SAMIRA SALMERON
@usp.br
Professor
University of Sao Paulo / Inga University Center
EDUCATION
DDS, MSc, PhD, Bauru Dental School, University of Sao Paulo
Scopus Publications
Scopus Publications
Leandro Costa, Júlia Luiz, Vinícius Petronilho, Monike Destefani, Ana Casaroto, and Samira Salmeron
Quintessence Publishing
Purpose: To evaluate the incorporation of liquid platelet-rich fibrin in different collagen matrices in vitro. Materials and Methods: Collagen matrices with liquid platelet-rich fibrin were used and divided into the following test groups (n = 5): Mucoderm (MD), Mucograft (MG), and Fibro-Gide (FG). After incubating the collagen matrices in liquid platelet-rich fibrin, histologicl and fluid absorption capacity analysis were performed. Intergroup comparisons of cell count, blood plasma penetration area, and fluid absorption capacity were performed using one-way ANOVA and Tukey tests. Intragroup comparisons of fluid absorption capacity were made using the independent t test with a 5% significance level. Results: Descriptive qualitative analysis showed total incorporation of liquid platelet-rich fibrin in the FG group, while the MG and MD groups showed only partial and shallow incorporation, respectively. There was a statistically significant difference among the three groups regarding inflammatory cell infiltration (P = .000), with the FG group presenting the highest number of cells in the matrices (577.15 ± 54.88). The FG group showed an area of total blood plasma penetration into the matrix, followed by the MG group with partial penetration, and the MD group with minor penetration area (P = .000). Considering the fluid absorption capacity analysis, only groups FG and MG were statistically different when comparing the liquid platelet-rich fibrin absorption coefficient (P = .017), with higher absorption in group FG (14.30 ± 3.35). Conclusions: The FG collagen matrix showed a good capacity for liquid platelet-rich fibrin incorporation in vitro.
Renato Bitencourt Rosado, Eder José Cruz, Thainá Pinheiro de Souza, Karina Maria Salvatore Freitas, Mariana Aparecida Lopes Ortiz, and Samira Salmeron
Informa UK Limited
Rosangela Colet, Paula Cotrin, Renata Cristina Oliveira, Fabricio Pinelli Valarelli, Ricardo Cesar Gobbi de Oliveira, Samira Salmeron, and Karina Maria Salvatore Freitas
Elsevier BV
Ricardo Kehrwald, Hebert Sampaio de Castro, Samira Salmeron, Ricardo Alves Matheus, Gustavo Machado Santaella, and Polyane Mazucatto Queiroz
Georg Thieme Verlag KG
Abstract Objective This study was developed to evaluate the influence of voxel size on bone measurements for implant planning. Materials and Methods The research was performed by using edentulous synthetic human mandibles with different levels of bone resorption. For each mandible, height and bone thickness were measured with a digital caliper. The PaX-i3d device was used to acquire the volumes of the five mandibles, with 50kVp, 4 mA, and a voxel size of 0.08 mm. After the acquisition, the images were reconstructed in the software CS three-dimensional Imaging, with four different sizes of voxels: 0.1, 0.2, 0.3, and 0.4 mm. All volumes were analyzed by a single evaluator who performed measurements to obtain bone height and thickness, using the reference points that were considered in obtaining the gold standard. The data were analyzed by ANOVA with a significance level of 5%. Results There was no significant difference in the measurements obtained with different voxel sizes, both for bone height measurements and bone thickness. There was no statistically significant difference in measurements in thickness in comparison to the gold standard. Conclusion When necessary, to measure height and bone thickness, it is possible to recommend voxel images of larger size (0.40 mm) without compromising the quality of the patient's clinical planning.
Dayane Maria Braz Nogueira, André Luiz de Faria Figadoli, Patrícia Lopes Alcantara, Karina Torres Pomini, Iris Jasmin Santos German, Carlos Henrique Bertoni Reis, Geraldo Marco Rosa Júnior, Marcelie Priscila de Oliveira Rosso, Paulo Sérgio da Silva Santos, Mariana Schutzer Ragghianti Zangrando,et al.
MDPI AG
In this experimental protocol, the objective was to evaluate the biological behavior of two xenogenic scaffolds in alcohol-induced rats through histomorphometric and Picrosirius Red staining analysis of non-critical defects in the tibia of rats submitted or not to alcohol ingestion at 25% v/v. Eighty male rats were randomly divided into four groups (n = 20 each): CG/B (water diet + Bio-Oss® graft, Geistlich Pharma AG, Wolhusen, Switzerland), CG/O (water diet + OrthoGen® graft, Baumer, Mogi Mirim, Brazil), AG/B (25% v/v alcohol diet + Bio-Oss® graft), and AG/O (25% v/v alcohol diet + OrthoGen® graft). After 90 days of liquid diet, the rats were surgically obtained, with a defect in the tibia proximal epiphysis; filled in according to their respective groups; and euthanized at 10, 20, 40 and 60 days. In two initial periods (10 and 20 days), all groups presented biomaterial particles surrounded by disorganized collagen fibrils. Alcoholic animals (AG/B and AG/O) presented, in the cortical and medullary regions, a reactive tissue with inflammatory infiltrate. In 60 days, in the superficial area of the surgical cavities, particles of biomaterials were observed in all groups, with new compact bone tissue around them, without complete closure of the lesion, except in non-alcoholic animals treated with Bio-Oss® xenograft (CG/B), where the new cortical interconnected the edges of the defect. Birefringence transition was observed in the histochemical analysis of collagen fibers by Picrosirius Red, in which all groups in periods of 10 and 20 days showed red-orange birefringence, and from 40 days onwards greenish-yellow birefringence, which demonstrates the characteristic transition from the formation of thin and disorganized collagen fibers initially to more organized and thicker later. In histomorphometric analysis, at 60 days, CG/B had the highest volume density of new bone (32.9 ± 1.15) and AG/O the lowest volume density of new bone (15.32 ± 1.71). It can be concluded that the bone neoformation occurred in the defects that received the two biomaterials, in all periods, but the Bio-Oss® was superior in the results, with its groups CG/B and AG/B displaying greater bone formation (32.9 ± 1.15 and 22.74 ± 1.15, respectively) compared to the OrthoGen® CG/O and AG/O groups (20.66 ± 2.12 and 15.32 ± 1.71, respectively), and that the alcoholic diet interfered negatively in the repair process and in the percentage of new bone formed.
Marcelo H. Tonin, Fabiano C. Brites, José R. Mariano, Karina M. S. Freitas, Mariana A. L. Ortiz, and Samira Salmeron
Georg Thieme Verlag KG
Abstract Objective Currently, dental implants are a predictable treatment option for oral rehabilitation; however, complications such as peri-implant diseases are increasing every day. Thus, the aim of this study was to verify the efficacy, in vitro, of two protocols against cultures of periodontal biofilm and Staphylococcus aureus. Material and Methods Petri dishes for each of the following groups were used: control groups (C)—plates inoculated with periodontal biofilm (C.B; n = 4) or S. aureus (C.SA; n = 4) without any treatment; laser groups—plates inoculated with periodontal biofilm (low-level laser therapy [LLLT].B; n = 4) or S. aureus (LLLT.SA; n = 4) and treated with LLLT (660 nm, 30 mW, 50 J/cm2, and 47 seconds); antimicrobial photodynamic therapy groups (aPDT)—plates inoculated with periodontal biofilm (aPDT.B; n = 4) or S. aureus (aPDT.SA; n = 4) and treated with aPDT (red laser 660 nm, 30 mW, 50 J/cm2, 47 seconds + toluidine blue O (TBO) 100 µg/mL, and 1 minute). After treatments were performed, the contents of all plates were diluted and seeded for counting colony-forming units (CFUs). Statistical Analysis Results were analyzed with one-way analysis of variance (ANOVA), Tukey’s test, comparison of percentages, and independent t-tests with a 5% significance level. Results Both treatments, LLLT and aPDT, significantly reduced the number of CFUs for the two types of culture, LLLT.B (3.69 × 106 ± 0.20), aPDT.B (2.79 × 106 ± 0.13), LLLT.SA (4.10 × 106 ± 0.12), and aPDT.SA (3.23 × 106 ± 0.10) when compared with control groups C.B (5.18 × 106 ± 0.43) and C.SA (5.81 × 106 ± 0.16; p = 0.000). When treatment groups were compared separately, there was also a statistically significant difference (p = 0.000). None of the protocols were able to eliminate cultured microorganisms. Conclusion The LLLT and aPDT protocols effectively reduced cultures of periodontal biofilm and S. aureus in vitro, with the superiority of aPDT.
Melissa Faccini, Felipe Agostini, Tassio Drieu, Francisco Ubiratan Ferreira de Campos, Aguinaldo Garcez, Glauber Fabre Carinhena, Samira Salmeron, Ana Regina Casaroto, Fabricio Pinelli Valarelli, and Karina Maria Salvatore Freitas
Georg Thieme Verlag KG
Abstract Objectives The aim of the study is to histologically evaluate the effect of ozone therapy on orthodontic force induction in an animal model. Materials and Methods Twenty-four Wistar rats were divided into three groups (n = 8). A NiTi coil spring was installed from the maxillary first molar to the maxillary central incisor. G1 was control and G2/G3 received 1 mL of ozonated gas at concentrations of 10 and 60 µg/mL, in the buccal mucosa above the first molar roots. The animals were euthanized 3 and 5 days after the procedure. Histological sections were obtained, longitudinally of the first molar’ long axis, in the mesiodistal direction. The number of osteoclasts, osteoblasts, blood vessels, polymorphonuclear and mononuclear cells, formation of osteoid tissue and hyaline areas, and root resorption were evaluated with light microscope, in tension and pressure sides. Intergroup comparisons were performed with Kruskal–Wallis, Dunn, and Chi-square tests. Results At 3-days pressure side, a greater number of osteoclasts was observed in ozone groups and greater number of blood vessels and polymorphonuclear cells were observed in G2. On the tension side, there was a significantly greater number of blood vessels, osteoblasts, and mononuclear cells in G2. At 5-days pressure side, there was a significantly greater number of osteoclasts in G2, blood vessels and osteoblasts in the ozone groups, and lesser number of polymorphonuclear cells in G3. Conclusion Ozone therapy increased the number of osteoclasts on the pressure side and osteoblasts on tension side, in 10 µg/mL concentration, demonstrating histological parameters favorable to bone remodeling. The 60 µg/mL ozone concentration accelerated the periodontal ligament reorganization process.
Fábio Jorge Saab, Daniel Salvatore de Freitas, Paula Cotrin, Renata Cristina Oliveira, Fabricio Pinelli Valarelli, Ricardo Cesar Gobbi de Oliveira, Samira Salmeron, Célia Regina Maio Pinzan Vercelino, and Karina Maria Salvatore Freitas
Georg Thieme Verlag KG
Abstract Objective This study aimed to compare gingival recession in mandibular anterior teeth in patients with Class III malocclusion, immediately after compensatory or surgical orthodontic treatment. Materials and Methods The sample consisted of 40 patients with Class III malocclusion, divided into two groups: Group 1 (compensatory), 20 patients treated with compensatory orthodontics, with a mean initial age of 20.26 years (standard deviation [SD] . = 7.44), mean final age of 23.07 years (SD = 7.32), and mean treatment time of 2.81 years (SD =0.84). Group 2 (surgical), who undergone orthodontic–surgical treatment, with a mean initial age of 23.08 years (SD =5.48), mean final age of 25.43 years (SD =5.12), and mean treatment time of 2.35 years (SD =1.56). Intraoral photographs taken before and after removal of the fixed orthodontic appliance were used to measure the gingival recession, from the cervical of the mandibular incisors from the most cervical point of the gingival margin to the cementoenamel junction. In the initial and final cephalograms, the position of the mandibular incisors was measured. The intergroup comparison was performed using the independent t-test. Results The results showed that there was no statistically significant difference in the gingival recession at the beginning, at the end, and of changes with treatment between the compensatory and surgical groups. Conclusion It was concluded that the compensatory and surgical orthodontic treatments for Class III malocclusion showed similar results regarding the gingival recession of the mandibular incisors.
Manoel Heitor Brito, Cinthya Quagliato Nogueira, Paula Cotrin, Tiago Fialho, Renata Cristina Oliveira, Ricardo Gobbi Oliveira, Samira Salmeron, Fabrício Pinelli Valarelli, Karina Maria Salvatore Freitas, and Rodrigo Hermont Cançado
Hindawi Limited
Purpose. There is no consensus about the mechanism and efficacy in alleviating pain of the lower-level laser therapy (LLLT) during orthodontic treatment. This study aimed to evaluate the LLLT effectiveness clinically in reducing pain caused by orthodontic movement that occurs in the early stages of treatment. Methods. The sample consisted of 54 patients in need of orthodontic treatment divided into two groups. A 28 experimental patients group (initial mean age: 26.84 years old) was undergone gallium-aluminum-arsenide infrared laser application on 12 points for each tooth immediately after the installation of the first alignment archwire, and a 26 patients control group (initial mean age: 29.13 years old) was undergone to no pain control intervention at all. Pain intensity was measured by using a visual analog scale, which was marked pain level (mm) reported in 06, 24, 48, and 72 hours. The perception of pain (beginning, peak, decline, and absence) was evaluated by filling up a questionnaire. To compare the intensity and perception of pain between groups, a nonparametric Mann–Whitney has been performed. Results. The experimental group showed levels (mm) at 6 ( p < 0.001 ), 24 ( p = 0.004 ), and 48 hours ( p = 0.007 ) and perception of pain (hours) in the peak ( p = 0.026 ), decline ( p = 0.025 ), and absence ( p = 0.008 ) significantly lower compared to the group control. Conclusion. Low-level laser therapy is effective in reducing pain severity caused by orthodontic forces activation, and it promotes the analgesic action lasting effect during the most painful feeling time.
Edemar Junior, Marcos Zubek, Polyane Queiroz, Karina Freitas, Mariana Ortiz, and Samira Salmeron
Quintessence Publishing
PURPOSE
The increasing use of dental implants in oral rehabilitation has contributed to the increase of cases of peri-implantitis, a complex clinical condition that persists without an ideal treatment protocol. Therefore, this study aimed to verify the decontaminating action of the sodium bicarbonate jet in vitro, using different protocols, and the presence of visible changes on the surface of dental implants.
MATERIALS AND METHODS
Sixteen titanium implants (BioHE, Bioconnect) were used, divided into four groups (four implants per group): sterile implants (S)-negative control; implants contaminated with oral biofilm (C)-positive control; and implants contaminated with oral biofilm and decontaminated with a sodium bicarbonate jet for 30 seconds (J30) or 60 seconds (J60). The implants of groups C, J30, and J60 were contaminated in vitro with oral biofilm, then groups J30 and J60 received the respective decontamination treatments. Microbiologic analysis was performed by counting the colony-forming units (CFUs), and a qualitative descriptive analysis of the implant surface was performed after microbiologic analysis using scanning electron microscopy (SEM). Statistical analysis included one-way analysis of variance (ANOVA) and Tukey tests and the independent t test, with a .05 significance level.
RESULTS
There was a significant reduction (P < .01) in the number of CFUs in groups J30 (3.63 × 106 ± 0.32) and J60 (2.74 × 106 ± 0.21) compared with group C (5.05 × 106 ± 0.43). Both decontaminated groups were statistically different from group S, which did not show bacterial growth (P < .01). When groups J30 and J60 were compared, there was also a significant difference between them (P < .01), and the group J60 showed greater decontaminating potential. The descriptive qualitative analysis did not show any visible changes on the surface of the implants.
CONCLUSION
The sodium bicarbonate jet was effective in decontaminating titanium implants in vitro, causing no visible damage to the implant surface.
Vanessa Coelho Batalha, Raquel Abreu Bueno, Edemar Fronchetti Junior, José Ricardo Mariano, Gabriela Cristina Santin, Karina Maria Salvatore Freitas, Mariana Aparecida Lopes Ortiz, and Samira Salmeron
Georg Thieme Verlag KG
Abstract Objective The number of patients rehabilitated with dental implants has contributed to increased incidence of peri-implant diseases. Due to complex and difficult treatment, peri-implantitis is a challenge and an efficient clinical protocol is not yet established. Aim of this study was to evaluate the efficacy of two protocols for in vitro decontamination of dental implants surface. Material and Methods Twenty titanium implants (BioHE-Bioconect) were used. Implants were divided into five groups (n = 4). NC group (negative control): sterile implants; PC group (positive control): biofilm contaminated implants; S group: biofilm contaminated implants, brushed with sterile saline; SB group: biofilm contaminated implants, brushed with sterile saline and treated with air-powder abrasive system with sodium bicarbonate (1 minute); and antimicrobial photodynamic therapy (aPDT) group: biofilm contaminated implants, brushed with sterile saline and treated with antimicrobial photodynamic therapy (red laser + toluidine blue O). The implants were contaminated in vitro with subgingival biofilm and distributed in groups PC, S, SB, and aPDT. Each group received the respective decontamination treatment, except groups NC and PC. Then, all implants were placed in tubes containing culture medium for later sowing and counting of colony-forming units (CFUs). Statistical Analysis One-way analysis of variance and Tukey tests were performed, at 5% significance level. Results Significantly fewer CFUs were observed in the aPDT group (19.38 × 105) when compared with groups SB (26.88 × 105), S (47.75 × 105), and PC (59.88 × 105) (p < 0.01). Both the aPDT and SB groups were statistically different from the NC group (p < 0.01). Conclusion Proposed protocols, using air-powder abrasive system with sodium bicarbonate and aPDT, showed to be efficacious in the decontamination of dental implants surface in vitro.
Jefrey E. Rojas‐Paulús, Gustavo G. P. Manfredi, Samira Salmeron, Alberto Consolaro, Adriana C. P. Sant'Ana, Mariana S. R. Zangrando, Carla A. Damante, Sebastião L. A. Greghi, and Maria L. R. Rezende
Wiley
BACKGROUND
Bone demineralization has shown to be advantageous in autogenous onlay bone grafts and in pre-osteoblasts cultures, but such procedure has never been evaluated in particulate bone grafts. This study aimed to investigate the role of two demineralizing agents in the repair of the 8-mm critical-size defects in rats' calvaria.
METHODS
Eighty adult male Wistar rats were randomly assigned to one of eight groups as follows: particulate autogenous bone demineralized with citric acid for 15s (CA15), 30s (CA30), or 60s (CA60); particulate autogenous bone demineralized with tetracycline hydrochloride for 15s (TCN15), 30s (TCN30), or 60s (TCN60); blood clot (NC), and non-demineralized autogenous bone (PC). The calvariae were harvested at 30 and 60 postoperative days (n = 5) for blinded histological and histometric analysis of the percentage area of newly formed bone within the defects.
RESULTS
In the NC and TCN groups, bone formation was limited to the margins of the defects at 30 postoperative days, while complete closure was present in all the specimens from CA15 group. Both at 30 and 60 postoperative days, histomorphometry showed significant higher area of newly formed bone in specimens demineralized with CA than in those demineralized with TCN or non-demineralized (P < 0.05). TCN appeared to impair bone neoformation, as its use produced similar or inferior results compared to blood clot.
CONCLUSIONS
Demineralization of particulate bone grafts with CA during 15s enhanced the regeneration of critical-size defects and may be a promising adjuvant in regenerative procedures. TCN seems to be improper for this purpose. This article is protected by copyright. All rights reserved.
Felipe Agostini, Melissa Faccini, Francisco Fitarelli, Mariana Aparecida Lopes Ortiz, Samira Salmeron, Ricardo Cesar Gobbi Oliveira, Fabricio Pinelli Valarelli, Renata Cristina Oliveira, and Karina Maria Salvatore Freitas
Informa UK Limited
ABSTRACT This study aimed to compare the antibacterial effect of ozonated water and ozonated gas at different concentrations and exposure times. Staphylococcus aureus and Enterococcus faecalis were exposed to ozonated water or ozonated gas at concentrations of 20, 40 and 60 μg/mL for 1 and 2 minutes. A positive control with bacteria and a chlorhexidine 2% negative control were used. The number of colony-forming units (CFU/mL) was evaluated. The concentrations of 40 and 60 μg/mL were significantly more effective. For the E. faecalis, ozonated gas was significantly more effective than ozonated water. When compared to controls, all ozone concentrations were effective in reducing bacteria.
Melissa Faccini, Fernanda Ferruzzi, Aline Akemi Mori, Gabriela Cristina Santin, Renata Cristina Oliveira, Ricardo Cesar Gobbi de Oliveira, Polyane Mazucatto Queiroz, Samira Salmeron, Nubia Inocencya Pavesi Pini, Daniel Sundfeld,et al.
Georg Thieme Verlag KG
Abstract Objective This survey aimed to assess the effects of coronavirus disease 2019 (COVID-19) on elective and urgency/emergency dental care and dentists concerned. Materials and Methods A web-based survey was performed using Google forms questionnaire sent to dentists in Brazil. Questions included: personal information, type of dental care provided during quarantine, if emergencies increased, the dental office biosafety routine, among others. The levels of concern about the impact of quarantine on dental care and patient oral health conditions and the economic impact on dental practices were evaluated using a 0- to 10-point scale. Statistical analysis included descriptive, percentages, one-way ANOVA, Tukey, and chi-square tests. Results During quarantine, 64.6% of the dentists attended only urgency/emergency treatments, while 26.1% maintained routine appointments, and 9.3% closed the dental offices. A higher percentage of dentists from the least affected states continued routine dental treatment; dentists were younger and presented a significantly lower level of concern about dental treatments and oral health conditions of their patients. An increase in urgency/emergency procedures was reported by 44.1% of the dentists, mostly due to the unavailability of routine/elective dental care and increased patient anxiety and stress. The main causes of urgency/emergency appointments were toothache, dental trauma, and broken restorations, besides the breakage of orthodontic appliances and temporomandibular disorders. Dentists reported a high level of concern about the economic impact caused by quarantine. Conclusions The pandemic/quarantine has negatively affected the clinical routine. Personal protection/hygiene care must be adopted and reinforced by dental professionals/staff to make dental procedures safer.
Victor Hugo Souza, Jeane Eliete Laguila Visentainer, Joana Maira Valentini Zacarias, Josiane Bazzo Alencar, Patrícia Yumeko Tsuneto, Cléverson Oliveira Silva, Samira Salmeron, Cristiane Maria Colli, and Ana Maria Sell
Public Library of Science (PLoS)
Periodontitis (PD) is a chronic inflammatory process resulting from the relationship of the immune response with the components in dental plaque. Cytokines and their genetic polymorphisms seem to be involved in the immunopathogenesis of this disease. This study aimed to evaluate the correlation of IL16 polymorphism with PD. A case-control study was conducted in a sample of individuals from southern Brazil. The genotyping of IL16, rs11556218 T>G, rs4072111 C>T e rs4778889 T>C, was performed using the PCR-RFLP methodology. The serum level of IL-16 was determined using an IL-16 ELISA kit for humans. SNPStats and OpenEpi software and Wilcoxon's U test were used to perform statistical analysis. IL16 rs11556218 polymorphism was significantly associated to PD in nonsmoking patients: individuals with G/G genotype were less likely to develop PD compared to the T/T genotype (OR = 0.10; Pc = 0.019, codominant model). In addition, the TTT haplotype was associated with a high risk for PD (OR = 2.45; P = 0.01). A low IL-16 serum level was observed among individuals with PD when compared to controls (P = 0.027). Thus, the IL16 rs16556218 polymorphism and the serum levels of IL-16 were associated with periodontitis in a Brazilian sample, and this was influenced by environmental factors such as smoking.
Ana Regina Casaroto, Rafaela Alves da Silva, Samira Salmeron, Maria Lúcia Rubo de Rezende, Thiago José Dionísio, Carlos Ferreira dos Santos, Karen Henriette Pinke, Maria Fátima Guarizo Klingbeil, Priscila Aranda Salomão, Marcelo Milanda Ribeiro Lopes,et al.
MDPI AG
The presence of Candida albicans in the biofilm underlying the dental prosthesis is related to denture stomatitis (DS), an inflammatory reaction of the oral mucosa. The oral epithelium, a component of the innate immune response, has the ability to react to fungal invasion. In this study, we evaluated the in vitro effect of viable C. albicans on the apoptosis, nitric oxide (NO) production, and β-defensin 2 (hBD-2) expression and production of human palate epithelial cells (HPECs). We further determined whether or not these effects were correlated with fungal invasion of epithelial cells. Interaction between HPEC primary culture and C. albicans was obtained through either direct or indirect cell–cell contact with a supernatant from a hyphal fungus. We found that the hyphae supernatants were sufficient to induce slight HPEC apoptosis, which occurred prior to the activation of the specific mechanisms of epithelial defense. The epithelial defense responses were found to occur via NO and antimicrobial peptide hBD-2 production only during direct contact between C. albicans and HPECs and coincided with the fungus’s intraepithelial invasion. However, although the hBD-2 levels remained constant in the HPEC supernatants over time, the NO release and hBD-2 gene expression were reduced at a later time (10 h), indicating that the epithelial defense capacity against the fungal invasion was not maintained in later phases. This aspect of the immune response was associated with increased epithelial invasion and apoptosis maintenance.
Gustavo Gonçalves do Prado Manfredi, Cíntia Kazuko Tokuhara, Samira Salmeron, Érika Beatriz Spada Carvalho, Paulo Noronha Liboa‐Filho, Carla Andreotti Damante, Adriana Campos Passanezi Sant'Ana, Mariana Schutzer Ragghianti Zangrando, Sebastião Luis Aguiar Greghi, and Maria Lúcia Rubo Rezende
Wiley
Previous studies have shown substances capable of similar effects of demineralization, accelerating the process of bone remodeling. This study investigated preosteoblasts behavior in cell culture after bone demineralization with citric acid and tetracycline. Seventy‐four Wistar rats provided 144 calvarial bone samples, 126 of which were randomly divided in seven groups according to the treatment given to the surface: no demineralization (C), citric acid (CA), tetracycline (TCN) during 15, 30, and 60 s. Each group received preosteoblasts cultured for 24, 48, and 72 hr. Eighteen remaining samples were analyzed for the atomic percentage (A%) by energy dispersive spectroscopy (EDS) before and after demineralization. The average percentage of bone area covered by cells increased with time and it was significantly higher after 24 and 48 hr of culture in groups CA15s, CA30s, CA60s, TCN15s, and TCN30s than in groups TCN60 and C (p < 0.05). The cell morphology in all CA and TCN groups was shown to be compatible with more advanced stages of differentiation than in C group. The A% changed after demineralization. We conclude that demineralization with citric acid or tetracycline for 15–30 s increased the area of bone surface covered by preosteoblasts. The A% changes were not sufficient to impair the cells spreading and morphology. Bone demineralization may promote potential benefits in bone regenerative procedures.
Carla Andreotti Damante, Paula Ducati, Rafael Ferreira, Samira Salmeron, Mariana Schutzer Ragghianti Zangrando, Maria Lúcia Rubo de Rezende, Adriana Campos Passanezi Sant’Ana, Sebastião Luiz Aguiar Greghi, and Ana Carolina Magalhães
Elsevier BV
BACKGROUND
Antimicrobial photodynamic therapy (aPDT) in Dentistry has important effects as bacterial destruction in areas with periodontal disease. Some dyes applied in aPDT could present low pH and, consequently, result in tooth demineralization. This study evaluated demineralization produced by aPDT with toluidine blue O (TBO) at low pH and analyzed adhesion/proliferation of human gingival fibroblasts (HGF).
METHODS
In the 1st phase, bovine enamel and root dentin fragments received 2 treatments: PDT4 group (TBO-100 μg/ml-pH 4-60s) plus laser (660 nm, 45 J/cm(2), 1.08 J, 30 mW, 30 s, spot 0.024 cm(2), 1.25 W/cm(2), sweeping, non-contact) and CA group (citric acid plus tetracycline-pH 1-180 s). Surface hardness loss and tooth wear were statistically analyzed (Student's t test, ANOVA/Tukey, p<0.05). In the 2nd phase, human dentin fragments were divided in C (control group-scaling and root planing), PDT4 and CA. HGF (10(4), 5th passage) were cultured on these fragments for 24, 48 and 72 h and counted in scanning electron microscopy photographs. Number of HGF was analyzed using repeated-measures ANOVA and Tukey (p<0.05).
RESULTS
Percentage of surface hardness loss was similar in dentin for PDT4 (71.5%) and CA (76.1%) (p>0.05) and higher in enamel for CA (68.0%) compared to PDT4 (34.1%) (p<0.05). In respect to wear, no difference was found between PDT4 (dentin: 12.58 μm, enamel: 12.19 μm respectively) and CA (dentin: 11.74 μm and enamel: 11.03 μm) (p>0.05). Number of HGF was higher after 72 h in CA group (2.66, p<0.05) compared to PDT4 (2.2) and C (1.33).
CONCLUSION
PDT4 is not as aggressive as CA for enamel. However, dentin demineralized promoted by PDT4 does not stimulate HGF adhesion and proliferation as CA.
Maria Lúcia R de Rezende, Pedro T.G. Coesta, Rodrigo C. de Oliveira, Samira Salmeron, Adriana C.P. Sant’Ana, Carla A. Damante, Sebastião L.A. Greghi, and Alberto Consolaro
Wiley
BACKGROUND
Previous studies have demonstrated that bone demineralization can improve consolidation in bone grafts. The biologic mechanisms underlying this phenomenon remain unclear.
METHODS
Twelve adult male guinea pigs were used in this experiment. Forty-five bone samples removed from the calvaria of nine animals were divided in groups (n = 9) according to the time of demineralization with citric acid (50%, pH 1): 15, 30, 90, and 180 seconds and non-demineralized samples (control). Preosteoblasts (MC3T3-E1) were cultured on the bone samples for 24, 48, and 72 hours (n = 3). Fifteen samples removed from the remaining three animals were analyzed by scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) after demineralization (n = 3).
RESULTS
The number of preosteoblasts increased significantly with time in all groups. The bone surface area covered by these cells increased with time, except in the control group. Intragroup differences occurred between 24 and 72 hours (P < 0.05). Samples demineralized for 30 seconds showed greater area covered by preosteoblast cells than for the other times of demineralization in all periods of cell culture (P < 0.05) without a statistically significant difference compared with 15 seconds. SEM/EDS showed diminished content of calcium (Ca) after 15 seconds of demineralization, but the Ca content increased after 180 seconds of demineralization (P < 0.05). The phosphorus (P) amount increased significantly only after 30 seconds of demineralization (P < 0.5). The sulfur (S) content was increased in demineralized samples in relation to non-demineralized ones, reaching the highest level after 90 seconds, when the difference became significant in relation to all the other times of demineralization (P < 0.05). Magnesium (Mg) content did not differ significantly between demineralized and non-demineralized samples.
CONCLUSIONS
Bone surfaces demineralized for 30 seconds increased the spreading of preosteoblasts as well as the surface area covered by these cells. Bone demineralization deserves to be studied in periodontal and maxillofacial regenerative procedures.
Samira Salmeron, Maria L.R. Rezende, Alberto Consolaro, Adriana C.P. Sant’Ana, Carla A. Damante, Sebastião L.A. Greghi, and Euloir Passanezi
Wiley
BACKGROUND
To the best of the authors' knowledge, a standard protocol for treating peri-implantitis is not yet established.
METHODS
A total of 150 titanium disks with smooth or rough surfaces contaminated with microbial biofilm were implanted subcutaneously in rats after undergoing one of three treatments: 1) low-intensity laser (LIL); 2) antimicrobial photodynamic therapy (aPDT); or 3) toluidine blue O (TBO). Sterile and contaminated disks served as negative (NC) and positive (C) control groups, respectively. After days 7, 28, and 84, tissue inflammation was evaluated microscopically by measuring the density of collagen fibers (degree of fibrosis) and concentration of polymorphonuclear neutrophils.
RESULTS
Surface texture did not affect the degree of inflammation, but the area of reactive tissue was significantly greater for rough implants (2.6 ± 3.7 × 10(6) µm(2)) than for smooth ones (1.9 ± 2.6 × 10(6) µm(2); P = 0.0377). Group C presented the lowest and group NC presented the highest degree of fibrosis with significance only after day 7; these groups had the highest and lowest scores, respectively, for degree of inflammation. Group C showed the largest area of reactive tissue (9.11 ± 2.10 × 10(6) µm(2)), but it was not significantly larger than group LIL (P = 0.3031) and group TBO (P = 0.1333). Group aPDT showed the smallest area (4.34 ± 1.49 × 10(6) µm(2)) of reactive tissue among the treatment groups. After day 28, groups LIL, aPDT, TBO, and C resembled group NC in all the studied parameters.
CONCLUSION
Group aPDT showed more favorable results in parameter area of reactive tissue than the other methods after day 7, but over longer time periods all methods produced outcomes equivalent to sterile implants.