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1.
Cureus ; 16(3): e55964, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38601383

RESUMO

Background Glass ionomer cement (GIC) is widely recognized for its self-adhesive characteristics and biocompatibility, making it commonly used as a restorative material. However, challenges related to limited antibacterial effectiveness and relatively low mechanical properties have hindered its widespread clinical use. Clove and ginger are recognized for their potent antimicrobial activity against numerous pathogenic microorganisms. The present study aims to enhance the clinical applicability of GIC by modifying it with clove and ginger extract. Aim The objective of the study is to assess the antimicrobial effectiveness and compressive strength of GIC modified with ginger and clove extract. Materials and methods Ginger and clove extracts were prepared and incorporated into conventional GIC at three concentrations for each, creating ginger-modified GIC groups (Group A, Group B, and Group C) and clove-modified GIC groups (Group D, Group E, and Group F), with Group G as the control (conventional GIC without modification). The antimicrobial assessment was conducted on disc-shaped GIC specimens (3.0 mm height x 6.0 mm diameter) prepared using molds. Bacterial strains were used to evaluate antimicrobial properties, with minimum inhibitory concentration (MIC) assays conducted at intervals of one to four hours for both modified and unmodified groups. Compressive strength specimens were prepared using cylindrical molds (6.0 mm height × 4.0 mm diameter), according to the ISO (International Organization for Standardization) guidelines. The evaluation was conducted using a Zwick universal testing machine (ElectroPuls® E3000, Instron, Bangalore, India), with the highest force at the point of specimen fracture recorded to determine compressive strength. Statistical analysis was conducted utilizing a one-way analysis of variance (ANOVA) alongside Tukey's post hoc test, with a significance threshold set at p < 0.01. Results The antimicrobial effectiveness of clove and ginger-modified GIC was assessed through a MIC assay, revealing a statistically significant improvement in antimicrobial potency against Streptococcus mutans and Lactobacillus within the modified groups compared to the control group (p < 0.01). Increased extract concentration correlated with enhanced antimicrobial activity. Clove-modified GIC exhibited superior antimicrobial efficacy compared to ginger extract. Compressive strength was higher in clove-modified GIC groups (p < 0.01), with Group F showing a maximum value of 175.88 MPa, while other modified groups demonstrated similar results to the control, with a value of 166.81 MPa (p > 0.01). Conclusion The study concludes that both clove-modified GIC and ginger-modified GIC exhibited antimicrobial activity against Streptococcus mutans and Lactobacillus species. The antimicrobial activity was notably higher in clove-modified GIC compared to ginger-modified GIC. Additionally, the compressive strength of clove-modified GIC surpassed all other groups. Thus, clove-modified GIC emerges as a promising restorative material for addressing recurrent caries. Future investigation is necessary to assess the long-term durability of the material.

2.
Cureus ; 16(3): e56078, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618398

RESUMO

Background and objective Glass ionomer cement (GIC), also known as polyalkenoate cement, has been extensively used in dentistry for both luting and restorative purposes. Despite being the first choice for aesthetic restorations due to their chemical bonding ability to teeth, GICs have faced challenges such as low mechanical properties, abrasion resistance, and sensitivity to moisture, leading to the search for improved materials.  This study aims to assess the effects of thermocycling on the compressive, flexural strength, and microhardness of green-mediated nanocomposite-modified GIC in comparison to traditional GIC. Methodology Green-mediated nanoparticles, consisting of chitosan, titanium, zirconia, and hydroxyapatite (Ch-Ti-Zr-HA), were synthesized using a one-pot synthesis technique to form nanocomposites. These nanocomposites were then incorporated into GIC specimens in varying concentrations (3%, 5%, and 10%), denoted as Group I, Group II, and Group III, respectively. Group IV served as the control, consisting of conventional GIC. To assess the performance of the novel restorative materials over an extended period, compressive strength, flexural strength, and microhardness were measured before and after thermocycling using a universal material testing machine. Furthermore, scanning electron microscopy (SEM) analysis was carried out following the thermocycling process. The collected data were subjected to statistical analysis through one-way analysis of variance (ANOVA) and paired t-tests. Results  The findings demonstrated that, in comparison to the control group, both the mean compressive strength and flexural strength, as well as hardness, were notably higher for the 10% and 5% nanocomposite-modified GIC specimens before and after thermocycling (P < 0.05). Notably, there was no notable difference observed between the 5% and 10% concentrations (P > 0.05). These results suggest that incorporating green-mediated nanocomposites (Ch-Ti-Zr-HA) modified GIC at either 5% or 10% concentration levels leads to improved mechanical properties, indicating their potential as promising alternatives in dental restorative materials. Conclusions Based on our findings, it can be inferred that the 10% and 5% concentrations of green-mediated (Ch-Ti-Zr-HA) modified GIC exhibit superior compressive and flexural strength compared to conventional GIC. Additionally, analysis of the scanning electron microscope (SEM) morphology revealed that green-mediated GIC displays smoother surface characteristics in contrast to conventional GIC. These results underscore the potential advantages of utilizing green-mediated nanocomposite-modified GIC in dental applications, suggesting enhanced mechanical properties and surface quality over conventional.

3.
Cureus ; 16(3): e56234, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618412

RESUMO

Background Glass ionomer cement (GIC) demonstrates biocompatibility and fluoride ion release, indicating their potential to inhibit a wide range of bacteria, although this remains uncertain. Lemongrass and neem are recognized for their potent antimicrobial activity against numerous pathogenic microorganisms. The objective of the study is to evaluate the antimicrobial effectiveness and compressive strength of GIC modified with neem and lemongrass. Methodology Lemongrass and neem were incorporated into conventional GIC at varying concentrations. Group I - neem-modified GIC (0.5%, 1%, 2%), group II - lemongrass-modified GIC (0.5%, 1%, 2%), and group III (non-modified GIC as a control group). The disk-shaped specimens were then compared to unmodified GIC (control). Antimicrobial effectiveness was assessed using the minimal inhibitory concentration (MIC) assay against Streptococcus mutans and Lactobacillus. Compressive strength was assessed using a Universal Testing Machine, with a crosshead speed set to 0.5 mm per minute. Statistical analysis was conducted with a significance level set at p < 0.05. Results Neem modification displayed superior antimicrobial effectiveness against both Streptococcus mutans and Lactobacillus at all concentrations when compared to the control, with 2% showing the least mean value of 0.262. In contrast, lemongrass modification exhibited a significant difference in effectiveness against Streptococcus mutans but no difference against Lactobacillus. Neem modification demonstrated superior performance compared to lemongrass (p < 0.05). Both modified groups showed no significant impact on compressive strength. Conclusions Neem-modified GIC demonstrated the highest antimicrobial efficacy against Streptococcus mutans and Lactobacillus without altering its compressive strength. This suggests its potential as a promising alternative material in restorative dentistry. Additional in vivo investigations are needed to assess the extended-term effectiveness of the material.

4.
Cureus ; 16(2): e54517, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38516425

RESUMO

Background Discoloration affects glass ionomer cement (GIC) color stability due to its brittle nature and microporosity. To counter this, incorporating alternative materials is essential for maintaining color stability. Aim This study aims to determine the color stability and gloss of GIC modified with bioactive chitosan, titanium, zirconia, and hydroxyapatite nanoparticles before and after artificial aging. Materials and methods  The study was conducted at Saveetha Research Centre, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, located in Chennai, India. Green-mediated chitosan, titanium, zirconia, and hydroxyapatite (Ch-Ti-Zr-HA) nanoparticles were synthesized using the one-pot synthesis technique. Forty-eight disc-shaped specimens were prepared by incorporating the obtained nanoparticles (nanocomposite) into the GIC, with a diameter of 5 mm and thickness of 2 mm. The specimens were prepared in different concentrations (3%, 5%, and 10%) designated as group I, group II, and group III, respectively. Group IV, serving as the control, consisted of conventional GIC without any modifications. Following preparation, scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) microanalysis confirmed sample elements, and the specimens were submerged in distilled water for a duration of 24 hours prior to the commencement of testing. Subsequently, the specimens underwent artificial aging (thermocycling), between temperatures of 5°C and 55°C, for a total of 30,000 cycles, with a 30-second dwell time. Color change and gloss characteristics were assessed both after 24 hours and following thermocycling using a spectrophotometer and glossometer, respectively. The average color change parameter (ΔE) was measured using Adobe Photoshop. The data obtained were subjected to statistical analysis using an unpaired t-test. Results Significant color stability variations were observed post thermocycling (P = 0.001). Group 2 (5%) exhibited minimal delta E difference (0.508 ± 0.105), indicating superior color stability, while group 4 (control) had maximum difference (1.15 ± 0.187), indicating lower stability. Gloss tests confirmed GIC's polishability, where there were significant differences among all the groups. Conclusion It can be concluded that 5% nanoparticle-modified GIC has better color stability and gloss than conventional GIC. Further studies are needed to analyze the color stability and gloss through dentifrices and other beverages.

5.
Cureus ; 16(2): e54821, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38529417

RESUMO

Background According to existing literature, introducing natural antibacterial agents into glass ionomer cement (GIC) has been associated with potential negative impacts on their strength properties. Hence, this study aims to explore the antibacterial effectiveness of glass ionomer cement enriched with Acacia nilotica and subsequently assess its compressive strength characteristics. Aim The objective of the study is to assess the antimicrobial effectiveness and compressive strength of glass ionomer cement modified with Acacia nilotica. Materials and methods  The plant extract was incorporated into the conventional glass ionomer cement in three different proportions (powder GIC: extract: liquid GIC), divided into group I, group II, and group III with ratios of 2:1:1, 3:1:2, and 3:2:1 respectively. Additionally, a control group denoted as group IV was included without any modifications. Subsequently, the specimens were prepared, and their chemical structure was analyzed using Fourier transform infrared spectroscopy (FTIR), followed by testing for antimicrobial activity using the minimum inhibitory concentration (MIC) assay against Streptococcus mutans and Lactobacillus. The assessment of compressive strength was conducted following ISO 9917-1:2007 standards, and the recorded values represent the maximum force the specimen could withstand before fracturing. Results The antimicrobial effectiveness against Streptococcus mutans and Lactobacillus exhibited a notable increase in all modified specimens compared to the control group, with a significance level of p<0.05. Additionally, significant improvements in compressive strength were observed in group III (183.49±2.99) when compared to the remaining groups. The higher concentrations of the plant extract resulted in superior outcomes. Conclusion Therefore, the incorporation of Acacia nilotica into GIC shows promising potential as a restorative material. These investigations can provide valuable insights into the material's performance and durability, contributing to its potential application in dental restorations. Future research is needed to thoroughly investigate the bonding chemistry between Acacia nilotica and GIC, as well as to assess the extent of microleakage.

6.
J Long Term Eff Med Implants ; 34(3): 43-53, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505893

RESUMO

The aim of this systematic review was to identify and analyze the findings of various studies that analyzed the changes in the color stability of maxillofacial prosthetic materials after the addition of various colorants and nanoparticles and assess the change in color after being subjected to either natural or artificial accelerated aging as well as outdoor aging. This systematic review was conducted in accordance with the guidelines of transparent reporting of systematic reviews and meta-analysis (PRISMA Statement). The primary objective of this systematic review was to evaluate the color stability of maxillofacial prosthesis. The secondary objective was to assess the effect of various colorants; pigments; opacifiers; UV absorbers-such as inorganic colorants (dry earth pigments); metal oxides; and organic colorants. The time period of the included studies extended from 2013 to 2023. Electronic database search identified a total of 217 studies. Ten studies were included to meet the research question. All 10 included studies analyzed the effect of various colorants and their exposure to various aging and weathering conditions. It was found that various pigments and nanoparticles had an effect on the color stability. Also weathering and aging conditions had a direct effect on the color stability as well. In terms of disinfection, although there was not much color difference observed, highest change in color stability was observed when rubbing or brushing of the prosthesis was carried out. In conclusion, the color stability of maxillofacial prosthetics is a critical factor that influences both patient satisfaction and the overall cosmetic look. The potential of pigments and nanoparticles to enhance the color stability of silicone-based maxillofacial prosthesis has received much research. By avoiding color fading and discoloration brought on by environmental variables including UV radiation, aging, and chemical exposure, the inclusion of various pigments and nanoparticles has been demonstrated to improve the color stability of silicone maxillofacial prostheses.


Assuntos
Prótese Maxilofacial , Pigmentação em Prótese , Humanos , Elastômeros de Silicone , Cor , Próteses e Implantes , Teste de Materiais
7.
Cureus ; 16(2): e53484, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38440002

RESUMO

BACKGROUND: Glass ionomer cement (GIC) restorations are commonly used in primary dentition, due to their aesthetic appeal, self-adhesive nature, and biocompatibility. However, the material's limited antibacterial activity and inadequate mechanical strength highlight the necessity for modifying the material. AIM: The study aims to evaluate and compare the antimicrobial potency and compressive strength of GIC-incorporated Miswak extract with that of conventional GIC. MATERIALS AND METHODS: After obtaining the Miswak extract, a modified GIC was formulated by combining the extract with the conventional GIC powder and liquid components, in three different ratios (Powder: Extract and Liquid), Group I (2:1:1), Group II (3:1:2), Group III (3:2:1), and the Group IV as control, which consist of unmodified/conventional GIC. To evaluate and compare the antibacterial efficacy of the modified and unmodified GIC, standard strains of Streptococcus mutans and Lactobacillus were utilized. For each group, the minimal inhibitory concentration (MIC) assay was tested. For the evaluation of compressive strength, cylindrical moulds were utilized in compliance with ISO 9917-1:2007 standards and tested using the universal testing machine (Instron, ElectroPuls®, Bangalore, IND). The highest force exerted at the point of specimen fracture was recorded to calculate the compressive strength values in MPa. The data obtained were analyzed using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 24.0, Armonk, NY) software. The statistical analysis was conducted utilizing repeated measures of analysis of variance (ANOVA) to calculate the mean MIC values and compressive strength, with pairwise comparisons assessed using Tukey's post hoc test. RESULTS: The results proved that the antimicrobial properties of Miswak containing GIC performed better against S. mutans and Lactobacillus with a statistically significant difference when compared with group IV (p<0.05), it has been found that an increase in the concentration of extract increased the antimicrobial potency. Significant results were obtained in compressive strength where Group II (41.49±3.6) and Group III (15.23±4.96) proved to be weaker than the control (62.69±2.58), while Group I showed no differences from the control group (p>0.05). CONCLUSION: It can be concluded that Group I was found to be better in terms of both antimicrobial properties and compressive strength, where no significant difference in compressive strength was identified when comparing Group I with Group IV. Thus, the overall study depicts that a lesser concentration of extract can be the best option in terms of good antimicrobial properties without altering its strength. Hence, the Miswak containing GIC could be a promising restorative material; further studies should include considering intraoral variables such as masticatory stress, moisture levels and in-vivo tests of this combination.

8.
Cureus ; 16(1): e52198, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38347981

RESUMO

BACKGROUND: Glass ionomer cements are commonly utilized in dental restorations due to their biocompatibility, strong chemical bond with dental tissues, and ability to resist tooth decay. However, their effectiveness can be compromised by the presence of persistent cavity-causing microorganisms. Therefore, it is essential to consider incorporating antibacterial agents into these restorative materials. Swertia chirayita (S. chirayita) and Terminalia arjuna (T. arjuna) are well-known for their rich composition of phytochemicals that can potentially inhibit the growth of bacteria. Hence, the current research is focused on modifying glass ionomer cement with Chirayita and T. arjuna extracts to enhance its antibacterial properties. AIM: This research aims to determine the antimicrobial efficacy and compressive strength of glass ionomer cement modified with Chirayita and T. arjuna extracts. METHODOLOGY: Plant extracts were prepared from both Chirayita and T. arjuna. The powder and liquid components of conventional glass ionomer cement (GIC) were mixed, followed by adding these extracts at three different concentrations. To assess antimicrobial properties, typical strains of Streptococcus mutans and Lactobacillus were employed to test both the modified GIC and unmodified GIC (used as a control). For Chirayita and T. arjuna-modified GIC, minimum inhibitory concentration (MIC) assays were conducted at three different concentrations. MIC was assessed at various time intervals ranging from 1 to 4 hours for modified and unmodified groups. Moreover, compressive strength was measured using cylindrical molds. The highest force exerted at the point of specimen fracture was recorded to calculate the compressive strength values in megapascal (MPa). RESULTS: The antimicrobial efficiency of Chirata and T. arjuna-modified GIC was evaluated using a MIC assay, indicating a statistically significant enhancement in antimicrobial potency against S. mutans and Lactobacillus within the modified groups in contrast to the control group (p<0.05). However, there were no notable changes in compressive strength when comparing the control group to the modified groups (p>0.05). CONCLUSION: The antimicrobial effectiveness against S. mutans was observed to be greater in both T. arjuna and Chirayita-modified GIC. In the case of Lactobacillus, Chirayita-modified GIC exhibited more pronounced antimicrobial properties compared to T. arjuna. Importantly, both extracts did not alter the compressive strength of Conventional (unmodified) GIC. Hence, Chirayita-modified GIC appears to be a promising restorative material for combatting recurrent caries. Additional investigation is required to assess the material's stability over an extended period.

9.
Cureus ; 16(1): e52160, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38344646

RESUMO

Background Photobiomodulation techniques, particularly low-level laser therapy (LLLT), have gained traction due to their ability to accelerate osseointegration by stimulating cellular metabolism and promoting tissue healing. This study explores the effectiveness of LLLT around dental implants at various intervals after placement. Using resonance frequency analysis (RFA), the implant stability quotient (ISQ) was measured to assess implant stability. Methodology This split-mouth, randomized, single-blinded clinical trial included 20 participants undergoing dental implant placement. The test group received LLLT while the control group had no laser treatment. Implant stability was assessed using RFA at one, two, four, and twelve weeks post-implant placement. Statistical analysis involved descriptive statistics, repeated-measures analysis of variance (ANOVA), and t-tests. Results The repeated-measures ANOVA analysis showed significant differences in the ISQ values between the LLLT group and the control group at two weeks and three months post-implant placement. The LLLT group exhibited higher ISQ values, indicating greater implant stability and improved osseointegration compared to the control group. These findings suggest the potential benefits of LLLT in enhancing dental implant outcomes. Conclusions LLLT shows promise in improving dental implant outcomes, with enhanced stability and osseointegration. Further research is needed to validate these results and integrate LLLT into routine dental implant procedures.

10.
J Indian Prosthodont Soc ; 24(1): 46-51, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38263557

RESUMO

AIM: The conventional technique of implant uncovery using a blade and scalpel is associated with various drawbacks, including profuse bleeding, soft-tissue trauma, delayed healing, and patient noncompliance. Therefore, there is a need to explore the alternative approaches that offer improved accuracy and time efficiency during the cover screw location at the second stage of recovery. This study aims to assess the accuracy and time efficiency of a novel technique that utilizes an apex locator in comparison to conventional locating techniques for implant uncovery. SETTINGS AND DESIGN: The study employed a simple randomized controlled trial with a sample size of 161. MATERIALS AND METHODS: The study employed apex locator (Woodpecker Woodpex III Gold 5th generation) in conjunction with a K-file (Mani k-file #10, 21 mm) for detecting the implant location. The accuracy of the novel technique was determined based on the values measured on the apex locator, with positive values indicating soft-tissue response and negative values indicating the cover screw (metal). The accuracy was cross-verified using radiovisiography (RVG). The clinician-based scoring was also done, considering RVG evaluation, amount of incision given, and ease of the procedure. The time required to locate the cover screw was recorded using a timer for both the novel technique and the conventional method. STATISTICAL ANALYSIS USED: All the recorded values were statistically analyzed using the independent t-test (P < 0.005) with the SPSS software (version 23). RESULTS: The results revealed a significant difference in terms of incision given, ease of treatment, and time taken for the procedure (P < 0.05), while the accuracy of the novel technique was not disturbed (P > 0.05). CONCLUSION: Based on the findings of this in vivo study, the use of an apex locator as an alternative to conventional methods for detecting cover screw location at the second stage of recovery is recommended. The novel technique demonstrated faster uncovering of implants without posing any risks to the surrounding tissues or implants.


Assuntos
Ferida Cirúrgica , Humanos , Parafusos Ósseos , Cooperação do Paciente
11.
J Indian Prosthodont Soc ; 24(1): 82-87, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38263562

RESUMO

AIM: The aim of this study was to analyze and compare the stress distribution on dental implants in various positions when used with implant-assisted removable partial dentures. SETTINGS AND DESIGN: This was an in vitro study. MATERIALS AND METHODS: A model representing a mandibular bilateral partially edentulous condition, with missing premolars and molars, was fabricated using epoxy resin. Two implants of similar diameter measuring 4.0 mm × 10 mm (Dentium, Korea) were inserted in the second molar and the second premolar region on either side of the model for comparing the biomechanical effect of various implant locations. Two types of loads 100N and 125N were applied vertically using universal testing machines in the premolar and molar regions. The loads on the implants beneath the cast partial denture were measured by physical stress analysis using a microstrain gauge. STATISTICAL ANALYSIS USED: A comparison of maximum stress observed at the premolar versus molar regions due to the application of the 100N and 125N loads was done using the Mann-Whitney U-test. RESULTS: In physical stress analysis, obtained results were statistically analyzed, and the result was statistically not significant (P = 0.435 at 100N and P = 0.718 at 125N) in positional changes of implant. CONCLUSION: In the current study, the statistical analysis of physical stress revealed no significant differences in stress values between the loadings at the premolar and molar regions. This suggests that the implant can be placed in either the premolar or molar region based on the availability of bone without affecting stress distribution.


Assuntos
Implantes Dentários , Prótese Parcial Removível , Prótese Parcial , Resinas Epóxi , Mandíbula
12.
Chem Phys Lipids ; 259: 105374, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38176612

RESUMO

Soluble alpha-amylases play an important role in the catabolism of polysaccharides. In this work, we show that the malt α -amylase can interact with the lipid membrane and further alter its mechanical properties. Vesicle fluctuation spectroscopy is used for quantitative measurement of the membrane bending rigidity of phosphatidylcholines lipid vesicles from the shape fluctuation based on the whole contour of Giant Unilamellar Vesicles (GUVs). The bending rigidity of the 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine lipid vesicles in water increases significantly with the presence of 0.14 micromolar alpha-amylase (AA) in the exterior solution. It appears that the enzyme present in the external solution interacts with the outer layer of the bilayer membrane, leading to an asymmetry of the solution on either side of the bilayer membrane and altering its elasticity. At AA concentration of 1.5 micromolars and above, changes in the morphology of the GUV membrane are observed. The interaction between AA in the external solution and the external leaflet causes the bilayer membrane to curve spontaneously, leading to the formation of outbuds, giving a positive spontaneous curvature of C0 ≤ 0.05 µm-1 at ≈ 1 mg / ml of the AA concentration. We validate and characterize its concentration-dependent role in stabilizing the membrane curvature. Our findings indicate that the involvement of the enzyme, depending on the concentration, can have a considerable effect on the mechanical characteristics of the membrane.


Assuntos
Bicamadas Lipídicas , alfa-Amilases , Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Lipossomas Unilamelares/química
13.
J Phys Chem B ; 127(49): 10508-10517, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38052045

RESUMO

Temporal regulation between input and output signals is one of the hallmarks of complex biological processes. Herein, we report that the conformational disposition of a protein in macromolecularly crowded media can be controlled with time using enzymes. First, we demonstrate the pH dependence of bovine serum albumin (BSA) condensation and conformational alteration in the presence of poly(ethylene glycol) as a crowder. However, by exploiting the strength of pH-modulatory enzymatic reactions (glucose oxidase and urease), the conversion time between the condensed and free forms can be tuned. Additionally, we demonstrate that the trapping of intermediate states with respect to the overall system at a particular α-helix or ß-sheet composition and rotational mobility can be possible simply by altering the substrate concentration. Finally, we show that the intrinsic catalytic ability of BSA toward the Kemp elimination (KE) reaction is inhibited in the aggregated form but regained in the free form. In fact, the rate of KE reaction can also be actuated enzymatically in a temporal fashion, therefore demonstrating the programmability of a cascade of biochemical events in crowded media.


Assuntos
Polietilenoglicóis , Soroalbumina Bovina , Soroalbumina Bovina/química , Substâncias Macromoleculares , Conformação Molecular , Polietilenoglicóis/química , Glucose Oxidase/metabolismo
14.
J Indian Prosthodont Soc ; 23(3): 234-243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929362

RESUMO

Aim: The intraoral scanners are digital devices used to digitise the oral tissues. The accuracy of the intraoral scanners has been studied under different environmental conditions, but there might be differences that occur in the actual oral environment, which is still in question. The aim of the study was to evaluate the accuracy and efficiency of Parallel Confocal Microscopy and 3D in motion video with triangulation technology-based intraoral scanners under the influence of moisture and mouth opening. Settings and Design: This was an Cross over clinical controlled study. Materials and Methods: The controlled in vivo study included healthy subjects who were in need of CBCT for the purpose of locating the position of unerupted third molars before going abroad for a job. The subjects were exposed to scans in the upper and lower jaws with two intraoral scanners based on 3D motion video technology with triangulation (Medit) and parallel confocal microscopy (Trios) under the influence of two oral conditions, which were moisture (presence and absence of moisture) and mouth opening (30 mm and 50 mm, respectively). A total of 96 scans were obtained and superimposed individually over the reference CBCT scans to find the deviations in the Geomagic Rapidform (version 2020, USA) software. The efficiency of the scanners was calculated by recording the time taken and the number of images obtained after each scan. Statistical Analysis Used: The significance was calculated by using the independent and paired sample t test in SPSS software (IBM, version 23). Results: Based on the surface analysis, the trueness of the intra-oral scanners had statistically significant differences when compared between 3D in motion video technology with Triangulation and Parallel Confocal Microscopy (P < 0.05) whereas no statistical significance was observed in precision. There was a significant difference observed in the efficiency of the intra-oral scanners (P < 0.05). Conclusion: There is a significant difference in the accuracy and efficiency of the intraoral scanners under the influence of oral conditions, such as different moisture levels and mouth opening conditions. 3D in motion video technology with Triangulation showed better results with the least deviation than Parallel Confocal Microscopy.


Assuntos
Técnica de Moldagem Odontológica , Imageamento Tridimensional , Humanos , Desenho Assistido por Computador , Microscopia Confocal , Tecnologia , Estudos Cross-Over
15.
J Indian Prosthodont Soc ; 23(4): 391-397, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37861617

RESUMO

Aim: This study investigates the effectiveness of an innovative virtual tooth preparation workflow for the fabrication of dental crowns using cone-beam computed tomography (CBCT) and intraoral scanners (IOSs) with conventional workflow using extraoral/laboratory scanners. Settings and Design: This in vitro experimental study was conducted in the laboratory of a university in Chennai, India. The dental laboratory and research facilities at the institution were utilized for the fabrication of the temporary crowns and the data acquisition process. Materials and Methods: Institutional approval was obtained from the university. It was basically a comparison between the virtual prep technique using CBCT and IOS and the conventional digital technique using extra oral scanners (EOS) for temporary crown fabrication. The sample size was estimated using an effect size of 1.5004, assuming a normal distribution, a significance level of 0.05, and a power of 0.95 in G power software. Based on this calculation, an extracted second lower molar was used to fabricate 10 samples in each group. The samples were divided into three groups: the CBCT (Group 1), the IOS (Group 2), and laboratory scanner (Group 3 as control) groups. The vertical marginal gap of all the surfaces of the crown was evaluated using a scanning electron microscope. Statistical Analysis Used: Data were analyzed using one-way ANOVA using the SPSS software version 26.0, IBM, Armonk, NY, USA. Results: Acceptable marginal discrepancy values were obtained in all three groups. There was no significant difference in the marginal discrepancy recorded (P = 0.113). Conclusion: Virtual tooth preparation using CBCT and IOSs can be used as an alternative to the conventional workflow for provisional crown and bridge fabrication.


Assuntos
Desenho Assistido por Computador , Coroas , Humanos , Fluxo de Trabalho , Planejamento de Prótese Dentária/métodos , Adaptação Marginal Dentária , Índia
16.
J Mater Chem B ; 11(43): 10383-10394, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37874292

RESUMO

Gaining control over the stability and cleavage of phosphoester and phosphodiester remains a matter of interest for their application in biotechnology to oligonucleotide-based therapeutics. Herein, we report an efficient unactivated phosphoester hydrolysis (stable mono/di/tri/cyclic nucleotide to nucleoside conversion) via a biosupramolecular system comprising of a non-covalent complex of enzyme, alkaline phosphatase (ALP), and Zn(II)-metallosurfactant. We also demonstrate the nucleobase selective activation or inhibition of ALP-mediated oligonucleotide digestion process using that complex. The higher binding affinity of Zn(II)-containing headgroup with phosphate-containing substrate enhanced the effective substrate concentration surrounding the enzyme, which, in turn, results in a drastic decrease in the Michaelis constant (KM), along with an increase in the turnover (kcat). The catalytic activation or inhibition of nucleobase-specific oligonucleotide digestion depends on the hydration, localization of the substrates, and viscosity of the resultant co-assembly upon substrate binding with the enzyme-metallosurfactant complex. Additionally, through isothermal titration calorimetry experiment, we demonstrate enthalpy-entropy change during both the supramolecular binding of (oligo)nucleotides and simultaneous activation/inhibition in catalytic cleavage. Overall, it showed the possible modularity of Zn(II)-mediated biosupramolecular interaction, describing intrinsic thermodynamic aspects in developing complex biocatalytic circuits with nucleobase-specific oligonucleotides inputs, which are relevant in designing nucleic acid-based cargo for drug delivery and bioimaging.


Assuntos
Fosfatase Alcalina , Nucleotídeos , Termodinâmica , Hidrólise , Oligonucleotídeos/química , Catálise
17.
Dent Res J (Isfahan) ; 20: 96, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810450

RESUMO

Background: Carnitine is effective in preventing the accumulation of end products related to lipid peroxidation due to its anti-inflammatory and antioxidant effects. Carnitine also exerts a significant anti-inflammatory role through the downregulation of the nuclear factor kappa beta pathway, which leads to a decrease in the expression of pro-inflammatory cytokines.The aim of the study was to estimate the L-carnitine (L-C) levels in diabetic completely edentulous patients. Materials and Methods: A cross-sectional study was conducted after the selection of 60 samples based on the inclusion and exclusion criteria. The collected saliva samples were utilized to measure the levels of L-C using the sandwich enzyme-linked immunosorbent assay (ELISA) method. One hundred microliters of sample was applied to a particular row of wells and incubated for an hour as part of the sandwich ELISA procedure. After the wells had been cleaned, a second batch of monoclonal L-C was added, and they were once more incubated for an hour. The horseradish peroxidase substrate was then applied after washing the second batch as well. To allow the blue-to-yellow color transition, the wells were kept steady. Following the observation of the color shift, the OD was measured, and the concentration was determined using the sandwich ELISA kit's standard curve as an intercept. The data were statistically analyzed using the independent t-test (significant level P < 0.05) and were tabulated. Results: The L-C levels have higher levels in nondiabetic patients than in diabetic patients. The difference in the baseline mean value between the groups was statistically significant (P = 0.00). Although it is statistically significant (P = 0.00), the mean value for diabetic individuals is 0.19 as opposed to 0.29 for nondiabetic patients. Conclusion: Based on the findings, it can be concluded that L-C improves insulin sensitivity and glucose disposal in diabetic completely edentulous patients.

18.
Chem Asian J ; 18(19): e202300657, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37639220

RESUMO

Both micelles and self-assembled monolayer (SAM)-protected nanoparticles are capable of efficiently hosting water-immiscible substrates to carry out organic reactions in aqueous media. Herein, we have analyzed the different catalytic effect of SAM-protected cationic nanoparticles and cationic surfactants of varying chain length towards base-catalyzed proton transfer mediated ring-opening reaction of 5-nitrobenzisoxazole (NBI) (also known as Kemp Elimination (KE) reaction). We use inorganic phosphate ion or different nucleotide (phosphate-ligated different nucleoside) as base to promote the reaction on micellar or nanoparticle interface. We find almost 2-3 orders of magnitude higher concentration of surfactants of comparable hydrophobicity required to reach the similar activity which attained by low cationic head group concentration bound on nanoparticle. Additionally, at low concentration of nanoparticle-bound surfactant or with high surfactant in micellar form, nucleotide-selectivity has been observed in activating KE reaction unlike free surfactant at low concentration. Finally, we showed enzyme-mediated nucleotide hydrolysis to generate phosphate ion which in situ upregulate the KE activity much more in GNP-based system compared to CTAB. Notably, we show a reasonable superiority of SAM-protected nanoparticles in activating chemical reaction in micromolar concentration of headgroup which certainly boost up application of SAM-based nanoparticles not only for selective recognition but also as eco-friendly catalyst.

19.
J Long Term Eff Med Implants ; 33(4): 53-58, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37522585

RESUMO

AIM: The purpose of this retrospective study was to compare, among various implant systems, the influence of primary stability and the bone density and soft tissue biotype of the patient on the amount of peri-implant crestal bone loss after 1 year using radiography. MATERIALS AND METHODS: Included in this retrospective study were patient records of 3583 implant placements utilized from an online dental information archiving software (DIAS). Clinical and radiographic assessments were conducted concurrently with implant placement (baseline) and 1 year post surgery. Statistical analysis was done to examine the mean marginal bone loss significance in the three different implant systems groups (group I: Straumann Roxolid SLAc-tive, group II: Nobel Biocare CC, group III: Straumann SLA), different primary stability values, different bone density. and soft tissue biotype at the time of implant placement. RESULTS: A significant difference was observed in the crestal bone loss with different implant systems used. Group I showed significantly lesser amounts of crestal bone loss when compared to groups II and III. However, the differences in the bone density, ISQ values, and the soft tissue biotype did not exhibit a statistically significant difference in the amount of crestal bone loss. CONCLUSION: Significant MBL preservation for implants with Straumann SLActive when compared to Nobel Biocare CC and Straumann SLA implants. No significant changes were observed with respect to primary stability, bone density, and soft tissue thickness and no correlation among early crestal bone loss and IT, ISQ at surgery, and ISQ at reopening was observed. Straumann Roxolid SLActive implants showed less crestal bone loss probably owing to its hydrophilic surface modification. However, more studies need to be done to evaluate the same.

20.
Chem Commun (Camb) ; 59(43): 6536-6539, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37161733

RESUMO

Herein, we report interactivity and conjugate formation ability between a Zn(II)-metallosurfactant and two clinically relevant serum proteins, albumin (ALB) and γ-globulin (GGB). We found that the surfactant-ALB conjugate promotes coffee ring formation, whereas with GGB it gets suppressed, which is due to the difference in structural anisotropy and hydrophobicity of the conjugates. Additionally, validation of this biosensing platform has been established in human serum samples, and it has potential applications for on-spot rapid diagnostics in remote areas.


Assuntos
Albumina Sérica , gama-Globulinas , Humanos , Albumina Sérica/metabolismo , Proteínas Sanguíneas , Antígenos , Zinco
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