: Pain is one of the most frequent reasons for seeking dental treatment and clinical observations... more : Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid...
The aim of this study was to evaluate the degree of conversion and bond strength of a commercial ... more The aim of this study was to evaluate the degree of conversion and bond strength of a commercial dental adhesive modified by the incorporation of quercetin, resveratrol (RES), and Brazilian red propolis (BRP). Methods: BRP markers were identified using ultra-performance liquid chromatography coupled with a diode array detector, and the antioxidant activity (AAO) of the three substances was analyzed. Single Bond 2 adhesive (3M ESPE) was modified by adding BRP, quercetin, and RES, separately, at 20 μg/mL, 250 μg/mL, and 500 μg/mL, respectively. The degree of conversion (DC) was measured using near-infrared spectroscopy 24 h after photopolymerization. Measurements of the resin-dentin microtensile bond strength (μTBS) were carried out after 1 day and 1 year. Student's t test and ANOVA with Tukey's test were used for data analysis (α ¼ 0.05). Results: The markers daidzein, liquiritigenin, pinobanksin, isoliquiritigenin, formononetin, pinocembrin, and biochanin A were found in the ethanolic extract of BRP. Quercetin, RES, and BRP showed high AAO. The DC of the tested adhesives remained adequate for this category of material, with a slight increase in the DC of adhesives with quercetin and BRP (P > 0.05). Comparisons between μTBS measurements made at 1 day and 1 year showed that, contrary to the control group, μTBS values for all modified adhesives were maintained after 1 year in distilled water (P > 0.05). Conclusions: These findings suggest that quercetin, RES, or BRP might be useful in adhesive dentistry to help improve hybrid layer resistance. Clinical significance: Dentin bonding agents with quercetin, RES, and BRP have potential to increase the longevity of composite restorations.
Journal of Dentistry, Oral Disorders & Therapy, 2015
The most common etiological factor for pulpal and periapical disease is microorganisms. Apical pe... more The most common etiological factor for pulpal and periapical disease is microorganisms. Apical periodontitis is considered as an inflammatory reaction in the peri-apical tissues to the presence of micro-flora and their components within the root canal system. The composition of micro-flora of root canal has been studied extensively over the years and the presence of gram-positive, gramnegative bacteria and their components are considered to be the main reason for endodontic treatment failure. Bacterial components such as Lipopolysaccharide (LPS) and Lipoteichoic Acid (LTA) can enter the peri-apical tissue and initiate the inflammatory process by increasing the level of cytokines. Therefore, this review was done to understand the role of Lipopolysaccharide (LPS), Lipoteichoic acid (LTA) and cytokines in endodontic infection and study their relationship between each other. Data from various resources were gathered and analyzed. The activation pathway and biological effects of cytokines were also studied and it was observed that cytokines especially TNF-α (Tumour Necrosis Factor), IL-1β (Interleukin), IL-6 and IL-8 are up-regulated as a consequence of the immune response generated against the LPS and LTA. Chemokines CXCL2 (Chemokine (C-X-C motif) ligand) and CXCL10 were also shown to have increased level due to the presence of LTA. Cytokines are required to combat the foreign material during an infection, but when the level of cytokines is too high, it can cause injuries to the host itself through peri-apical bone destruction. More studies should be carried out in order to better understand the significance of each cytokine during an endodontic infection and to improve the treatment given for the patients depending on their infection status.
ABSTRACT Successful root canal therapy requires a thorough knowledge of root anatomy and root can... more ABSTRACT Successful root canal therapy requires a thorough knowledge of root anatomy and root canal morphology which may be quiet variable. The significance of internal root canal morphology has been emphasized by studies demonstrating that variations in canal morphology may affect the endodontic outcome. Consequently, in treating each tooth the clinician must assume that complex anatomy occurs often enough to be considered normal. Root dilaceration is one of the variations that may complicate the endodontic therapy. It is important for a clinician to have complete knowledge of internal anatomy relationships, careful interpretation of radiographs; proper access preparation and a detailed exploration of the interior of the tooth to achieve a successful treatment outcome. This paper reports successful endodontic therapy of severe dilaceration of the root of mandibular first molar and bayonet shaped root of maxillary first premolar and highlights the clinical considerations to be followed during the endodontic procedures to get the successful outcome. Indexing terms: Dental pulp cavity. Root canal therapy. Tooth root. RESUMO Um tratamento de canal bem sucedido requer conhecimento profundo da anatomia da raiz dentaria e morfologia do canal radicular, que pode ser variavel. A importância da morfologia interna do canal radicular tem sido enfatizada por estudos que demonstram que as variacoes na morfologia do canal podem afetar o resultado do tratamento endodontico. Consequentemente, no tratamento de cada dente, o clinico deve assumir que uma anatomia complexa ocorre com frequencia suficiente para ser considerada normal. A dilaceracao da raiz dentaria e uma das variacoes que podem complicar o tratamento endodontico. E importante para o clinico ter conhecimento completo das relacoes da anatomia interna, fazer uma interpretacao cuidadosa de radiografias; preparar adequadamente o acesso e realizar uma exploracao detalhada do interior do dente para conseguir um resultado de tratamento bem sucedido. Este artigo relata casos de terapia endodontica bem sucedida de dilaceracao severa da raiz do primeiro molar inferior e de raiz em forma de baioneta de um primeiro pre-molar superior e destaca as consideracoes clinicas a serem seguidas durante os procedimentos endodonticos para se obter exito no tratamento. Termos de Indexacao: Cavidade pulpar. Tratamento do canal radicular. Raiz dentaria.
Background: The implementation of new public healthcare models that stimulate the use of natural ... more Background: The implementation of new public healthcare models that stimulate the use of natural products from traditional medicine, as a so-called integrated medicine, refers to an approach that use best of both conventional medicine and traditional medicine. Propolis is a widely used natural product by different ancient cultures and known to exhibit biological activities beneficial for health. The large number of studies conducted with propolis had shown that its chemical composition differs as a function of the climate, plant diversity and bee species and plays an important role on its therapeutic properties. The aim of this study was to analyse the phytochemical profile of the ethanolic extract of red propolis (EEP) and its fractionation, antioxidant action of EEP and its fractions hexane, cloroform and ethyl acetate and cytotoxic activity of EEP on human tumour cell lines SF-295 (glioblastoma), OVCAR-8 (ovary) and HCT-116 (colon). Methods: EEP was obtained by maceration with absolute ethanol, then it was concentrated in rotaevaporator up to complete evaporation of the solvent. The crude extract was fractionated with hexane, ethyl acetate, chloroform and methanol and they were subjected to phytochemical screening and total phenolic compounds. Antioxidant activity of EEP and fractions was done by means of the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. Biomarkers of red propolis were identified by LC-Orbitrap-FTMS. To assess cytotoxic activity of the extract, cells were exposed to EEP over 72 h. Cell viability was assessed by means of MTT assay. The percentage of cell growth inhibition (IC 50) was analysed by means of non-linear regression, and the absorbance values of the various investigated concentrations were subjected to one-factor analysis of variance (ANOVA) followed by Tukey's or Tamhane's tests (α = 0.05). Results: The results obtained using phytochemical screening and LC-Orbitrap-FTMS indicated the presence of phlobaphene tannins, catechins, chalcones, aurones, flavonones, flavonols, xanthones, pentacyclic triterpenoids and guttiferones in Brazilian red propolis. EEP and its hexane, chloroform and ethyl acetate fractions obtained by liquid-liquid partitioning exhibited satisfactory antioxidant percentages. EEP (IC 50 < 34.27 μg/mL) exhibited high levels of cytotoxicity on all human tumour cell lines tested when compared to negative control. Conclusions: C-Orbitrap-FTMS was useful to establish the chemical profile of the red propolis. Brazilian red propolis has antioxidant properties and decreases substantially the percentage of cell survival of human tumour cells; thus, it has potential to serve as an anticancer drug.
The ever-increasing demand for natural products and biotechnology derived from bees and ultra-mod... more The ever-increasing demand for natural products and biotechnology derived from bees and ultra-modernization of various analytical devices has facilitated the rational and planned development of biotechnology products with a focus on human health to treat chronic and neglected diseases. The aim of the present study was to prepare and characterize polymeric nanoparticles loaded with Brazilian red propolis extract and evaluate the cytotoxic activity of "multiple-constituent extract in co-delivery system" for antileishmanial therapies. The polymeric nanoparticles loaded with red propolis extract were prepared with a combination of poly-ε-caprolactone and pluronic using nanoprecipitation method and characterized by different analytical techniques, antioxidant and leishmanicidal assay. The red propolis nanoparticles in aqueous medium presented particle size (200-280 nm) in nanometric scale and zeta analysis (-20 to -26 mV) revealed stability of the nanoparticles without aggregat...
Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce... more Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (syntheticpeptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.
Background: Propolis is a natural substance produced by bees and is known to have antimicrobial a... more Background: Propolis is a natural substance produced by bees and is known to have antimicrobial activity. Our aim was to evaluate the antimicrobial effect of micellar nanocomposites loaded with an ethyl acetate extract of Brazilian red propolis as a cavity cleaning agent and its influence on the color and microtensile bond strength (μTBS) of the dentin/resin interface. Methods: An ultra-performance liquid chromatography coupled with a diode array detector (UPLC-DAD) assay was used to determine the flavonoids and isoflavones present in an ethyl acetate extract of Brazilian red propolis (EARP) and micellar nanocomposites loaded with EARP (MNRP). The antimicrobial activity of EARP and MNRP was tested against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. One of the following experimental treatments was applied to etched dentin (phosphoric acid, 15 s): 5 μL of MNRP (RP3, 0.3%; RP6, 0.6%; or RP1, 1.0% w/v), placebo, and 2% chlorhexidine digluconate. Single Bond adhesive (3 M/ESPE) was applied and a 4-mm-thick resin crown (Z350XT, 3 M/ESPE) was built up. After 24 h, the teeth were sectioned into sticks for the μTBS test and scanning electron microscopy. Spectrophotometry according to the CIE L*a*b* chromatic space was used to evaluate the color. Data were analyzed using one-way ANOVA and the Tukey test or Kruskal-Wallis test and the same test for pairwise comparisons between the means (P < 0.05).
This study evaluated the effect of dentin pretreatment with the polyphenols quercetin and resvera... more This study evaluated the effect of dentin pretreatment with the polyphenols quercetin and resveratrol on the resin-dentin microtensile bonding strength (μTBS) and collagen fibrils stability of the adhesive interface. Different concentrations (100, 250, 500, or 1,000 μg ml) of quercetin or resveratrol, or a mixture of quercetin and resveratrol (3:1, 1:1, 1:3; vol:vol), as well as distilled water or 2% chlorhexidine digluconate, were applied to etched dentin. Then, a two-step etch-and-rinse adhesive was applied followed by composite restoration. Measurements of resin-dentin μTBS were made after 1 and 120 d. The stability of collagen fibrils in the hybrid layer was evaluated using transmission electron microscopy. The Student's t-test and two-way factorial anova with Tukey's test were used to analyze the effects of dentin pretreatment and storage time on μTBS values. Comparisons between μTBS measurements made on 1 and 120 d showed that resveratrol had the best performance, with...
The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) ... more The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) simplified etch-and-rinse adhesive system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar macrophages were exposed to 200 μL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI), immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls, respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Student’s-t test (α=5%). The amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups. In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory pulpal response should be considered during the clinical application of dental adhesives.
Background: Dentine hypersensitivity (DH) occurs on exposed dentine and is dependent on the paten... more Background: Dentine hypersensitivity (DH) occurs on exposed dentine and is dependent on the patency of dentinal tubules. This study compared the effectiveness of red propolis extract (RPE), calcium sodium phosphosilicate (Novamin) and arginine-calcium carbonate (ACC) in occluding dentine tubules. Methods: Eighty dentine discs from extracted human molars were randomly divided into four groups (n = 20): Group 1 – RPE; Group 2 – Novamin; Group 3 – ACC; Group 4 – saline. The discs were etched with 37.5% phosphoric acid and treated with the test agents. Ten treated discs from each group were then exposed to 6% citric acid challenge. The extent of tubule occlusion was assessed using scanning electron microscopy (SEM). Three blinded assessors scored each SEM image on the degree of tubule occlusion. Differences in occlusion were tested using ANOVA and Tukey adjustment. Results: Discs treated with ACC demonstrated more tubule occlusion, followed by RPE and Novamin, and were greater in statistical significance when compared to discs treated with saline. Following acid challenge, RPE treated discs maintained more occlusion, followed by ACC and Novamin. Conclusions: All three agents demonstrated tubule occlusion. Although ACC showed more occlusion following treatment , RPE demonstrated a higher degree of occlusion following acid challenge.
Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface... more Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface treatments on the bond strength between pre-existing composite and repair composite resin. Materials and Methods: Forty acrylic blocks were prepared in a cuboidal mould. In each block, a well of 5 mm diameter and 5 mm depth was prepared to retain the composite resin (Filtek™ Z350, 3M/ESPE). Aging of the composite discs was achieved by storing them in water at 37°C for 1 week, and after that were divided into 5 groups (n = 8) according to surface treatment: Group I-37% phosphoric acid, Group II-10% hydrofluoric acid, Group III-30% citric acid, Group IV-7% maleic acid and Group V-Adhesive (no etchant). The etched surfaces were rinsed and dried followed by application of bonding agent (Adper™ Single Bond 2. 3M/ESPE). The repair composite was placed on aged composite, light-cured for 40 seconds and stored in water at 37°C for 1 week. Shear bond strength between the aged and the new composite resin was determined with a universal testing machine (crosshead speed of 0.5 mm/min). Statistical Analysis: The compressive shear strengths were compared for differences using ANOVA test followed by Tamhane's T2 post hoc analysis. Results: The surface treatment with 10% hydrofluoric acid showed the maximum bond strength followed by 30% citric acid, 7% maleic acid and 37% phosphoric acid in decreasing order. Conclusion: The use of 10% hydrofluoric acid can be a good alternative for surface treatment in repair of composite resin restoration as compared to commonly used 37% orthophosphoric acid.
Remoção de dentina cariada: abordagem atual REVISÃO | REVIEW RESUMO A odontologia se renova a cad... more Remoção de dentina cariada: abordagem atual REVISÃO | REVIEW RESUMO A odontologia se renova a cada dia mediante os resultados de pesquisas qualificadas. A abordagem quanto à remoção da dentina ca-riada está passando por questionamentos e inovações. O escopo desse trabalho foi realizar uma revisão literária no sentido de elucidar questões pertinentes à problemática da necessidade ou não de remover completamente a dentina cariada e da possibilidade de restaurar em sessão única, além de discutir a respeito de qual material deve ser aplicado nesse tipo de substrato. Após a análise dos artigos refe-renciados, concluiu-se que o tratamento expectante controla a progressão da cárie, há uma tendência na literatura de remover a dentina cariada parcialmente em lesões profundas e restaurar de forma definitiva. O cimento de hidróxido de cálcio é um forrador clássico nessas situações, enquanto o cimento de ionômero de vidro e os materiais resinosos representam outras possibilidades de materiais que podem estar em íntimo contato com a dentina remanescente. Termos de indexação: cárie dentária; preparo da cavidade dentária; forramento da cavidade dentária. ABSTRACT Dentistry is renewed day after day through the results of qualified researches. The approach as regards carious dentin removal is going through questioning and innovation. The scope of this study was to perform a literature review in the sense of elucidating questions pertaining to the problem of whether or not it is necessary to completely remove carious dentin, and the possibility of performing restoration in a single session, in addition to a discussion about which type of material should be applied in this type of substrate. After analyzing the refe-renced articles, it was concluded that the stepwise treatment controls caries progression; there is a trend in the literature to partially remove the carious dentin in deep lesions and perform definitive restoration; Calcium hydroxide cement is a classical liner in these situations, while glass ionomer cement and resinous materials are other possibilities of materials that can be in close contact with the remaining dentin.
The most common etiological factor for pulpal or periapical disease is microorganisms. Apical per... more The most common etiological factor for pulpal or periapical disease is microorganisms. Apical periodontitis is considered as an inflammatory reaction in the peri-apical tissues to the presence of micro-flora and their components within the root canal system. The composition of micro-flora of root canal has been studied extensively over the years and the presence of gram-positive, gram-negative bacteria and their components are considered to be the main reason for endodontic treatment failure. Bacterial components such as Lipo Poly Saccharide (LPS) and Lipoteichoic Acid (LTA) can enter the peri-apical tissue and initiate the inflammatory process by increasing the level of cytokines. Therefore, this review was done to understand the role of Lipopolysaccharide (LPS), Lipoteichoic acid (LTA) and cytokines in endodontic infection and study their relationship between each other. Data from various resources were gathered and analyzed. The activation pathway and biological effects of cytokines were also studied and it was observed that cytokines especially TNF-α (Tumour Necrosis Factor), IL-1β (Interleukin), IL-6 and IL-8 are up-regulated as a consequence of the immune response generated against the LPS and LTA. Chemokines CXCL2 (Chemokine (C-X-C motif) ligand) and CXCL10 were also shown to have increased level due to the presence of LTA. Cytokines are required to combat the foreign material during an infection, but when the level of cytokines is too high, it can cause injuries to the host itself through peri-apical bone destruction. More studies should be carried out in order to better understand the significance of each cytokine during an endodontic infection and to improve the treatment given for the patients depending on their infection status.
Pain is one of the most frequent reasons for seeking dental treatment and clinical observations c... more Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid or minimize the occurrence of post-operative sensitivity, it is imperative to make a good diagnosis and use the correct technique at all stages of the restorative procedure.
This bibliographic review provides a general view of the etiology, characteristics and treatment ... more This bibliographic review provides a general view of the etiology, characteristics and treatment of dentinal hypersensitivity, so that professionals can use this information in the therapeutic management of this clinical condition. For this purpose, the authors have analyzed whole texts of relevant articles on the subject. This study showed that the predisposing factors associated with the causes of dentinal hypersensitivity must be controlled or eliminated, by educating the patient regarding the excessive intake of acidic food, as well as providing guidance on the proper tooth brushing technique and analysis of occlusion. Effective treatment must be preceded by a proper diagnosis, established after the exclusion of any other possible causes of the pain. These cases must be managed efficiently, quickly and permanently. The availability of a wide variety of treatment could be an indicator that there is still no effective desensitizing agent to completely resolve the patient's discomfort, or that it is difficult to treat, irrespective of the available treatment options. Even with the large number of published studies, it has not been possible to reach a consensus about the product that represents the gold standard in the treatment of dentinal hypersensitivity. (J Oral Sci 51, 323-332, 2009)
Objective The aim of this study was to evaluate the incompatibility between simplified adhesive s... more Objective The aim of this study was to evaluate the incompatibility between simplified adhesive systems and dual-cure resin cement by means of marginal micro-leakage testing. Methods Standardized cavity preparations were performed in 30 bovine teeth. The adhesive systems Adper Scotchbond Multipurpose Plus (3M ESPE, St. Paul, MN, USA)-Group A, Excite (Ivoclar/Vivadent, AG, Liechtenstein)-Group B, and Adper Prompt L-Pop (3M ESPE, St. Paul, MN, USA)-Group C, were applied and the cavities were filled with dual-cure resin cement (Enforce-Denstply, Milford, DE, USA). The samples were submitted to five hundred thermal cycles, after which they were immersed in 2% buffered methylene blue. Results Group A presented the lowest mean percentage of micro-leakage (3.34%), followed by Group B (13.60%) and Group C (48.33%). Significant differences were found among the groups after the application of the Kruskal-Wallis statistical test (P=0.00). Conclusion The highest mean marginal micro-leakage values were shown with the use of the one-bottle etch-and-rinse adhesive system and the all-in-one self-etch system, which demonstrates the incompatibility between these materials.
Pain is one of the most frequent reasons for seeking dental treatment and clinical observations c... more Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid or minimize the occurrence of post-operative sensitivity, it is imperative to make a good diagnosis and use the correct technique at all stages of the restorative procedure.
The ever-increasing demand for natural products and biotechnology derived from bees and ultra-mod... more The ever-increasing demand for natural products and biotechnology derived from bees and ultra-modernization of various analytical devices has facilitated the rational and planned development of biotechnology products with a focus on human health to treat chronic and neglected diseases. The aim of the present study was to prepare and characterize polymeric nanoparticles loaded with Brazilian red propolis extract and evaluate the cytotoxic activity of " multiple-constituent extract in co-delivery system " for antileishmanial therapies. The polymeric nanoparticles loaded with red propolis extract were prepared with a combination of poly-ε-caprolactone and pluronic using nanoprecipitation method and characterized by different analytical techniques, antioxidant and leishmanicidal assay. The red propolis nanoparticles in aqueous medium presented particle size (200–280 nm) in nanometric scale and zeta analysis (−20 to −26 mV) revealed stability of the nanoparticles without aggregation phenomenon during 1 month. After freeze-drying method using cryoprotectant (sodium starch glycolate), it was possible to observe particles with smooth and spherical shape and apparent size of 200 to 400 nm. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and thermal analysis revealed the encapsulation of the flavonoids from the red propolis extract into the polymeric matrix. Ultra performance liquid chromatography coupled with diode array detector (UPLC-DAD) identified the flavonoids liquiritigenin, pinobanksin, isoliquiritigenin, formononetin and biochanin A in ethanolic extract of propolis (EEP) and nanoparticles of red propolis extract (NRPE). The efficiency of encapsulation was determinate, and median values (75.0 %) were calculated using UPLC-DAD. 2,2-Diphenyl-1-picryhydrazyl method showed antioxidant activity to EEP and red propolis nanoparticles. Compared to negative control, EEP and NRPE exhibited leishmanicidal activity with an IC50 value of ≅38.0 μg/mL and 31.3 μg/mL, 47.2 μg/mL, 154.2μg/mL and 193.2 μg/mL for NRPE A1, NRPE A2, NRPE A3 and NRPE A4, respectively. Nanoparticles loaded with red propolis extract in co-delivery system and EEP presented cytotoxic activity on Leishmania (V.) braziliensis. Red propolis extract loaded in nanoparticles has shown to be potential candidates as intermediate products for preparation of various pharmaceutical dosage forms containing red propolis extract in the therapy against negligible diseases such as leishmaniasis.
The demand for tooth-colored restorations has grown considerably during the last decade. Resin-ba... more The demand for tooth-colored restorations has grown considerably during the last decade. Resin-based Composites (RBCs), ceramics, glass ionomer cements are tooth coloured restorative materials, to name a few. Resin-based composites are the most widely used aesthetic restorative materials in today's world [1]. Now a days, at least half of posterior direct restoration placements are done using resin-based composite restorative materials [2]. The reasons for their worldwide popularity are their excellent esthetic value, needing minimal tooth preparation, providing micro-mechanical bonding with the tooth structure and good retention. However, in spite of the many advantages; one of the major shortcomings of all Resin-based Composites (RBCs) is that they undergo polymerization shrinkage upon curing. The resulting volumetric contraction produces stress between the bonded restorations and tooth walls, resulting in gap formation and microleakage. Microleakage is defined as the marginal permeability to bacterial, chemical and molecular invasion at the interface between the teeth and restorations [3], leading to discoloration, recurrent caries and pulpal pathology, affecting longevity of composite resin restorations [4-6]. Thus, resistance to microleakage of bonded restorative materials plays a crucial role in clinical success of the restoration. Over the years, various strategies have been proposed to minimize the negative effects associated with polymerization shrinkage of RBCs [7,8]. Recently, to control polymerization shrinkage, a new RBC based on silorane chemistry has been introduced. Siloranes are a new class of ring-opening monomers obtained from the reaction of oxirane and siloxane molecules [9-11]. One of the commercially silorane-based RBCs is available as Filtek P90 (3M ESPE). It is a microhybrid composite, filled with fine quartz particles, and radio-opaque yttrium fluoride. Filtek P90 is used along with P90 system adhesive, a two-step self-etching bonding system. It consists of a P90 system adhesive self-etch primer which is hydrophilic and bonds to the tooth, and a P90 system adhesive bond which is hydrophobic and adheres to the resin. Although several studies have shown conflicting results with regards to the degree of microleakage using Total-Etch (TE) and Self-Etch (SE) adhesive systems [12-17]. However, recent studies have shown that the use of a total-etch system significantly reduces microleakage than a self-etch system and three-step etch-and-rinse adhesives still remains the gold standard in terms of durability [18-20]. Thus, this study was conducted to evaluate and compare microleakage around class V cavities restored with silorane and bis-GMA based composite resins using self-etch and total-etch adhesive systems. Materials and Methods Sixty non-carious freshly extracted human molars were collected and stored in 0.2% thymol solution at room temperature until use. Routine prophylactic procedure was carried out with rubber cup and pumice slurry for all teeth. The teeth with presence of fracture, crack or pigmentation were excluded. After autoclaving teeth samples were mounted in a semicircular fashion using dental plaster in a rubber mould and set at right angle to its long axis. Abstract Objectives: To evaluate and compare microleakage around class V cavities restored with silorane and dimethacrylate-based composite resins. Methods: Standard Class V cavities were prepared on the buccal surface of 60 non-carious human molars. Teeth were randomly divided into 3 groups (n=20) depending on the restorative materials used, Silorane-based composite resin (Filtek P90-SIL), dimethacrylate-based composite resin (Solare P-SOLP) and light-cure glass ionomer cement (GC Fuji II LC-LCGIC). The restored teeth with these tooth-coloured restorative materials were thermo-cycled and then immersed in 2% Rhodamine B dye under vacuum pressure for 48 hours. All teeth were bisected longitudinally in a bucco-lingual direction and observed under stereo-microscope at 30X magnification for the evidence of dye penetration. The data were analysed using one-way analysis of variance (ANOVA) and Tukey's Post Hoc tests (α=0.05). Results: SIL composite resin showed the least microleakage in Class V cavity restorations with a statistically significant difference to SOLP and LCGIC. Sixty five percent of specimens in SIL group, 30% in SOLP group and 5% in LCGIC group showed dye penetration up to one-third of the cavity depth, while 5% in SIL group, 5% in SOLP group and 35% in LCGIC group showed dye penetration up to two-thirds of the cavity depth, and 30% in SIL group, 65% in SOLP group and 60% in LCGIC group showed dye penetration up to the axial wall. Conclusions: Silorane-based composite exhibited least microleakage in restoring class V cavities compared to dimethacrylate-based composite resin and light-cured glass ionomer cement.
: Pain is one of the most frequent reasons for seeking dental treatment and clinical observations... more : Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid...
The aim of this study was to evaluate the degree of conversion and bond strength of a commercial ... more The aim of this study was to evaluate the degree of conversion and bond strength of a commercial dental adhesive modified by the incorporation of quercetin, resveratrol (RES), and Brazilian red propolis (BRP). Methods: BRP markers were identified using ultra-performance liquid chromatography coupled with a diode array detector, and the antioxidant activity (AAO) of the three substances was analyzed. Single Bond 2 adhesive (3M ESPE) was modified by adding BRP, quercetin, and RES, separately, at 20 μg/mL, 250 μg/mL, and 500 μg/mL, respectively. The degree of conversion (DC) was measured using near-infrared spectroscopy 24 h after photopolymerization. Measurements of the resin-dentin microtensile bond strength (μTBS) were carried out after 1 day and 1 year. Student's t test and ANOVA with Tukey's test were used for data analysis (α ¼ 0.05). Results: The markers daidzein, liquiritigenin, pinobanksin, isoliquiritigenin, formononetin, pinocembrin, and biochanin A were found in the ethanolic extract of BRP. Quercetin, RES, and BRP showed high AAO. The DC of the tested adhesives remained adequate for this category of material, with a slight increase in the DC of adhesives with quercetin and BRP (P > 0.05). Comparisons between μTBS measurements made at 1 day and 1 year showed that, contrary to the control group, μTBS values for all modified adhesives were maintained after 1 year in distilled water (P > 0.05). Conclusions: These findings suggest that quercetin, RES, or BRP might be useful in adhesive dentistry to help improve hybrid layer resistance. Clinical significance: Dentin bonding agents with quercetin, RES, and BRP have potential to increase the longevity of composite restorations.
Journal of Dentistry, Oral Disorders & Therapy, 2015
The most common etiological factor for pulpal and periapical disease is microorganisms. Apical pe... more The most common etiological factor for pulpal and periapical disease is microorganisms. Apical periodontitis is considered as an inflammatory reaction in the peri-apical tissues to the presence of micro-flora and their components within the root canal system. The composition of micro-flora of root canal has been studied extensively over the years and the presence of gram-positive, gramnegative bacteria and their components are considered to be the main reason for endodontic treatment failure. Bacterial components such as Lipopolysaccharide (LPS) and Lipoteichoic Acid (LTA) can enter the peri-apical tissue and initiate the inflammatory process by increasing the level of cytokines. Therefore, this review was done to understand the role of Lipopolysaccharide (LPS), Lipoteichoic acid (LTA) and cytokines in endodontic infection and study their relationship between each other. Data from various resources were gathered and analyzed. The activation pathway and biological effects of cytokines were also studied and it was observed that cytokines especially TNF-α (Tumour Necrosis Factor), IL-1β (Interleukin), IL-6 and IL-8 are up-regulated as a consequence of the immune response generated against the LPS and LTA. Chemokines CXCL2 (Chemokine (C-X-C motif) ligand) and CXCL10 were also shown to have increased level due to the presence of LTA. Cytokines are required to combat the foreign material during an infection, but when the level of cytokines is too high, it can cause injuries to the host itself through peri-apical bone destruction. More studies should be carried out in order to better understand the significance of each cytokine during an endodontic infection and to improve the treatment given for the patients depending on their infection status.
ABSTRACT Successful root canal therapy requires a thorough knowledge of root anatomy and root can... more ABSTRACT Successful root canal therapy requires a thorough knowledge of root anatomy and root canal morphology which may be quiet variable. The significance of internal root canal morphology has been emphasized by studies demonstrating that variations in canal morphology may affect the endodontic outcome. Consequently, in treating each tooth the clinician must assume that complex anatomy occurs often enough to be considered normal. Root dilaceration is one of the variations that may complicate the endodontic therapy. It is important for a clinician to have complete knowledge of internal anatomy relationships, careful interpretation of radiographs; proper access preparation and a detailed exploration of the interior of the tooth to achieve a successful treatment outcome. This paper reports successful endodontic therapy of severe dilaceration of the root of mandibular first molar and bayonet shaped root of maxillary first premolar and highlights the clinical considerations to be followed during the endodontic procedures to get the successful outcome. Indexing terms: Dental pulp cavity. Root canal therapy. Tooth root. RESUMO Um tratamento de canal bem sucedido requer conhecimento profundo da anatomia da raiz dentaria e morfologia do canal radicular, que pode ser variavel. A importância da morfologia interna do canal radicular tem sido enfatizada por estudos que demonstram que as variacoes na morfologia do canal podem afetar o resultado do tratamento endodontico. Consequentemente, no tratamento de cada dente, o clinico deve assumir que uma anatomia complexa ocorre com frequencia suficiente para ser considerada normal. A dilaceracao da raiz dentaria e uma das variacoes que podem complicar o tratamento endodontico. E importante para o clinico ter conhecimento completo das relacoes da anatomia interna, fazer uma interpretacao cuidadosa de radiografias; preparar adequadamente o acesso e realizar uma exploracao detalhada do interior do dente para conseguir um resultado de tratamento bem sucedido. Este artigo relata casos de terapia endodontica bem sucedida de dilaceracao severa da raiz do primeiro molar inferior e de raiz em forma de baioneta de um primeiro pre-molar superior e destaca as consideracoes clinicas a serem seguidas durante os procedimentos endodonticos para se obter exito no tratamento. Termos de Indexacao: Cavidade pulpar. Tratamento do canal radicular. Raiz dentaria.
Background: The implementation of new public healthcare models that stimulate the use of natural ... more Background: The implementation of new public healthcare models that stimulate the use of natural products from traditional medicine, as a so-called integrated medicine, refers to an approach that use best of both conventional medicine and traditional medicine. Propolis is a widely used natural product by different ancient cultures and known to exhibit biological activities beneficial for health. The large number of studies conducted with propolis had shown that its chemical composition differs as a function of the climate, plant diversity and bee species and plays an important role on its therapeutic properties. The aim of this study was to analyse the phytochemical profile of the ethanolic extract of red propolis (EEP) and its fractionation, antioxidant action of EEP and its fractions hexane, cloroform and ethyl acetate and cytotoxic activity of EEP on human tumour cell lines SF-295 (glioblastoma), OVCAR-8 (ovary) and HCT-116 (colon). Methods: EEP was obtained by maceration with absolute ethanol, then it was concentrated in rotaevaporator up to complete evaporation of the solvent. The crude extract was fractionated with hexane, ethyl acetate, chloroform and methanol and they were subjected to phytochemical screening and total phenolic compounds. Antioxidant activity of EEP and fractions was done by means of the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. Biomarkers of red propolis were identified by LC-Orbitrap-FTMS. To assess cytotoxic activity of the extract, cells were exposed to EEP over 72 h. Cell viability was assessed by means of MTT assay. The percentage of cell growth inhibition (IC 50) was analysed by means of non-linear regression, and the absorbance values of the various investigated concentrations were subjected to one-factor analysis of variance (ANOVA) followed by Tukey's or Tamhane's tests (α = 0.05). Results: The results obtained using phytochemical screening and LC-Orbitrap-FTMS indicated the presence of phlobaphene tannins, catechins, chalcones, aurones, flavonones, flavonols, xanthones, pentacyclic triterpenoids and guttiferones in Brazilian red propolis. EEP and its hexane, chloroform and ethyl acetate fractions obtained by liquid-liquid partitioning exhibited satisfactory antioxidant percentages. EEP (IC 50 < 34.27 μg/mL) exhibited high levels of cytotoxicity on all human tumour cell lines tested when compared to negative control. Conclusions: C-Orbitrap-FTMS was useful to establish the chemical profile of the red propolis. Brazilian red propolis has antioxidant properties and decreases substantially the percentage of cell survival of human tumour cells; thus, it has potential to serve as an anticancer drug.
The ever-increasing demand for natural products and biotechnology derived from bees and ultra-mod... more The ever-increasing demand for natural products and biotechnology derived from bees and ultra-modernization of various analytical devices has facilitated the rational and planned development of biotechnology products with a focus on human health to treat chronic and neglected diseases. The aim of the present study was to prepare and characterize polymeric nanoparticles loaded with Brazilian red propolis extract and evaluate the cytotoxic activity of "multiple-constituent extract in co-delivery system" for antileishmanial therapies. The polymeric nanoparticles loaded with red propolis extract were prepared with a combination of poly-ε-caprolactone and pluronic using nanoprecipitation method and characterized by different analytical techniques, antioxidant and leishmanicidal assay. The red propolis nanoparticles in aqueous medium presented particle size (200-280 nm) in nanometric scale and zeta analysis (-20 to -26 mV) revealed stability of the nanoparticles without aggregat...
Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce... more Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (syntheticpeptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.
Background: Propolis is a natural substance produced by bees and is known to have antimicrobial a... more Background: Propolis is a natural substance produced by bees and is known to have antimicrobial activity. Our aim was to evaluate the antimicrobial effect of micellar nanocomposites loaded with an ethyl acetate extract of Brazilian red propolis as a cavity cleaning agent and its influence on the color and microtensile bond strength (μTBS) of the dentin/resin interface. Methods: An ultra-performance liquid chromatography coupled with a diode array detector (UPLC-DAD) assay was used to determine the flavonoids and isoflavones present in an ethyl acetate extract of Brazilian red propolis (EARP) and micellar nanocomposites loaded with EARP (MNRP). The antimicrobial activity of EARP and MNRP was tested against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. One of the following experimental treatments was applied to etched dentin (phosphoric acid, 15 s): 5 μL of MNRP (RP3, 0.3%; RP6, 0.6%; or RP1, 1.0% w/v), placebo, and 2% chlorhexidine digluconate. Single Bond adhesive (3 M/ESPE) was applied and a 4-mm-thick resin crown (Z350XT, 3 M/ESPE) was built up. After 24 h, the teeth were sectioned into sticks for the μTBS test and scanning electron microscopy. Spectrophotometry according to the CIE L*a*b* chromatic space was used to evaluate the color. Data were analyzed using one-way ANOVA and the Tukey test or Kruskal-Wallis test and the same test for pairwise comparisons between the means (P < 0.05).
This study evaluated the effect of dentin pretreatment with the polyphenols quercetin and resvera... more This study evaluated the effect of dentin pretreatment with the polyphenols quercetin and resveratrol on the resin-dentin microtensile bonding strength (μTBS) and collagen fibrils stability of the adhesive interface. Different concentrations (100, 250, 500, or 1,000 μg ml) of quercetin or resveratrol, or a mixture of quercetin and resveratrol (3:1, 1:1, 1:3; vol:vol), as well as distilled water or 2% chlorhexidine digluconate, were applied to etched dentin. Then, a two-step etch-and-rinse adhesive was applied followed by composite restoration. Measurements of resin-dentin μTBS were made after 1 and 120 d. The stability of collagen fibrils in the hybrid layer was evaluated using transmission electron microscopy. The Student's t-test and two-way factorial anova with Tukey's test were used to analyze the effects of dentin pretreatment and storage time on μTBS values. Comparisons between μTBS measurements made on 1 and 120 d showed that resveratrol had the best performance, with...
The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) ... more The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) simplified etch-and-rinse adhesive system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar macrophages were exposed to 200 μL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI), immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls, respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Student’s-t test (α=5%). The amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups. In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory pulpal response should be considered during the clinical application of dental adhesives.
Background: Dentine hypersensitivity (DH) occurs on exposed dentine and is dependent on the paten... more Background: Dentine hypersensitivity (DH) occurs on exposed dentine and is dependent on the patency of dentinal tubules. This study compared the effectiveness of red propolis extract (RPE), calcium sodium phosphosilicate (Novamin) and arginine-calcium carbonate (ACC) in occluding dentine tubules. Methods: Eighty dentine discs from extracted human molars were randomly divided into four groups (n = 20): Group 1 – RPE; Group 2 – Novamin; Group 3 – ACC; Group 4 – saline. The discs were etched with 37.5% phosphoric acid and treated with the test agents. Ten treated discs from each group were then exposed to 6% citric acid challenge. The extent of tubule occlusion was assessed using scanning electron microscopy (SEM). Three blinded assessors scored each SEM image on the degree of tubule occlusion. Differences in occlusion were tested using ANOVA and Tukey adjustment. Results: Discs treated with ACC demonstrated more tubule occlusion, followed by RPE and Novamin, and were greater in statistical significance when compared to discs treated with saline. Following acid challenge, RPE treated discs maintained more occlusion, followed by ACC and Novamin. Conclusions: All three agents demonstrated tubule occlusion. Although ACC showed more occlusion following treatment , RPE demonstrated a higher degree of occlusion following acid challenge.
Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface... more Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface treatments on the bond strength between pre-existing composite and repair composite resin. Materials and Methods: Forty acrylic blocks were prepared in a cuboidal mould. In each block, a well of 5 mm diameter and 5 mm depth was prepared to retain the composite resin (Filtek™ Z350, 3M/ESPE). Aging of the composite discs was achieved by storing them in water at 37°C for 1 week, and after that were divided into 5 groups (n = 8) according to surface treatment: Group I-37% phosphoric acid, Group II-10% hydrofluoric acid, Group III-30% citric acid, Group IV-7% maleic acid and Group V-Adhesive (no etchant). The etched surfaces were rinsed and dried followed by application of bonding agent (Adper™ Single Bond 2. 3M/ESPE). The repair composite was placed on aged composite, light-cured for 40 seconds and stored in water at 37°C for 1 week. Shear bond strength between the aged and the new composite resin was determined with a universal testing machine (crosshead speed of 0.5 mm/min). Statistical Analysis: The compressive shear strengths were compared for differences using ANOVA test followed by Tamhane's T2 post hoc analysis. Results: The surface treatment with 10% hydrofluoric acid showed the maximum bond strength followed by 30% citric acid, 7% maleic acid and 37% phosphoric acid in decreasing order. Conclusion: The use of 10% hydrofluoric acid can be a good alternative for surface treatment in repair of composite resin restoration as compared to commonly used 37% orthophosphoric acid.
Remoção de dentina cariada: abordagem atual REVISÃO | REVIEW RESUMO A odontologia se renova a cad... more Remoção de dentina cariada: abordagem atual REVISÃO | REVIEW RESUMO A odontologia se renova a cada dia mediante os resultados de pesquisas qualificadas. A abordagem quanto à remoção da dentina ca-riada está passando por questionamentos e inovações. O escopo desse trabalho foi realizar uma revisão literária no sentido de elucidar questões pertinentes à problemática da necessidade ou não de remover completamente a dentina cariada e da possibilidade de restaurar em sessão única, além de discutir a respeito de qual material deve ser aplicado nesse tipo de substrato. Após a análise dos artigos refe-renciados, concluiu-se que o tratamento expectante controla a progressão da cárie, há uma tendência na literatura de remover a dentina cariada parcialmente em lesões profundas e restaurar de forma definitiva. O cimento de hidróxido de cálcio é um forrador clássico nessas situações, enquanto o cimento de ionômero de vidro e os materiais resinosos representam outras possibilidades de materiais que podem estar em íntimo contato com a dentina remanescente. Termos de indexação: cárie dentária; preparo da cavidade dentária; forramento da cavidade dentária. ABSTRACT Dentistry is renewed day after day through the results of qualified researches. The approach as regards carious dentin removal is going through questioning and innovation. The scope of this study was to perform a literature review in the sense of elucidating questions pertaining to the problem of whether or not it is necessary to completely remove carious dentin, and the possibility of performing restoration in a single session, in addition to a discussion about which type of material should be applied in this type of substrate. After analyzing the refe-renced articles, it was concluded that the stepwise treatment controls caries progression; there is a trend in the literature to partially remove the carious dentin in deep lesions and perform definitive restoration; Calcium hydroxide cement is a classical liner in these situations, while glass ionomer cement and resinous materials are other possibilities of materials that can be in close contact with the remaining dentin.
The most common etiological factor for pulpal or periapical disease is microorganisms. Apical per... more The most common etiological factor for pulpal or periapical disease is microorganisms. Apical periodontitis is considered as an inflammatory reaction in the peri-apical tissues to the presence of micro-flora and their components within the root canal system. The composition of micro-flora of root canal has been studied extensively over the years and the presence of gram-positive, gram-negative bacteria and their components are considered to be the main reason for endodontic treatment failure. Bacterial components such as Lipo Poly Saccharide (LPS) and Lipoteichoic Acid (LTA) can enter the peri-apical tissue and initiate the inflammatory process by increasing the level of cytokines. Therefore, this review was done to understand the role of Lipopolysaccharide (LPS), Lipoteichoic acid (LTA) and cytokines in endodontic infection and study their relationship between each other. Data from various resources were gathered and analyzed. The activation pathway and biological effects of cytokines were also studied and it was observed that cytokines especially TNF-α (Tumour Necrosis Factor), IL-1β (Interleukin), IL-6 and IL-8 are up-regulated as a consequence of the immune response generated against the LPS and LTA. Chemokines CXCL2 (Chemokine (C-X-C motif) ligand) and CXCL10 were also shown to have increased level due to the presence of LTA. Cytokines are required to combat the foreign material during an infection, but when the level of cytokines is too high, it can cause injuries to the host itself through peri-apical bone destruction. More studies should be carried out in order to better understand the significance of each cytokine during an endodontic infection and to improve the treatment given for the patients depending on their infection status.
Pain is one of the most frequent reasons for seeking dental treatment and clinical observations c... more Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid or minimize the occurrence of post-operative sensitivity, it is imperative to make a good diagnosis and use the correct technique at all stages of the restorative procedure.
This bibliographic review provides a general view of the etiology, characteristics and treatment ... more This bibliographic review provides a general view of the etiology, characteristics and treatment of dentinal hypersensitivity, so that professionals can use this information in the therapeutic management of this clinical condition. For this purpose, the authors have analyzed whole texts of relevant articles on the subject. This study showed that the predisposing factors associated with the causes of dentinal hypersensitivity must be controlled or eliminated, by educating the patient regarding the excessive intake of acidic food, as well as providing guidance on the proper tooth brushing technique and analysis of occlusion. Effective treatment must be preceded by a proper diagnosis, established after the exclusion of any other possible causes of the pain. These cases must be managed efficiently, quickly and permanently. The availability of a wide variety of treatment could be an indicator that there is still no effective desensitizing agent to completely resolve the patient's discomfort, or that it is difficult to treat, irrespective of the available treatment options. Even with the large number of published studies, it has not been possible to reach a consensus about the product that represents the gold standard in the treatment of dentinal hypersensitivity. (J Oral Sci 51, 323-332, 2009)
Objective The aim of this study was to evaluate the incompatibility between simplified adhesive s... more Objective The aim of this study was to evaluate the incompatibility between simplified adhesive systems and dual-cure resin cement by means of marginal micro-leakage testing. Methods Standardized cavity preparations were performed in 30 bovine teeth. The adhesive systems Adper Scotchbond Multipurpose Plus (3M ESPE, St. Paul, MN, USA)-Group A, Excite (Ivoclar/Vivadent, AG, Liechtenstein)-Group B, and Adper Prompt L-Pop (3M ESPE, St. Paul, MN, USA)-Group C, were applied and the cavities were filled with dual-cure resin cement (Enforce-Denstply, Milford, DE, USA). The samples were submitted to five hundred thermal cycles, after which they were immersed in 2% buffered methylene blue. Results Group A presented the lowest mean percentage of micro-leakage (3.34%), followed by Group B (13.60%) and Group C (48.33%). Significant differences were found among the groups after the application of the Kruskal-Wallis statistical test (P=0.00). Conclusion The highest mean marginal micro-leakage values were shown with the use of the one-bottle etch-and-rinse adhesive system and the all-in-one self-etch system, which demonstrates the incompatibility between these materials.
Pain is one of the most frequent reasons for seeking dental treatment and clinical observations c... more Pain is one of the most frequent reasons for seeking dental treatment and clinical observations confirm that patients complain of dentinal sensitivity under different conditions and degrees of intensity. This is a very frequent problem after dental restorations with resin composite, even when there is no visible failure in the restoration. The aim of this bibliographic review was to identify the causes of post-operative sensitivity in resin composite restorations and how it can be avoided so that professionals can use this information to reduce the occurrence of this inconvenience in their daily practice. Complete texts of relevant articles on the subject were analysed. There are various causes of post-operative sensitivity in direct resin composite restorations related to failures in diagnosis and indications for treatment and/or cavity preparation, the stages of hybridization of hard dental tissues, insertion of the material, and finishing and polishing the restoration. To avoid or minimize the occurrence of post-operative sensitivity, it is imperative to make a good diagnosis and use the correct technique at all stages of the restorative procedure.
The ever-increasing demand for natural products and biotechnology derived from bees and ultra-mod... more The ever-increasing demand for natural products and biotechnology derived from bees and ultra-modernization of various analytical devices has facilitated the rational and planned development of biotechnology products with a focus on human health to treat chronic and neglected diseases. The aim of the present study was to prepare and characterize polymeric nanoparticles loaded with Brazilian red propolis extract and evaluate the cytotoxic activity of " multiple-constituent extract in co-delivery system " for antileishmanial therapies. The polymeric nanoparticles loaded with red propolis extract were prepared with a combination of poly-ε-caprolactone and pluronic using nanoprecipitation method and characterized by different analytical techniques, antioxidant and leishmanicidal assay. The red propolis nanoparticles in aqueous medium presented particle size (200–280 nm) in nanometric scale and zeta analysis (−20 to −26 mV) revealed stability of the nanoparticles without aggregation phenomenon during 1 month. After freeze-drying method using cryoprotectant (sodium starch glycolate), it was possible to observe particles with smooth and spherical shape and apparent size of 200 to 400 nm. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and thermal analysis revealed the encapsulation of the flavonoids from the red propolis extract into the polymeric matrix. Ultra performance liquid chromatography coupled with diode array detector (UPLC-DAD) identified the flavonoids liquiritigenin, pinobanksin, isoliquiritigenin, formononetin and biochanin A in ethanolic extract of propolis (EEP) and nanoparticles of red propolis extract (NRPE). The efficiency of encapsulation was determinate, and median values (75.0 %) were calculated using UPLC-DAD. 2,2-Diphenyl-1-picryhydrazyl method showed antioxidant activity to EEP and red propolis nanoparticles. Compared to negative control, EEP and NRPE exhibited leishmanicidal activity with an IC50 value of ≅38.0 μg/mL and 31.3 μg/mL, 47.2 μg/mL, 154.2μg/mL and 193.2 μg/mL for NRPE A1, NRPE A2, NRPE A3 and NRPE A4, respectively. Nanoparticles loaded with red propolis extract in co-delivery system and EEP presented cytotoxic activity on Leishmania (V.) braziliensis. Red propolis extract loaded in nanoparticles has shown to be potential candidates as intermediate products for preparation of various pharmaceutical dosage forms containing red propolis extract in the therapy against negligible diseases such as leishmaniasis.
The demand for tooth-colored restorations has grown considerably during the last decade. Resin-ba... more The demand for tooth-colored restorations has grown considerably during the last decade. Resin-based Composites (RBCs), ceramics, glass ionomer cements are tooth coloured restorative materials, to name a few. Resin-based composites are the most widely used aesthetic restorative materials in today's world [1]. Now a days, at least half of posterior direct restoration placements are done using resin-based composite restorative materials [2]. The reasons for their worldwide popularity are their excellent esthetic value, needing minimal tooth preparation, providing micro-mechanical bonding with the tooth structure and good retention. However, in spite of the many advantages; one of the major shortcomings of all Resin-based Composites (RBCs) is that they undergo polymerization shrinkage upon curing. The resulting volumetric contraction produces stress between the bonded restorations and tooth walls, resulting in gap formation and microleakage. Microleakage is defined as the marginal permeability to bacterial, chemical and molecular invasion at the interface between the teeth and restorations [3], leading to discoloration, recurrent caries and pulpal pathology, affecting longevity of composite resin restorations [4-6]. Thus, resistance to microleakage of bonded restorative materials plays a crucial role in clinical success of the restoration. Over the years, various strategies have been proposed to minimize the negative effects associated with polymerization shrinkage of RBCs [7,8]. Recently, to control polymerization shrinkage, a new RBC based on silorane chemistry has been introduced. Siloranes are a new class of ring-opening monomers obtained from the reaction of oxirane and siloxane molecules [9-11]. One of the commercially silorane-based RBCs is available as Filtek P90 (3M ESPE). It is a microhybrid composite, filled with fine quartz particles, and radio-opaque yttrium fluoride. Filtek P90 is used along with P90 system adhesive, a two-step self-etching bonding system. It consists of a P90 system adhesive self-etch primer which is hydrophilic and bonds to the tooth, and a P90 system adhesive bond which is hydrophobic and adheres to the resin. Although several studies have shown conflicting results with regards to the degree of microleakage using Total-Etch (TE) and Self-Etch (SE) adhesive systems [12-17]. However, recent studies have shown that the use of a total-etch system significantly reduces microleakage than a self-etch system and three-step etch-and-rinse adhesives still remains the gold standard in terms of durability [18-20]. Thus, this study was conducted to evaluate and compare microleakage around class V cavities restored with silorane and bis-GMA based composite resins using self-etch and total-etch adhesive systems. Materials and Methods Sixty non-carious freshly extracted human molars were collected and stored in 0.2% thymol solution at room temperature until use. Routine prophylactic procedure was carried out with rubber cup and pumice slurry for all teeth. The teeth with presence of fracture, crack or pigmentation were excluded. After autoclaving teeth samples were mounted in a semicircular fashion using dental plaster in a rubber mould and set at right angle to its long axis. Abstract Objectives: To evaluate and compare microleakage around class V cavities restored with silorane and dimethacrylate-based composite resins. Methods: Standard Class V cavities were prepared on the buccal surface of 60 non-carious human molars. Teeth were randomly divided into 3 groups (n=20) depending on the restorative materials used, Silorane-based composite resin (Filtek P90-SIL), dimethacrylate-based composite resin (Solare P-SOLP) and light-cure glass ionomer cement (GC Fuji II LC-LCGIC). The restored teeth with these tooth-coloured restorative materials were thermo-cycled and then immersed in 2% Rhodamine B dye under vacuum pressure for 48 hours. All teeth were bisected longitudinally in a bucco-lingual direction and observed under stereo-microscope at 30X magnification for the evidence of dye penetration. The data were analysed using one-way analysis of variance (ANOVA) and Tukey's Post Hoc tests (α=0.05). Results: SIL composite resin showed the least microleakage in Class V cavity restorations with a statistically significant difference to SOLP and LCGIC. Sixty five percent of specimens in SIL group, 30% in SOLP group and 5% in LCGIC group showed dye penetration up to one-third of the cavity depth, while 5% in SIL group, 5% in SOLP group and 35% in LCGIC group showed dye penetration up to two-thirds of the cavity depth, and 30% in SIL group, 65% in SOLP group and 60% in LCGIC group showed dye penetration up to the axial wall. Conclusions: Silorane-based composite exhibited least microleakage in restoring class V cavities compared to dimethacrylate-based composite resin and light-cured glass ionomer cement.
Uploads
Papers by Isabel Porto
system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium
for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar
macrophages were exposed to 200 μL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI),
immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls,
respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Student’s-t test (α=5%). The
amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing
that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused
intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups.
In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory
pulpal response should be considered during the clinical application of dental adhesives.
system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium
for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar
macrophages were exposed to 200 μL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI),
immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls,
respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Student’s-t test (α=5%). The
amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing
that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused
intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups.
In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory
pulpal response should be considered during the clinical application of dental adhesives.