Heat-cured Acrylic Resin Research Articles

Antimicrobial Properties of Aloe vera Ethanol Extract as a Denture Disinfectant: An In Vitro Study.

Introduction The aim of this study was to evaluate the activity of an ethanolic extract of Aloe vera on Candida albicans and Staphylococcus aureus. Materials and methods A total of 42 heat-cured acrylic resin specimens were made and divided into three groups according to the disinfection method: (1) Corega disinfectant tablets; (2) ethanol extract of Aloe vera; and (3) distilled water (as a control group). Fresh Aloe vera whole leaves were washed with distilled water, chopped into small pieces, air-dried, and ground into powder. The powder was extracted with 95% ethanol. The acrylic specimens were contaminated with C. albicans and S. aureus, and then the specimens were immersed in study solutions for three minutes. The viable colonies were counted using the colony-forming units (CFU) method. Results The results showed a decrease in the number of C. albicans CFU for denture tablets and Aloe vera ethanoic extract groups compared to the negative control group. There were no significant statistical differences between the denture tablet group and the Aloe vera ethanolic extract group (P < 0.05). Aloe vera ethanolic extract groups significantly decreased the number of S. aureus CFU compared to the negative control group and less compared to the denture tablet, where significant statistical differences were found between the tablet group and the Aloe vera ethanolic extract group. Conclusions Within the limitations of this study, it was concluded that Aloe vera extract was effective against C. albicans and S. aureus when acrylic resin specimens were immersed for three minutes.

Assessment of Adaptability and Linear Dimensional Changes of Two Heat Cure Denture Base Resin with Different Cooling Techniques: An In Vitro Study.

The current study was designed to assess the linear dimensional changes and adaptability of two heat-cured denture base resins using various cooling methods. To prepare a total of 90 acrylic resin samples (45 acrylic resin samples for each material), four rectangular stainless-steel plates measuring 25 × 25 × 10 mm were fabricated. For both groups, the material was put into the mold at the dough stage. Group I - SR Triplex Hot Heat Cure acrylic; group II - DPI Heat Cure acrylic. Both groups used the same curing procedure. One of the following three techniques was used to cool the material (15 samples from each material) once the curing cycle was finished: (A) water bath, (b) quenching, and (C) air. A traveling microscope was used to measure the distance between the markings on the acrylic samples. The data was recorded and statistically analyzed. In SR Triplex Hot heat cure acrylic material, the maximum linear dimensional changes were found in the quenching technique (0.242 ± 0.05), followed by the air technique (0.168 ± 0.11) and the least was found in the water bath technique (0.146 ± 0.01). In DPI Heat Cure acrylic material, the maximum linear dimensional changes were found in the quenching technique (0.284 ± 0.09), followed by the air technique (0.172 ± 0.18) and the least was found in the water bath technique (0.158 ± 0.10). There was a statistically significant difference found between these three cooling techniques. On comparison of adaptability, the water bath technique, the marginal gap SR Triplex Hot was 0.012 ± 0.02 and DPI Heat Cure was 0.013 ± 0.02. In the quenching technique, the marginal gap SR Triplex Hot was 0.019 ± 0.04 and DPI Heat Cure was 0.016 ± 0.04. In the air technique, the marginal gap SR Triplex Hot was 0.017 ± 0.01 and DPI Heat Cure was 0.019 ± 0.01. The present study concluded that among the different cooling methods, the water bath technique had the least linear dimensional change, followed by the air and quenching techniques. When comparing the materials, DPI Heat Cure acrylic resin showed a greater linear dimensional change than SR Triplex Hot heat cure acrylic resin. During polymerization, heat-cured acrylic resins experience dimensional changes. Shrinkage and expansion are dimensional changes that occur in heat-cured acrylic resins and have an impact on the occlusal relationship and denture fit. However, the denture base's material qualities and the different temperature variations it experiences during production may have an impact on this. How to cite this article: Kannaiyan K, Rathod A, Bhushan P, et al. Assessment of Adaptability and Linear Dimensional Changes of Two Heat Cure Denture Base Resin with Different Cooling Techniques: An In Vitro Study. J Contemp Dent Pract 2024;25(3):241-244.

Influence of Five Different Commercially Available Mouthwashes on the Growth of Candida albicans Adhered to Customized Prefabricated Heat-Cured Denture Base Acrylic Resin Sheets: An In Vitro Study.

Background The purpose of this in vitro investigation was to evaluate the impact of five distinct commercial mouthwashes on the development of Candida albicans that had been adhered to heat-cured acrylic resin sheets. Methods This in vitro investigation was carried out at the MES Medical College's Microbiology Department in Perinthalmanna, Kerala, India. A total of 72 heat-cured acrylic resin sheets, size 10 × 10 × 2 mm, were fabricated. After disinfection, all 72 acrylic sheets were placed in a flask containing a suspension of the standard strain of Candida species (American Type Culture Collection) and incubated at 37ºC for 24 hours. Then, the acrylic sheets were randomly divided into six groups, with each group containing 12 acrylic sheets. Group 1 was the control group to which no mouthwash was added. In group 2, Colgate Plax was added. In group 3, Hiora Himalaya was added. In group 4, Oral B was added. In group 5, Listerine was added. In group 6, Pepsodent was added. Colony-forming units (CFUs) were assessed using a colony counter every six, 24, 48, and 120 hours. After obtaining the pH and CFU of all 72 specimens, software known as the Statistical Package for Social Sciences (SPSS) (IBM Corp., Armonk, NY) was used to analyze the data. Results Candida albicans adhered to heat-cured denture base acrylic resin sheets differed significantly in response to commercially available mouthwashes (Oral B, Colgate Plax, and Pepsodent) and non-commercial mouthwashes (Hiora Himalaya and Listerine) that contained cetylpyridinium chloride. Conclusions Compared to other mouthwashes that do not contain cetylpyridinium chloride (Listerine and Hiora Himalaya), mouthwashes with cetylpyridinium chloride as the active ingredient (Oral B, Pepsodent, and Colgate Plax) have shown good antifungal properties against the adhering Candida albicans on denture base resin.

Toxicity test of mangosteen peel extract (Garcinia mangostana L.) as denture cleanser of heat-cured acrylic resin: in vitro experimental laboratory

ABSTRACTIntroduction: Mangosteen peel extract can be used as a denture cleaning agent to effectively inhibit the growth of C. albicans because mangosteen peel contains various compounds such as mangostin, tannins, flavonoids, saponins. Denture cleaning materials that will be used in the dental field must meet biocompatibility requirements, one of which is a toxicity test. The aim of this study was to analyze the toxicity of mangosteen peel extract as a cleaner of heat cured acrylic resin denture on BHK-21 as cell culture of fibroblast cells. Methods: Toxicity test used the MTT assay method. Acrylic resin samples had a diameter of 3 mm and a thickness of 2 mm. The acrylic resin was soaked for 4 days, equivalent to soaking 15 minutes per day for 1 year in mangosteen peel extract with concentrations of 50, 60, 70%, and sodium hypochlorite. Analyzed data using normality and homogeneity test results showed (p&lt;0.05). Kruskal Wallis test results (0.000&lt;0.05) and Mann Whitney (0.000&lt;0.05). Results: The greatest cell viability value was shown in mangosteen peel extract with a concentration of 50%, namely 97.16939%. Based on research data, it can be said that the lower the concentration of mangosteen peel extract, the lower the level of toxicity of a denture cleanser agent. Mangosteen peel extract in concentrations of 60, 70%, and sodium hypochlorite are toxic when used as a denture cleanser. Conclusion: Mangosteen peel extract with a concentration of 50% is not toxic to BHK-21 fibroblast cells as cell culture of and as a cleaner of heat cured acrylic resin denture on.Keywordheat-cured acrylic resin, mangosteen peel extract, MTT assay.

Effects of Combinations of Hydrogen Peroxide and Vinegar in Different Ratios on the Surface Roughness of Heat-Cure Denture Base Acrylic Resin

Background: Complete dentures are at high risk of contamination, and their disinfection is imperative to prevent cross-contamination. Also, chemical disinfecting agents can effectively eliminate microorganisms. This study aimed to assess the effect of combinations of hydrogen peroxide (HP) and vinegar in different ratios on the surface roughness of heat-cure denture base acrylic resin. Methods: This in vitro, experimental study evaluated 40 heat-cure acrylic resin specimens that were flasked and heated at 70 ° C for 9 hours for heat polymerization. The acrylic specimens were cut into small cubic pieces measuring 20×20×3 mm using a cutting machine and polished with metallographic abrasive paper. The specimens were randomized into 4 groups of control (artificial saliva) and HP and vinegar in 1:1, 1:3, and 3:1 ratios (three experimental groups). Then, they were immersed in the respective solutions for 8 hours/day for one month. Their surface roughness (Ra) was measured before and after immersion by a profilometer. The data were analyzed using a one-way analysis of variance (α=0.05). Results: The immersion of acrylic specimens in HP+vinegar in 1:1 and 1:3 ratios did not cause a significant change in their surface roughness (P&gt;0.05). However, the surface roughness significantly decreased after immersion in HP+vinegar in a 3:1 ratio (P=0.032). Despite the reduction in the surface roughness of specimens in the 3:1 group, the difference in surface roughness was not significant among the four groups after immersion (P&gt;0.05). Conclusion: Combinations of HP and vinegar in different ratios appear to be suitable for cleaning removable dentures due to their insignificant effects on the surface roughness of acrylic resin.

Mechanical properties and wear performance of denture base polymethyl methacrylate reinforced with nano Al2O3

Polymethyl methacrylate (PMMA) has been widely used as a material in dentistry. The deterioration of pure PMMA denture teeth is a significant issue that can alter the vertical dimensions of dentures. This study investigates the effect of aluminum oxide (Al2O3) nano-ceramic addition as reinforcements into the heat-cure acrylic resin denture teeth. The PMMA was reinforced with Al2O3 concentrations of 1, 3, 5, and 10 wt.%. The PMMA without ceramic addition is produced for comparison purposes. The color change, densification, microhardness, and compressive properties of the produced PMMA resin and its composites were investigated to detect the effect of Al2O3 nano ceramic addition on the physical and mechanical properties. Furthermore, the microstructure was also performed using scanning electron microscopy (SEM) analysis. A chewing simulator was utilized to conduct two-body wear testing, employing a human enamel antagonist. The wear behavior of the PMMA and their composites were assessed by measuring the weight loss after submitting them to 37,500 cycles. The SEM microstructure analysis revealed sound specimens of PMMA reinforced with 0, 1, 3, and 5 wt.% Al2O3 without any porosity and micro defects using the applied production procedures. In contrast, the aggregated sites and propagation of cracks were detected for the PMMA/10 wt.% Al2O3 specimen. The densification and hardness properties of the produced PMMA composites improved with increasing the Al2O3 additions. The microhardness of PMMA/10 wt.% Al2O3 improved by around 233% compared to the PMMA matrix. The higher compressive properties were detected for the PMMA/5 wt.% Al2O3 composite specimen with ultimate compressive strength (UCS) of 54.75 MPa and yield strength (YS) of 45.6 MPa and improved than the PMMA matrix by around 98 % and 117 %, respectively. In addition, incorporating Al2O3 nano-ceramic particles into a PMMA matrix revealed a significant improvement in the wear resistance of the produced composites compared to the PMMA matrix.

Impact strength of heat-cured acrylic resin after immersion in tobacco leaf (Nicotiana tabacum L.) effervescent tablets: An experimental study

Abstract Aim: To determine the effect of immersing heat-cured acrylic resin on tobacco leaf extract (TLE) effervescent tablets 75% on the impact strength. Materials and Methods: This research used an experimental design. Rectangular acrylic resin with a size of 60 mm × 12 mm × 3 mm, according to American Standards for Testing and Materials, was used. The samples were divided into three groups: immersed in distilled water as a negative control group, immersed in a solution of TLE effervescent tablets with a concentration of 75%, and immersed in commercially available dental cleansers as a positive control group. The immersion of the samples was carried out for 16 days which was equivalent to cleaning 30 min per day for 2 years. TLE effervescent tablets were compared with commercially available dental cleansers. Next, the impact strength of the sample was tested. Results: The one-way analysis of variance test results showed a P-value &lt;0.005, that is, a significant difference in each treatment group’s impact strength of heat-cured acrylic resin denture bases. The results of the post hoc test (least significance difference; LSD) showed that there is no significant difference in the impact strength of immersed acrylic in 75% TLE effervescent tablets with aquades compared to denture commercially available dental cleansers. Conclusions: 75% TLE effervescent tablets as a denture cleanser have the effect of reducing the impact strength of heat-cured acrylic resin type with a soaking time of 16 days, which is equivalent to cleaning 30 min per day for 2 years. The limitation of this research is the type of heat-cured acrylic used only from one brand, maybe different brands will give different results, so further testing is needed to prove it.

Ultimate flexural strength and Young’s modulus analysis of denture base resins for masked stereolithography 3D printing technology

of the study is to investigate the ultimate flexural strength and Young’s modulus of some materials, which can be used for complete denture fabrication by Masked stereolithography 3D printing technology.Three groups of five specimens each were fabricated. Two of the groups are 3D printed by Masked SLA 3D printer of two commonly used denture base resins. The third group is set to be a control as the specimens were fabricated of a heat-curing acrylic resin. A three-point flexural test tested the objects, and the data collected was used to determine ultimate flexural strength and Young’s modulus calculation. All the results are compared to the ISO Standard 20795-1.The data shows that the mean ultimate flexural strength of the 3D printed specimens is 87 MPa - 89 MPa. Their results are very similar to those for the heat-curing acrylic resin, which means the ultimate flexural strength is 93 MPa. The mean Young’s modulus obtained for the first group of 3D printed specimens is 2263.21 MPa and 2377.44 MPa for the second one. As for the control group, 2396.06 MPa is achieved. When ISO Standard 20795-1 is inspected, all the data obtained covers the minimum requirements.The limitations of the study concern to some additional factors that should be observed for more detailed evaluation. For example, the level of the final polymerization of light-curing resins for 3D printing, their ability to washstand to different defect and denture-bearing area characteristics (the notch for the labial and buccal frenulum, chambers for torus release, etc.), the ability of the materials to withstand to cyclic load, etc.3D printing is faster and cheaper than conventional methods for complete denture fabrication. The knowledge about the mechanical properties of the different materials for 3D printing is very valuable for properly selecting a material and approach for complete denture fabrication.Nowadays, 3D printing is essential in dentistry. For this reason, observation and knowledge of the raw materials properties is very important for the proper choice of a material and/or technology for each clinical case.

Effect of Hydroxyapatite Nanoparticles Addition on Water Sorption and Water Solubility of Heat-Cured Acrylic Resin Material

Effect of Hydroxyapatite Nanoparticles Addition on Water Sorption and Water Solubility of Heat-Cured Acrylic Resin Material

Effect of Hydroxyapatite Nanoparticles Addition on Water Sorption and Water Solubility of Heat-Cured Acrylic Resin Material

Effect of Hydroxyapatite Nanoparticles Addition on Water Sorption and Water Solubility of Heat-Cured Acrylic Resin Material

The impact of soaking heat-cured acrylic resin’s surface roughness in turmeric tamarind solution

Background: Dentures are a solution for the issue of tooth loss. Heat-cured acrylic resin is a common base material for dentures in dentistry. When exposed to acids frequently, the acrylic plate's surface becomes rough. Because of their health advantages, turmeric tamarind herb is commonly taken. Turmeric rhizomes and tamarind fruit are used to make herbal turmeric tamarind. The citric acid in tamarind fruit reduces the surface tension of acrylic resin that has undergone heat curing, increasing porosity and roughness. Materials and Method: 24 heat-cured acrylic resin plates that were pretested and divided into two groups of packed and unpackaged tamarind turmeric herbs were used in the laboratory experiment. The pH value of each group was measured. Each group's 12 samples were soaked for 1, 3, 5, or 7 days before the roughness was gauged and examined. Result: An analysis of the data using the two-way ANOVA test revealed a significant difference between the length of the immersion and the surface roughness of the heat-cured acrylic resin of 0.023 (0.005). However, the difference between the packaged and unpackaged turmeric tamarind groups was just 0.131 (&gt; 0.005). Conclusion: The harshness of the heat-cured acrylic resin was altered by the soaked time in the tamarind turmeric herb. The development of roughness can be affected by some factors, including the presence of acids, especially citric acid, liquid absorption, pH, the breaking down of polymer bonds, the level of hydrogen ions, and improper packing methods.

Biomechanical Behavior of a 3D-Printed Denture Base Material.

To evaluate relevant material properties (flexural strength [σf], elastic modulus [E], water sorption [Wsp] and solubility [Wsl], and biocompatibility) of an additive manufacturing (AM) polymer vs a heat-curing acrylic resin (AR; control) for the manufacture of complete dentures, testing the hypothesis that fabrications from both materials would present acceptable material properties for clinical use. The σf, E, Wsp, and Wsl were evaluated according to the ISO 20795-1:2013 standard, and the biocompatibility was evaluated using MTT and SRB assays. Disk-shaped specimens were fabricated and used for Wsp (n = 5), Wsl (n = 5), and biocompatibility (n = 3) testing. For assessment of σf and E, bar-shaped specimens (n = 30) were fabricated and stored in 37°C distilled water for 48 hours or 6 months before flexural testing in a universal testing machine with a constant displacement rate (5 ± 1 mm/minute). Data from σf, E, Wsp, Wsl, and biocompatibility tests were statistically analyzed using Student t test (α = .05). Weibull analysis was also used for σf and E data. Significant differences between the two materials were found for the evaluated material properties. Water storage for 6 months did not affect the flexural strength of the AM polymer, but this material showed inadequate σf and Wsl values. Despite adequate biocompatibility and strength stability after 6 months of water storage, the AM polymer recommended for complete dentures needs further development to improve the material properties evaluated in this study.

Analysis of the Microstructural and Mechanical Properties of 3D-Printed Removable Partial Denture Base Materials

ABSTRACT Background: Recent advancements in three-dimensional (3D) printing have introduced novel materials for removable partial dentures (RPD) base fabrication, promising improved mechanical properties, and biocompatibility. Materials and Methods: In this study, three different RPD base materials were evaluated: conventional heat-cured acrylic resin (Control), biocompatible 3D-printed resin (Test Group A), and a novel nanocomposite 3D-printed resin (Test Group B). A total of 30 standardized RPD base specimens (n = 10 per group) were fabricated according to established protocols. Microstructural analysis was performed using scanning electron microscopy (SEM), and the mechanical properties, including flexural strength and modulus, were determined using a universal testing machine. Results: Microstructural analysis revealed distinct differences among the materials. SEM images showed a well-defined and homogeneous microstructure in Test Group B, while Test Group A exhibited fewer voids compared to the Control group. Mechanical testing results indicated that Test Group B had the highest flexural strength (120 ± 5 MPa), followed by Test Group A (90 ± 4 MPa), and the Control group (75 ± 3 MPa). Similarly, Test Group B demonstrated the highest flexural modulus (3.5 ± 0.2 GPa), followed by Test Group A (2.8 ± 0.1 GPa), and the Control group (2.1 ± 0.1 GPa). Conclusion: These findings suggest that 3D-printed RPD base materials, particularly nanocomposite resins, hold promise for improving the overall quality and durability of removable partial dentures.

Effect of Beverage Solutions on Flexural Strength of PEEK CAD –CAM, 3D Printing Denture Base and Heat Cure Acrylic Resin Denture Base Materials

This research was to evaluate the effect of distilled water (D.W.), tea, coffee, and cola on flexural strength of PEEK CAD-CAM, 3D printing and heat cure acrylic resin denture base at different durations (6, 12and 24 days). Material used in this research are PEEK, 3D printing and Heat cure acrylic resin with dimension (64 × 10 × 3.3 ±0.2 mm, ISO 20795- 1:201320) for each tested material. Total number of samples are n= (195) samples, Control samples n=15, experimental samples n=180.The control samples were non immersed in beverage media. The experimental samples were immersed in beverage media (distilled water, tea, coffee, and cola) for evaluating the flexural strength at different time which are (6, 12 and 24 days), then all collecting data were statically analyzed by spss version 25, by means of Descriptive statistics, analysis of Variance (ANOVA) and Duncan multiple range tests at p ≤ 0.05. The beverage solutions had been non significantly decreased the flexural strength and this decreasing worst as the immer sion periods increased, the most decreasing in flexural strength o f PEEK denture base was achieved in 24 immersion days in cola (252.0960 MPa ±5.19825) followed by coffee (253.4360 MPa ± 6.60975) followed by tea(253.7780 MPa ± 6.44697) followed by distilled water (254.1420 MPa ±7.41318) as comparing with control(260.2420MPa ±5.08412), the most decreasing in flexur al strength of 3D printing denture base was achieved in 24 immersion days in cola (103.1680 MPa ±12.26532) followed by coffee (105.4360 MPa ±12.36951) followed by tea (10 7.4530MPa ±11.47399) followed by distilled water (109.1320 MPa ±11.66156) as comparing with control(119.7140 MPa ± 12.25421), the most decreasing in flexural strength of heat cure acrylic resin denture base was achieved in 24 immersion days in cola (118.5640MPa ±13.06764) follow ed by coffee (122.3640MPa ± 9.78213) followed by tea( 123.5600MPa ±14.05144) followed by distilled water (126.3620 MPa ± 11.35254) as comparing with control (134.6420 MPa ± 9.79330) at p ≤ 0.05. All beverage media had been negatively aff ected the flexural strength of all experimental materials and as t he immersion periods increased the affect became worst. The aggressive effect was in cola followed by coffee followed by tea and the least effect was in D.W. beverage media. The worst immersion period was 24 then 12 and 6 days. for all tests use but this affect was non significantly.

Effect of Beverage Solutions on Surface Roughness of PEEK CAD –CAM, 3D Printing Denture Base and Heat Cure Acrylic Resin Denture Base Materials

The Aim: The aim of this research was to investigate how distilled water, tea, coffee, and cola affected the surface roughness of poly ether ether ketone CAD-CAM, 3D printing, and heat cure acrylic resin denture bases at specific intervals (6 ,12days). Materials and Methods: Disk shape 10 mm (diameter) ×2 m m (thickness), manufactured from materials used which were PEEK, 3D printing and heat cure acrylic resin. Total number of samples are n= (75) samples, control samples not immersed in beverage media n= 15, experimental samples immersed in beverage solutions (distilled water, tea, coffee and cola) n=60 for evaluating the surface roughness at (6, 12 and 24 days) .Then all collecting data were statically analyzed by spss v ersion 25, by means of descriptive statistics, analysis of variance (ANOVA) and duncan multiple range tests at p ≤ 0.05. The Results: The results revealed a significant increase in surface roughness in all beverage solutions at p ≤ 0.0 5. Conclusions: All beverage solutions had a negative effect on surface roughness of all experimental materials, the surface roughness increased. cola had the most aggressive effect followed by coffee then tea and distilled water have the least ef fect.

Evaluation of Surface Hardness of Heat Cure Acrylic Resin Reinforce by Nano Al2O3 After Polishing with Different Materials

The goal of this research was to determine the surface hardness of heat cure acrylic resin reinforced with Nano Al2O3 after polishing with various materials. Materials and methods: - The 70 rectangular samples were made of a pink impact resistant thermoset acrylic (Vertex, Implacryl, The Netherlands) (65mm long x 10mm diameter x 3mm thick). Following polishing with each material (pumice stone, diamond suspension, colloidal silica), the surface roughness of each sample was determined using the Profilometer surface roughness instrument. The sample surface was glued to the profiler's horizontal base in a very flat position, and the stylus (the profiler's needle) was moved across each sample surface three times in three different directions over a distance of 1.7 mm. were separated into (7) groups were determined by the concentration of Nano powder, Group (A) Control without adding Nano filler of (Al2O3) (10) specimens, Group (B) Polishing with pumice Al2O3 (1%) (10) specimens, Group (C) Polishing with pumice Al2O3 (1.5 %) (10) specimens, Group (D) Polishing with Colloidal Al2O3 (1%) (10) specimens, Group (E) Polishing with Colloidal Al2O3 (1.5%) (10) specimens, Group (F) Polishing with Diamond Al2O3 (1%) (10) specimens, and Group (G) Polishing with Diamond Al2O3 (1.5%) (10) specimens. Data were statistically analyzed using statistical package for social science (SPSS), and the (ANOVA) test is used to determine whether the statistical hypothesis is true. Results: - For the hardness readings the higher mean value of hardness test found in group(D) (1%) polished by colloidal silica (82.74), then group (F)(1.5%)polished by colloidal(82.18), then group (F)(1%)polished by diamond( 81.12), then group(G)(1.5%)polished by diamond( 80.62),then group(C)(1.5%)polished with pumice(80.34),then group(B)(1%) polished with pumice(80.2),then at least group (A)control(80.18). Each of the three groups had a statistically significant difference with Highly sign. (P&lt;0.01). Conclusions: -Specimens of acrylic reinforcement with adding 1.5% of Nano AL2O3 and polished with (colloidal silica, diamond suspension, and pumice, respectively) sequentially showed highly surface hardness then

Comparative Evaluation to Surface Roughness of Modified Heat Cured Acrylic Resin by Zinc Oxide Nanoparticles and CAD/CAM Denture Base Materials - In Vitro Study

One of the most promising CAD/CAM approaches is milling denture base materials from highly condensed pre-polymerized resin discs. In an effort to overcome the disadvantages of acrylic resin denture base materials, nano-filler materials have been added as well as denture base chemistry adjusted to strengthen the denture base.This eliminates disadvantages associated with polymerization shrinkage compared to conventional heat-cured acrylic resin. Aim of this study: evaluate the surface roughness of PMMA acrylic resin after strengthening the denture- base by addition of zinc oxide nano-filler material to acrylic resin PMMA with concentration (1%) and compare with milled CAD/CAM and non-modified heat-cured PMMA denture base materials. Materials and methods: thirty specimens of acrylic resin PMMA were prepared and divided into three groups 10 specimens for each groups as follows; Control Group (Group1) without ZnO nanoparticles ; Group (2) with (1%) by weight of ZnO nanoparticles ; Group (3) milled CAD/CAM.Each specimen is of dimension ( 10 x 10 x 3 ) in mm and was fabricated using conventional processing method and milling the CAD/CAM blocks .Results: showed the lowest mean value was recorded by milled CAD/CAM (0.230 Ra) Then the non-significant reduction with mean value (0.312 Ra) by PMMA+ ZnO 1% and highest mean value of surface roughness was recorded by pure PMMA without additive (0.327 Ra).Conclusions: There were significant differences between control group PMMA and milled (CAD/CAM) with slight reduction of surface roughness of PMMA with (1%) Zno nanoparticles.

Effect of Aloe Vera Extract in Inhibit of Candida albicans on Cured Acrylic Resin Plates

Introduction: Removable dentures are either whole or partial. Fixed dentures are firmly affixed to the patient's teeth. Dentures reduce functional problems caused by tooth loss, but many individuals don't realize how crucial cleaning them is. Long-term denture use can hinder the tongue and saliva's cleaning of the dental mucosa. Thus, Candida albicans cling better to denture bases and primary agen in candidiasis oral. Aloe vera leaves contain six antimicrobial compounds that prevent the growth of various fungi, bacteria, and viruses, including Candida albicans and Staphylococcus pyogen. Objective: Knowing the effect of aloe vera extract (Aloe vera) with a concentration. Methods: The research method is True Experimental Laboratory, which uses a research design in post-test-only control groups. The Kruskal-Wallis test was used to analyze and interpret the research data results, and the Mann-Whitney U test was used as a follow-up analysis. Results: The normality test results showed a p-value of 0.033 in the control group of aquades smaller than 0.05. This proves that the control equates are generally not distributed because the p-value is smaller than 0.05 (p-value 0. The p-value 0.05 was obtained in the control group, proving that the control group is normally distributed. In the homogeneity test, a p-value of 0.000, smaller than 0.05, is obtained. This proves that the test data results in the control and treatment groups are not homogeneous. Conclus inhibits the development of Candida albicans in heat-cured acrylic resin.

Impact of nylon versus heat cure acrylic resin on microbial adhesion of closed hollowed obturators

Purpose This study aimed to evaluate the effect of nylon versus heat-cure acrylic resin on microbial adhesion of a closed hollowed obturator. Patients and methods Twelve male patients with a unilaterally acquired maxillary defect (Aramany Class IV) were chosen from the outpatient clinic of the Prosthodontics Department at the Faculty of Dentistry, Sinai University (Kantara branch). These patients were divided into two equal groups: group I was provided with an obturator made of heat-cured acrylic resin (P.M.M.A.-Vertex), while group II received an obturator made of thermopress resin (nylon breflex, 2nd edition). Each group underwent microbial evaluation through follow-up recall visits at 2 and 4 weeks. The results were recorded, tabulated, and subjected to statistical analysis. Results There is a significant difference between group I and group II. The conventional acrylic resin group showed higher bacterial adhesion than the nylon. Conclusion Within the limitations of the study, a closed hollow bulb constructed with thermopress resin exhibits reduced bacterial colonization when compared to heat-cured acrylic resin.

Clinical Evaluation of Masticatory Performance of Pre and Post-mandibular Guidance Therapy in Hemi-mandibulectomy Patients: A Quasi-experimental Study

Introduction: Surgical removal of the lower jaw is the most common cause of mandibular deviation due to benign or malignant neoplasms. The Palatal Guide Flange Prosthesis (PGFP) is a recommended corrective appliance to reduce this clinical manifestation. The primary goals of rehabilitation with PGFP are to train the mandibular muscles and restore a healthy occlusal relationship so that the patient can effectively control their mouth opening and closing movements. In the present article, the Masticatory Performance (MP) of patients who had undergone hemi-mandibulectomy surgery was evaluated both before and after receiving an interim PGFP. Aim: To clinically evaluate MP pre- and post-mandibular guidance therapy in hemi-mandibulectomy patients. Materials and Methods: A quasi-experimental study was conducted on patients selected from the Outpatient Department of the Department of Prosthodontics at Bharati Vidyapeeth Dental College and Hospital, Sangli, Maharashtra, India, from January 2021 to July 2022, and were included as the sample size for the study. A total of 10 samples were selected. The study design was quasi-experimental. All cancer patients had lost their mandibular continuity and showed mandibular deviation toward the affected side. PGFPs were fabricated using Heat Cure Acrylic Resin (DPI) for each participant (n=10). Corn flakes (Kellogg’s) were given to the participants to chew, and the samples were sieved using a US standard 8-mesh sieve and collected at three different time intervals: T0 (preprosthesis), T1 (8th week), and T2 (16th week post-prosthesis). Data were entered into Microsoft Excel Version 13 and analysed using IBM Statistical Package for the Social Sciences (SPSS) version 21.0. Descriptive and inferential statistics were used, including mean and standard deviation for continuous variables and frequency analysis for categorical variables. For categorical variables, a Chi-square proportion test was utilised, and MP was evaluated between T0-T1 and T0-T2. We utilised a 95% confidence interval and a p-value of less than 0.05. Results: When comparing the MP between T0, T1 and T2 time intervals, it was found that the difference in mean MP was statistically significant (p&lt;0.05), with MP increasing from 26.2% to 43% to 61.2%, respectively. Conclusion: The occlusion restored with the guide flange prosthesis, along with continuous use over a longer period, helped correct the deviated mandible and, in turn, improved the MP.