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2.
Pediatr Dent ; 46(3): 192-198, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38822501

RESUMO

Purpose: The purposes of this study were to evaluate the effect of silver diammine fluoride (SDF) on the shear bond strength (SBS) of pink opaquer (PO) compared to resin-modified glass ionomer (RMGI) and conventional composite (COMP) on demineralized dentin, and also to investigate the mode of failure (MOF). Methods: Sixty extracted third molars were prepared, demineralized for 14 days, and divided into four groups: (1) COMP; (2) SDF+PO; (3) SDF+RMGI; and (4) SDF+COMP (restoration size: two by two mm). SBS, MOF, modified adhesive remnant index (MARI), and remnant adhesive volume (RAV) were evaluated using an Instron® machine, light microscopy, 3D digital scanner ( 3Shape©), and GeoMagic Wrap© software. Results: There was no significant difference in SBS (MPa) among the COMP mean??standard deviation (2.5±1.59), SDF+COMP (2.28±1.05), SDF+PO (3.31±2.63), and SDF+RMGI groups (3.74±2.34). There was no significant difference in MOF and MARI among the four groups (P>0.05). There was no significant difference in RAV (mm3) among the COMP (0.5±0.33), SDF+COMP (0.39±0.44), SDF+PO (0.42±0.38), and SDF+RMGI groups (0.42±0.38; P>0.05). A significant correlation existed between MOF and RAV (R equals 0.721; P<0.001). MOF, MARI, and RAV did not show any correlations with SBS (P>0.05). Conclusions: Silver diammine fluoride does not affect shear bond strength between carious dentinal surface and tooth color restorative materials. The amount of material left on the interface is not related to the amount of shear force needed to break the restoration.


Assuntos
Resinas Compostas , Colagem Dentária , Dentina , Fluoretos Tópicos , Resistência ao Cisalhamento , Compostos de Prata , Humanos , Compostos de Prata/química , Dentina/efeitos dos fármacos , Resinas Compostas/química , Cimentos de Ionômeros de Vidro/química , Compostos de Amônio Quaternário/química , Teste de Materiais , Restauração Dentária Permanente/métodos , Materiais Dentários/química , Análise do Estresse Dentário , Desmineralização do Dente/prevenção & controle , Técnicas In Vitro , Resinas Acrílicas/química , Cor
3.
BMC Oral Health ; 24(1): 657, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840138

RESUMO

BACKGROUND: Margin designs and loading conditions can impact the mechanical characteristics and survival of endocrowns. Analyzing the stress distribution of endocrowns with various margin designs and loading conditions can provide evidence for their clinical application. METHODS: Three finite element analysis models were established based on the margin designs: endocrown with a butt-joint type margin (E0), endocrown with a 90° shoulder (E90), and endocrown with a 135° shoulder (E135). The E0 group involved lowering the occlusal surface and preparing the pulp chamber. The E90 group created a 90° shoulder on the margin of model E0, measuring 1.5 mm high and 1 mm wide. The E135 group featured a 135° shoulder. The solids of the models were in fixed contact with each other, and the materials of tooth tissue and restoration were uniform, continuous, isotropic linear elasticity. Nine static loads were applied, with a total load of 225 N, and the maximum von Mises stresses and stress distribution were calculated for teeth and endocrowns with different margin designs. RESULTS: Compared the stresses of different models under the same loading condition. In endocrowns, when the loading points were concentrated on the buccal side, the maximum von Mises stresses were E0 = E90 = E135, and when there was a lingual loading, they were E0 < E90 = E135. In enamel, the maximum von Mises stresses under all loading conditions were E0 > E90 > E135. In dentin, the maximum von Mises stresses of the three models were basically similar except for load2, load5 and load9. Compare the stresses of the same model under different loading conditions. In endocrowns, stresses were higher when lingual loading was present. In enamel and dentin, stresses were higher when loaded obliquely or unevenly. The stresses in the endocrowns were concentrated in the loading area. In enamel, stress concentration occurred at the cementoenamel junction. In particular, E90 and E135 also experienced stress concentration at the shoulder. In dentin, the stresses were mainly concentrated in the upper section of the tooth root. CONCLUSION: Stress distribution is similar among the three margin designs of endocrowns, but the shoulder-type designs, especially the 135° shoulder, exhibit reduced stress concentration.


Assuntos
Análise do Estresse Dentário , Análise de Elementos Finitos , Estresse Mecânico , Humanos , Análise do Estresse Dentário/métodos , Planejamento de Prótese Dentária , Coroas , Fenômenos Biomecânicos , Dentina
4.
Forensic Sci Int ; 360: 112061, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824866

RESUMO

INTRODUCTION: Teeth are biological structures with a high degree of hardness, density, calcification, and capacity to adapt to extrinsic factors at physical, biological, and physiological levels. Subsequently, they resist for a longer period in deteriorating environmental conditions. With dental analysis, it is possible to acquire biographical data about a person. The aim of this scoping review was to identify publications using human teeth tissues to estimate sexual dimorphism. METHODS: The scoping review was carried out in the following databases: Jstor, Scielo, Science Direct, PubMed, and Scopus, using ten search strategies in English and guaranteeing completeness and reproducibility of the phases stipulated in the PRISMA guide. RESULTS: 143 studies on sexual dimorphism based on dental tissue traits were included, of which 40.6% (n = 58) were done in Asia and 27.2% (n = 39) in America. 80% of the studies (equivalent to 114 articles) focused their observations and measurements on the dental crown; 4.2% in enamel, dentin, and pulp together; 3.5% in dental pulp; 2.1% in the entire tooth; 2.8% in enamel, root, and the enamel-cementum junction, and only 0.7% in dentin and pulp. In addition, 92.3% of the studies used metric methods, while only 4.9% and 2.8% used biochemical and non-metric method respectively. CONCLUSION: For sexual dimorphism establishment, enamel has been the most analyzed dental tissue in permanent canines and molars mainly. Likewise, the most widely and accurately used methods for this purpose are the metrics, with the odontometry as the most implemented (intraoral or by using dental plaster models, digital scanning or software) with prediction percentages ranging from 51% to 95.9%. In contrast to biochemical methods, that can achieve the highest precision (up to 100%), the non-metric methods, to a less extent, reported prediction percentages of 58%.


Assuntos
Odontologia Legal , Caracteres Sexuais , Dente , Humanos , Odontologia Legal/métodos , Dentina , Esmalte Dentário , Polpa Dentária/diagnóstico por imagem
5.
BMC Oral Health ; 24(1): 667, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849778

RESUMO

BACKGROUND: This study investigated the effect of carbodiimide (EDC) combined with Clearfil SE self-etch adhesive on the shear bond strength (SBS), crosslinking degree, denaturation temperature, and enzyme activity of dentin in vitro. MATERIALS AND METHODS: Collected human sound third molars were randomly divided into different groups with or without EDC treatment (0.01-1 M). The specimens (n = 16)were stored for 24 h (immediate) or 12 months (aging) before testing the SBS. Fine dentin powder was obtained and treated with the same solutions. Then the crosslinking degree, denaturation temperature (Td), and enzyme activity were tested. Statistical analysis was performed using a one-way analysis of variance (ANOVA) to compare the differences of data between groups (α = 0.05). RESULTS: There was a significant drop in immediate SBS and more adhesive fracture of 1.0 M EDC group, while there were no significant differences among the other groups. SEM showed a homogeneous interface under all treatments. After 12 months of aging, the SBS significantly decreased. Less decreases of SBS in the 0.3 and 0.5 M groups were found. Due to thermal and enzymatical properties consideration, the 0.3 and 0.5 M treatments also showed higher cross-link degree and Td with lower enzyme activity. CONCLUSION: 0.3 and 0.5 M EDC may be favorable for delaying the aging of self-etch bond strength for 12 months. But it is still needed thoroughly study.


Assuntos
Carbodi-Imidas , Cimentos de Resina , Resistência ao Cisalhamento , Humanos , Carbodi-Imidas/química , Cimentos de Resina/química , Teste de Materiais , Dentina , Microscopia Eletrônica de Varredura , Adesivos Dentinários/química , Análise do Estresse Dentário , Reagentes de Ligações Cruzadas/química , Colagem Dentária/métodos , Técnicas In Vitro , Condicionamento Ácido do Dente/métodos , Dente Serotino , Temperatura , Fatores de Tempo , Propriedades de Superfície
6.
Med Sci Monit ; 30: e943353, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825814

RESUMO

BACKGROUND Dentin contamination with hemostatic agents before bonding indirect restorations negatively affects the bond strength. However, the consensus on which materials could be used to clean contamination of hemostatic agents has not been explored. The aim of this study was to assess the effect of Katana Cleaner applied on the surface of dentin contaminated with hemostatic agents on the shear bond strength (SBS) of self-adhesive resin cement by comparing it with three other surface cleaners. MATERIAL AND METHODS Ninety dentin specimens were divided into a no contamination group (control) (n=10), 4 groups contaminated with 25% aluminum chloride (Viscostat Clear) (n=40), and 4 groups contaminated with 20% ferric sulfate (Viscostat) (n=40). Subsequently, 4 different cleaners were used for each contamination group (water rinse, phosphoric acid, chlorhexidine, and Katana Cleaner). Then, self-adhesive resin cement was directly bonded to the treated surfaces. All specimens were subjected to 5000 thermal cycles of artificial aging. The shear bond strength was measured using a universal testing machine. RESULTS Two-way analysis of variance showed that the contaminant type as the main factor was statistically non-significant (p=0.655), cleaner type as the main factor was highly significant (p<0.001), and interaction between the contaminant and cleaner was non-significant (p=0.51). The cleaner type was the main factor influencing the bond strength. Phosphoric acid and chlorhexidine showed better performance than Katana Cleaner. CONCLUSIONS Cleaning dentin surface contamination with phosphoric acid and chlorhexidine had better performance than with Katana Cleaner.


Assuntos
Colagem Dentária , Dentina , Hemostáticos , Cimentos de Resina , Resistência ao Cisalhamento , Humanos , Dentina/efeitos dos fármacos , Hemostáticos/farmacologia , Colagem Dentária/métodos , Clorexidina/análogos & derivados , Clorexidina/farmacologia , Teste de Materiais/métodos , Propriedades de Superfície/efeitos dos fármacos , Adesivos Dentinários , Compostos Férricos/química
7.
BMC Oral Health ; 24(1): 678, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858636

RESUMO

OBJECTIVE: This systematic review aims to comparatively analyse the amount of dentin removal by free hand and static guided endodontics with dynamic navigation system (DNS) in endodontic access cavity preparation. METHODS: The systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Based on the structured PICO framework of "Comparative evaluation of dynamic navigation system (I) to freehand (C) and static guided endodontics (C) in endodontic access cavity preparation on the preservation of tooth structure (O) when assessed on permanent human teeth (P)", the keywords were formulated and the articles were retrieved from three databases namely PubMed, Scopus and Embase, based on the keywords from the time of inception of DNS till June 2023. The risk of bias assessment was done using a modified Joanne Briggs Institute checklist, which evaluated domains such as randomisation, sample size, image acquisition using CBCT, angulation, accuracy and time taken. As the data was heterogenous, a quantitative meta-analysis was not performed. RESULTS: Initially, 174 articles were retrieved from the three databases, 30 duplicates were removed, after title check 108 articles were excluded and following abstract check only 10 articles qualified for full text analysis. On reviewing the 10 full text articles, 5 articles were excluded and the remaining 5 articles were subjected to the risk of bias analysis which showed that 2 articles displayed low risk of bias and three articles showed high risk of bias. The RoB analysis revealed that only 2 studies evaluated the preservation of dentin in terms of accuracy, angulation and time taken proving the increased precision with minimal loss of tooth structure using DNS. In both the studies, DNS proved to be superior to free hand technique in terms of precision, accuracy and efficiency in locating the canals during access cavity preparation with maximal preservation of tooth structure. CONCLUSION: With the minimal literature evidences, the present systematic review highlights maximal preservation of dentin using DNS. However, further invitro and invivo studies comparing the free hand, static guided endodontics to DNS must be carried out for its translation into clinical practice. CLINICAL SIGNIFICANCE: Dynamic navigation system provides maximal preservation of dentin during access cavity preparation.


Assuntos
Dentina , Humanos , Dentina/diagnóstico por imagem , Preparo de Canal Radicular/métodos , Preparo de Canal Radicular/instrumentação
8.
BMC Oral Health ; 24(1): 681, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867263

RESUMO

BACKGROUND: Surface tension and contact angle properties, which play a crucial role in determining the effectiveness of irrigation solutions in penetrating dentin surfaces and dentin tubules, are highly important for the development of new irrigation solutions and their preferences. The aim of the current study was to compare the surface tension and contact angle properties of different irrigation solutions used in endodontics, both on the dentin surface and within dentin tubules. METHODS: In this study, the contact angles and surface tensions of 5.25% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), 5% boric acid (BA), 0.02% hypochlorous acid (HOCl), 0.2% chlorine dioxide (ClO2), Biopure MTAD, QMix solutions, and distilled water (control group) were measured. Measurements were conducted using a goniometer device (Attension Theta Lite Tensiometer, Biolin Scientific, USA), employing the sessile drop method for contact angle measurements on pre-prepared dentin surfaces, and the pendant drop method for surface tension. RESULTS: Contact angle measurements revealed no statistically significant differences between the contact angle values of MTAD, ClO2, and CHX or between NaOCl, QMix, BA, and HOCl (p > 0.05). However, EDTA exhibited a significantly greater contact angle than did MTAD, ClO2, CHX, NaOCl, QMix, BA, and HOCl (p < 0.05). Furthermore, the contact angle of dentin with distilled water was greater than that with all other solutions tested (p < 0.05). Surface tension measurements revealed that the surface tension values of QMix and MTAD were statistically similar (p > 0.05). CHX exhibited lower surface tension than distilled water and HOCl (p < 0.05), and it also had lower surface tension than ClO2, NaOCl, and BA (p < 0.05). Additionally, the surface tension of the samples treated with EDTA was greater than that of all other solutions tested (p < 0.05). CONCLUSION: The direct linear relationship between the surface tension of liquids and contact angles on different surfaces may not always hold true, and these values should be considered independently for each solution on various surfaces. Considering the contact angles and surface tension properties of irrigation solutions with root canal dentin, it can be suggested for clinical use that ClO2 could be recommended over NaOCl, and similarly, BA could be recommended over EDTA.


Assuntos
Dentina , Irrigantes do Canal Radicular , Tensão Superficial , Dentina/efeitos dos fármacos , Humanos , Hipoclorito de Sódio/farmacologia , Ácido Edético , Ácido Hipocloroso , Propriedades de Superfície
9.
Sci Rep ; 14(1): 13262, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858417

RESUMO

The purpose of this study was to evaluate the fatigue survival of 5Y-PSZ zirconia infiltrated with an experimental glass and bonded onto dentin analogues. Disc-shaped specimens of a 5Y-PSZ (Katana UTML Kuraray Noritake) were cemented onto dentin analogs (NEMA G10) and divided into four groups (n = 15): Zctrl Group (control, without infiltration); Zglz Group (Glaze, compression surface); Zinf-comp Group (Experimental Glass, compression surface); Zinf-tens Group (Experimental Glass, tension surface). Surface treatments were varied. Cyclic fatigue loading, oblique transillumination, stereomicroscope examination, and scanning electron microscopy were performed. Fatigue data were analyzed (failure load and number of cycles) using survival analysis (Kaplan-Meier and Log-Rank Mantel-Cox). There was no statistically significant difference in fatigue survival between the Zglz, Zctrl, and Zinf-comp groups. The Zinf-tens group presented a significantly higher failure load when compared to the other groups and exhibited a different failure mode. The experimental glass effectively infiltrated the zirconia, enhancing structural reliability, altering the failure mode, and improving load-bearing capacity over more cycles, particularly in the group where the glass was infiltrated into the tensile surface of the zirconia. Glass infiltration into 5Y-PSZ zirconia significantly enhanced structural reliability and the ability to withstand loads over an increased number of cycles. This approach has the potential to increase the durability of zirconia restorations, reducing the need for replacements and save time and resources, promoting efficiency in clinical practice.


Assuntos
Dentina , Vidro , Teste de Materiais , Zircônio , Zircônio/química , Vidro/química , Dentina/química , Humanos , Microscopia Eletrônica de Varredura , Propriedades de Superfície
10.
Braz Dent J ; 35: e245720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38775593

RESUMO

This study evaluated a new method of adhesive system application on the bond strength between fiber post and root dentin using two adhesive systems. The canals of sixty bovine incisors were prepared and obturated. The roots were divided into six groups (n=10) according to the adhesive system (Clearfil SE - CSE and Single Bond Universal - SBU) and the application strategy (microbrush - MB; rotary brush - RB; and ultrasonic tip - US). The glass fiber posts were cemented with resin cement (RelyX ARC). The roots were sectioned perpendicularly to their long axis, and three slices per root were obtained. Previously to the push-out test, confocal laser scanning microscopy (CLSM) was performed to illustrate the interfacial adaptation of the cement to the root canal walls. Failure patterns were analyzed with 40x magnification. Shapiro-Wilk indicated a normal distribution of the data. The bond strength values were compared using one-way ANOVA and Tukey's tests. Student's T test analyzed the differences between the adhesive systems within each third and protocol. A significance level of 5% was used. CSE with RB showed higher mean bond strength values compared to MB (conventional technique) (P < 0.05). US application resulted in intermediate bond strength values for CSE (P > 0.05). The application of SBU using RB generated higher mean bond strength values compared to MB and US (P < 0.05). Adhesive failures were predominant (65.5%). CSE and SBU application with the new rotary brush improved the bond strength of fiber posts to root dentin compared to the conventional strategy.


Assuntos
Dentina , Técnica para Retentor Intrarradicular , Cimentos de Resina , Bovinos , Animais , Cimentos de Resina/química , Colagem Dentária/métodos , Bis-Fenol A-Glicidil Metacrilato/química , Adesivos Dentinários/química , Microscopia Confocal , Ácidos Polimetacrílicos/química , Teste de Materiais , Vidro/química , Raiz Dentária , Polietilenoglicóis/química , Análise do Estresse Dentário
11.
PLoS One ; 19(5): e0304156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776324

RESUMO

Saliva substitutes with enhanced dentin remineralization properties were expected to help manage caries progression in patients with xerostomia. This in vitro study examined the rheological properties and remineralization action of experimental saliva substitutes containing propolis extract and aloe vera extract on demineralized dentin. Four experimental saliva substitutes were formulated with varying concentrations of propolis extract (P) and aloe vera extract (A) were prepared. A commercial saliva substitute (Biotene Oral Rinse) was used as a commercial comparison. The rheological properties and viscosity of these materials were measured using a strain-controlled rheometer (n = 3). The remineralizing actions of saliva substitutes on demineralized dentin after 2 weeks were determined using ATR-FTIR and SEM-EDX (n = 8). The results were expressed as a percentage increase in the mineral-to-matrix ratio. Biotene demonstrated a significantly higher viscosity (13.5 mPa·s) than experimental saliva substitutes (p<0.05). The addition of extracts increased the viscosity of the saliva substitutes from 4.7 mPa·s to 5.2 mPa·s. All formulations showed minimal shear thinning behavior, which was the viscoelastic properties of natural saliva. The formulation containing 5 wt% of propolis exhibited the highest increase in the median mineral-to-matrix ratio (25.48%). The SEM-EDX analysis revealed substantial mineral precipitation in demineralized dentin, especially in formulations with 5 wt% or 2.5 wt% of propolis. The effect of the aloe vera extract was minimal. The addition of propolis and aloe vera extracts increased the viscosity of saliva substitutes. the addition of propolis for 2.5 or 5 wt% to saliva substitutes increased mineral apatite precipitation and tubule occlusion. To conclude, the saliva substitute containing propolis extract demonstrated superior remineralizing actions compared with those containing only aloe vera extract.


Assuntos
Aloe , Dentina , Extratos Vegetais , Própole , Reologia , Saliva Artificial , Própole/química , Própole/farmacologia , Aloe/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Saliva Artificial/química , Dentina/química , Dentina/efeitos dos fármacos , Humanos , Viscosidade , Remineralização Dentária/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
12.
BMC Oral Health ; 24(1): 581, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764034

RESUMO

BACKGROUND: This study was conducted to compare chemical, elemental and surface properties of sound and carious dentin after application of two restorative materials resin-modified glassionomer claimed to be bioactive and glass hybrid restorative material after enzymatic chemomechanical caries removal (CMCR) agent. METHODS: Forty carious and twenty non-carious human permanent molars were used. Molars were randomly distributed into three main groups: Group 1 (negative control) - sound molars, Group 2 (positive control) - molars were left without caries removal and Group 3 (Test Group) caries excavated with enzymatic based CMCR agent. After caries excavation and restoration application, all specimens were prepared Vickers microhardness test (VHN), for elemental analysis using Energy Dispersive Xray (EDX) mapping and finally chemical analysis using Micro-Raman microscopy. RESULTS: Vickers microhardness values of dentin with the claimed bioactive GIC specimens was statistically higher than with glass hybrid GIC specimens. EDX analysis at the junction estimated: Calcium and Phosphorus of the glass hybrid GIC showed insignificantly higher mean valued than that of the bioactive GIC. Silica and Aluminum mean values at the junction were significantly higher with bioactive GIC specimens than glass hybrid GIC specimen. Micro-raman spectroscopy revealed that bioactive GIC specimens showed higher frequencies of v 1 PO 4, which indicated high level of remineralization. CONCLUSIONS: It was concluded that ion-releasing bioactive resin-based restorative material had increased the microhardness and remineralization rate of carries affected and sound dentin. In addition, enzymatic caries excavation with papain-based CMCR agent has no adverse effect on dentin substrate.


Assuntos
Cárie Dentária , Preparo da Cavidade Dentária , Dentina , Cimentos de Ionômeros de Vidro , Dureza , Humanos , Cárie Dentária/terapia , Cimentos de Ionômeros de Vidro/química , Preparo da Cavidade Dentária/métodos , Fósforo/análise , Papaína/uso terapêutico , Propriedades de Superfície , Restauração Dentária Permanente/métodos , Espectrometria por Raios X , Análise Espectral Raman , Cálcio/análise , Dente Molar , Remineralização Dentária/métodos , Alumínio , Dióxido de Silício , Teste de Materiais
13.
Clin Oral Investig ; 28(6): 324, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38761225

RESUMO

OBJECTIVES: To assess the growth of a multispecies biofilm on root canal dentin under different radiotherapy regimens. MATERIALS AND METHODS: Sixty-three human root dentin cylinders were distributed into six groups. In three groups, no biofilm was formed (n = 3): NoRT) non-irradiated dentin; RT55) 55 Gy; and RT70) 70 Gy. In the other three groups (n = 18), a 21-day multispecies biofilm (Enterococcus faecalis, Streptococcus mutans, and Candida albicans) was formed in the canal: NoRT + Bio) non-irradiated + biofilm; RT55 + Bio) 55 Gy + biofilm; and RT70 + Bio) 70 Gy + biofilm. The biofilm was quantified (CFUs/mL). Biofilm microstructure was assessed under SEM. Microbial penetration into dentinal tubules was assessed under CLSM. For the biofilm biomass and dentin microhardness pre- and after biofilm growth assessments, 45 bovine dentin specimens were distributed into three groups (n = 15): NoRT) non-irradiated + biofilm; RT55 + Bio) 55 Gy + biofilm; and RT70 + Bio) 70 Gy + biofilm. RESULTS: Irradiated specimens (70 Gy) had higher quantity of microorganisms than non-irradiated (p = .010). There was gradual increase in biofilm biomass from non-irradiated to 55 Gy and 70 Gy (p < .001). Irradiated specimens had greater reduction in microhardness after biofilm growth. Irradiated dentin led to the growth of a more complex and irregular biofilm. There was microbial penetration into the dentinal tubules, regardless of the radiation regimen. CONCLUSION: Radiotherapy increased the number of microorganisms and biofilm biomass and reduced dentin microhardness. Microbial penetration into dentinal tubules was noticeable. CLINICAL RELEVANCE: Cumulative and potentially irreversible side effects of radiotherapy affect biofilm growth on root dentin. These changes could compromise the success of endodontic treatment in oncological patients undergoing head and neck radiotherapy.


Assuntos
Biofilmes , Candida albicans , Cavidade Pulpar , Dentina , Enterococcus faecalis , Streptococcus mutans , Biofilmes/efeitos da radiação , Dentina/microbiologia , Dentina/efeitos da radiação , Humanos , Cavidade Pulpar/microbiologia , Cavidade Pulpar/efeitos da radiação , Candida albicans/efeitos da radiação , Animais , Enterococcus faecalis/efeitos da radiação , Streptococcus mutans/efeitos da radiação , Bovinos , Microscopia Eletrônica de Varredura , Dureza , Microscopia Confocal , Dosagem Radioterapêutica
14.
PLoS One ; 19(5): e0302334, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748638

RESUMO

Susceptibility to morbidity and mortality is increased in early life, yet proactive measures, such as breastfeeding and weaning practices, can be taken through specific investments from parents and wider society. The extent to which such biosocialcultural investment was achieved within 1st millennium BCE Etruscan society, of whom little written sources are available, is unkown. This research investigates life histories in non-adults and adults from Pontecagnano (southern Italy, 730-580 BCE) in order to track cross-sectional and longitudinal breastfeeding and weaning patterns and to characterize the diet more broadly. Stable carbon and nitrogen isotope analysis of incrementally-sampled deciduous and permanent dentine (n = 15), bulk bone collagen (n = 38), and tooth enamel bioapatite (n = 21) reveal the diet was largely based on C3 staple crops with marginal contributions of animal protein. Millet was found to play a role for maternal diet and trajectories of breastfeeding and feeding for some infants and children at the site. The combination of multiple isotope systems and tissues demonstrates exclusive breastfeeding was pursued until 0.6 years, followed by progressive introduction of proteanocius supplementary foods during weaning that lasted between approximately 0.7 and 2.6 years. The combination of biochemical data with macroscopic skeletal lesions of infantile metabolic diseases and physiological stress markers showed high δ15Ndentine in the months prior to death consistent with the isotopic pattern of opposing covariance.


Assuntos
Osso e Ossos , Isótopos de Carbono , Dieta , Isótopos de Nitrogênio , Humanos , Itália , Lactente , Dieta/história , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , História Antiga , Osso e Ossos/química , Feminino , Paleopatologia , Adulto , Desmame , Aleitamento Materno/história , Estresse Fisiológico , Dentina/química , Dentina/metabolismo , Colágeno/metabolismo , Colágeno/análise , Pré-Escolar , Masculino , Criança
15.
J Evid Based Dent Pract ; 24(2): 101969, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38821658

RESUMO

OBJECTIVES: This study assessed alterations in sensitivity among symptomatic noncarious cervical lesions (NCCLs) following the application of 3 low-level diode laser wavelengths before composite restoration. It analyzed the changes in dentin topography using a scanning electron microscope (SEM). MATERIALS AND METHODS: Nine patients with 36 NCCLs were randomly assigned intra-individually to 4 groups based on the laser wavelength: laser simulation, 445 nm, 660 nm, and 970 nm. Cavity preparation, irradiation, and composite restoration were performed for each lesion. Sensitivity to cold stimuli was recorded using a visual analog scale (VAS) before the intervention (baseline) and at 1 day, 14 days, 1-, 3-, and 6-month. Pulp sensibility was recorded using an electrical pulp tester (EPT) at baseline, before treatment, and at 3- and 6-month. Additionally, an in vitro examination was performed on 12 extracted human molars to yield 12 dentin discs. Each disc was randomly divided into 4 quadrants to receive the same laser wavelengths to determine the diameters of the tubules using SEM. Results were analyzed statistically for clinical studies by the Friedman test, while ANOVA (RM-ANOVA) was conducted in-vitro, followed by the Bonferroni test in the case of significance (P < .05). RESULTS: VAS readings decreased across all groups, with a significant decrease observed for 660 nm and 970 nm from 14 days to 6-month, while at 445 nm there was a significant decrease at 6-month compared to the control (P < .05). EPT showed a significant decrease in pain threshold levels at 660 nm and 970 nm at 3- and 6-month, while 445 nm showed a significant decrease at 6-month compared to the control (P < .05). The mean tubular diameter at 445 nm decreased, with no significant difference from the control, whereas a significant decrease was found at 660 nm and 970 nm compared to the control (P < .05). CONCLUSIONS: Prior to composite restoration in symptomatic NCCLs, diode lasers with a wavelength of 660 nm showed the highest reduction in sensitivity, followed by 970 nm, whereas 445 nm diode lasers showed the least reduction. Additionally, diode lasers with wavelengths of 660 and 970 nm reduced the width of the dentinal tubules (DT) without inducing melting, as viewed under SEM.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Sensibilidade da Dentina , Dentina , Lasers Semicondutores , Microscopia Eletrônica de Varredura , Humanos , Feminino , Restauração Dentária Permanente/métodos , Sensibilidade da Dentina/radioterapia , Lasers Semicondutores/uso terapêutico , Adulto , Masculino , Terapia com Luz de Baixa Intensidade/métodos , Colo do Dente/patologia , Adulto Jovem , Pessoa de Meia-Idade
16.
Biomater Adv ; 161: 213883, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38762928

RESUMO

Maintaining the viability of damaged pulp is critical in clinical dentistry. Pulp capping, by placing dental material over the exposed pulp, is a main approach to promote pulp-dentin healing and mineralized tissue formation. The dental materials are desired to impact on intricate physiological mechanisms in the healing process, including early regulation of inflammation, immunity, and cellular events. In this study, we developed an injectable dental pulp-derived decellularized matrix (DPM) hydrogel to modulate macrophage responses and promote dentin repair. The DPM derived from porcine dental pulp has high collagen retention and low DNA content. The DPM was solubilized by pepsin digestion (named p-DPM) and subsequently injected through a 25G needle to form hydrogel facilely at 37 °C. In vitro results demonstrated that the p-DPM induced the M2-polarization of macrophages and the migration, proliferation, and dentin differentiation of human dental pulp stem cells from deciduous teeth (SHEDs). In a mouse subcutaneous injection test, the p-DPM hydrogel was found to facilitate cell recruitment and M2 polarization during the early phase of implantation. Additionally, the acute pulp restoration in rat models proved that injectable p-DPM hydrogel as a pulp-capping agent had excellent efficacy in dentin regeneration. This study demonstrates that the DPM promotes dentin repair by modulating macrophage responses, and has a potential for pulp-capping applications in dental practice.


Assuntos
Polpa Dentária , Dentina , Hidrogéis , Macrófagos , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Animais , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Humanos , Dentina/efeitos dos fármacos , Dentina/química , Hidrogéis/química , Camundongos , Ratos , Matriz Extracelular Descelularizada/química , Matriz Extracelular Descelularizada/farmacologia , Suínos , Diferenciação Celular/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Cicatrização/efeitos dos fármacos
17.
Sci Rep ; 14(1): 12444, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816512

RESUMO

This preregistered ex vivo investigation examined the dentinal hybrid layer formation of a resinous infiltrant (Icon), with reference to both thickness (HLT) and homogeneity when combined with modified tunnel preparation (occlusal cavity only) and internal/external caries infiltration. The adhesives Syntac and Scotchbond MP were used as controls (Groups 1 and 3) or in combination with Icon (Groups 2 and 4). A split-tooth design using healthy third molars from 20 donors resulted in 20 prepared dentine cavities per experimental group. The cavity surfaces (n = 80) were etched (37% H3PO4), rinsed, and air-dried. Rewetting with ethanol was followed by application of the respective primers. After labeling with fluorescent dyes, either Syntac Adhesive/Heliobond or Scotchbond MP Adhesive was used alone or supplemented with Icon. HLT, as evaluated by scanning electron microscopy, did not significantly differ (P > 0.05), and confocal laser scanning microscopy revealed homogeneously mixed/polymerized resin-dentine interdiffusion zones in all groups. Icon can be successfully integrated into an ethanol-wet dentine bonding strategy, and will result in compact and homogeneous hybrid layers of comparable thickness considered equivalent to the non-Icon controls, thus allowing for preservation of the tooth's marginal ridge and interdental space in the case of internal/external infiltration of proximal caries.


Assuntos
Colagem Dentária , Esmalte Dentário , Dentina , Etanol , Humanos , Etanol/química , Colagem Dentária/métodos , Adesivos Dentinários/química , Dente Serotino , Cimentos de Resina/química , Restauração Dentária Permanente/métodos , Microscopia Confocal , Resinas Sintéticas/química , Cárie Dentária/terapia , Microscopia Eletrônica de Varredura , Resinas Compostas/química
18.
Arch Oral Biol ; 164: 105978, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38718465

RESUMO

OBJECTIVE: To evaluate the effect of the association of potassium iodide to antimicrobial photodynamic therapy on human carious dentin produced with a microcosm biofilm model. METHODS: A microcosm biofilm model was used to generate a caries lesion on human dentin. Pooled human saliva diluted with glycerol was used as an inoculum on specimens immersed on McBain artificial saliva enriched with 1 % sucrose (24 h at 37 °C in 5 % CO2). After refreshing culture media for 7 days, the dentin specimens were divided in 5 groups (3 specimens per group, in triplicate; n = 9): C (NaCl 0.9 %), CX (2 % chlorhexidine), PKI (0.01 % methylene blue photosensitizer+50 mM KI), L (laser at 15 J, 180 s, 22.7 J/cm2), and PKIL (methylene blue + KI + Laser). After the treatments, dentin was collected, and a 10-fold serial dilution was performed. The number of total microorganisms, total lactobacilli, total streptococci, and Streptococcus mutans was analyzed by microbial counts (CFU/mL). After normality and homoscedasticity analysis, the Welch's ANOVA and Dunnett's tests were used for CFU. All tests used a 5 % significance level. RESULTS: CX and PKIL groups showed significant bacterial decontamination of dentin, compared to group C (p < 0.05) reaching reductions up to 3.8 log10 for CX for all microorganisms' groups and PKIL showed 0.93, 1.30, 1.45, and 1.22 log10 for total microorganisms, total lactobacilli, total streptococci, and S. mutans, respectively. CONCLUSION: aPDT mediated by the association of KI and methylene blue with red laser reduced the viability of microorganisms from carious dentin and could be a promising option for cavity decontamination.


Assuntos
Biofilmes , Cárie Dentária , Dentina , Azul de Metileno , Fotoquimioterapia , Fármacos Fotossensibilizantes , Iodeto de Potássio , Streptococcus mutans , Humanos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Fotoquimioterapia/métodos , Cárie Dentária/microbiologia , Cárie Dentária/tratamento farmacológico , Cárie Dentária/terapia , Dentina/microbiologia , Dentina/efeitos dos fármacos , Iodeto de Potássio/farmacologia , Iodeto de Potássio/uso terapêutico , Biofilmes/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Saliva/microbiologia , Lactobacillus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos , Clorexidina/farmacologia , Clorexidina/uso terapêutico , Técnicas In Vitro , Contagem de Colônia Microbiana , Saliva Artificial , Lasers
19.
Biomed Mater ; 19(4)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38756029

RESUMO

Hard tissue engineering scaffolds especially 3D printed scaffolds were considered an excellent strategy for craniomaxillofacial hard tissue regeneration, involving crania and facial bones and teeth. Porcine treated dentin matrix (pTDM) as xenogeneic extracellular matrix has the potential to promote the stem cell differentiation and mineralization as it contains plenty of bioactive factors similar with human-derived dentin tissue. However, its application might be impeded by the foreign body response induced by the damage-associated molecular patterns of pTDM, which would cause strong inflammation and hinder the regeneration. Ceria nanoparticles (CNPs) show a great promise at protecting tissue from oxidative stress and influence the macrophages polarization. Using 3D-bioprinting technology, we fabricated a xenogeneic hard tissue scaffold based on pTDM xenogeneic TDM-polycaprolactone (xTDM/PCL) and we modified the scaffolds by CNPs (xTDM/PCL/CNPs). Through series ofin vitroverification, we found xTDM/PCL/CNPs scaffolds held promise at up-regulating the expression of osteogenesis and odontogenesis related genes including collagen type 1, Runt-related transcription factor 2 (RUNX2), bone morphogenetic protein-2, osteoprotegerin, alkaline phosphatase (ALP) and DMP1 and inducing macrophages to polarize to M2 phenotype. Regeneration of bone tissues was further evaluated in rats by conducting the models of mandibular and skull bone defects. Thein vivoevaluation showed that xTDM/PCL/CNPs scaffolds could promote the bone tissue regeneration by up-regulating the expression of osteogenic genes involving ALP, RUNX2 and bone sialoprotein 2 and macrophage polarization into M2. Regeneration of teeth evaluated on beagles demonstrated that xTDM/PCL/CNPs scaffolds expedited the calcification inside the scaffolds and helped form periodontal ligament-like tissues surrounding the scaffolds.


Assuntos
Cério , Matriz Extracelular , Nanopartículas , Osteogênese , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Animais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Suínos , Matriz Extracelular/metabolismo , Cério/química , Nanopartículas/química , Ratos , Poliésteres/química , Dentina/química , Humanos , Regeneração Óssea/efeitos dos fármacos , Odontogênese , Diferenciação Celular , Regeneração , Macrófagos/metabolismo , Crânio , Ratos Sprague-Dawley
20.
Braz Oral Res ; 38: e034, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747821

RESUMO

The aim of this study was to investigate the effect of acid challenge on the activation of matrix metalloproteinases (MMPs) in the Dentinoenamel junction of primary and permanent teeth submitted to radiotherapy. For this purpose, a total of 178 dental fragments obtained from molars were used, and randomly divided into 2 groups (primary and permanent teeth) / 4 experimental subgroups (irradiated and non-irradiated, demineralized and non-demineralized). The fragments were exposed to radiation, with a dose fraction of 2 Gy, for 5 consecutive days, until a total dose of 60 Gy was reached, with a total of 30 cycles, for 6 weeks. To determine the activity of MMPs on the dentinoenamel junction (DEJ), in situ zymography assays on 0.6mm dental fragments were performed. To assess whether MMP activity would be impacted by an acidic environment, the fragments were placed in a demineralizing solution (pH of 4.8). The finding was that irradiation activated MMPs in DEJ and these effects were more evident in permanent when compared with primary teeth. When the effect of an acid challenge on MMPs activity was investigated, demineralization was observed not to increase MMPs activity in non-irradiated teeth, but it did increase MMPs activity in irradiated teeth. In conclusion, an acid challenge was found to exacerbate activation of MMPs in DEJ of permanent teeth submitted to irradiation, but not in primary teeth.


Assuntos
Metaloproteinases da Matriz , Metaloproteinases da Matriz/metabolismo , Metaloproteinases da Matriz/efeitos da radiação , Metaloproteinases da Matriz/análise , Humanos , Fatores de Tempo , Dente Decíduo/efeitos da radiação , Dente Decíduo/efeitos dos fármacos , Dentina/efeitos da radiação , Dentina/efeitos dos fármacos , Dentina/enzimologia , Dentição Permanente , Distribuição Aleatória , Concentração de Íons de Hidrogênio , Desmineralização do Dente , Estatísticas não Paramétricas , Análise de Variância , Valores de Referência , Ativação Enzimática/efeitos da radiação , Ativação Enzimática/efeitos dos fármacos
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