Publications by authors named "Maristela Barbosa Portela"

43 Publications

Fabrication and characterization of remineralizing dental composites containing calcium type pre-reacted glass-ionomer (PRG-Ca) fillers.

Dent Mater 2021 May 4. Epub 2021 May 4.

Analitical Laboratory of Restorative Biomaterials - LABiom-R, School of Dentistry, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil. Electronic address:

Objective: To fabricate and characterize dental composites with calcium type pre-reacted glass-ionomer (PRG-Ca) fillers.

Methods: PRG-Ca fillers were prepared by the reaction of calcium fluoroaluminosilicate glass with polyacrylic acid. Seven dental composites were produced from the same organic matrix (70/30wt% Bis-GMA/TEGDMA), with partial replacement of barium borosilicate (BaBSi) fillers (60wt%) by PRG-Ca fillers (wt%): E0 (0) - control, E1 (10), E2 (20), E3 (30), E4 (40), E5 (50) and E6 (60). Enamel remineralization was evaluated in caries-like enamel lesions induced by S. mutans biofilm using micro-CT. The following properties were characterized: degree of conversion (DC%), roughness (Ra), Knoop hardness (KHN), flexural strength (FS), flexural modulus (FM), water sorption (W), water solubility (W), and translucency (TP). Data were analyzed to one-way ANOVA and Tukey's HSD test (α=0.05).

Results: All composites with PRG-Ca induced enamel remineralization. E0 and E1 presented similar and highest DC% than E2=E3=E4=E5=E6. Ra and KHN were not influenced by PRG-Ca fillers (p<0.05). The higher the content of PRG-Ca, the lower FS, FM and TP (p<0.05). W increased linearly with the content of PRG-Ca fillers (p<0.05). E6 presented the highest W (p<0.05), while the W of the other composites were not different from each other (p>0.05).

Significance: Incorporation of 10-40wt.% of PRG-Ca fillers endowed remineralizing potential to dental composites without jeopardizing the overall behavior of their physicochemical properties. Dental composites with PRG-Ca fillers seems to be a good alternative for reinforcing the enamel against caries development.
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http://dx.doi.org/10.1016/j.dental.2021.04.004DOI Listing
May 2021

Physicochemical properties and biological effects of quaternary ammonium methacrylates in an experimental adhesive resin for bonding orthodontic brackets.

J Appl Oral Sci 2021 3;29:e20201031. Epub 2021 May 3.

Universidade Federal do Rio Grande, Pós-Graduação em Odontologia da do Sul, Porto Alegre, RS, Brasil.

Methodology: Fixed orthodontic appliances may lead to biofilm accumulation around them that may increase caries risk. This study aimed to evaluate the influence of quaternary ammonium methacrylates (QAMs) on the physicochemical properties, cytotoxicity, and antibacterial activity of adhesive resins for orthodontic purposes. A base resin was prepared with a comonomer blend and photoinitiator/co-initiator system. Two different QAMs were added to the base adhesive: dimethylaminododecyl methacrylate at 5 wt.% (DMADDM) or dimethylaminohexadecyl methacrylate (DMAHDM) at 10 wt.%. The base adhesive, without QAMs, (GC) and the commercial Transbond™ XT Primer 3M (GT) were used as control. The resins were tested immediately and after six months of aging in the water regarding the antibacterial activity and shear bond strength (SBS). The antibacterial activity was tested against Streptococcus mutans via metabolic activity assay (MTT test). The groups were also tested for the degree of conversion (DC) and cytotoxicity against keratinocytes.

Results: The resins containing QAM showed antibacterial activity compared to the commercial material by immediately reducing the metabolic activity by about 60%. However, the antibacterial activity decreased after aging (p<0.05). None of the groups presented any differences for SBS (p>0.05) and DC (p>0.05). The incorporation of DMADDM and DMAHDM significantly reduced the keratinocyte viability compared to the GT and GC groups (p<0.05).

Conclusion: Both adhesives with QAMs showed a significant reduction in bacterial metabolic activity, but this effect decreased after water aging. Lower cell viability was observed for the group with the longer alkyl chain-QAM, without significant differences for the bonding ability and degree of conversion. The addition of QAMs in adhesives may affect the keratinocytes viability, and the aging effects maybe decrease the bacterial activity of QAM-doped materials.
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http://dx.doi.org/10.1590/1678-7757-2020-1031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8092807PMC
May 2021

Effects of a biomimetic analog-based experimental bonding system on caries-affected and sound dentin.

Microsc Res Tech 2020 Dec 13;83(12):1610-1622. Epub 2020 Sep 13.

Analytical Laboratory of Restorative Biomaterials, School of Dentistry, Universidade Federal Fluminense, Niterói, Brazil.

This study compared the ultrastructure, chemical composition, and proteases activity (PA) of sound (SD) and caries-affected dentin (CAD) in the dentin hybrid layer after using an experimental bonding system containing pyromellitic dianhydride glycerol methacrylate and biomimetic analogs. The bonding system used a three step and a total-etch procedure. Polyacrylic acid (5%) and sodium trimetaphosphate (5%) were added to the primer and monocalcium phosphate monohydrate (9%), beta-tricalcium phosphate (10.5%), and calcium hydroxide (0.5%) were added to the adhesive. Transmission electron microscopy (TEM) was used to evaluate the resultant structure, particularly the adhesive-dentin and the demineralized-SD interfaces. The chemical composition was evaluated through energy-dispersive X-ray spectroscopy (EDS) and selected area electron diffraction (SAED). The PA was measured with the Coomassie Blue-G250 coloring test, and the PA data were analyzed by ANOVA. EDS identified the presence of isolated calcium phosphate nanoparticles in the demineralized region; however, the SAED analysis did not show any evidences of hydroxyapatite (HA) neoformation in SD and CAD. The biomimetic analog-based adhesive system inhibited the activities of dentin proteases immediately after treatment. Additionally, the proteolytic activity on the affected dentin resembled that of the SD. In conclusion, no HA formed in the demineralized SD and CAD although there were calcium and phosphate deposits. The experimental adhesive system inhibited dentin proteases. The present study uses a new approach to investigate the hybrid layer behavior in dentin. The experimental adhesive system was synthesized and used on sound and affected-caries dentin as the substrate to reproduce real clinical conditions.
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http://dx.doi.org/10.1002/jemt.23557DOI Listing
December 2020

Fabrication and characterization of remineralizing dental composites containing hydroxyapatite nanoparticles.

J Mech Behav Biomed Mater 2020 09 28;109:103817. Epub 2020 Apr 28.

Analytical Laboratory of Restorative Biomaterials - LABiom-R, School of Dentistry, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil. Electronic address:

The aim of this study was to fabricate and characterize dental composites containing hydroxyapatite nanoparticles (HApNPs). Four dental composites were produced from the same organic matrix (70 wt% Bis-GMA and 30 wt% TEGDMA), with partial replacement of BaBSi particles (65 wt%) by HApNPs in the following concentrations (wt%): E0 (0) - control, E10 (10), E20 (20) and E30 (30). Ca and PO release was evaluated in solutions with different pHs (4, 5.5, and 7) using atomic emission spectroscopy with microwave-induced nitrogen plasma while the enamel remineralization potential was evaluated in caries-like enamel lesions induced by S. mutans biofilm using micro-CT. The following properties were characterized: degree of conversion (DC%), microhardness (KHN), flexural strength (FS), elastic modulus (EM) and translucency (TP). The higher the HApNPs content, the higher the Ca and PO release. The ions release was influenced by pH (4 > 5.5 > 7) (p < 0.05). All composites loaded with HApNPs were able to remineralize the enamel (E30 = E20 > E10) (p < 0.05). Contrarily, E0 was not able of recovering the enamel mineral loss. E0 and E10 presented highest DC%, while E20 and E30 showed similar and lowest DC%. KHN and FS were decreased with the addition of HApNPs, while EM was not influenced by the incorporation of HApNPs. E10 presented statistically similar TP to E0, while this property decreased for E20 and E30 (p < 0.05). Incorporation of HApNPs into dental composites promoted enamel remineralization, mainly at potentially cariogenic pH (= 4), while maintained their overall performance in terms of physicomechanical properties.
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http://dx.doi.org/10.1016/j.jmbbm.2020.103817DOI Listing
September 2020

Characterization and Antibacterial Effect of an Experimental Adhesive Containing Different Concentrations of Proanthocyanidin.

J Adhes Dent 2020 ;22(2):139-147

Purpose: To evaluate the degree of conversion (DC%), water sorption (Sp), solubility (Sl), dentin bond strength (μTBS) (immediate and after 12 months of storage), and the antibacterial effect of an experimental adhesive containing different concentrations (%) of proanthocyanidin (PA): 0, 1%, 2%, 4.5%, and 6% (PA0, PA1%, PA2%, PA4.5% and PA6%, respectively).

Materials And Methods: DC% was measured by FT-IR and the Sp and Sl were determined based on the ISO 4049 specification. For μTBS, resin composite buildups were constructed incrementally and specimens (n = 8) were sectioned to obtain sticks (1 mm2). The μTBS was evaluated after 24 h and 12 months of water storage at 37°C. The failure mode was analyzed. The antibacterial effects were evaluated by analyzing the bacterial growth (S. mutans) (n = 5) and antibiofilm activity (n = 5) of the adhesives by spectrophotometry.

Results: The incorporation of PA did not affect the Sp, Sl, or DC%. Immediate μTBS was similar for all groups. After 12 months, PA4.5% presented significantly higher μTBS than PA0, while the other groups did not differ from PA0 and PA4.5%. Groups PA0 and PA1% underwent significant reduction in μTBS. In the experimental groups PA2%, PA4.5% and PA6%, μTBS was maintained after storage. All groups showed antibacterial activity.

Conclusion: Incorporation of 2%, 4.5%, and 6% PA maintained the dentin μTBS after 12-month storage, without affecting the Sp, Sl, or DC% of experimental adhesives. PA4.5% presented higher μTBS values than PA0 after 12 months. The adhesive presented antibacterial effect irrespective of PA concentration.
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http://dx.doi.org/10.3290/j.jad.a44280DOI Listing
April 2020

Self-cured resin modified by quaternary ammonium methacrylates and chlorhexidine: Cytotoxicity, antimicrobial, physical, and mechanical properties.

Dent Mater 2020 01 14;36(1):68-75. Epub 2019 Nov 14.

Department of Prosthodontics, School of Dentistry, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil. Electronic address:

Objective: To evaluate the addition of dimethylaminohexadecyl methacrylate (DMAHDM) and chlorhexidine diacetate on cytotoxicity, antimicrobial activity, physical, and mechanical properties of a self-cured resin.

Methods: 132 disk-shaped and 48 rectangular specimens were divided into four experimental groups as described: Control Group (CG - no addition), dCHX (1%), DMAHDM (5%), and DMAHDM+dCHX (5%+1%). The biofilm viability, flexural strength (FS - ISO 20795-1:2013), surface roughness (SR), and color stability (ΔE) were analyzed after being stored for 4 weeks in distilled water and immersed for 72h in coffee. Cytotoxicity was measured after 24h, 3, and 7 days of elution using an MTT test on L929 cells (ISO 10993-5:2009). SR and ΔE were measured by a contact profilometer and a spectrophotometer using the CIELab parameter. Data were submitted to ANOVA and Bonferroni's/Tukey's tests (p≤0.05).

Results: Significant antimicrobial activity against Streptococcus mutans and Candida albicans was detected in all groups when compared to the CG (p<0.05). Only the dCHX group, in 24h of elution, demonstrated no cytotoxicity effects. There was a statistical difference for FS on the tested groups (p<0.05). No differences were detected in the initial roughness' measurements among the groups (p>0.05). However, after storage and immersion in coffee, the groups containing DMAHDM presented with rougher surfaces and significantly lower color stability compared to the control (p<0.05).

Significance: The addition of dCHX and DMAHDM in self-cured resin presented antimicrobial properties; however, cytotoxicity, physical, and mechanical properties were compromised.
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http://dx.doi.org/10.1016/j.dental.2019.10.007DOI Listing
January 2020

Remineralizing potential of dental composites containing silanized silica-hydroxyapatite (Si-HAp) nanoporous particles charged with sodium fluoride (NaF).

J Dent 2019 11 14;90:103211. Epub 2019 Oct 14.

Analitical Laboratory of Restorative Biomaterials - LABiom-R, School of Dentistry, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil. Electronic address:

Objectives: To synthesize and evaluate the enamel remineralizing potential of dental composites containing silanized silica-hydroxyapatite (Si-HAp) nanoporous particles charged with sodium fluoride (NaF).

Methods: Si-HAp particles were synthesized using a solid-state method. Dental composites were prepared by incorporating 70 wt.% of Si-HAp particles into a 70/30 wt.% Bis-GMA/TEGDMA organic matrix. Four dental composites were produced: SilF, Sil, F, and NT (nontreated). For SilF and F, Si-HAp particles were previously treated with 10% NaF (F). Afterwards, SilF and Sil composites had their particles silanized (Sil) with α-methacryloxypropyl-1-trimethoxysilane (α-MPS). The remineralizing potential was evaluated in caries-like enamel lesions induced byS. mutans biofilm for seven days and after pH-cycling for fifteen days using X-ray microtomography (micro-CT). Z350 was used as a commercial control for remineralizing potential evaluation Degree of conversion (DC%), flexural strength (FS), and Knoop hardness (KHN) were characterized. Data were analyzed using one-way ANOVA and Tukey's HSD post-hoc test (α = 0.05).

Results: F presented the highest enamel remineralizing potential, followed by SilF. Alternatively, Sil and NT were not capable of totally recovering the enamel mineral loss. NT showed the highest DC%, followed by Sil, F, and SilF. Sil and NT showed the highest FS when compared to SilF and F. No statistical significance in KHN was found among the composites.

Conclusions: Dental composites with Si-HAp nanoporous particles charged with NaF presented a remineralizing potential for human enamel. However, this ability underwent a subtle reduction after particle silanization.

Clinical Significance: Si-HAp nanoporous particles charged with NaF may be an alternative for producing dental composites with an improved remineralizing potential for enamel affected by caries.
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http://dx.doi.org/10.1016/j.jdent.2019.103211DOI Listing
November 2019

Experimental composites containing quaternary ammonium methacrylates reduce demineralization at enamel-restoration margins after cariogenic challenge.

Dent Mater 2019 08 13;35(8):e175-e183. Epub 2019 Jun 13.

Faculdade de Odontologia, Universidade Federal Fluminense, Niterói, RJ, Brazil. Electronic address:

Objective: This study evaluated the influence of experimental composites containing quaternary ammonium monomers (QAM) at different concentrations and alkyl chains on demineralization at enamel-composite margins after cariogenic challenge.

Methods: Standardized 4×4mm cavities were cut into 35 bovine enamel blocks, which were randomly divided into seven groups (n=5) and restored with the following experimental composites and commercial materials: (G12.5) - 5% dimethylaminododecyl methacrylate (DMADDM) with a 12-carbon alkyl chain (G12.10) - 10% DMADDM, (G16.5) - 5% dimethylaminohexadecyl methacrylate (DMAHDM) with a 16-carbon alkyl chain (G16.10) - 10% DMAHDM, (CG) - control group (without QAM), (GZ250) - commercial composite (Filtek Z250), and (GIC) - glass ionomer cement (Maxxion R). After restorative procedures, initial microhardness was measured and experimental composites were subjected to Streptococcus mutans biofilm formation for 48h. After cariogenic challenge, the samples were washed and microhardness was reassessed. A 3D non-contact profilometer was used to determine surface roughness and enamel demineralization was assessed by micro-CT. Microhardness results were analyzed by the Kruskal-Wallis and Mann-Whitney tests and micro-CT results were analyzed by Tukey's HSD test (95% confidence interval).

Results: None of the materials could prevent mineral loss at the enamel-restoration margins. The addition of 10% DMAHDM yielded the lowest, albeit statistically significant, mineral loss (p<0.05). 3D non-contact profilometry showed enamel surface roughness modification after biofilm exposure. The CG had the highest roughness values. Micro-CT analysis revealed mineral loss, except for GIC.

Significance: The addition of 10% QAM with a 16-carbon chain in experimental composites reduced mineral loss at the enamel-restoration margins after cariogenic challenge.
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http://dx.doi.org/10.1016/j.dental.2019.05.021DOI Listing
August 2019

Model resin composites incorporating ZnO-NP: activity against S. mutans and physicochemical properties characterization.

J Appl Oral Sci 2018 7;26:e20170270. Epub 2018 May 7.

Laboratório Analítico de Biomateriais Restauradores- LABiom-R, Faculdade de Odontologia, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brasil.

Although resin composites are widely used in the clinical practice, the development of recurrent caries at composite-tooth interface still remains as one of the principal shortcomings to be overcome in this field. Objectives To evaluate the activity against S. mutans biofilm of model resin composites incorporating different concentrations of ZnO-nanoparticles (ZnO-NP) and characterize their physicochemical properties. Materials and Methods Different concentrations of ZnO-NP (wt.%): E1=0, E2=0.5, E3=1, E4=2, E5=5 and E6=10 were incorporated into a model resin composite consisting of Bis-GMA-TEGDMA and barium borosilicate particles. The activity against S. mutans biofilm was evaluated by metabolic activity and lactic acid production. The following physicochemical properties were characterized: degree of conversion (DC%), flexural strength (FS), elastic modulus (EM), hardness (KHN), water sorption (Wsp), water solubility (Wsl) and translucency (TP). Results E3, E4, E5 and E6 decreased the biofilm metabolic activity and E5 and E6 decreased the lactic acid production (p<0.05). E6 presented the lowest DC% (p<0.05). No significant difference in FS and EM was found for all resin composites (p>0.05). E5 and E6 presented the lowest values of KHN (p<0.05). E6 presented a higher Wsp than E1 (p<0.05) and the highest Wsl (p<0.05). The translucency significantly decreased as the ZnO- NP concentration increased (p<0.05). Conclusions The incorporation of 2 - 5 wt.% of ZnO-NP could endow antibacterial activity to resin composites, without jeopardizing their physicochemical properties.
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http://dx.doi.org/10.1590/1678-7757-2017-0270DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5933836PMC
May 2018

Influence of biofilm formation on the mechanical properties of enamel after treatment with CPP-ACP crème.

Braz Oral Res 2017 Nov 27;31:e84. Epub 2017 Nov 27.

Universidade Federal Fluminense - UFF, School of Dentistry, Niterói, RJ, Brazil.

The study aimed to investigate the effects of bacterial biofilms on changes in the surface microhardness of enamel treated with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with and without fluoride. Human enamel blocks with incipient caries-like lesions were divided into four groups of 13: G1: Saliva (Control); G2: fluoride dentifrice (Crest™, 1100 ppm as NaF); G3: CPP-ACP (MI Paste; Recaldent™); and G4: CPP-ACPF (MI Paste Plus; Recaldent™ 900 ppm as NaF). The specimens were soaked in demineralizing solution for 6 h and remineralized in artificial saliva for 18 h alternately for 10 days. The dentifrice was prepared with deionized water in a 1 : 3 ratio (w/w) or applied undiluted in the case of the CPP-ACP group. The surface microhardness (SMH) was evaluated at baseline, after artificial caries, after pH cycling and treatment with dentifrices, and after incubation in media with Streptococcus mutans for biofilm formation. The biofilms were exposed once a day to 2% sucrose and the biofilm viability was measured by MTT reduction. The percentage of change in surface microhardness (%SMHC) was calculated for each block. The data were analyzed by nonparametric test comparisons (α = 0.05). The %SMHC values observed in G2 were different from those of G1, G3, and G4 (p < 0.05). After biofilm formation, %SMHC was positive in G2 and G4 when compared to G1 and G3, but resistance to demineralization after biofilm formation was similar in all groups. In conclusion, the presence of biofilms did not influence the treatment outcomes of anticaries products.
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http://dx.doi.org/10.1590/1807-3107BOR-2017.vol31.0084DOI Listing
November 2017

Antibiofilm properties of model composites containing quaternary ammonium methacrylates after surface texture modification.

Dent Mater 2017 10 16;33(10):1149-1156. Epub 2017 Aug 16.

School of Dentistry, Federal Fluminense University - UFF, Niterói, RJ, Brazil; Nucleus for Dental Biomaterials Research, UVA-Veiga de Almeida University, Rio de Janeiro, RJ, Brazil; School of Dentistry, UNIVERSO-Salgado de Oliveira University, Niterói, RJ, Brazil. Electronic address:

Objective: Investigate antimicrobial properties and surface texture of model composites with different concentration and alkyl chain length of quaternary ammonium monomers (QAS).

Methods: Monomers derived from QAS salts with alkyl chain lengths of 12 carbons ((dimethylaminododecyl methacrylate) DMADDM) and 16 carbons (dimethylaminohexadecyl methacrylate-DMAHDM) were obtained from the reactions of their respective organo-halides with the tertiary amine 2-(dimethylamino)ethyl methacrylate (DMAEMA). DMADDM and DMAHDM were incorporated into model composite in concentrations of 5 or 10%, resulting the following groups: G12.5 (DMADDM 5%), G12.10 (DMADDM 10%), G16.5 (DMAHDM 5%), G16.10 (DMAHDM 10%) and GC (control). Biofilm viability, lactic acid production and surface roughness were analysed 24h after samples preparation (initial), repeated after toothbrush abrasion and after polishing simulation. Data were submitted to ANOVA and Tukey's test (p≤0.05).

Results: The longer the molecular chain size of QAS and the higher its concentration (G16.10), the lower was the viability and the production of lactic acid by the biofilm. No differences were detected in initial roughness' measurements among groups. However, after abrasion, there was an increase of biofilm viability and lactic acid production. Composites containing QAS presented rougher surfaces compared to the CG. After polishing, biofilm viability and surface roughness were statistically similar for all groups. Nevertheless, DMAHDM at 10% showed reduction in lactic acid production.

Significance: Chain length and concentration of QAS influenced biofilm development and production of lactic acid. Longer chains and higher concentrations of QAS promoted better antimicrobial properties. Changes in surface texture caused by abrasion, decreased antibiofilm properties.
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http://dx.doi.org/10.1016/j.dental.2017.07.010DOI Listing
October 2017

Role of Candida species from HIV infected children in enamel caries lesions: an in vitro study.

J Appl Oral Sci 2017 Jan-Feb;25(1):53-60

Universidade Federal do Rio de Janeiro, Faculdade de Odontologia, Departamento de Odontopediatria e Ortodontia, Rio de Janeiro, RJ, Brasil.

Objectives: This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel.

Material And Methods: Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%.

Results: TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation.

Conclusion: Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro.
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http://dx.doi.org/10.1590/1678-77572016-0021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5289400PMC
April 2017

Candida species from oral cavity of HIV-infected children exhibit reduced virulence factors in the HAART era.

Microb Pathog 2017 Jan 29;102:74-81. Epub 2016 Nov 29.

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro (UFRJ), Brazil.

This study aimed to assess, in vitro, the biofilm viability and the phospholipase and protease production of Candida spp. from the saliva of HIV infected children and healthy controls, and to correlate the results with the use of medical data. A total of 79 isolates were analyzed: 48 Candida albicans isolates (33/15) and 20 Candida parapsilosis sensu lato complex isolates (12/8) (from HIV/control patients, respectively), and 8 Candida krusei, 1 Candida tropicalis, 1 Candida dubliniensis and 1 Candida guilliermondii from HIV patients. The XTT (2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-Carboxanilide) reduction assay analyzed the biofilm viability. Phospholipase and protease assays were performed using the egg yolk and Bovine Serum Albumin agar plate methods, respectively. All isolates were able to form biofilm with cell viability. Quantitatively, Candida isolates from both groups presented a similar ability to form biofilm (p > 0.05). The biofilm viability activity was higher in C. albicans isolates than in non-albicans Candida isolates (p < 0.05) for both groups. Phospholipase activity was detected in 32 isolates (40.5%) and it was significantly higher in the HIV group (p = 0.006). Protease activity was detected in 66 isolates (84.8%) and most of them were relatively/very strong producers. No statistical association with medical data was found in the HIV group. Although Candida spp. isolates from HIV-positive children presented higher phospholipase production, in vitro they exhibited reduced virulence factors compared to isolates from healthy individuals. This finding may enlighten the role played by immunosuppression in the modulation of Candida virulence attributes.
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http://dx.doi.org/10.1016/j.micpath.2016.11.020DOI Listing
January 2017

Demineralizing potential of dental biofilm added with Candida albicans and Candida parapsilosis isolated from preschool children with and without caries.

Microb Pathog 2016 Nov 7;100:51-55. Epub 2016 Sep 7.

Departamento de Odontopediatria e Ortodontia, da Faculdade de Odontologia da Universidade Federal do Rio de Janeiro, Brazil. Electronic address:

This study aimed to investigate the demineralizing potential of dental biofilm added of Candida albicans (CA) and Candida parapsilosis (CP), isolated from preschoolers with and without caries. Bovine enamel blocks (n = 48), with initial hardness = 341.50 ± 21,83 kg/mm were fixed in 24 well plates containing culture media. A pool of children saliva (PHS) was the inoculum for biofilm formation in the presence or absence of isolated CA or CP in accordance with each group (G n = 8): G1 - PHS; G2 - PHS + CA isolated from children with caries; G3 - PHS + CP isolated from children with caries; G4 - PHS + CA isolated from children without caries; G5 - PHS + CP isolated from children without caries; and G6 - blank control. The plates were incubated at 37 °C for 5 days, with daily changes of culture media. The microhardness loss percentage (MHL%) of the blocks was calculated, taking in account the hardness values before and after the experiment. Dental biofilm became more cariogenic, independently of the isolated Candida species. The highest MHL% was observed in G4 (85.90 ± 8.72%) and G5 (86.13 ± 6.74%) compared to the others (p < 0.001): G1 (34.30 ± 14,30%) < G2 (59.40 ± 10.56%) and G3 (65.80 ± 6.36%) < G6 (13.68 ± 4.86%) (p < 0.001). C. albicans and C. parapsilosis isolates induced the demineralization of the dental enamel.
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http://dx.doi.org/10.1016/j.micpath.2016.09.003DOI Listing
November 2016

Association of Species Isolated From the Dental Plaque of HIV-infected Children and Prevalence of Early Carious Lesions.

J Dent Child (Chic) 2016 Sep;83(3):139-145

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.

Purpose: The purposes of this study were to: (1) quantify and identify Candida species (spp.) in the dental plaque of children infected with the human immunodeficiency virus (HIV) and compare with noninfected children; and (2) determine the association of Candida spp. with the presence of caries.

Methods: Seventy HIV-infected and 55 non-HIV-infected three- to 12-year-old children were examined to determine caries prevalence. After a visual inspection, supragingival plaque was collected from the cervical region using standard dental curettes. The material was transferred to microtubes and submitted for analysis to identify and quantify the presence of Candida spp.

Results: Candida spp. were more prevalent in the HIV-infected group (72.9 percent) than in the control group (20 percent), and the most prevalent specie was Candida albicans. Caries was found in 72.9 percent of the HIV-infected group and in 58.2 percent of the control group, but a significant difference was only found in the presence of active white spot lesions between the groups.

Conclusions: The dental plaque of HIV-infected children was colonized by Candida species to a much greater extent than that of non-HIV-infected children, and this colonization was significantly associated with the prevalence of early carious lesions in enamel.
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September 2016

Is dental caries experience increased in HIV-infected children and adolescents? A meta-analysis.

Acta Odontol Scand 2015 12;73(7):481-7. Epub 2015 Mar 12.

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro , Rio de Janeiro , Brazil.

Objective: To undertake a systematic review to assess if HIV-infected children and adolescents have an increased dental caries experience.

Methods: A search of MEDLINE, BIREME, EMBASE, GOOGLE SCHOLAR, SIGLE (Grey Literature) and reference lists of included studies was carried out. To be eligible the studies had to present HIV-infected and non-infected children/adolescents between 0-18 years old. To assess the methodological quality, the studies were categorized in scores from 'A' to 'C'. To perform a meta-analysis a random effect model was used with 95% confidence intervals and two distinct sub-group analyses were carried out in terms of caries progression: data for cavitated and non-cavitated lesions (sub-group 1) and data only for cavitated lesions (sub-group 2).

Results: Five studies fulfilled the selection criteria. Four studies (two ranked A and two B in the quality assessment) revealed higher caries scores in primary teeth in the HIV-infected patients with mean dmft/dmfs scores of 3.8-4.1/7.8-11.0 compared to the control group 1.5-2.4/3.4-5.1. No differences in caries index were found for permanent dentition. The meta-analysis excluded caries data of permanent teeth and showed a significant association between caries experience in primary dentition and HIV infection considering cavitated and non-cavitated lesions (OR = 2.33, 95% CI = 1.48-3.68) or only cavitated lesions (OR = 2.98, 95% CI = 1.59-5.59).

Conclusion: Evidence exists that suggests HIV-infected children/adolescents have an increased caries experience in primary dentition.
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http://dx.doi.org/10.3109/00016357.2014.958874DOI Listing
February 2016

Caries prevention and adhesiveness of restorative materials submitted to cariogenic mixed biofilm.

Gen Dent 2014 Sep-Oct;62(5):71-4

This in vitro study evaluated the mechanical properties of different restorative materials submitted to cariogenic conditions with induced mixed biofilm. Extracted bovine incisors (n = 108) were divided into 3 groups (n = 36) [Group 1, resin; Group 2, glass ionomer cement (GIC); and Group 3, resin-modified GIC] and were bonded on a previously prepared enamel surface with a 25 mm² area delimited with nail varnish. Each group was then further subdivided into 3 groups and tested for shear bond strength and effectiveness in caries protection. Groups 1A-3A were tested immediately after bonding, Groups 1B-3B were tested after 5 days in brain heart infusion media, and Groups 1C-3C were tested after 5 days under cariogenic conditions with mixed biofilm. The mixed biofilm system was composed of Streptococcus mutans and Candida albicans in order to artificially create white spot lesions (WSLs). Group 1 presented the most samples with WSLs, whereas Groups 2 and Group 3 presented the highest preventive effect (P < 0.05) across all subgroups. The mean bond strengths were highest in Group 1 across all subgroups (P < 0.05). The majority of the specimens in the Group 1 subgroups presented mixed and cohesive fractures, whereas Groups 2 and 3 subgroups presented the largest amount of adhesive fractures.
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July 2016

Effect of the secretory leucocyte proteinase inhibitor (SLPI) on Candida albicans biological processes: a therapeutic alternative?

Arch Oral Biol 2014 Sep 13;59(9):928-37. Epub 2014 May 13.

Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address:

Objectives: The aim of this study was to evaluate the effect of SLPI on the growth and biological processes of Candida albicans.

Methods: Two C. albicans strains were used in this study, a clinical isolate resistant to fluconazole (PRI) and a reference strain ATCC 24433. The minimal inhibitory concentration (MIC) was determined according to the CLSI methodology. The influence of SLPI on secreted serine proteinase activities (SSP) was measured by the cleavage of specific substrate, and surface hydrophobicity was determined by the aqueous-hydrocarbon biphasic separation method. Flow cytometry was performed to investigate receptors for SLPI and variations in the cell wall mannoprotein expression. Interaction between yeast and epithelium was assessed using the MA-104 cells lineage. Ultrastructure was analyzed by transmission electron microscopy (TEM).

Results: MIC values were calculated as 18 and 18.9μM for the PRI and ATCC 24433, respectively. SSP activity was reduced by 48.8% by 18μM of SLPI and cell surface hydrophobicity increased by 11.1%. Flow cytometry suggest the existence of SLPI binding sites on the surface of the yeast. Results showed a reduction in the expression of mannoproteins in 20.8% by the cells treated with 80μM of SLPI, and 18μM reduced the adhesion of yeasts to mammalian cells in 60.1%. TEM revealed ultrastructural changes in cells treated with 80μM of SLPI, such as the presence of membrane-like structures within the cytoplasm.

Conclusions: SLPI exerts a significant influence on C. albicans viability and biological processes. Considering its constitutive and physiologic features, SLPI may become a promising tool for the development of new methodologies for the treatment and control of candidiasis.
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http://dx.doi.org/10.1016/j.archoralbio.2014.05.007DOI Listing
September 2014

Salivary lactoferrin in HIV-infected children: correlation with Candida albicans carriage, oral manifestations, HIV infection and its antifungal activity.

Arch Oral Biol 2014 Aug 21;59(8):775-82. Epub 2014 Apr 21.

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.

Objectives: This study aimed to evaluate the concentration of lactoferrin in the saliva of HIV infected and healthy children and analyze the associations between lactoferrin levels, Candida sp. colonization, oral manifestations and medical data. Also, the antifungal ability of lactoferrin to inhibit the growth of Candida albicans isolated from saliva of these children was investigated in vitro.

Subjects And Methods: Saliva was collected from 70 HIV-infected and 50 healthy children, followed by oral manifestation assessments. The salivary lactoferrin was quantified using an ELISA Kit. The salivary samples were cultured and the Candida spp. colonies counted and then identified by sugar assimilation and fermentation. The antifungal activity of lactoferrin was analyzed in vitro with 10 isolates of C. albicans from each group.

Results: The HIV infected children (mean age 9.8 ± 2.8) had higher lactoferrin levels (median 6.13 μg/ml (3.58-7.89)) and were colonized three times more by Candida sp. than the control group (mean age 9.4 ± 2.4) (median 5.74 μg/ml (3.12-6.86)) (p=0.003). Statistical associations were found considering the salivary lactoferrin levels and Candida sp. and oral manifestations between the groups. No associations between lactoferrin concentrations and oral manifestations, immunosuppression, presence of AIDS and use of HAART were observed in the HIV group. The percentage of dead C. albicans due to lactoferrin was inversely proportional to C. albicans cell density for both groups (p<0.001).

Conclusions: HIV-infected children have higher concentrations of lactoferrin and it was associated with Candida sp. colonization but no association with medical data was found. Also, both groups showed similar lactoferrin antifungal activity.
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http://dx.doi.org/10.1016/j.archoralbio.2014.04.010DOI Listing
August 2014

Sialoglycoproteins in morphological distinct stages of Mucor polymorphosporus and their influence on phagocytosis by human blood phagocytes.

Mycopathologia 2013 Oct 14;176(3-4):183-9. Epub 2013 Aug 14.

Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho 373, sala 050, Rio de Janeiro, RJ, CEP: 21941-902, Brazil,

The possible role of sialic acids in host cells-fungi interaction and their association with glycoproteins were evaluated using a clinical isolate of the dimorphic fungus Mucor polymorphosporus. Lectin-binding assays with spores and yeast cells denoted the presence of surface sialoglycoconjugates containing 2,3- and 2,6-linked sialylglycosyl groups. Western blotting with peroxidase-labeled Limulus polyphemus agglutinin revealed the occurrence of different sialoglycoprotein types in both cell lysates and cell wall protein extracts of mycelia, spores, and yeasts of M. polymorphosporus. Sialic acids contributed to the surface negative charge of spores and yeast forms as evaluated by adherence to a cationic substrate. Sialidase-treated spores were less resistant to phagocytosis by human neutrophils and monocytes from healthy individuals than control (untreated) fungal suspensions. The results suggest that sialic acids are terminal units of various glycoproteins of M. polymorphosporus, contributing to negative charge of yeasts and spore cells and protecting infectious propagules from destruction by host cells.
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http://dx.doi.org/10.1007/s11046-013-9692-6DOI Listing
October 2013

Dental needs and management of children with special health care needs according to type of disability.

J Dent Child (Chic) 2012 Sep-Dec;79(3):165-9

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Brazil.

Purpose: The purpose of this study was to investigate the dental needs and management of special health care needs children in Rio de Janeiro, Brazil, according to the type of disability.

Methods: Records of 428 0- to 19-year-old patients who received dental treatment at the Patients Special Care Needs Clinic (Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro) from 1996-2009 were analyzed. Information about the type of disability, use of medication, dental exam findings, management during treatment, dental treatment performed, and follow-up examinations were collected. Children were divided into 2 groups: those with medical conditions and those with intellectual disability.

Results: Patients with medical conditions used more medications and were older than those with intellectual disability. The most common dental treatments received were dental restorations (63%) and extractions (47%). There was no association between the type of disability and dental treatment needed. Children with intellectual disability were 3 times more likely to need general anesthesia and 7 times more likely to need physical restraint for dental care than the other group.

Conclusions: Children with intellectual disability have a greater chance of requiring advanced management techniques during dental treatment. The development of effective oral health programs is recommended as well as a specific education program for their parents.
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August 2013

Biofilm of Candida albicans from oral cavity of an HIV-infected child: challenge on enamel microhardness.

Oral Surg Oral Med Oral Pathol Oral Radiol 2013 Apr 4;115(4):500-4. Epub 2013 Feb 4.

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.

Objective: The aim of this study was to analyze the effect of C. albicans on enamel microhardness in vitro.

Study Design: Candida albicans was isolated from the oral mucosa (M) and dentin carious lesion (D) of an HIV+ child. Three groups of 12 enamel blocks each were placed in Petri plates (yeast carbon base agar/1% bovine serum albumin): G1, exposed to biofilm formed by C. albicans from M; G2, exposed to biofilm formed by C. albicans from D; G3, no biofilm. Three enamel blocks from each group were removed on days 3, 5, 8, and 10 after biofilm formation to measure the cross-sectional Knoop microhardness (CSMH) of the enamel areas, exposed and not exposed to biofilm.

Results: CSMH decreased in G1 and G2: in G1 on day 5, and in G2 on day 3 (analysis of variance: P < .05; Mann-Whitney test: P < .05), with a similar mean percentage reduction for both groups.

Conclusions: Candida albicans can reduce enamel microhardness in vitro.
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http://dx.doi.org/10.1016/j.oooo.2012.11.003DOI Listing
April 2013

The oral health of HIV-infected Brazilian children.

Int J Paediatr Dent 2013 Sep 2;23(5):359-65. Epub 2012 Nov 2.

Pediatric Dentistry and Cariology, Department of Specific Formation, Faculty of Dentistry, Fluminense Federal University, Nova Friburgo, Brazil.

Background: The number of HIV-infected people has increased almost continuously. Paediatric dentists should be concerned about the oral findings in HIV-infected children and their aetiologic factors, to promote adequate treatment.

Aim: To present the oral health aspects of Brazilian HIV-infected children and to verify the aetiological factors.

Design: A cross-sectional study was conducted with HIV-infected children. During the medical appointments, children were submitted to visual-tactile exams of oral soft tissues and teeth. All parents answered questions in a structured interview. Data were analysed using the SPSS, release 10.0 (Chicago, IL, USA).

Results: Of the 57 children examined, 39 (69.6%) presented one or more oral soft tissue manifestations. More than a half suffered from gingivitis and only 12.5% had no visible dental biofilm. A high prevalence of dental surfaces with active carious lesions was observed; mean DMFS-m and dmfs-m scores were 5.41 ± 5.61 and 16.77 ± 19.52, respectively. Caries activity and gingivitis were correlated with the presence of mature dental biofilm.

Conclusions: Prevalence of soft tissue lesions, dental caries and gingivitis in HIV-infected children was high and correlated to lack of satisfactory oral hygiene habits, suggesting the need of therapeutic programmes that allow these children to recover their oral health.
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http://dx.doi.org/10.1111/ipd.12008DOI Listing
September 2013

Differential collagenolytic activity of Candida albicans isolated from oral mucosa and dentinal carious lesions of HIV-infected children.

Oral Surg Oral Med Oral Pathol Oral Radiol 2012 Mar;113(3):378-83

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

Objective: The aim of this study was to compare type I collagen degradation by Candida albicans isolated from oral mucosa (M) and cavitated active dentinal caries (CAD) of HIV-infected children.

Study Design: To verify the proteolytic activity, the specimens were cultivated in brain-heart infusion medium and the supernatants were incubated in the presence or absence of type I collagen at 37°C for 12 hours and analyzed using 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Intensity of the bands on the gels was assessed by densitometric analysis using a scanner and images analyzed with software from Kodak Digital Science EDAS 120.

Results: Supernatants of all the C. albicans degraded type I collagen: that from M, on average, by 38.3% (SD 21.67) and that from CAD by 54% (SD 25.94; Wilcoxon test: P < .05). Predisposing factors had no association with the percentage of type I collagen degradation (Mann-Whitney test: P > .05).

Conclusions: Candida albicans from different sites of the oral cavity of HIV-infected children has proteolytic activity for type I collagen.
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http://dx.doi.org/10.1016/j.oooo.2011.09.006DOI Listing
March 2012

Severe oligodontia and dental anomalies in a child with a history of multiple natal teeth: An eight-year retrospective.

Gen Dent 2011 Nov-Dec;59(6):e248-50

Department of Pediatric Dentistry and Orthodontics, Federal University of Rio de Janeiro, Brazil.

This article reports the case of a boy born with 11 natal teeth who had many alterations in his permanent dentition. In this case, 22 teeth were missing and a shape anomaly was detected in eight teeth. The treatment consisted of prosthetic rehabilitation and follow-up of teeth eruption and jaw growth.
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July 2012

Bruxism control in a child with cerebral palsy.

ISRN Dent 2011 1;2011:146915. Epub 2010 Dec 1.

Department of Paediatric Dentistry and Orthodontics, School of Dentistry, Federal University of Rio de Janeiro, Rio de Janeiro, 21941-901/RJ, Brazil.

Cerebral palsy (CP) is one of the most severe childhood disabilities due to a lesion in the developing brain. Oral conditions often observed in this pathogenic are a tendency for the delayed eruption of permanent molars, higher percentages of malocclusion and parafunctional habits, including bruxism. The significance of oral conditions observed in CP patients demonstrates the need for intensive home and professional care for these individuals. This paper presents a 7-year-old boy, with cerebral palsy, severe mental retardation, who had high abrasion wear of the primary teeth related to bruxism. Dental care was carried out under oxide-induced sedation, and management of the bruxism was achieved after the use of a resin acrylic protective appliance fixed on both sides of the mandibula. The treatment performed offered efficiency advantages, was clinically viable, and should be a valuable option to practitioners considering appliance therapy to control parafunctional behavior.
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http://dx.doi.org/10.5402/2011/146915DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3170074PMC
November 2011

Use of chlorhexidine gel (0.2%) to control gingivitis and candida species colonization in human immunodeficiency virus-infected children: a pilot study.

Pediatr Dent 2011 Mar-Apr;33(2):153-7

Department of Pediatric Dentistry and Orthodontics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

Purpose: The purpose of this study was to evaluate chlorhexidine to control gingivitis and Candida species (spp.) in children infected with the human immunodeficiency virus (HIV) and their acceptance of the therapy.

Methods: Twenty-six HIV+ children were selected, and oral exam-established biofilm, gingival indexes, and stimulated saliva were collected for Candida ssp. identification. The children brushed their teeth for 21 days with chlorhexidine gel (0.2%). Salivary samples, biofilm, and gingival indexes were collected after 21-days and again 35 days after ceasing gel use. The children answered a questionnaire about the therapy.

Results: All children tested positive for Candida and gingivitis. After 21 days, Candida counts and gingivitis decreased in 25 and 26 children, respectively. Mean reduction was approximately 68% for Candida spp. and 74% for gingivitis. Thirty-five days after discontinuing gel use, gingivitis and Candida spp. increased in 13 and 16 patients, respectively. Considering the Candida spp., the heavy growth was lower in the first re-evaluation. Candida albicans was the most frequent species. Approximately 85% did not experience inconvenience with the gel, and approximately 48% thought it was good for tooth-brushing.

Conclusion: Chlorhexidine therapy may be an option to treat and pre- vent gingivitis and reduce yeast counts in children infected with HIV.
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September 2011

Inhibitory activity of root canal irrigants against Candida albicans, Enterococcus faecalis and Staphylococcus aureus.

Braz Oral Res 2010 Oct-Dec;24(4):406-12

Federal University of Rio de Janeiro, RJ, Brazil.

The present study evaluated the antimicrobial activity of three root canal irrigants against Enterococcus faecalis, Candida albicans, and Staphylococcus aureus. These microorganisms were incubated in the presence of citric acid (6 and 10%), EDTA (17%), and NaOCl (0.5, 1.0, 2.5, and 5.25%). Agar diffusion tests were performed and redox indicator resazurin was used to evaluate the inhibitory effect of the irrigants on the metabolic activity of these microorganisms. The mean diameters of the inhibition zones for the C. albicans cultures were 11.6 mm (17% EDTA), 5.5 mm (0.5% NaOCl), 12.9 mm (1% NaOCl), 22.1 mm (2.5% NaOCl), and 28.5 mm (5.25% NaOCl). The mean diameters of the inhibition zones for E. faecalis were 2.8 mm (1% NaOCl), 5.4 mm (2.5% NaOCl), and 8.3 mm (5.25% NaOCl). For S. aureus, the mean values were 8.0 mm (17% EDTA), 3.0 mm (1% NaOCl), 8.8 mm (2.5% NaOCl), and 10.0 mm (5.25% NaOCl). Most of the irrigant solutions presented effective antimicrobial activity against C. albicans. A high inhibitory effect on the metabolic activity of E. faecalis was detected when the microorganisms were incubated with 17% EDTA. The same result was reached when S. aureus was incubated in the presence of > 2.5% NaOCl. Altogether, these results indicate that 2.5% and 5.25% NaOCl are microbicides against S. aureus while 0.5% and 1% NaOCl are only microbiostatic against the tested bacteria. The 6% and 10% citric acid as well as 17% EDTA did not affect the viability of any of the assayed microorganisms.
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http://dx.doi.org/10.1590/s1806-83242010000400006DOI Listing
March 2011

Oral Candida colonization and its relation with predisposing factors in HIV-infected children and their uninfected siblings in Brazil: the era of highly active antiretroviral therapy.

J Oral Pathol Med 2010 Feb 22;39(2):188-94. Epub 2009 Dec 22.

Departamento de Odontopediatria e Ortodontia, Faculdade de Odontologia, Universidade Federal do Rio de Janeiro, Brazil.

Objectives: To evaluate predisposing factors such as orofacial manifestations, immunosuppression status and antiretroviral therapy in relation to oral colonization by Candida spp. in Brazilian HIV-infected children and their uninfected siblings in the era of highly active antiretroviral therapy (HAART).

Methods: Whole stimulated saliva was collected from 65 HIV-infected children (HIV+) and 40 uninfected siblings (HIV-), followed by assessment of orofacial manifestation, caries indexes and the number of cavitated dentinal carious teeth (CDT). The salivary samples were cultured and the colonies were counted. After which they were identified by sugar assimilation and fermentation (API 20C). Data was analyzed using chi-square, Mann-Whitney, Spearman tests and logistic regression.

Results: Regarding positive growth, HIV+ presented 80% (52/65) and HIV- 57.5% (23/40) (P = 0.013). Absence of antiretroviral therapy and HAART increased the probability of Candida isolation (P < 0.05). Mean CD4%, immune-status and history of recurrent oral candidiasis (OC) had no influence on Candida isolation. Mixed Candida spp. cultures were observed in HIV+ (40%) and HIV- (52%): C. albicans was more frequently found in both groups, with a higher prevalence in HIV+ (P = 0.05); other non-albicans species were isolated in HIV+ and HIV-. Low prevalence of orofacial manifestations was observed in HIV+ (10.7% of OC). There was an association between means of CDT and Candida growth (P < 0.05) and a positive correlation between number of CDT and Candida cfu-counts in HIV+ and HIV-. Mean CD4% and immune-status had no influence on Candida isolation. Absence of antiretroviral therapy and HAART increased the probability of Candida isolation (P < 0.05).

Conclusions: The HIV infected children had a significantly higher prevalence of oral Candida spp. compared to their uninfected siblings. Absence of HAART and presence of dentinal carious teeth increased significantly Candida spp. colonization in these children.
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http://dx.doi.org/10.1111/j.1600-0714.2009.00857.xDOI Listing
February 2010

Comparison of techniques to evaluate the quantification of Candida spp. in HIV-infected children.

Gen Dent 2009 Jul-Aug;57(4):438-41

Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, RJ, Brazil.

This study sought to compare techniques used to make a quantified evaluation of Candida spp. in children infected with HIV. Twenty-four HIV-infected children (age 3 to 13) were selected. Three sterilized swabs were used for each child: one for the dorsum of the tongue, one for the hard palate mucosa, and one for the right jugal mucosa; each swab was rubbed for 10 seconds and transferred to sterilized test tubes containing 1 mL of 0.9% saline solution. Candida spp. growth was observed in 95.8% of all samples, including 95.7% of tongue samples (Group T), 87.0% of saliva samples, 56.6% of hard palate mucosa samples (Group P), and 47.8% of right jugal mucosa samples (Group J). There was no statistical difference in Candida spp. growth between saliva samples and Group T samples, although both had higher growth compared to Groups P and J (p < 0.05; chi(2)). Regarding the sensitivity of each site for positive Candida spp. growth, Group T samples showed 69.5%, while saliva samples showed 52.2%, Group P samples showed 21.7%, and Group J samples showed 13.04%, with no significant statistical difference between Group T and saliva; however, both were more sensitive than Groups J and P (p < 0.05, chi(2)). It was concluded that whole stimulated saliva and swabbing the tongue were considered satisfactory for measuring Candida spp. in HIV-infected children.
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May 2011