaluation of type I collagen showed that the cells plated on the Jason® and Collprotect® surfaces had greater collagen secretion than those plated on BioGide®. After 7 days, an increase in osteopontin levels was observed when the cells were plated on all the experimental membranes, compared with the control group. CONCLUSION: All the tested membranes were suitable for use in GTR clinical procedures. Their indication in specific regenerative cases depends on the mechanical and biological properties of their originating tissues, thus enabling better results and assertive choices by dental professionals.


Subject(s)
Collagen Type I , Osteogenesis , Humans , Swine , Animals , Osteopontin , Membranes, Artificial , Collagen , Biocompatible Materials , Guided Tissue Regeneration, Periodontal/methods
8.
Arch Oral Biol ; 155: 105778, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37572522

ABSTRACT

OBJECTIVE: Semaphorin 4D (Sema4D) is a coupling factor expressed on osteoclasts that may hinder osteoblast differentiation. Since the leukocyte platelet-rich fibrin (L-PRF) membrane promotes growth factor concentration, this study aims to quantify the amount of Sema4D in L-PRF membranes, and analyze the impact of Sema4D on osteoblast cell function in vitro. DESIGN: Enzyme-linked immunosorbent assay (ELISA) was used to quantify the levels of Sema4D in both L-PRF and whole blood (serum). To analyze the impairment of Sema4D on osteoblasts, MC3T3-E1 cells were induced to osteogenic differentiation and exposed to Sema4D ranging from 10 to 500 ng/ml concentrations. The following parameters were assayed: 1) cell viability by MTT assay after 24, 48, and 72 h; 2) matrix mineralization by Alizarin Red staining after 14 days, 3) Runt-related transcription factor 2 (RUNX-2), osteocalcin (OCN), osteonectin (ONC), bone sialoprotein (BSP) and alkaline phosphatase (ALP) gene expression by qPCR. For all data, the significance level was set at 5%. RESULTS: The amount of Sema4D in the whole blood (serum) was higher than in L-PRF. Osteoblasts exposed to Sema4D at all tested concentrations exhibited a decrease in matrix mineralization formation as well in RUNX-2, OCN, ONC, BSP, and ALP gene expression (p < 0.05). CONCLUSION: The presence of Sema4D, a molecule known for suppressing osteoblast activity, diminishes within L-PRF, enhancing its ability to facilitate bone regeneration.


Subject(s)
Platelet-Rich Fibrin , Semaphorins , Cell Differentiation/genetics , Leukocytes/metabolism , Osteoblasts , Osteocalcin/metabolism , Osteogenesis/genetics , Platelet-Rich Fibrin/metabolism , Semaphorins/pharmacology , Semaphorins/metabolism , Animals , Mice
9.
J Funct Biomater ; 14(8)2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37623641

ABSTRACT

The aim of this study was to test whether lyophilized conditioned media from human dental pulp mesenchymal stem cell cultures promote the healing of critical-size defects created in the calvaria of rats. Prior to the surgical procedure, the medium in which dental pulp stem cells were cultured was frozen and lyophilized. After general anesthesia, an 8 mm diameter bone defect was created in the calvaria of twenty-four rats. The defects were filled with the following materials: xenograft alone (G1) or xenograft associated with lyophilized conditioned medium (G2). After 14 or 42 days, the animals were euthanized, and the specimens processed for histologic and immunohistochemical analysis. Bone formation at the center of the defect was observed only in the G2 at 42 days. At both timepoints, increased staining for VEGF, a marker for angiogenesis, was observed in G2. Consistent with this, at 14 days, G2 also had a higher number of blood vessels detected by immunostaining with an anti-CD34 antibody. In conclusion, conditioned media from human dental pulp mesenchymal stem cell cultures had a positive effect on the regenerative process in rat critical-size bone defects. Both the formation of bone and enhancement of vascularization were stimulated by the conditioned media.

10.
Acta odontol. latinoam ; Acta odontol. latinoam;36(2): 120-127, Aug. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1513555

ABSTRACT

ABSTRACT Aim: This study evaluated cytotoxicity and antioxidant gene expression of resin cements on human gingival fibroblasts (hGF). Materials and Method: RelyX Ultimate™(RXU), Variolink™II(VLII), and RelyXU200™(RXU200) resin cements were incubated with culture medium for 24 h to obtain eluates. Then, the eluates were applied over hGF to assess cell viability at 24 h, 48 h, and 72 h and antioxidant gene expression at 24 h. hGF cultures non-exposed to the eluates were used as Control. Data were submitted to ANOVA and Bonferroni tests (α≤0.05). Results: RXU and RXU200 reduced the number of viable cells in 24 h. Longer exposure to cement extracts caused cell death. Gene expression showed peroxiredoxin 1 (PRDX1) induction by all resin cement types, and superoxide dismutase 1 (SOD1) induction by RXU200 and VLII. Moreover, RXU200 induced not only PRDX1 and SOD1, but also glutathione peroxidase 1 (GPX1), catalase (CAT), and glutathione synthetase (GSS). Conclusions: All resin cements showed toxicity, and induced antioxidant genes in hGF. Antioxidant gene induction is at least partly associated with cytotoxicity of tested cements to oxidative stress experience.


RESUMO Objetivo: O objetivo deste estudo foi avaliar a toxicidade dos cimentos resinosos Rely X Ultimate 2, Rely X U200 e Variolink II, bem como sua influência na expressão de genes antioxidantes em fibroblastos gengivais humanos. Materiais e Método: Corpos de prova de cada cimento foram colocados em meio de cultura por 24 h e os extratos correspondentes foram aplicados aos fibroblastos. A viabilidade celular foi avaliada após 24, 48 e 72 h de exposição pelo ensaio de exclusão do azul de tripano e MTT. A expressão gênica foi avaliada por PCR quantitativo após 24 h de exposição aos extratos. Estes parâmetros foram comparados aos das células não expostas aos cimentos. Os dados foram submetidos ao teste ANOVA, seguido pelo pós-teste de Bonferroni (a≤0.05). Resultados: Os resultados demonstraram que todos os cimentos promoveram redução do número de células viáveis e da atividade mitocondrial nos períodos de 48 e de 72 h (p < 0,01), sendo que o Variolink II apresentou o menor efeito e os cimentos Rely X Ultimate e Rely X U200 promoveram similarmente os maiores efeitos. A análise de expressão gênica evidenciou influência significativa em todos os cimentos avaliados sobre os níveis de transcritos de PRDX1, SOD1, GPX1 e GSS (p> 0,05), com um aumento considerável no Rely X U200. Conclusão: A indução de genes antioxidantes está, pelo menos em parte, associada à citotoxicidade dos cimentos testados para a experiência de estresse oxidativo.

11.
Sci Rep ; 13(1): 10234, 2023 06 23.
Article in English | MEDLINE | ID: mdl-37353546

ABSTRACT

An adequate wound dressing reduces time of healing, provides cost-effective care, thereby improving patients' quality life. An antimicrobial bioactivity is always desired, for that reason, the objective of this work is to design an antimicrobial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG). ChAgG nanostructured composite material is composed of chitosan from corn (Ch), and silver nanocrystals from garlic (Allium sativum). The nanocomposite obtained is the result of a series of experiments combining the graphene oxide (GrOx) with two members of the Amaryllidaceae family; garlic and onion (Allium cebae), which contain different sulfur materials. The characterization arrays confirmed the successful production of silver crystal, graphene oxidation and the blending of both components. The role of the chitosan as a binder between graphene and silver nanocrystals is proved. Moreover, the study discusses garlic as an optimal source that permits the synthesis of silver nanocrystals (AgNCs) (⁓ 2 to 10 nm) with better thermal and crystallinity properties. It was also confirmed the successful production of the ChAgG nanocomposite. Escherichia coli and Staphylococcus aureus were used to demonstrate the antibacterial bioactivity and L-929 fibroblast cells were utilized to visualize their biocompatibility. The proposed ChAgG nanomaterial will be useful for functionalizing specific fiber network that represents current challenging research in the fabrication of bioactive wound dressings.


Subject(s)
Anti-Infective Agents , Chitosan , Graphite , Metal Nanoparticles , Nanocomposites , Nanoparticles , Humans , Chitosan/chemistry , Graphite/chemistry , Silver/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Infective Agents/chemistry , Escherichia coli , Nanocomposites/chemistry , Bandages , Metal Nanoparticles/chemistry
12.
Eur J Oral Sci ; 131(4): e12937, 2023 08.
Article in English | MEDLINE | ID: mdl-37212743

ABSTRACT

This study evaluated the influence of different implant diameters, insertion torques, and transmucosal heights on the loosening of abutments installed on short implants, after mechanical cycling. The Morse taper connection implants (n = 96) tested were 5 mm high, divided according to the platform diameter: 4 or 6 mm. A universal abutment was coupled to each implant (with different transmucosal heights: 1 or 5 mm). The sets were subdivided into 20- and 32-Ncm torque. After the cycle fatigue test, the detorque values were measured with a digital torque indicator. After mechanical cycling, the mean detorque values obtained for the abutment with 20-Ncm insertion torque were lower than for implants with 32-Ncm insertion torque, regardless of the platform diameter or transmucosal height. In the 20-Ncm torque group, there was no statistically significant difference in the detorque values between platform diameters or transmucosal heights. Otherwise, for 32-Ncm sets, a smaller platform diameter (4 mm), and a longer transmucosal height (5 mm) showed the lowest detorque values. In conclusion, implants placed with 32-Ncm insertion torque and abutments with 1 mm transmucosal height and a 6 mm implant diameter demonstrated the highest detorque values.


Subject(s)
Dental Implant-Abutment Design , Dental Implants , Torque , Dental Abutments , Materials Testing , Stress, Mechanical , Bone Screws , Dental Stress Analysis
13.
Bioengineering (Basel) ; 10(5)2023 May 19.
Article in English | MEDLINE | ID: mdl-37237680

ABSTRACT

The aim of this study was to histologically verify the performance of pulp-derived stem cells used in the pulp-dentin complex regeneration. Maxillary molars of 12 immunosuppressed rats were divided into two groups: the SC (stem cells) group, and the PBS (just standard phosphate-buffered saline) group. After pulpectomy and canal preparation, the teeth received the designated materials, and the cavities were sealed. After 12 weeks, the animals were euthanized, and the specimens underwent histological processing and qualitative evaluation of intracanal connective tissue, odontoblast-like cells, intracanal mineralized tissue, and periapical inflammatory infiltrate. Immunohistochemical evaluation was performed to detect dentin matrix protein 1 (DMP1). In the PBS group, an amorphous substance and remnants of mineralized tissue were observed throughout the canal, and abundant inflammatory cells were observed in the periapical region. In the SC group, an amorphous substance and remnants of mineralized tissue were observed throughout the canal; odontoblasts-like cells immunopositive for DMP1 and mineral plug were observed in the apical region of the canal; and a mild inflammatory infiltrate, intense vascularization, and neoformation of organized connective tissue were observed in the periapical region. In conclusion, the transplantation of human pulp stem cells promoted partial pulp tissue neoformation in adult rat molars.

14.
Braz Oral Res ; 37: e43, 2023.
Article in English | MEDLINE | ID: mdl-37132730

ABSTRACT

The present study evaluated the effect of the taper angle of different internal conical connection implants and cyclic loading on the implant-abutment bacterial seal. A total of 96 implant-abutment sets were divided into eight groups. Four groups of different taper degrees with cyclic mechanical loading of 500,000 cycles per sample, with a 120-N load at 2 Hz before analysis [16DC (16-degree, cycled), 11.5DC (11.5-degree, cycled), 3DC (3- degree, cycled) and 4DC (4- degree, cycled)] were compared to four control groups without cyclic loading [16D (16-degree), 11.5D (11.5-degree), 3D (3-degree), and 4D (4-degree)]. Microbiological analysis was performed by immersing all samples in a suspension containing Escherichia coli and incubating them at 37°C. After 14 days, the presence of bacterial seals was evaluated. Fisher-Freeman-Halton exact tests and binomial tests were performed (5% significance level). The groups showed significant differences in bacterial seal, and mechanical load cycling improved the bacterial seal in the 3DC group. In all other groups, no significant differences in bacterial seal were found between cycled and uncycled samples. To conclude, the internal conical connection with a 3-degree taper angle showed better results than the other connection with different angles when subjected to load cycling. However, none of the angles tested were fully effective in sealing the implant-abutment interface.


Subject(s)
Dental Implants , Dental Implants/microbiology , Dental Abutments , Dental Implant-Abutment Design
15.
Photobiomodul Photomed Laser Surg ; 41(4): 167-174, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37074308

ABSTRACT

Objective: This study qualitatively and quantitatively evaluated the transmission of light through a collagen membrane and the consequent local bone formation in a critical bone defect in vitro and in an animal model. Background: Currently, bone substitutes and collagen membranes are used to promote new bone formation; however, when associated with photobiomodulation, biomaterials can act as a barrier, hindering the passage of light radiation to the area to be treated. Methods: Light transmittance was evaluated in vitro with a power meter and a 100 mW, 808 nm laser source with and without membrane. Twenty-four male rats received a critical surgical defect of 5 mm in diameter in the calvarial bone, subsequently a biomaterial (Bio-Oss; Geistlich®, Switzerland) was applied, and the animals were divided into the following three groups: G1-collagen membrane and no irradiation; G2-collagen membrane and photobiomodulation (irradiation with 4 J of 808 nm); and G3-photobiomodulation (4 J) followed by a collagen membrane. Histomophometric analyses were performed at 7 and 14 days after euthanasia. Results: The membrane reduced the light transmittance (808 nm) by an average of 78%. Histomophometric analyses showed significant differences in new blood vessels on day 7 and bone neoformation on day 14. Irradiation without membrane interposition resulted in a 15% more neoformed bone compared with the control (G1), and 6.5% more bone compared with irradiation over the membrane (G2). Conclusions: The collagen membrane interferes with light penetration during photobiomodulation, decreases light dosimetry on the wound area, and interferes with bone neoformation.


Subject(s)
Biocompatible Materials , Bone and Bones , Collagen , Animals , Male , Rats , Osteogenesis , Rats, Wistar
16.
Int J Pharm ; 634: 122672, 2023 Mar 05.
Article in English | MEDLINE | ID: mdl-36738810

ABSTRACT

Etidocaine (EDC) is a long-acting local anesthetic of the aminoamide family whose use was discontinued in 2008 for alleged toxicity issues. Ionic gradient liposomes (IGL) are nanostructured carriers for which an inner/outer gradient of ions increases drug upload. This work describes IGLEDC, a formulation optimized by Design of Experiments, composed of hydrogenated soy phosphatidylcholine:cholesterol:EDC, and characterized by DLS, NTA, TEM/Cryo-TEM, DSC and 1H NMR. The optimized IGL showed significant encapsulation efficiency (41 %), good shelf stability (180 days) and evidence of EDC interaction with the lipid bilayer (as seen by DSC and 1H NMR results) that confirms its membrane permeation. In vitro (release kinetics and cytotoxicity) tests showed that the encapsulation of EDC into the IGL promoted sustained release for 24 h and decreased by 50 % the intrinsic toxicity of EDC to Schwann cells. In vivo IGLEDC decreased the toxicity of EDC to Caenorhabditis elegans by 25 % and extended its anesthetic effect by one hour, after infiltrative administration, at clinically used (0.5 %) concentration, in rats. Thus, this novel drug delivery system is a promise for the possible reintroduction of EDC in clinics, aiming at the control of operative and postoperative pain.


Subject(s)
Anesthesia , Liposomes , Rats , Animals , Liposomes/chemistry , Etidocaine , Anesthetics, Local , Ions/chemistry
17.
J Stomatol Oral Maxillofac Surg ; 124(1S): 101292, 2023 02.
Article in English | MEDLINE | ID: mdl-36150689

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the effect of ozone therapy on new bone formation and inflammation modulation in defects of rat calvaria filled with autogenous bone. MATERIAL AND METHODS: Critical size defects were created in the calvaria of 24 male Wistar rats. The animals were randomly divided into four groups according to the treatment: G1: clot; G2: clot and covered with xenogenic membrane; G3: particulate autogenous bone graft; G4: autogenous bone graft and application of 3 mL O2/O3 gas mixture (10 µg/ml). The defects were filled immediately after surgery with a bilateral retroauricular application, in the region immediately above the incision. After 21 days, the animals were euthanized, and the samples were processed for morphometric evaluations designed to measure both the intensity of the inflammatory infiltrate, and the presence of new bone formation in the defect. RESULTS: The results showed a lower inflammation score and higher mean of newly formed bone in the region of the defect for the group associated with ozone therapy (G4). The bone formed in the region of the defect could be observed as being more lamellar and mineralized in the case of associated ozone therapy. CONCLUSION: Ozone therapy represents a promising adjuvant therapy to accelerate tissue regeneration.


Subject(s)
Osteogenesis , Ozone , Humans , Rats , Male , Animals , Rats, Wistar , Skull/surgery , Inflammation/therapy , Ozone/pharmacology , Ozone/therapeutic use
18.
Arch Dermatol Res ; 315(3): 559-567, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36201046

ABSTRACT

Tissue engineering focuses on wound healing and tissue regeneration. Platelet-rich fibrin (PRF) is a fibrin matrix containing cytokines, growth factors and cells that are gradually released into the wound over time. This study aimed to evaluate the effect of PRF membranes on wound repair and microbial control in infected wounds. Skin wounds were performed on the dorsum of rats using a 6 mm diameter metal punch. The defects were randomly assigned into four groups (n = 12/each) accordingly to the treatment: G1, noninfected wound filled only with clot; G2, noninfected wound with PRF; G3, infected wound (S. aureus) without PRF; G4, infected wound (S. aureus) with PRF. After 7 and 14 days, macroscopic and histological analyses of the wounds were performed. Furthermore, the quantification of ß-defensin in PRF was measured by ELISA. At 14 days, the groups with PRF (G2 and G4) had wound sizes significantly smaller than the original defects (6 mm) (p < 0.05) and significantly smaller than those not treated with PRF, in both the infected and noninfected groups (p < 0.05). Furthermore, the groups with infected wounds (G3 and G4) demonstrated a significantly lower inflammation score in the PRF group than in the noninfected groups (p < 0.05). In vitro analysis of ß-defensin was performed in all PRF membrane groups, and the median value was 1.444 pg/mL. PRF in the wounds of both control and infected rats played an important role in the modulation of tissue healing, most notably in infected sites.


Subject(s)
Platelet-Rich Fibrin , Soft Tissue Injuries , beta-Defensins , Rats , Animals , Platelet-Rich Fibrin/metabolism , Staphylococcus aureus , beta-Defensins/metabolism , beta-Defensins/pharmacology , Wound Healing , Skin
19.
J Stomatol Oral Maxillofac Surg ; 124(1S): 101372, 2023 02.
Article in English | MEDLINE | ID: mdl-36574881

ABSTRACT

OBJECTIVE: Guided bone regeneration (GBR) is a technique that involves the placement of mechanical barriers to protect the blood clot, and create an isolated space to prevent competition from epithelial and connective tissues in bone augmentation treatments. Collagen membranes stand out from other materials available for performing regenerative surgeries, and are widely used because of their ability to promote cell adhesion and homeostasis, and their biocompatibility, ease of handling, and low immunogenicity. In this context, researchers have investigated xenogenic membranes/barriers that cost less and have slower resorption rates. The current study aimed to assess the osteogenic potential induced by a crosslinked, synthesized xenogenic membrane 100 µm thick when applied in vivo to critical defects in rat calvaria. MATERIAL AND METHODS: Critical size defects were created in the calvaria of thirty male Wistar rats, and randomly divided into the following two groups: G1 - clot covered with a commercial xenogenic membrane (Lumina-Coat®, Criteria, Brazil), and G2 - clot covered with a synthesized xenogenic membrane. The animals were euthanized after 7, 15 and 30 days, and samples of calvaria were processed to perform morphometric evaluations to measure bone neoformation in the defect region. In addition, ultrastructural characterization of the collagen membranes was performed by scanning electron microscope. The quantitative analyses were carried out by adopting a significance level of 5%. RESULTS: The ultrastructural characterization revealed that the synthesized membrane had thicker collagen fibers and a more cohesive surface, compared with the Lumina-Coat® collagen membrane (G1). There was no significant difference in bone neoformation between the membranes (p>0.05), at any of the time periods analyzed. The bone quantification area increased significantly over time for both membranes (p<0.05). CONCLUSION: The synthesized membrane exhibited morphological characteristics similar to those of the commercial membrane evaluated, allowed potentially active participation in the bone neoformation process, and served as a low-cost alternative for GBR procedures.


Subject(s)
Collagen , Osteogenesis , Rats , Male , Humans , Animals , Rats, Wistar , Collagen/chemistry , Collagen/pharmacology , Bone Regeneration , Skull/surgery
20.
Edumecentro ; 152023.
Article in Spanish | LILACS | ID: biblio-1448164

ABSTRACT

Fundamento: el acto de cuidar está implícito en el proceso de trabajo de los profesionales de la enfermería y sustentado en el uso de teorías y modelos que desarrollan aspectos filosóficos y humanísticos sobre el cuidado. Objetivo: diagnosticar el nivel de preparación de los profesionales de enfermería sobre los modelos enfermeros en los servicios de Neonatología. Métodos: se realizó un estudio descriptivo de corte transversal en el Hospital Ginecobstétrico "Ana Betancourt de Mora" de la Universidad de Ciencias Médicas de Camagüey durante 2022. Se aplicaron métodos teóricos: inductivo-deductivo, analítico-sintético e histórico-lógico; y empíricos: cuestionario para la caracterización de los profesionales y el diagnóstico del nivel de preparación en cuanto a teorías y modelos enfermeros. Resultados: el diagnóstico realizado permitió conocer las carencias de los enfermeros quienes reconocieron no haber recibido talleres, cursos y/o entrenamiento afines con su competencia y desempeño, su nivel de preparación estuvo entre adecuado y medianamente adecuado, a pesar de que la mayoría tenía más de cinco años de experiencia laboral. Conclusiones: los resultados evidenciaron la insuficiente preparación de los profesionales sobre las teorías y modelos enfermeros que constituyen base teórica y científica para las intervenciones con los pacientes recién nacidos ubicados en la sala de Neonatología.


Background: the act of caring is implicit in the work process of nursing professionals and is supported by the use of theories and models that develop philosophical and humanistic aspects of care. Objective: to diagnose the level of preparation of nursing professionals on nursing models in Neonatology services. Methods: a descriptive cross-sectional study was carried out at "Ana Betancourt de Mora" Gynecological and Obstetric Hospital belonged to the University of Medical Sciences in Camagüey during 2022. Inductive-deductive, analytical-synthetic and historical-logical approaches were applied as theoretical methods; a questionnaire for the characterization of the professionals and the diagnosis of the level of preparation in terms of nursing theories and models were used as empirical ones. Results: the diagnosis made allowed us to know the deficiencies of the nurses who recognized that they had not received workshops, courses and/or training related to their competence and performance, their level of preparation was between adequate and moderately adequate, despite the fact that the majority had more than five years of work experience. Conclusions: the results showed the insufficient preparation of the professionals on the nursing theories and models which constitute a theoretical and scientific basis for interventions with newborn patients located in the Neonatology room.


Subject(s)
Education, Medical , Education, Nursing , Education, Professional , Mentoring , Learning
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