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1.
J Am Dent Assoc ; 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39488773

RESUMO

BACKGROUND: A high level of scientific evidence supports several nonrestorative strategies for the control of caries, with the goal of reducing progression of mineral loss and arresting existing lesions. The authors provide an overview of evidence for nonrestorative caries control and considerations in the decision making for selecting nonrestorative options. TYPES OF STUDIES REVIEWED: The authors discuss findings from existing reviews, systematic reviews, and evidence-based guidelines (particularly from the American Dental Association) describing the effectiveness of nonrestorative strategies available in the US market for remineralization and arrest of caries lesions. RESULTS: Studies support a wide range of products for arresting caries lesions, such as fluorides, sealants, infiltration resins, and chlorhexidine varnish, among others, depending on the tooth surface, primary or permanent dentition, and whether lesions are noncavitated or cavitated. Decisions should be based on appropriate detection, diagnosis, and risk assessment. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Effective nonrestorative strategies should be used to manage active, noncavitated caries lesions in primary and permanent teeth, and can be considered for managing active cavitated lesions when restorative intervention is not feasible. These lesion-centered interventions should be part of the required overall management of the caries disease process and existing modifiable risk variables at the patient level. They must be monitored over time and reapplied periodically, as needed.

2.
Phys Chem Chem Phys ; 26(36): 23703-23709, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39225706

RESUMO

The recent interstellar detection of individual polycyclic aromatic hydrocarbons (PAHs) in the dense molecular cloud TMC-1 brings interest in related species that could be present in this astronomical environment. These detections, that include pure PAHs and their cyano-derivative counterparts, were performed through the interplay between laboratory rotational spectroscopy experiments and radioastronomical observations. Here, we present the laboratory rotational spectroscopic study of the five cyano-derivatives of the PAH fluorene (C13H10). The samples for these five species were synthetized in the laboratory and then characterized in the gas phase using a chirped-pulse Fourier-transform microwave spectrometer operating between 2 and 12 GHz. The analysis of the rotational spectra allowed us to derive accurate molecular constants for the five isomers used to obtain frequency predictions that enable astronomical searches of these molecules in the interstellar medium.

3.
J Phys Chem Lett ; 15(29): 7411-7418, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38995886

RESUMO

The interplay between laboratory rotational spectroscopy and radio astronomical observations provides the most effective procedure for identifying molecules in the interstellar medium (ISM). Following the recent interstellar detections of several Polycyclic Aromatic Hydrocarbons (PAHs) and cyano derivatives in the dense molecular cloud TMC-1, it is reasonable to consider searching for other cyano-PAHs in this astronomical source. We present a rotational spectroscopy investigation of the two cyano derivatives of the PAH biphenylene, a plausible reaction product of interstellar benzyne. The rotational spectrum provided molecular parameters for the parent species and 14 monosubstituted isotopologues for each isomer. An accurate equilibrium structure was determined for both isomers using Watson's mass-dependence method (rm(2)), offering information on its uncommon ring union. Astronomical searches for the cyanobiphenylene isomers have been undertaken in TMC-1, using the QUIJOTE line survey. No lines of any isomer were found in this astronomical source, but the experimental data will serve to enable future searches for these species in the ISM.

4.
Pediatr Dent ; 46(1): 8-12, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449039

RESUMO

Purpose: To assess the effectiveness of 38 percent silver diamine fluoride (SDF) in arresting cavitated caries lesions in young U.S. children. Methods: Children 12 to 71 months of age with severe early childhood caries participated in this phase three, multicenter, randomized, placebocontrolled trial. SDF was applied twice (at baseline and six months), and children were followed for eight months. A planned interim analysis of only the six-month primary outcome caries arrest data, for approximately half of the cohort (680 of 1,144 children), was conducted using a generalized estimating equation model, accounting for non-independence among carious lesions within a patient. Results: Five hundred ninety-nine of the 680 participants, with 1,413 lesions, completed the six-month exam. Lesions in the SDF group demonstrated 54 percent arrest versus 21 percent in the placebo (P<0.001). Conclusions: Silver diamine fluoride was effective at arresting active cavitated lesions in this population, leading to the early stop of the trial. Final analyses of all data and other outcomes are currently underway.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Compostos de Amônio Quaternário , Criança , Humanos , Pré-Escolar , Cárie Dentária/prevenção & controle , Compostos de Prata/uso terapêutico , Fluoretos Tópicos
5.
AJR Am J Roentgenol ; 222(6): e2430927, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38506538

RESUMO

In this 10-patient prospective pilot study, we show the feasibility of pragmatic direct ex vivo measurement of gadolinium retention from group II gadolinium-based contrasts agents (GBCAs) in young patients after routine tooth extraction. This noninvasive method may support future research attempting to understand the link between GBCA exposure and clinical outcomes.


Assuntos
Meios de Contraste , Gadolínio , Humanos , Gadolínio/farmacocinética , Feminino , Masculino , Extração Dentária , Adolescente , Imageamento por Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Criança
6.
J Phys Chem A ; 127(41): 8602-8606, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37816148

RESUMO

Pure rotational transitions of methacrolein oxide (MACRO) were observed by Fourier-transform microwave spectroscopy. Among the four low-lying conformers existing within an energy window of 3 kcal/mol, only the lowest-energy conformer, the anti-trans conformer, was detected in a discharged jet of a 1,3-diiode-2-methylprop-1-ene and O2 mixture diluted in Ar. Nineteen pure rotational transitions, in the frequency range from 10 to 25 GHz, most of them showing A/E splitting due to the methyl-top internal rotation, were observed and analyzed by the XIAM program, yielding the internal rotation barrier of 559 cm-1, which very well agrees with a theoretically calculated value, 558 cm-1, at the CCSD(T)/cc-pVTZ level of theory.

7.
Sci Total Environ ; 904: 166873, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37689208

RESUMO

Mollusc rearing is a relevant global socioeconomic activity. However, this activity has faced severe problems in the last years in southeast Brazil. The mariculture scallop production dropped from 51,2 tons in 2016 to 10,2 tons in 2022 in the Baia da Ilha Grande (BIG; Rio de Janeiro). However, the possible causes of this collapse are unknown. This study aimed to analyze decadal trends of water quality in Nodipecten nodosus spat and adult production in BIG. We also performed physical-chemical and biological water quality analyses of three scallop farms and two nearby locations at BIG in 2022 to evaluate possible environmental stressors and risks. Scallop spat production dropped drastically in the last five years (2018-2022: mean ± stdev: 0.47 ± 0.45 million). Spat production was higher in colder waters and during peaks of Chlorophyll a in the last 13 years. Reduction of Chlorophyll a coincided with decreasing spat production in the last five years. Warmer periods (>27 °C) of the year may hamper scallop development. Counts of potentially pathogenic bacteria (Vibrios) and Escherichia coli were significantly higher in warmer periods which may further reduce scallop productivity. Shotgun metagenomics of seawater samples from the five studied corroborated these culture-based counts. Vibrios and fecal indicator bacteria metagenomic sequences were abundant across the entire study area throughout 2022. The results of this study suggest the collapse of scallop mariculture is the result of a synergistic negative effect of global warming and poor seawater quality.


Assuntos
Aquecimento Global , Pectinidae , Animais , Clorofila A , Brasil , Poluição da Água
8.
J Dent Hyg ; 97(4): 60-69, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37553276

RESUMO

Purpose Non-surgical periodontal therapy (NSPT) is considered to be fundamental in the treatment of periodontal disease. Advanced area specific instruments were designed to increase the clinician's ability to effectively access root furcation areas during NSPT. The purpose of this study was to explore clinical dental hygienists' familiarity, utilization, and perceived efficacy of advanced instruments in root furcation areas during NSPT.Methods A randomized sample (n=3,500) of licensed dental hygienists in Michigan was invited to participate in a paper-based, mail survey. The 10-item instrument consisted of demographic, multiple choice, Likert scale, and open-ended questions. Descriptive and inferential statistics were used to analyze the data.Results A total of 1,156 surveys were returned; 858 met the inclusion criteria for a response rate of 24.5%. Respondents who graduated between 2010-2020 than those who graduated between 1990-1999 were more likely to utilize advanced instruments and those who graduated in 1989 or earlier (16.0% and 19.9% respectively). Respondents familiar with advanced instruments were more likely to use them in furcation areas during NSPT than those less familiar with the instruments (95% CI [18.1, 29.6], p<0.001). Respondents who perceived advanced instruments to be effective in furcation areas were more likely to utilize them (95% CI [1.0, 8.0], p<0.05) during NSPT. Most respondents indicated that they became familiar with advanced instruments during their dental hygiene education or through continuing education courses.Conclusion Familiarity with advanced instruments and perceived efficacy of these instruments for accessing root furcations increased the likelihood of clinical dental hygienists utilizing them during NSPT. Dental hygiene education and continuing education programs should continue to provide opportunities for students and practicing clinicians to learn NSPT instrumentation techniques utilizing advanced instruments designed for furcation access.


Assuntos
Higienistas Dentários , Educação Continuada , Humanos , Higienistas Dentários/educação , Michigan , Estudantes , Inquéritos e Questionários , Atitude do Pessoal de Saúde
9.
J Am Dent Assoc ; 154(7): 551-566.e51, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37380250

RESUMO

BACKGROUND: An expert panel convened by the American Dental Association (ADA) Council on Scientific Affairs together with the ADA Science and Research Institute's program for Clinical and Translational Research conducted a systematic review and developed recommendations for the treatment of moderate and advanced cavitated caries lesions in patients with vital, nonendodontically treated primary and permanent teeth. TYPES OF STUDIES REVIEWED: The authors searched for systematic reviews comparing carious tissue removal (CTR) approaches in Ovid MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Trip Medical Database. The authors also conducted a systematic search for randomized controlled trials comparing direct restorative materials in Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform. The authors used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the certainty of the evidence and formulate recommendations. RESULTS: The panel formulated 16 recommendations and good practice statements: 4 on CTR approaches specific to lesion depth and 12 on direct restorative materials specific to tooth location and surfaces involved. The panel conditionally recommended for the use of conservative CTR approaches, especially for advanced lesions. Although the panel conditionally recommended for the use of all direct restorative materials, they prioritized some materials over the use of others for certain clinical scenarios. PRACTICAL IMPLICATIONS: The evidence suggests that more conservative CTR approaches may decrease the risk of adverse effects. All included direct restorative materials may be effective in treating moderate and advanced caries lesions on vital, nonendodontically treated primary and permanent teeth.


Assuntos
American Dental Association , Cárie Dentária , Estados Unidos , Humanos , Suscetibilidade à Cárie Dentária , Revisões Sistemáticas como Assunto , Cárie Dentária/terapia , Bases de Dados Factuais , Materiais Dentários
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 291: 122353, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36646042

RESUMO

A peptide linkage (CO)NH containing molecule, N-ethylformamide, was investigated by rotational spectroscopy in order to determine the molecular constants of its highest-energy conformer, cis-ac. Its rotational spectrum was observed in two different frequency ranges, in the 4-26 GHz frequency region using a Fourier transform microwave spectrometer and at millimeter wave frequencies between 75 and 116 GHz, employing a broadband high-resolution rotational spectrometer. The measurements at low frequencies allowed to resolve the hyperfine structure components due to nitrogen nuclear quadrupole coupling while the data at higher frequencies provided spectroscopic information about high order centrifugal effects. From a merged fit using all the observational data we have determined a total of thirteen molecular constants that provide a more accurate spectral modelling of the cis-ac conformer and serves a basis for their astronomical search. We have also observed spectra of five singly substituted isotopologues for the cis-ac conformer, three 13C and one for each of 15N and the deuterated species on the N-D position, from which we derived a partial r0 structure, in fair agreement with an ab initio result. In addition, the rotational transitions of the deuterated species of the most stable trans-sc conformer were observed and assigned and three rotational, five centrifugal distortion constants and nuclear quadrupole coupling constants of the nitrogen and deuterium nuclei were determined.

11.
J Am Dent Assoc ; 154(2): e1-e98, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36610925

RESUMO

BACKGROUND: The goal of restoring caries lesions is to protect the pulp, prevent progression of the disease process, and restore the form and function of the tooth. The purpose of this systematic review was to determine the effect of different direct restorative materials for treating cavitated caries lesions on anterior and posterior primary and permanent teeth. TYPE OF STUDIES REVIEWED: The authors included parallel and split-mouth randomized controlled trials comparing the effectiveness of direct restorative materials commercially available in the United States placed in vital, nonendodontically treated primary and permanent teeth. Pairs of reviewers independently conducted study selection, data extraction, and assessments of risk of bias and certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. The authors conducted pair-wise meta-analyses to summarize the evidence and calculated measures of association and their 95% CIs. RESULTS: Thirty-eight randomized controlled trials were eligible for analysis, which included data on Class I and Class II restorations on primary teeth and Class I, Class II, Class III, Class V, and root surface restorations on permanent teeth. Included studies assessed the effect of amalgam, resin composite, compomer, conventional glass ionomer cement, resin-modified glass isomer cement, and preformed metal crowns. Moderate to very low certainty evidence suggested varying levels of effectiveness across restorative materials. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Owing to a relatively low event rate across various outcomes indicating restoration failure, there was limited evidence to support important differences between direct restorative materials used in practice.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Estados Unidos , Humanos , American Dental Association , Suscetibilidade à Cárie Dentária , Materiais Dentários/uso terapêutico , Cárie Dentária/prevenção & controle , Resinas Compostas , Dente Decíduo , Cimentos de Ionômeros de Vidro/uso terapêutico
12.
ACS Biomater Sci Eng ; 9(1): 318-328, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36519632

RESUMO

Cariogenic biofilms produce strong acidic microenvironments, which is the primary cause of dental caries. Streptococcus mutans is a dominant species in cariogenic biofilms. Herein, we report a pH-responsive, charge-switching smart copolymer to selectively target and eradicate bacteria in cariogenic biofilms. To that end, the copolymer is designed to be activated in an acidic environment. The smart copolymer, Poly-1A, consists of ternary compositions of monomers with a cationic ethyl ammonium group, a carboxylic group, and a hydrophobic group in the side chains. The net charge of Poly-1A was charge neutral at neutral pH, but it switched to be cationic because the acidic carboxylate side chains were protonated and became neutral; however, the ammonium groups remained positive. Poly-1A with a net positive charge bound to the anionic surface of oral bacteria by electrostatic interactions and disrupted the bacterial membranes, causing bacterial death. Poly-1A reduced the cell viability of planktonic and biofilm S. mutans at pH 4.5, while it was not bactericidal at pH 7.4. Poly-1A did not reduce the cell viability of human gingival fibroblasts and periodontal ligament stem cells for a 1 h incubation.


Assuntos
Anti-Infecciosos , Cárie Dentária , Polímeros Responsivos a Estímulos , Humanos , Streptococcus mutans , Biofilmes , Polímeros/farmacologia , Polímeros/química
13.
Phys Chem Chem Phys ; 24(41): 25099-25105, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36205179

RESUMO

Fourier transform microwave spectra for two isomers of the chlorine substituted vinyl radical have been observed in the 4-52 GHz frequency region. The observed radicals (2A') have been generated using electric discharges of diluted dichloro derivatives of ethylene as molecular precursors. Fine and hyperfine components observed for each rotational transition are fully assigned in the present study to two isotopologues (35Cl and 37Cl), and precise molecular constants are determined for both radicals.

14.
Caries Res ; 56(4): 419-428, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36162361

RESUMO

Previous work has shown targeted fluorescent starch nanoparticles (TFSNs) can label the subsurface of carious lesions and assist dental professionals in the diagnostic process. In this study, we aimed to evaluate the potential of using artificial intelligence (AI) to detect and score carious lesions using ICDAS in combination with fluorescent imaging following application of TFSNs on teeth with a range of lesion severities, using ICDAS-labeled images as the reference standard. A total of 130 extracted human teeth with ICDAS scores from 0 to 6 were selected by a calibrated cariologist. Then, the same surface was imaged with a stereomicroscope under white light illumination, without visible fluorescence, and blue light illumination with an orange filter following application of the TFSNs. Both sets of images were labeled by another blinded ICDAS-calibrated cariologist to demarcate lesion position and severity. Convolutional neural networks, state-of-the-art models in imaging AI, were trained to determine the presence, location, ICDAS score (severity), and lesion surface porosity (as an indicator of activity) of carious lesions, and tested by 30 k-fold validation for white light, blue light, and the combined image sets. The best models showed high performance for the detection of carious lesions (sensitivity 80.26%, PPV 76.36%), potential for determining the severity via ICDAS scoring (accuracy 72%, SD 5.67%), and the detection of surface porosity as an indicator of the activity of the lesions (accuracy 90%, SD 7.00%). More broadly, the combination of targeted biopolymer nanoparticles with imaging AI is a promising combination of novel technologies that could be applied to many other applications.


Assuntos
Cárie Dentária , Nanopartículas , Humanos , Suscetibilidade à Cárie Dentária , Inteligência Artificial , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Redes Neurais de Computação
15.
J Dent ; 125: 104243, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35907441

RESUMO

OBJECTIVES: We have previously shown fluorescent cationic starch nanoparticles (FCSNs) penetrate enamel surface porosity of active carious lesions, potentially aiding their detection. Here, we evaluate the in vitro diagnostic accuracy of FCSNs in detecting occlusal caries compared to histologic reference standard. METHODS: 100 extracted human teeth were selected with sound (50), or either non-cavitated (25) or cavitated (25) lesions. A region of interest (ROI) on the occlusal surface was assessed for fluorescence by two independent examiners, after immersion in FCSN solution, water rinse, and illumination by dental curing lamp viewed through orange UV-filter glasses. ROIs were sectioned and evaluated by histology (Downer Criteria) as a gold standard for caries presence. Cohen's Kappa was determined for inter- and intra-examiner agreement, and sensitivity, specificity, and area under the curve of Receiver Operator Curves (ROCAUC) were calculated. The analysis was repeated for the subset of "early" lesions, defined as being limited to enamel. RESULTS: FCSN use resulted in substantial inter-user (k=0.74±0.07), and high intra-user agreement (k=0.80±0.06; 0.94±0.03, by examiner). Sensitivity, specificity and ROCAUC for FCSNs were 88.9%; 94.6%; 0.92±0.06 for all, and 76.9%, 94.6%, and 0.86±0.10 for early lesions. In post hoc analysis, sensitivity seemed to be greater with the FCSN than the expert visual exam, particularly for early lesions. CONCLUSIONS/CLINICAL SIGNIFICANCE: FCSNs are a reproducible and accurate novel technology for occlusal caries detection, with high sensitivity and specificity compared to histology. Future clinical validation is necessary. FCSNs can improve early caries detection and shift treatment towards non-invasive approaches, improving oral health.


Assuntos
Cárie Dentária , Nanopartículas , Cárie Dentária/diagnóstico , Suscetibilidade à Cárie Dentária , Fluorescência , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Amido , Água
16.
Arch Oral Biol ; 135: 105368, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35151028

RESUMO

OBJECTIVE: It is unclear whether tea infusions with or without sucrose supplementation alter oral biofilm development, so we evaluated the effect of unsweetened and sucrose-sweetened black and green tea infusions on in vitro saliva-derived biofilms. DESIGN: Biofilms were developed from human saliva for 20 h in cell-free 25% human saliva within static glass-bottom microplates. During biofilm development, biofilms were treated with either (i) unsweetened black tea, (ii) unsweetened green tea, (iii) 10% sucrose-sweetened black tea, (iv) 10% sucrose-sweetened green tea (v) deionized water (negative control), or (vi) 10% sucrose (positive control). Biofilms were incubated at 37 °C in 5% CO2. After 20 h of development, biofilms were imaged using a CLSM, and biofilm architecture and viability were evaluated. RESULTS: All the tea infusions reduced biofilm biomass and altered some other biofilm architectural outcomes (e.g., biofilm surface area) compared to the control groups. Statistically significant differences in biofilm biomass, number of objects, surface area, and convex-hull porosity were observed between biofilms treated with green and black tea. The addition of sugar to tea did not significantly modify the ability of tea to alter biofilm architecture. Only the treatment of biofilms with unsweetened black tea significantly reduced bacterial viability. CONCLUSIONS: While both teas reduced biofilm biomass and altered biofilm architecture, black tea had an enhanced effect that may relate to this tea's observed antimicrobial activity. The addition of sucrose to tea infusions did not appear to reduce the impact of either tea in modifying oral biofilm architecture.


Assuntos
Camellia sinensis , Chá , Biofilmes , Humanos , Saliva , Sacarose/farmacologia
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120844, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35007907

RESUMO

Dinitriles with a saturated hydrocarbon skeleton and a -C≡N group at each end can have large electric dipole moments. Their formation can be related to highly reactive radicals such as CH2CN, C2N, or CN. Thus, these saturated dinitriles are potential candidates to be observed in the interstellar medium. In this work, two members of this family, hexanedinitrile and heptanedinitrile, have been investigated through their rotational spectra. The jet-cooled broadband chirped-pulse Fourier transform microwave spectra of both molecules were measured in the 2-8 GHz frequency region. Three and six conformers of hexanedinitrile and heptanedinitrile, respectively, were detected and assigned based on the rotational and quadrupole coupling constants.


Assuntos
Micro-Ondas , Análise de Fourier , Conformação Molecular , Nitrilas , Análise Espectral
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120846, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35033807

RESUMO

Methyl vinyl ketone is one of the major oxidation products of isoprene, and therefore, an important precursor of secondary organic aerosol. Understanding its interactions with water is relevant to gain insight into aerosol formation and improve the predictive power of atmospheric chemistry models. The molecular complex formed between methyl vinyl ketone and water has been generated in a supersonic jet and characterized using high-resolution microwave spectroscopy in combination with quantum chemistry calculations. In this study, we show that methyl vinyl ketone interacts with water forming four 1:1 isomers connected by O - H···O and C - H···O hydrogen bond interactions. Water has been found to preferentially bind to the antiperiplanar conformation of methyl vinyl ketone. Evidence of a large amplitude motion arising from the methyl internal rotation has been found in the rotational spectra of the dimer. The threefold methyl internal rotation barrier heights have been further determined and discussed for all the species.


Assuntos
Butanonas , Água , Ligação de Hidrogênio , Conformação Molecular
19.
J Appl Microbiol ; 132(2): 855-871, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34216534

RESUMO

Numerous in vitro biofilm model systems are available to study oral biofilms. Over the past several decades, increased understanding of oral biology and advances in technology have facilitated more accurate simulation of intraoral conditions and have allowed for the increased generalizability of in vitro oral biofilm studies. The integration of contemporary systems with confocal microscopy and 16S rRNA community profiling has enhanced the capabilities of in vitro biofilm model systems to quantify biofilm architecture and analyse microbial community composition. In this review, we describe several model systems relevant to modern in vitro oral biofilm studies: the constant depth film fermenter, Sorbarod perfusion system, drip-flow reactor, modified Robbins device, flowcells and microfluidic systems. We highlight how combining these systems with confocal microscopy and community composition analysis tools aids exploration of oral biofilm development under different conditions and in response to antimicrobial/anti-biofilm agents. The review closes with a discussion of future directions for the field of in vitro oral biofilm imaging and analysis.


Assuntos
Biofilmes , Microbiota , Antibacterianos , Reatores Biológicos , RNA Ribossômico 16S
20.
Caries Res ; 55(6): 585-593, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34610601

RESUMO

This laboratory study investigated the impact of tooth age on dental erosion susceptibility and preventive treatment efficacy. Extracted human premolars were selected and had their age estimated (∼10-100 years old) using established dental forensic methods. Enamel and root dentin slabs were prepared, embedded in acrylic blocks, flattened, and polished. The specimens were randomly assigned to one of three treatments (n = 93): Sn+F (800 ppm Sn as SnCl2 and 250 ppm F as NaF, pH 4.5), NaF (250 ppm F, pH 4.5), or deionized water (DIW). Each specimen was subjected for 10 days to a daily cycling protocol consisting of six 5-min erosive challenges (0.3% citric acid, pH 2.6), six 60-min remineralization periods (artificial saliva), and three 2-min treatments with the test solutions. Surface loss (SL) was measured after 3, 5, and 10 days, using optical profilometry. Effects of tooth age, antierosive treatment, and time on SL were evaluated using linear mixed effects regression analysis. SL increased with age for all substrate-treatment-time combinations (p < 0.0001). Sn+F and NaF solutions significantly reduced SL compared to DIW, regardless of substrate, time, or age (p < 0.0001), with best results shown for Sn+F. Efficacy of Sn+F increased with tooth age on enamel, but tooth age did not affect the efficacy of NaF on enamel. For dentin, increased efficacy was observed with age after 5 (for Sn+F) and 10 days (for Sn+F and NaF). In conclusion, increase of tooth age rendered enamel and root dentin more susceptible to dental erosion. NaF preventive efficacy improved with tooth age for dentin, in advanced erosion simulation. Sn+F reduced enamel SL due to erosion regardless of tooth age.


Assuntos
Erosão Dentária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Esmalte Dentário , Fluoretos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Fluoreto de Sódio , Erosão Dentária/prevenção & controle , Resultado do Tratamento , Adulto Jovem
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