scholarly journals In Situ Evaluation of the Microbial Adhesion on a Hard Acrylic Resin and a Soft Liner Used in Removable Prostheses

2015 ◽  
Vol 28 (1) ◽  
pp. 65-71 ◽  
Author(s):  
Ana Gomes ◽  
Benedita Sampaio-Maia ◽  
Mario Vasconcelos ◽  
Patricia Fonseca ◽  
M Figueiral
Keyword(s):  
Acrylic Resin ◽  
Microbial Adhesion ◽  
Soft Liner

scholarly journals Hardness, compressive strength and resilience of complete denture lining materials: an in situ study

2020 ◽  
Vol 68 ◽  
Author(s):  
Hugo de CARVALHO JUNIOR ◽  
Vítor Hugo Marçal de CARVALHO ◽  
Roberta Tarkany BASTING
Keyword(s):  
Compressive Strength ◽  
Acrylic Resin ◽  
Time Intervals ◽  
Soft Liner ◽  
Term Evaluation ◽  
Materials Used ◽  
Tissue Conditioner ◽  
Hardness Values

ABSTRACT Objective The aim of this study was to evaluate the in situ hardness, compressive strength and resilience of soft lining materials used in total removable prostheses in different time intervals Methods total of 48 rectangular test specimens (10 x 3 x 2 mm) were fabricated of each of the polyvinylsiloxane-based soft liner (Mucopren Soft) and acrylic resin-based material (Trusoft), which were placed on total removable prostheses bases of 12 volunteers (n = 12). The hardness (Shore A), compressive strength (in MPa) and resilience (in Kgf/cm2) were evaluated in different time intervals: 0, 7, 30 and 60 days, at three different locations of the specimens surface. Results The two-way ANOVA and Tukey test showed that the polyvinylsiloxane-based soft liner presented higher hardness values (p = 0.0113) and higher compressive strength (p=0.0252) than the acrylic resin-based material at immediate and 7 days evaluations. The polyvinylsiloxane-based soft liner presented higher resilience values than the acrylic resin-based material at all times (p = 0.0133). Hardness and compressive strength were similar for both materials at 30 and 60 days evaluations. Conclusions For both materials,there was a tendency for an increase of hardness, compressive strength and resilience over time, influenced by the composition of the tissue conditioner. The polyvinylsiloxane-based soft liner presented higher hardness, compressive strength and resilience than the acrylic resin-based material, specially considering a long-term evaluation up to 60 days.

scholarly journals A Flexible, Highly Sensitive, and Selective Chemiresistive Gas Sensor Obtained by In Situ Photopolymerization of an Acrylic Resin in the Presence of MWCNTs

2018 ◽  
Vol 304 (2) ◽  
pp. 1800453 ◽  
Author(s):  
Lorenzo Vigna ◽  
Andrea Fasoli ◽  
Matteo Cocuzza ◽  
Fabrizio C. Pirri ◽  
Luisa D. Bozano ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Acrylic Resin ◽  
Highly Sensitive

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.

Selection of Consolidants for Use on the Tower of Belem / Auswahl eines Steinfestigers für den Turm von Belem

1998 ◽  
Vol 4 (6) ◽  
pp. 653-666 ◽  
Author(s):  
J. Delgado Rodrigues ◽  
A.P. Ferreiro Pinto ◽  
A.E. Charola ◽  
L. Aires-Barros ◽  
F.M.A. Henriques
Keyword(s):  
Air Pollution ◽  
Epoxy Resin ◽  
Good Condition ◽  
Acrylic Resin ◽  
Natural Weathering ◽  
Site Testing ◽  
Stone Consolidants ◽  
Final Selection ◽  
Selection Of

Abstract During the exterior conservation project of the Tower of Belem, Lisbon, it was noticed that although most of the Lioz limestone used in its construction was in good condition, some specific areas presented severe powdering and flaking deterioration patterns. These are mainly due to the effect of natural weathering, including anthropogenic air-pollution, on poorer quality Lioz limestone. Since the deterioration affects mainly the immediate surface and subsurface of the stone blocks, the application of stone consolidants was considered as the most appropriate solution for this problem. This paper describes the difficulties encountered in the evaluation of the tested consolidants-an ethyl silicate ester, an acrylic resin and an epoxy resin-applied in situ. The laboratory and on-site testing used in the final selection are described as well as the actual approach to consolidating the different areas that required this treatment.

scholarly journals Tensile Bond Strength of a Soft Liner to an Acrylic Resin after Primer Application and Thermocycling

2015 ◽  
Vol 18 (6) ◽  
pp. 1183-1187 ◽  
Author(s):  
Marcelo Coelho Goiato ◽  
Daniela Micheline dos Santos ◽  
Rodrigo Antonio de Medeiros ◽  
Aljomar José Vechiato Filho ◽  
Mário Alexandre Coelho Sinhoreti ◽  
...  
Keyword(s):  
Bond Strength ◽  
Acrylic Resin ◽  
Tensile Bond Strength ◽  
Soft Liner

Inhibiting microbial adhesion to denture base acrylic resin by titanium dioxide coating

2009 ◽  
Vol 36 (12) ◽  
pp. 902-908 ◽  
Author(s):  
T. ARAI ◽  
T. UEDA ◽  
T. SUGIYAMA ◽  
K. SAKURAI
Keyword(s):  
Titanium Dioxide ◽  
Acrylic Resin ◽  
Microbial Adhesion ◽  
Denture Base

scholarly journals Effect of Sealant Application and Thermal Cycling on Bond Strength of Tissue Conditioners to Acrylic Resin

2013 ◽  
Vol 24 (3) ◽  
pp. 247-252 ◽  
Author(s):  
Francisca Neta Cruz Soares Sampaio ◽  
Jose Renato Ribeiro Pinto ◽  
Cecilia Pedroso Turssi ◽  
Roberta Tarkany Basting
Keyword(s):  
Bond Strength ◽  
Thermal Cycling ◽  
Testing Machine ◽  
Acrylic Resin ◽  
Tensile Bond Strength ◽  
Thermal Cycles ◽  
Bond Failure ◽  
Universal Testing ◽  
Soft Liner ◽  
Tissue Conditioner

The aim of this study was to evaluate the effect of sealer application and thermal cycling on the bond strength between tissue conditioners and acrylic resin, and to observe the type of bond failure. Two hundred eighty-eight specimens (10x16x3 mm) were made of an acrylic resin (Lucitone 500, Dentsply) using a metal muffle. Specimens were divided into four groups according to the tissue conditioner (Coe-Comfort, GC or Dentusoft, Densell) used and whether or not a sealer (Eversoft Soft Liner Sealer, Myerson) was applied. Each of the four groups was subdivided into other six subgroups (n=12) to undergo thermocycling for 45, 90, 135, 180 or 210 cycles with a dwell time of 60 s, or to be left non thermocycled (control). Tensile bond strength was measured in a universal testing machine at a crosshead speed of 5 mm/min. Sealant application had no effect on the tensile bond strength of the relined acrylic resin, regardless of the tissue conditioner used (Coe-Comfort: p=0.306 and Dentusoft: p=0.1501). The number of thermal cycles had a significant effect on the tensile bond strength of the relined acrylic resin (Coe-Comfort: p=0.002 and Dentusoft: p<0.001). Both tissue conditioners presented similar bond strength to acrylic resin. For both tissue conditioners, sealer coatings had no influence on bond strength, while different numbers of thermal cycles affected that mechanical property.

scholarly journals Effect of Food Simulating Agents on the Hardness and Bond Strength of a Silicone Soft Liner to a Denture Base Acrylic Resin

2015 ◽  
Vol 9 (1) ◽  
pp. 402-408 ◽  
Author(s):  
A.A.R. Khaledi ◽  
M. Bahrani ◽  
S. Shirzadi
Keyword(s):  
Citric Acid ◽  
Bond Strength ◽  
Acrylic Resin ◽  
Tensile Bond Strength ◽  
Control Group ◽  
Denture Base ◽  
Bonding Failure ◽  
Base Resin ◽  
Soft Liner ◽  
Denture Base Resin

Statement of the Problem: Bonding failure between acrylic resin and soft liner material and also gradual loss of soft liner resiliency over time are two impending challenges frequently recognized with a denture base embraced with a resilient liner. Since patients drink various beverages, it is crucial to assess the influences of these beverages on physical characteristics of soft liners. Purpose: This in vitro study envisioned to assess the influence of food simulating agents (FSA) on the hardness of a silicone soft liner by employing a Shore A durometer test and also evaluate its bond strength to a denture base resin by using tensile bond strength test. Materials and Methods: To test the hardness of samples, 50 rectangular samples (40 mm × 10 mm × 3 mm) were prepared from a heat-polymerized polymethyl methacrylate (Meliodent). Mollosil, a commercially available silicone resilient liner, was provided and applied on the specimens following the manufacturer’s directions. In order to test tensile bond strength, 100 cylindrical specimens (30 mm × 10 mm) were fabricated. The liners were added between specimens with the thicknesses of 3 mm. The specimens were divided into 5 groups (n=10) and immersed in distilled water, heptane, citric acid, and 50% ethanol. For each test, we used 10 specimens as a baseline measurement; control group. All specimens were kept in dispersed containers at 37ºC for 12 days and all solutions were changed every day. The hardness was verified using a Shore A durometer and the tensile bond strength was examined by an Instron testing machine at a cross-head speed of 5 mm/min. The records were analyzed employing one-way ANOVA, Tukey’s HSD, and LSD tests. Results: The mean tensile bond strength ± standard deviation (SD) for Mollosil was as follows for each group: 3.1 ± 0.4 (water), 1.8 ± 0.4 (citric acid), 3.0 ± 0.4 (heptane), 1.2 ± 0.3 (50% ethanol), and 3.8 ± 0.4 (control). The hardness values for each group were: 28.7 ± 2.11 (water), 33.2 ± 2.82 (citric acid), 39.2 ± 4.8 (heptane), 32.3 ± 3.56 (50% ethanol) and 22.2 ± 2.08 (control). Mean values for hardness indicated that all of the food simulating agents significantly increased hardness of the Mollosil soft liner compared to the control group (p<0.05). The results of tensile bond strength depicted that water and FSA decreased the bond strength of the soft liner -denture base resin compared to the control group and it was statistically significant (p<0.05). Conclusion: The food simulating agents could influence the mechanical properties of silicone soft liners; hence, clinicians should inform their patients concerning their possible adverse effects and complications.

Sign in / Sign up

Export Citation Format

Share Document