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1.
Children (Basel) ; 11(2)2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38397261

RESUMEN

Diet plays an important role in the etiopathology of dental caries. Milk and dairy products (DPs), especially in children and adolescents, are important sources of protein, calcium and phosphorus and could have an effect on dental and oral health. The aim of this scoping review was to analyze the scientific literature on the non-cariogenic effect of milk and DPs, with a focus on their potential to prevent dental caries in children and adolescents. PubMed, EMBASE, and Web of Science were searched for publications relevant to our topic from January 2013 to 30 September 2023. Thirty-eight studies were included in the qualitative analysis. The included studies highlight the properties of milk and DPs that contribute to enamel remineralization, exhibit antibacterial action, inhibit the growth of cariogenic bacteria, and promote a balanced oral microbiome. With regard to the addition of probiotics (PBs) and fluoride (F) to DPs, the mixed results of the studies analyzed did not allow a clear statement to be made about their non-cariogenic effects. However, several studies show that the addition of PBs can reduce cariogenic bacteria, create a protective barrier against pathogens and support the host's natural defense mechanisms. Further long-term and high-quality studies are needed to understand the impact of milk and its constituents on oral health in order to promote effective caries prevention strategies in children and adolescents.

2.
J Transl Med ; 22(1): 120, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297308

RESUMEN

BACKGROUND: One of the main factors for the osseointegration of dental implants is the development of an adequate soft tissue barrier, mainly composed by collagen, which protects the implant from bacterial development. The structural features of the peri-implant collagen are influenced by the implant components and, in particular, by the type of the surface. In the clinical practice, healing abutments are characterized by smooth surfaces, named machined. Recently, a new laser technique, Synthegra, has been developed to obtain a topography-controlled surface with micrometric regular pores that seems reducing the risk of peri-implantitis. Based on this background, this study aims investigating the structural organization and spatial distribution of collagen surrounding healing abutments characterized by laser-treated and machined surfaces. METHODS: Gingiva portions surrounding custom-made healing abutments (HA), characterized by alternated laser-treated and machined surfaces, were collected and analyzed by combining Fourier Transform InfraRed Imaging (FTIRI) spectroscopy, a non-invasive and high-resolution bidimensional analytical technique, with histological and multivariate analyses. RESULTS: Masson's trichrome staining, specific for collagen, highlighted a massive presence of collagen in all the analyzed samples, evidencing a surface-related spatial distribution. The nature of collagen, investigated by the FTIRI spectroscopy, appeared more abundant close to the laser-treated surface, with a perpendicular disposition of the bundles respect to the HA; conversely, a parallel distribution was observed around the machined surface. A different secondary structure was also found, with a higher amount of triple helices and a lower quantity of random coils in collagen close to the laser treated surfaces. CONCLUSIONS: FTIRI spectroscopy demonstrates that the use of a laser treated transmucosal surface can improve the morphological organization of the peri-implant collagen, which presents a distribution more similar to that of natural teeth. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT05754970). Registered 06/03/2023, retrospectively registered, https://clinicaltrials.gov/show/NCT05754970 .


Asunto(s)
Implantes Dentales , Colágeno , Encía/patología , Rayos Láser , Oseointegración , Propiedades de Superficie , Humanos
3.
Clin Oral Investig ; 27(12): 7451-7462, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37857734

RESUMEN

OBJECTIVES: This in vitro study aimed assessing the remineralization potential of three commercial fluoride-based toothpastes in permanent teeth with natural white spot lesions (WSLs). A multidisciplinary approach based on Raman microspectroscopy (RMS), Scanning electron microscopy (SEM), Energy-dispersive x-ray spectroscopy (EDS), and Vickers microhardness (VMH) was exploited. METHODS: N = 12 human molars with natural WSLs in the proximal-vestibular zone were selected and divided into 4 groups (n = 3) according to the different treatments: HAF (hydroxyapatite with fluoride ions); SMF (sodium monofluorophosphate with arginine); SF (sodium fluoride with enzymes), and CTRL (untreated group). All toothpastes tested contained 1450 ppm of fluoride. Teeth samples were submitted to the following protocol: a 7-day pH cycling treatment, with two daily exposures (2 min each time) to the commercial toothpastes described above. The surface micromorphology (SEM), the chemical/elemental composition (RMS and EDS), and the Vickers microhardness (VMH) were evaluated. Statistical analysis was performed. RESULTS: A remarkable remineralization of WSLs in SEM images was observed in all treated groups compared to CTRL. In particular, HAF and SF displayed higher values of VMH, phosphates amount (I960), crystallinity (FWHM960), and lower ones of C/P (I1070/I960) with respect to CTRL. Intermediate values were found in SMF, higher than CTRL but lower with respect to HAF and SF. As regards the Ca/P ratio, statistically significant differences (p < 0.05) were found between SF and the other groups. CONCLUSIONS: All the tested dentifrices have shown to remineralize the WSLs. SF and HAF have comparable capability in hardness recovery and crystallinity; however, SF shows the best remineralizing potential according to both micromorphological and chemical analyses. Clinical relevance The daily use of toothpastes containing hydroxyapatite partially replaced with fluoride, sodium monofluorophosphate with arginine and sodium fluoride toothpaste associated with enzymes represents a preventive, therapeutic, effective, and non-invasive tool for remineralize WSLs.


Asunto(s)
Caries Dental , Fluoruros , Humanos , Fluoruros/farmacología , Pastas de Dientes/farmacología , Pastas de Dientes/uso terapéutico , Fluoruro de Sodio/farmacología , Fluoruro de Sodio/uso terapéutico , Esmalte Dental , Caries Dental/tratamiento farmacológico , Caries Dental/prevención & control , Arginina/farmacología , Hidroxiapatitas/farmacología , Remineralización Dental/métodos , Cariostáticos/uso terapéutico
4.
Analyst ; 148(18): 4365-4372, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37548234

RESUMEN

Raman MicroSpectroscopy (RMS) is a powerful label-free tool to probe the effects of drugs at a cellular/subcellular level. It is important, however, to be able to extract relevant biochemical and kinetic spectroscopic signatures of the specific cellular responses. In the present study, a combination of Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) and Principal Component Analysis (PCA) is used to analyse the RMS data for the example of exposure of primary Oral Squamous Carcinoma Cells (OSCC) to the chemotherapeutic agent cisplatin. Dosing regimens were established by cytotoxicity assays, and the effects of the drug on cellular spectral profiles were monitored from 16 to 72 hours post-exposure using an apoptosis assay, to establish the relative populations of viable (V), early (EA) and late apoptotic/dead (LA/D) cells after the drug treatment. Based on a kinetic model of the progression from V > EA > D, MCR-ALS regression analysis of the RMS responses was able to extract spectral profiles associated with each stage of the cellular responses, enabling a quantitative comparison of the response rates for the respective drug treatments. Moreover, PCA was used to compare the spectral profiles of the viable cells exposed to the drug. Spectral differences were highlighted in the early stages (16 hours exposure), indicative of the initial cellular response to the drug treatment, and also in the late stages (48-72 hours exposure), representing the cell death pathway. The study demonstrates that RMS coupled with multivariate analysis can be used to quantitatively monitor the progression of cellular responses to different drugs, towards future applications for label-free, in vitro, pre-clinical screening.


Asunto(s)
Carcinoma de Células Escamosas , Cisplatino , Humanos , Cisplatino/farmacología , Análisis de los Mínimos Cuadrados , Espectrometría Raman/métodos , Carcinoma de Células Escamosas/tratamiento farmacológico , Análisis Multivariante
5.
Bioengineering (Basel) ; 10(4)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37106649

RESUMEN

This study aimed to evaluate the loss of mineral content in the enamel surface in early artificial lesions and to assess the remineralizing potential of different agents by means of SEM coupled with energy-dispersive X-ray analysis (EDX). The analysis was performed on the enamel of 36 molars divided into six equal groups, in which the experimental ones (3-6) were treated using remineralizing agents for a 28-day pH cycling protocol as follows: Group 1, sound enamel; Group 2, artificially demineralized enamel; Group 3, CPP-ACP treatment; Group 4, Zn-hydroxyapatite treatment; Group 5, NaF 5% treatment; and Group 6, F-ACP treatment. Surface morphologies and alterations in Ca/P ratio were evaluated using SEM-EDX and data underwent statistical analysis (p < 0.05). Compared with the sound enamel of Group 1, the SEM images of Group 2 clearly showed loss of integrity, minerals, and interprismatic substances. Groups 3-6 showed a structural reorganization of enamel prisms, interestingly comprising almost the entire enamel surface. Group 2 revealed highly significant differences of Ca/P ratios compared with other groups, while Groups 3-6 showed no differences with Group 1. In conclusion, all tested materials demonstrated a biomimetic ability in remineralizing lesions after 28 days of treatment.

6.
Sci Total Environ ; 866: 161356, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36603638

RESUMEN

Clear orthodontic aligners have recently seen increasing popularity. The thermoplastic materials present several advantages, even if it is known that all plastic products can be subjected to environmental and mechanical degradation, leading to the release of microplastics (MPs). Their ingestion could cause oxidative stress and inflammatory lesions. This study aims to evaluate the potential detachment of MPs by clear aligners due to mechanical friction simulated with a 7-day protocol in artificial saliva. The study was performed on orthodontic clear aligners from different manufacturers: Alleo (AL); FlexiLigner (FL); F22 Aligner (F22); Invisalign® (INV); Lineo (LIN); Arc Angel (ARC), and Ortobel Aligner (OR). For each group, two aligners were immersed in artificial saliva for 7 days and stirred for 5 h/day, simulating the physiological teeth mechanical friction. After 7 days, the artificial saliva was filtered; then, filters were analyzed by Raman Microspectroscopy (RMS) and Scanning Electron Microscopy (SEM), respectively to chemically identify the polymeric matrix and to measure the number and size of the detected MPs. RMS spectra revealed that AL, FL, LIN, ARC, and OR aligners were composed by polyethylene terephthalate, while F22 and INV ones by polyurethane. SEM analysis showed that the highest number of MPs was found in ARC and the lowest in INV (p < 0.05). As regards MPs' size, no statistically significant difference was found among groups, with most MPs ranging from 5 to 20 µm. Noteworthy, a highly significant correlation (p < 0.0001) was highlighted between the distribution of MPs size and the different typologies of aligners. This in vitro study highlighted for the first time the detachment of MPs from clear aligners due to mechanical friction. This evidence may represent a great concern in the clinical practice since it could impact human general health.


Asunto(s)
Aparatos Ortodóncicos Removibles , Plásticos , Humanos , Saliva Artificial , Microplásticos , Análisis Espectral
7.
Materials (Basel) ; 15(13)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35806523

RESUMEN

Dental remineralization represents the process of depositing calcium and phosphate ions into crystal voids in demineralized enamel, producing net mineral gain and preventing early enamel lesions progression. The aim of the present study was to qualitatively and quantitatively compare the remineralizing effectiveness of four commercially available agents on enamel artificial lesions using Scanning Electron Microscopy (SEM) combined with Energy Dispersive Spectroscopy (EDS) techniques. Thirty-six extracted third molars were collected and randomly assigned to six groups (n = 6), five of which were suspended in demineralizing solution for 72 h to create enamel artificial lesions, and one serving as control: G1, treated with a mousse of casein phosphopeptide and amorphous calcium−phosphate (CPP-ACP); G2, treated with a gel containing nano-hydroxyapatite; G3, treated with a 5% SF varnish; G4, treated with a toothpaste containing ACP functionalized with fluoride and carbonate-coated with citrate; G5, not-treated artificial enamel lesions; G6, not demineralized and not treated sound enamel. G1−G4 were subjected to pH cycling over a period of seven days. Analyses of the specimens' enamel surfaces morphology were performed by SEM and EDS. Data were statistically analyzed for multiple group comparison by one-way ANOVA/Tukey's test (p < 0.05). The results show that the Ca/P ratio of the G5 (2.00 ± 0.07) was statistically different (p < 0.05) from G1 (1.73 ± 0.05), G2 (1.76 ± 0.01), G3 (1.88 ± 0.06) and G6 (1.74 ± 0.04), while there were no differences (p > 0.05) between G1, G2 and G6 and between G4 (2.01 ± 0.06) and G5. We concluded that G1 and G2 showed better surface remineralization than G3 and G4, after 7 days of treatment.

8.
Artículo en Inglés | MEDLINE | ID: mdl-34886241

RESUMEN

BACKGROUND: COVID-19 disease first appeared in 2019 and quickly spread worldwide, causing a global pandemic. The oral cavity represents a target of SARS-CoV-2, and oral lesions are observed in both non-hospitalized and hospitalized patients. This systematic review aims to investigate the frequency of oral manifestations in COVID-19 hospitalized patients. METHODS: An electronic search was conducted in PubMed, Scopus, and Web of Science databases, including articles published up to September 2021. The review protocol was based on PRISMA-P. The risk of bias of the studies was assessed using the Joana Briggs Institute. The certainty of evidence was assessed using the GRADE instrument. RESULTS: Fifty-nine articles were included: 19 case reports, 17 case series, 2 case-control studies, 13 cross-sectional studies, 4 observational studies, and 4 retrospective studies. Oral ulcers, cheilitis, and tongue lesions were more common in patients before hospitalization, while perioral pressure ulcers, macroglossia, blisters, and oral candidiasis were more recurrent in patients during hospitalization. The first could be related directly to COVID-19, while the latter could be caused by medical devices, treatments, prone position, and immunological impairment. CONCLUSIONS: An accurate oral examination during the hospital admission of all confirmed COVID-19 cases is encouraged to recognize oral early manifestations and to apply appropriate treatments.


Asunto(s)
COVID-19 , Estudios Transversales , Humanos , Metaanálisis como Asunto , Estudios Retrospectivos , SARS-CoV-2
9.
Cells ; 10(8)2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34440896

RESUMEN

In the present study, the cytotoxic effects of 5-azacytidine on primary Oral Squamous Cell Carcinoma cells (OSCCs) from human biopsies, and on Cancer Stem Cells (CSCs) from the same samples, were investigated by an in vitro Fourier Transform InfraRed Microscospectroscopy (FTIRM) approach coupled with multivariate analysis. OSCC is an aggressive tumoral lesion of the epithelium, accounting for ~90% of all oral cancers. It is usually diagnosed in advanced stages, and this causes a poor prognosis with low success rates of surgical, as well as radiation and chemotherapy treatments. OSCC is frequently characterised by recurrence after chemotherapy and by the development of a refractoriness to some employed drugs, which is probably ascribable to the presence of CSCs niches, responsible for cancer growth, chemoresistance and metastasis. The spectral information from FTIRM was correlated with the outcomes of cytotoxicity tests and image-based cytometry, and specific spectral signatures attributable to 5-azacytidine treatment were identified, allowing us to hypothesise the demethylation of DNA and, hence, an increase in the transcriptional activity, together with a conformational transition of DNA, and a triggering of cell death by an apoptosis mechanism. Moreover, a different mechanism of action between OSSC and CSC cells was highlighted, probably due to possible differences between OSCCs and CSCs response.


Asunto(s)
Azacitidina/farmacología , Carcinoma de Células Escamosas/metabolismo , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Espectroscopía Infrarroja por Transformada de Fourier , Células Tumorales Cultivadas
10.
Microsc Res Tech ; 84(12): 2922-2929, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34105839

RESUMEN

This study aims to evaluate the effects of different finishing and polishing (F/P) systems on gloss and surface morphology of a new nanocomposite. Thirty discs of Filtek Universal Restorative material (3 M, ESPE) were prepared and divided into six groups (n = 5). Group A and B followed F/P protocols for anterior restorations, whereas Group C and D for posterior ones. Group E represented the control (covered by Mylar strip) and Group F represented the nanocomposite placement by means of clinical hand instruments; Groups E and F did not undergo F/P procedures. Among the polished groups, Group B showed the highest values (68.54 ± 7.54 GU), followed by Group A and D (46.87 ± 5.52 GU; 53.76 ± 2.65 GU). Finally, Group C (37.38 ± 4.93 GU) displayed the lowest results. Overall, Group E showed the highest gloss values (93.45 ± 8.27 GU), while Group F presented the lowest ones (1.74 ± 0.64 GU). Surface analysis revealed that Group A, C, and D displayed a smooth surface. Group B showed the lowest irregularities. Group E exhibited the most uniform superficial morphology. On the other hand, Group F displayed the most irregular one. In conclusion, using the tested material, only two protocols achieved appropriate gloss values. Then, clinicians might use the protocols of Group B and Group D, for anterior and posterior restorations, respectively.


Asunto(s)
Resinas Compuestas , Nanocompuestos , Pulido Dental , Ensayo de Materiales , Propiedades de Superficie
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 260: 119966, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34052763

RESUMEN

Teeth are characterized by a specific chemical composition and microstructure, which are related to their nature, permanent and deciduous, and to the sides, lingual and vestibular. Deeper knowledge in this topic could be useful in clinical practice to develop new strategies in restorative dentistry and in the choice of materials with the best performances. In this study, Raman MicroSpectroscopy (RMS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDS), and Vickers MicroHardness (VMH) were exploited to: (1) identify the microstructure and the chemical/elemental composition of permanent and deciduous human teeth, also characterizing their lingual and vestibular sides, and (2) validate a new multidisciplinary analytical approach, for obtaining multiple information on calcified tissues. All applied techniques evidenced differences between permanent and deciduous teeth both in the lingual and vestibular sides. In particular, scanning electron micrographs identified areas with an irregular appearance in the vestibular and lingual sides, which presented also different VMH values. Moreover, RMS and EDS displayed a different chemical/elemental composition in outer and inner enamel and dentin, in terms of Mineral/Matrix, Crystallinity, Carbonates/phosphates, and concentrations by weight (%) of calcium, phosphorous, carbon, magnesium, and sodium. A good linear correlation was found between RMS spectral profiles and EDS and VMH measurements, suggesting that RMS may be considered a useful and non-destructive diagnostic tool for obtaining multiple information on calcified tissues.


Asunto(s)
Fósforo , Diente Primario , Humanos , Microscopía Electrónica de Rastreo , Minerales , Espectrometría por Rayos X
12.
Materials (Basel) ; 14(4)2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33572096

RESUMEN

Clear and removable tooth aligners for orthodontics treatments have become an increasingly popular alternative to fixed appliances. Even if protocols suggest removing aligners before eating or drinking, most patients retain them when they drink beverages. Alterations in the material during the daily use could determine a reduction in the application forces, affecting the desired orthodontic movement; the knowledge of how this material reacts when subjected to different aging processes is mandatory to establish the predictability of the orthodontic treatment. According to this, the aim of the present study was to assess a new objective approach, coupling spectroscopic and chemometric tools, to evaluate the changes occurring in Invisalign® aligners, the most widely used brand, exposed in vitro to coffee, tea, Coca Cola® and UV radiation for 24 and 48 h. In particular, ATR-FTIR spectroscopy was utilized to characterize, at the molecular level, the chemical and color modifications in the surfaces of the appliances; the obtained data were submitted to PCA and one-way ANOVA and Tukey's multiple comparison test. Moreover, a colorimetry analysis was carried out to evaluate any changes in color and transparency. Coffee and tea samples displayed the major color changes between the tested groups. The differences highlighted in the spectral features of coffee, tea and UV-treated samples were mainly ascribable to color and transparency changes, because the chemical properties remained unaltered.

13.
PeerJ ; 9: e10606, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33575125

RESUMEN

BACKGROUND: Tooth whitening is one of the most requested dental treatments, but it still presents some side effects. Indeed, the bleaching agent can generate patients' discomfort and dental hard tissue damages, not achieving an efficient and long-lasting treatment with optimum whitening effect. To overcome these limitations, the bleaching agents containing nano-hydroxyapatite can represent a reliable solution to avoid these detrimental effects. METHODS: In this study, human third molars were treated with commercial bleaching agents, containing nano-hydroxyapatite (nHA) and 6% (at-home treatment), 12% and 18% (in-office treatments) of hydrogen peroxide (HP), named respectively G1, G2 and G3. The results were evaluated descriptively and analytically using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDS), comparing the treated groups with a commercial gel containing 10% carbamide peroxide (CONV) and with a non-treated control group (CTRL). RESULTS: ATR-FTIR analysis revealed a similar composition in carbonates and phosphates for CTRL, G1 and G2 groups, which showed no significant differences in their spectral profiles; an increased amount of organic matter was found in G3, while CONV displayed an intermediate behavior. SEM analysis did not highlight significant changes in the enamel microstructure of G1 and CONV when compared to CTRL; the pattern observed in G2 presented a slight increase of enamel irregularities, while G3 displayed a partial removal of the aprismatic layer and microporosities. No evident effects due to nHA were observed in the structure of the hydroxyapatite component of G1, G2 and CONV, if compared to CTRL, while G3 showed a slight loss of crystallinity. In all groups, EDS identified slight changes in the concentration of chemical elements O and Ca, while the Ca/P ratio was similar when compared to CTRL. CONCLUSION: The obtained results suggest that the application of the tested commercial bleaching agents, with a concentration of HP up to 12%, does not alter the morphological and chemical composition of the enamel surface and maintains its crystallinity.

14.
Materials (Basel) ; 14(2)2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33466862

RESUMEN

One of the current major challenges in implant therapy is to minimize marginal bone loss around implants, since it can trigger bacterial colonization of the implant's neck, leading to its failure. The present study aimed (1) to scientifically validate a new mathematical rule based on soft tissues thickness, for choosing the correct implant position with respect to the bone level, in order to provide a better tissue adaptation to the abutment/implant surface to avoid bacterial invasion, and (2) to apply this mathematical rule to the Biological Oriented Immediate Loading (B.O.I.L.) surgical protocol, avoiding peri-implant bone resorption. N. 127 implants were inserted following B.O.I.L. protocol: implants were placed according to the mathematical rule Y = X - 3, which correlates the position of the implant from the bone crest level (Y) with the thickness of the soft tissues (X). All the implants were inserted in fresh extraction sockets, and immediately loaded with temporary abutments and prostheses. Bone levels were evaluated through radiographic examination just after surgical procedure (T0), and after 10 days (10D), 6 months (6M), 1 year (1Y), and 5 years (5Y). After 5 years, the implant survival rate was 100%, with a medium marginal bone loss around implants of 0.0704 mm (SD = 0.169 mm). One-way ANOVA, followed by Tukey's multiple comparison test was performed for statistical evaluations (p < 0.05). This protocol provided a safe and successful procedure, with a good soft tissue seal against bacterial challenge. The application of the mathematical rule allows the implant placement in a correct vertical position from the bone crest, avoiding bone resorption and bacterial infiltrations. Moreover, the use of Multi Unit Abutment (MUA) determined a stable biological seal, favouring the implant healing and preserving the adhesion of hemidesmosomes to the titanium of MUA.

15.
Analyst ; 145(24): 8038-8049, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33063801

RESUMEN

Oral Squamous Cells Carcinoma (OSCC) is characterised by the risk of recurrence and the onset of a refractoriness response to chemotherapy drugs. These phenomena have been recently related to a subpopulation of Cancer Stem Cells (CSCs), which have either an innate or acquired drug resistance, triggered by chemotherapy treatments. In this light, to precisely target chemotherapy regimens, it is essential to improve knowledge on CSCs, with a particular focus on their molecular features. In this work, a subpopulation of CSCs, isolated by tumour sphere formation from primary OSCC cells, were treated with cisplatin for 16, 24 and 48 hours and analysed by infrared absorption and Raman microspectroscopies. CSC spectral data were compared with those obtained in previous work, for primary OSCC cells treated under the same conditions. Routine viability/apoptosis cell-based assays evidenced in CSCs and primary OSCCs, a similar degree of sensitivity to the drug at 24 hours, while a reversion of the conventional monotonic time response exhibited by OSCCs was shown by CSCs at 48 hours. This peculiar time response was also supported by the analysis of IR and Raman data, which pinpointed alterations in the lipid composition and DNA conformation in CSCs. The results obtained suggest that CSCs, although sharing with OSCC cells a similar sensitivity to cisplatin, display the onset of a mechanism of chemoresistance and enrichment of resistant CSCs as a result of drug treatment, shedding new light on the severe issue of refractoriness of some patients to chemotherapy conventionally used for OSCC.


Asunto(s)
Cisplatino , Resistencia a Antineoplásicos , Línea Celular Tumoral , Cisplatino/farmacología , Células Epiteliales , Análisis de Fourier , Humanos , Recurrencia Local de Neoplasia , Células Madre Neoplásicas
16.
Odontology ; 109(2): 433-439, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33128650

RESUMEN

This study aims to compare the degree of conversion of two different curing protocols used during adhesive cementation. The following resin luting agents were tested: Hri Flow (MF) and pre-heated Hri Micerium (MH); light-cure Nexus Third Generation (NX3L) and dual-cure Nexus Third Generation (NX3D); dual cured RelyX Ultimate (RXU) and light-cure RelyX Veneers (RXL). For each tested material, ten samples were prepared and divided into two groups which had different curing protocols (P1 and P2): in P1, samples were cured for 40 s; in P2, samples were cured for 5 s, and then, after 20 s, cured again for additional 40 s. The degree of conversion (DC) was evaluated both during the first 5 min of the curing phase and after 1, 2, 7, 14 and 28 days (p = 0.05). Different trends were observed in DC values after 5 min by comparing P1 and P2. In both P1 and P2, DC decreased as follows, MH > MF > NX3L > RXL > RXU > NX3D. There were significant differences of DC values among all resin luting agents (p < 0.05) in P1, while no significant differences existed between MH and MF, and NX3L and RXL in P2. At 1, 2, 7, 14 and 28 days the light curing luting agents had a higher DC than the dual luting agents (p < 0.05). P1 and P2 were not statistically different at each time point (p > 0.05). Both P1 and P2 protocols let achieve an acceptable DC after 28 days. The tested P2 can be safely used to lute indirect restorations, simplifying the removal of cement excesses.


Asunto(s)
Cementación , Cementos Dentales , Materiales Dentales , Ensayo de Materiales , Cementos de Resina
17.
Biomed Res Int ; 2020: 1965818, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32382532

RESUMEN

The polishing procedure is commonly performed after direct composite restorations, and little information exists regarding the right timing during which it should be performed on bulk fill composites. This study investigated the effect of polishing timing on the degree of conversion (DC), Vickers microhardness (VMH), and surface morphology of a methacrylate- (MET-) and dimethacrylate- (DMET-) based bulk fill composite, by using FT-NIR, microhardness tester, and SEM. Composite samples were divided as follows: in Group I (immediate), samples were polished immediately after curing (t 0); in Group D (delayed), samples were polished after 24 h from curing (t 24), whereas the unpolished samples were considered as controls (Group C). The DC and VMH values were evaluated before and after polishing, at t 0 and t 24. Statistical analysis was performed with a significance level set at p < 0.05. At t 0, DC increased after polishing in both tested composites (p < 0.05), while at t 24, Group I and Group D were not different. By considering VMH, in the case of MET, all groups were not different both at t 0 and t 24. On the other hand, at t 0, VMH values of DMET increased after polishing. At t 24, DMET Group I and DMET Group D were not different. Qualitative evaluations of scanning electron micrographs showed that the surface morphology of MET presented a more irregular aspect than the DMET one. In summary, since the immediate polishing of MET can improve the DC, without negatively affecting VMH, but showing an irregular surface, it is suggested to wait 24 hours before proceeding with polishing. Otherwise, for DMET, the immediate polishing could definitively be recommended, since it improves both DC and VMH, also producing a regular surface. Therefore, clinicians may always safely polish a restoration performed using DMET-based bulk fill composites in one-chair appointment, avoiding a second appointment.


Asunto(s)
Resinas Compuestas/química , Ensayo de Materiales , Metacrilatos/química , Dureza
18.
Minerva Stomatol ; 69(4): 207-214, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31633320

RESUMEN

BACKGROUND: Finishing and polishing procedures play a crucial role to achieve the best aesthetic result of direct restorations. Many manufacturers to the clinicians offer different finishing and polishing systems. This study aims to examine the behavior of four different finishing and polishing systems on the roughness, gloss and morphology surface of one resin composite. METHODS: Twelve Filtek XTE Supreme (3M ESPE) discs were prepared and divided into 4 groups (N.=3), depending on the different finishing and polishing systems: Group 1 (GP1) Sof-Lex Extra-Thin XT discs; Group 2 (GP2) Sof-Lex Coarse black disc, multi-fluted bur, Sof-Lex Diamond Polishing System Spirals; Group 3 (GP3) Sof-Lex Coarse black disc, multi-fluted bur, Sof-Lex Diamond Polishing System Spirals, Diamond Twist SCL; Group 4 (GP4) with Sof-Lex Coarse black disc, multi-fluted bur and Occlubrush. The roughness and gloss were evaluated and then samples examined by Scanning Electron Microscopy (SEM) to analyse the morphology after finishing and polishing. RESULTS: Regarding the surface roughness, GP1 and GP2 showed similar values for Ra, Ry, Rz and Rq parameters; while GP3 displayed the lowest values in all parameters; GP4 had the highest Ra value. Regarding the gloss, the values decreased as follows: GP3>GP2=GP4>GP1 (P<0.05). Scanning electron micrographs showed the abrasion of the samples with an increase in the surface roughness in GP1 and GP4. One-way ANOVA followed by Tukey's Test was used for statistical evaluations (P<0.05). CONCLUSIONS: The roughness and gloss surface of resin composites depend on the finishing and polishing systems used. This study demonstrates that satisfactory gloss outcomes are obtained using a system based on diamond paste.


Asunto(s)
Pulido Dental , Estética Dental , Resinas Compuestas , Ensayo de Materiales , Propiedades de Superficie
19.
Front Physiol ; 10: 632, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31191341

RESUMEN

Aim: This study aimed to evaluate the anti-inflammatory effect and the incidence of adverse effects of an all-natural polyherbal mouthwash in patients with periodontitis, after 3 months of use. These aims were accomplished by using full mouth bleeding score (FMBS), full mouth plaque score (FMPS), probing depth (PD) clinical attachment level (CAL) and a questionnaire recording any adverse events. Methods: The present randomized controlled clinical study considered 40 patients with moderate or severe periodontitis, randomized in two groups: a test group (TG) and a control group (CG). TG was instructed to use a polyherbal mouthwash composed of Propolis resin extract, Plantago lanceolata, Salvia officinalis leaves extract, and 1.75% of essential oils and the CG was given a placebo mouthwash. Both groups were instructed to rinse for 2 min, twice daily after their routine oral home care with the different mouthwashes. Clinical measurements of FMBS, FMPS, PD and CAL were recorded at baseline (T0) and after 3 months (T1). The incidence of adverse outcomes was recorded at every follow-up. Mann-Whitney U test and Wilcoxon signed-rank test were used for the statistical analysis (p < 0.05). Results: The final study sample consisted of 34 healthy individuals, 17 individuals in each of the two groups. TG and CG showed a statistically significant reduction in FMBS (p = 0.001 TG; p = 0.002 CG), FMPS (p = 0.001 TG; p = 0.003 CG), PD (p = 0.001 TG; p = 0.011 CG) and CAL (p < 0.001 TG; p = 0.020 CG) values from baseline to 3 months. The TG showed a statistically significant decrease in FMBS and FMPS compared with the CG. No adverse events or side effects were reported or observed in both groups. Conclusion: The use of polyherbal mouthwash in patients with moderate or severe periodontitis has proved safe and effective in reducing bleeding score and plaque accumulation, after 3 months, compared with placebo, although no difference between the two groups were reported on PD and CAL (both improving at T1).

20.
Analyst ; 143(14): 3317-3326, 2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-29931010

RESUMEN

In the present study, human primary oral squamous carcinoma cells treated with cisplatin and 5-fluorouracil were analyzed, for the first time, by in vitro FTIR Microspectroscopy (FTIRM), to improve the knowledge on the biochemical pathways activated by these two chemotherapy drugs. To date, most of the studies regarding FTIRM cellular analysis have been executed on fixed cells from immortalized cell lines. FTIRM analysis performed on primary tumor cells under controlled hydrated conditions provides more reliable information on the biochemical processes occurring in in vivo tumor cells. This spectroscopic analysis allows to get on the same sample and at the same time an overview of the composition and structure of the most remarkable cellular components. In vitro FTIRM analysis of primary oral squamous carcinoma cells evidenced a time-dependent drug-specific cellular response, also including apoptosis triggering. Furthermore, the univariate and multivariate analyses of IR data evidenced meaningful spectroscopic differences ascribable to alterations affecting cellular proteins, lipids and nucleic acids. These findings suggest for the two drugs different pathways and extents of cellular damage, not provided by conventional cell-based assays (MTT assay and image-based cytometry).


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Escamosas/patología , Cisplatino/farmacología , Fluorouracilo/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Apoptosis , Humanos , Células Tumorales Cultivadas/efectos de los fármacos
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