scholarly journals A Novel Polishing Paste (Mollusk Shells) for Poly (Methylmethacrylate)

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Nicole Guerra ◽  
Evelin Meneses ◽  
Stefany Caballero-García ◽  
Frank Mayta-Tovalino
Keyword(s):  
Surface Roughness ◽  
Acrylic Resin ◽  
Wilcoxon Test ◽  
Stone Surface ◽  
Pumice Stone ◽  
Mean Values ◽  
Significance Level ◽  
Mollusk Shells ◽  
Paired Wilcoxon Test

Objective. The aim of this study was to evaluate the effectiveness of a mollusk shells polishing paste (Donax obesulus) on the surface roughness of acrylic resin poly (methylmethacrylate) (PMMA). Methods. This study was an in vitro experimental design. A sample size of 72 was divided into 4 groups of n = 18 each. PMMA specimens were prepared and polished with the evaluated pastes using mollusk shells (experimental paste) and pumice stone. Surface roughness (μm) was measured using a profilometer after polishing the PMMA samples. The paired Wilcoxon test was used to evaluate the roughness values at 24 and 48 hours. Then, the Mann–Whitney U test was used to identify the differences between the effects of the two groups evaluated with a significance level of α = 0.05. Results. The roughness difference between the pastes under study was compared, and mean values of 0.50 ± 0.07 μm (mollusk shell paste group) and 0.45 ± 0.12 μm (pumice group) were obtained. No statistically significant differences were found between the experimental paste and pumice stone paste p = 0.309 . The specimens polished with pumice stone paste showed higher roughness values, while those polished with the experimental paste exhibited the lowest values. Conclusion. In summary, mollusk shells polishing paste had a decrease in roughness values compared to pumice, although these differences were not statistically significant.

scholarly journals Efficiency of different instruments used for composite filling polishing.

2021 ◽  
Vol 4 (1) ◽  
pp. 31-37
Author(s):  
Andrea-Csinszka Kovacs-Ivacson ◽  
Alexandra Mihaela Stoica ◽  
Mónika Kovacs ◽  
Mihai Pop
Keyword(s):  
Surface Roughness ◽  
Control Group ◽  
Mean Values ◽  
Significance Level ◽  
Caries Treatment ◽  
Before And After ◽  
Long Time ◽  
Surface Irregularities ◽  
Surface Staining

Abstract Introduction: Improper finishing and polishing of fillings leads to surface roughness of the restoration which leads to excessive plaque accumulation, gingival irritation, increased surface staining and poor aesthetics of restored teeth. Therefore, it is essential to use polishing instruments and pastes as a final step of simple caries treatment in order to achieve optimal long-time results. The aim of this study is to evaluate the efficiency of 4 different finishing and polishing instruments used for surface smoothening of aesthetic restorative materials in vitro. Materials and methods: 40 composite (Reality X) samples were prepared in vitro. Their surface irregularities were measured along 3 diagonals before and after polishing. Sof-Lex discs (3M Espe), rubber cones (Kenda), Arkansas stone (Fino) and polishing paste and a professional toothbrush (Kerr) were used for polishing. Each sample was polished under 5N pressure for 30 seconds at 3000 rpm. The surface roughness was than measured using a profilometer. Statistic analysis was performed using ANOVA and unpaired T-tests, the significance level was set at a value of p<0.05. Results: Based on the mean values, the smallest roughness was found in the control group- 0.11, while the highest in the rubber polishers and Arkansas stone group- 0.47 and 0.48. The values for the Sof-Lex disc group and the polishing paste-toothbrush group were 0.40 and 0.39. Statistical analysis showed no significant differences between the four groups. Conclusion: It is mandatory to use polishing tools in order to obtain a smooth surface of the restoration and avoid the unwanted long-term complications. Polishing using brush and abrasive paste produced the smoothest surface of the composite.

scholarly journals In vitro evaluation of microbial adhesion on the different surface roughness of acrylic resin specific for ocular prosthesis

2018 ◽  
Vol 12 (02) ◽  
pp. 176-183 ◽  
Author(s):  
Agda Marobo Andreotti ◽  
Cecília Alves De Sousa ◽  
Marcelo Coelho Goiato ◽  
Emily Vivianne Freitas da Silva ◽  
Cristiane Duque ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Staphylococcus Epidermidis ◽  
Microbial Growth ◽  
Acrylic Resin ◽  
Microbial Adhesion ◽  
Force Microscopy ◽  
Atomic Force ◽  
Colony Forming Units ◽  
Ocular Prostheses

ABSTRACT Objective: The purpose of this study was to evaluate the influence of surface roughness in biofilm formation of four microorganisms (Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans) on acrylic resin surface of ocular prostheses. Materials and Methods: Acrylic resin samples were divided into six groups according to polishing: Group 1200S (1200 grit + silica solution); Group 1200; Group 800; Group 400; Group 120 and Group unpolished. Surface roughness was measured using a profilometer and surface images obtained with atomic force microscopy. Microbial growth was evaluated after 4, 24, and 48 hours of incubation by counting colony-forming units. Statistical Analysis Used: For roughness, it was performed 1-way ANOVA and parametric Tukey test α5% (P ≤ 0.05). For CFU data found, it was applied Kruskal-Wallis and Mann-Whitney tests. Results: Group 120 and 400 presented the highest roughness values. For S. epidermidis and S. aureus, Group 1200S presented the lowest values of microbial growth. For E. faecalis at 4 hour, microbial growth was not observed. C. albicans did not adhere to the acrylic resin. Except for Group 1200S, different surface roughnesses did not statistically interfere with microbial adhesion and growth on acrylic surfaces of ocular prostheses. Conclusions: The roughness did not interfere with the microbial adhesion of the microorganisms evaluated. The use of silica decreases significantly microbial growth.

scholarly journals Effect of whitening dentifrices on the surface roughness of a nanohybrid composite resin

2016 ◽  
Vol 10 (02) ◽  
pp. 170-175 ◽  
Author(s):  
Gabriela Migliorin da Rosa ◽  
Luciana Mendonça da Silva ◽  
Márcio de Menezes ◽  
Hugo Felipe do Vale ◽  
Diego Ferreira Regalado ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Composite Resin ◽  
Wilcoxon Test ◽  
Control Group ◽  
Mean Values ◽  
Short Period ◽  
Significant Difference ◽  
Before And After ◽  
Nanohybrid Composite ◽  
One Way Anova

ABSTRACT Objectives: The present study verified the influence of whitening dentifrices on the surface roughness of a nanohybrid composite resin. Materials and Methods: Thirty-two specimens were prepared with Filtek™ Z350 XT (3M/ESPE) and randomly divided into four groups (n = 08) that were subjected to brushing simulation equivalent to the period of 1 month. The groups assessed were a control group with distilled water (G1), Colgate Total 12 Professional Clean (G2), Sensodyne Extra Whitener Extra Fresh (G3), and Colgate Luminous White (G4). A sequence of 90 cycles was performed for all the samples. The initial roughness of each group was analyzed by the Surface Roughness Tester (TR 200-TIME Group Inc., CA, USA). After the brushing period, the final roughness was measured, and the results were statistically analyzed using nonparametric Kruskal–Wallis and Dunn tests for intergroup roughness comparison in the time factor. For intragroup and “Δ Final − Initial” comparisons, the Wilcoxon test and (one-way) ANOVA were, respectively, performed (α = 0.05). Results: The roughness mean values before and after brushing showed no statistically significant difference when the different dentifrices were used. None of the dentifrices analyzed increased significantly the nanohybrid composite resin surface roughness in a 1 month of tooth brushing simulation. Conclusions: These results suggest that no hazardous effect on the roughness of nanohybrid composite resin can be expected when whitening dentifrices are used for a short period. Similar studies should be conducted to analyze other esthetic composite materials.

scholarly journals Effect of Denture Base Reinforcement Using Light Cured E- Glass Fibers on the Level of Salivary Immunoglobulin A

2018 ◽  
Vol 6 (11) ◽  
pp. 2168-2172
Author(s):  
Shady M. El Naggar ◽  
Mohamed I. Seif El Nasr ◽  
Hassan M. Sakr ◽  
Sherihan M. Eissa ◽  
Asmaa N. Elboraey ◽  
...  
Keyword(s):  
Immunoglobulin A ◽  
Acrylic Resin ◽  
Enzyme Linked Immunosorbent Assay ◽  
Complete Dentures ◽  
Denture Base ◽  
Mean Values ◽  
Glass Fibres ◽  
Significant Difference ◽  
Salivary Immunoglobulin A

BACKGROUND: A gap still exists between in vitro and clinical studies concerning the biocompatibility of the material in the oral environment and their potential to cause immunological undesirable side effects. The uses of glass fibres to improve the mechanical properties of acrylic resin denture base polymers are well documented in vitro. AIM: The present study aimed to evaluate the effect of denture base reinforcement using light-cured E- glass fibres mesh on the level of salivary immunoglobulin A (S-IgA) in patients wearing complete dentures. MATERIAL AND METHODS: Fourteen completely edentulous patients, in need of complete dentures, participated in the study. The patients were divided into two groups (n = 7) according to the treatment protocol. In the first group, patients received conventional heat-cured acrylic resin dentures. In the second group, the mandibular dentures were reinforced using light cured resin impregnated E glass fibres mesh. In both groups, salivary samples were collected using passive drool technique. The level IgA was assessed by enzyme-linked immunosorbent assay (ELISA) technique at different time intervals. Statistical analysis was carried out using one-way ANOVA followed by Tukey`s post-hoc test and independent t-test. The significant level was set at P ≤ 0.05. RESULTS: Acrylic resin dentures and reinforced ones demonstrated an increase in the mean values of IgA level at the end of the follow-up intervals. And this increase was statistically significant (P ≤ 0.05). Although, the reinforced dentures revealed higher mean values, there was no statistically significant difference between the two groups (P > 0.05) CONCLUSIONS: Within the limitations of the present study, the following could be concluded: (1) the insertion of complete dentures induced changes in the level of IgA; and (2) denture base reinforcement using light cured resin impregnated E-glass fibres mesh had a similar effect to that of heat cured acrylic resin on the level of IgA.

scholarly journals Adherence in vitro of Candida albicans to plasma treated acrylic resin. Effect of plasma parameters, surface roughness and salivary pellicle

2010 ◽  
Vol 55 (10) ◽  
pp. 763-770 ◽  
Author(s):  
Camila Andrade Zamperini ◽  
Ana Lucia Machado ◽  
Carlos Eduardo Vergani ◽  
Ana Claudia Pavarina ◽  
Eunice Terezinha Giampaolo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Candida Albicans ◽  
Acrylic Resin ◽  
Plasma Parameters ◽  
Salivary Pellicle

scholarly journals Influence of Silver Nanoparticles on the Specific Properties of Acrylic Resin for Ocular Prosthesis

2018 ◽  
Vol 11 (3) ◽  
pp. 1573-1581 ◽  
Author(s):  
Maha M. Turki ◽  
Faiza M. Abdul-Ameer
Keyword(s):  
Surface Roughness ◽  
Impact Strength ◽  
Flexural Strength ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Acrylic Resin ◽  
Control Group ◽  
Mean Values ◽  
The Mean ◽  
Group B

Scleral acrylic resin is widely used to synthesize ocular prosthesis. However, the properties of this material change over time, thus requiring the prosthesis to be refabricated. Many studies were conducted to improve these properties by reinforcing this material with nanoparticles. This study aims to evaluate the effect of silver nanoparticle powder on the mechanical properties (transverse flexural strength, impact strength, shear bond strength, surface microhardness, and surface roughness) of scleral acrylic resin used for ocular prostheses. Two concentrations were selected from the pilot study and evaluated for their effects on scleral acrylic resin properties. According to the pilot study, 0.01 and 0.02wt% AgNPs powder improved the transverse flexural strength, microhardness, and surface roughness compared with other percentages. The specimens in the main study were divided into (3) main groups, (50) specimens without additives (control group A), (50) experimental specimens (with 0.01wt% AgNPs group B), and (50) experimental specimens (with 0.02 wt% AgNPs group C). Each group was subdivided into (5) equal subgroups depending on the tests used. The data were studied using one way ANOVA and post hoc LSD test. At 0.01 wt% AgNPs addition, the mean values of transverse flexural strength insignificantly increased (p> 0.05), and those of impact strength and shear bond strength significantly increased (p< 0.05) compared with those of the control group. At 0.02 wt% AgNPs addition (group C), the mean value of transverse flexural strength significantly increased (p< 0.05), that of impact strength insignificantly increased (p> 0.05), and that of shear bond strength increased with high significance (p< 0.01) compared with those of the control group. Group C showed insignificant increase in the mean values of transverse flexural strength, impact strength, and shear bond strength (p. 0.05) compared with group B. The scleral acrylic resin added with 0.01 and 0.02 wt% AgNPs showed insignificant increase in microhardness and insignificant decrease in surface roughness. The addition of AgNPs powder in both concentrations improved the mechanical properties of scleral acrylic resin used for ocular prostheses.

scholarly journals Antimicrobial and mechanical acrylic resin properties with silver particles obtained from Fusarium oxysporum

2018 ◽  
Vol 21 (1) ◽  
pp. 96 ◽  
Author(s):  
Tabata Prado Sato ◽  
Celio Ilidio Conjo ◽  
Rodnei Dennis Rossoni ◽  
Juliana Campos Junqueira ◽  
Renata Marques de Melo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Fusarium Oxysporum ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Acrylic Resin ◽  
Control Group ◽  
Significant Difference ◽  
Color Alteration ◽  
Cie Lab

<p><strong>Objective: </strong>This study evaluated the effects of the incorporation of silver nanoparticles (AgNPs) obtained from <em>Fusarium oxysporum</em> on heat-activated acrylic resin (HAAR) and their influence on resin’s surface roughness, hardness, color alteration and antimicrobial capacity against <em>Candida albicans</em>. <strong>Material and Methods:</strong> For this, 50 discs of HAAR (2x5 mm) were produced and divided into three groups, Control: HAAR; Ag1: HAAR plus 0.539 mg of AgNPs; and Ag2: HAAR plus 1.1 mg of AgNPs. Knopp hardness (HK), surface roughness (Ra and Rz) and color alteration according to the CIE Lab were measured. Specimens were then evaluated <em>in vitro</em> with regard to <em>C. albicans</em> biofilm formation through formed colony count (CFU/mL). Scanning Electron Microscopy (SEM) and Atomic force microscopy (AFM) analyses were performed. <strong>Results:<em> </em></strong>The addition of AgNPs of both concentrations changed Ra, Rz and HK significantly. There was statistically significant difference for L (p=0.00); a*(p=0.00) and b*(p=0.00) parameters. There were no differences between Ag1 and Ag2 biofilm formation, but the comparison of both with the control group presented a significant reduction (p=0.0091) on biofilm formation. SEM and AFM images showed no signs of NPs clustering. <strong>Conclusion:</strong> It can be concluded tha AgNPs incorporation in HAAR was effective in reducing <em>C. albicans</em> activity, with a slight change in color and hardness of the material, being effective therefore, in regions such as the dental prostheses palate, which have lesser aesthetic appeal.</p><p><strong>Keywords</strong></p><p>Acrylic resins; Silver; Antimicrobial agents.</p>

scholarly journals Surface Roughness of Bulk Fill Composite after Simulated Toothbrushing with Different Dentifrices

2020 ◽  
Vol 8 (D) ◽  
pp. 166-172
Author(s):  
Ahmed Mohamed Elmarakby ◽  
Mahmoud Darwish ◽  
Yasser R. Souror ◽  
Ahmed Waly
Keyword(s):  
Surface Roughness ◽  
Chemical Composition ◽  
Analysis Of Variance ◽  
Composite Resin ◽  
In Vitro Study ◽  
Resin Composites ◽  
Composite Surface ◽  
Significance Level ◽  
Composite Resin Restorations

AIM: The aim of the current in vitro study was to evaluate the changes in surface roughness of bulk fill composites after simulated toothbrushing with different dentifrices. MATERIALS AND METHODS: Three types of bulk fill resin composites were used in this study; 27 specimens of each composite resin were randomly divided into three main groups (n = 9). Each main group was further subdivided into three subgroups (n = 3). Each group was subjected to simulated toothbrushing with three different dentifrices. One-way analysis of variance was used to evaluate the effect of brushing using dentifrices on the surface roughness of each type of composite resin, followed by Tukey’s test at a significance level of p ≤ 0.5%. RESULTS: Results revealed that different effects on composite surface roughness were detected after simulating toothbrushing with different dentifrices. Lacalut toothpaste abrades more with Filtek Bulk Fill, Tetric N-Ceram then Bulk Fill SDR. Crest 3D toothpaste abrades more with Tetric N-Ceram, Bulk Fill SDR then Filtek Bulk Fill. BlanX toothpaste abrades more with Tetric N-Ceram, Bulk Fill SDR then Filtek Bulk Fill. CONCLUSION: Chemical composition of both resin composites and dentifrices plays an important role in influencing the degree of surface roughness of bulk fill composite resin restorations.

scholarly journals In Vitro Evaluation of Physical and Mechanical Properties of Light-Curing Resin Cement: A Comparative Study

2020 ◽  
Vol 14 (01) ◽  
pp. 152-156
Author(s):  
Luís Felipe Espíndola-Castro ◽  
Oscar Felipe Fonseca de Brito ◽  
Larissa Gabrielle Assis Araújo ◽  
Izabella Luiza Aragão Santos ◽  
Gabriela Queiroz De Melo Monteiro
Keyword(s):  
Color Change ◽  
Surface Hardness ◽  
Color Stability ◽  
Resin Cement ◽  
The Other ◽  
Distilled Water ◽  
Water Control ◽  
Mean Values ◽  
Significance Level

Abstract Objective The aim of study was to evaluate in vitro the surface hardness, sorption, solubility, and color stability of three light-cured resin cements, namely RelyX Veneer (RLX), Variolink Veneer (VLK), and All Cem Veneer (ACV). Materials and Methods Cylindrical samples (15 × 1 mm) were made for each group using a metallic mold (n = 10). Vickers microhardness test was performed, and average hardness was calculated from three indentations (300 gf/15s) per sample. The sorption and solubility of the materials were evaluated according to ISO 4049:2009 based on three samples weighing: initial (m 1), after immersion in distilled water for 7 days (m 2), and final (after removal of all moisture [m 3]). The color change was observed using a digital spectrophotometer, at three different time points, baseline, 1 day, and 1 week of immersion in coffee and distilled water (control). Statistical Analysis Shapiro–Wilk test was used to analyze the normality of the data, and groups were compared using Kruskal–Wallis and Mann–Whitney tests. A significance level of 5% was used. Results RLX showed the highest microhardness mean values (36.96 VHN), but higher sorption (23.2 µg/mm3) and solubility (2.40 µg/mm3), with statistically significant differences with the other groups. For color stability, higher ∆E was observed for the samples immersed in coffee (p = 0.009). The VLK resin cement presented statistically significant differences from the other groups, with higher color changes in coffee at 1 day (15.14) and after 1 week (23.65). Conclusion RLX resin cement showed better hardness results. All materials tested performed satisfactorily for sorption and solubility according to ISO 4049:2009. All materials showed high-staining values after 1 week of immersion in coffee.

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