scholarly journals Evaluation of some properties of recycled polymethylmethacrylate incorporated to the acrylic resin

2020 ◽  
Vol 11 (3) ◽  
pp. 2765-2771
Author(s):  
Amrah Y. Al Jmmal ◽  
Nada Z. Mohammed ◽  
Amer A. Taqa

Many attempts have been made enhancing properties of PMMA denture base material. Adding fillers to PMMA was a commonly used method to improve physical and mechanical properties. To estimate the effects of incorporating recycled polymethylmethacrylate with a different percentage with conventional heat-cured acrylic resin on some properties of heat-cured denture base resin. The recycled polymethylmethacrylate (Chaini-HK G) particles dissolved at (5%,10%,15%) was added to heat-cured polymethylmethacrylate (Spofadental, Czech Republic) polymer and mixed with a ratio of 2:1 with the polymethylmethacrylate monomer. A total number of specimens were 80, which divided into three experimental groups (5%, 10%, 15%) and control group. Each group have 20specimens. The surface hardness, water sorption, solubility and residual monomer of test groups measured as well as compared to that of control groups. Fourier transform infrared spectroscopy test (FTIR) was done for three experimental and control group. This study shows a statistically significant difference at (p<0.01) in the hardness of recycled polymethylmethacrylate incorporate material (10 %,15%) groups when compared with a control group; while recycled polymethylmethacrylate incorporated (5%) group show no significant difference, group with 15% shows the highest Vickers hardness value. The mean values of water sorption test solubility test and residual monomer were decreased with the increase of incorporating a percentage of recycled polymethylmethacrylate as compared to the mean value of the control group. The incorporation of recycled polymethylmethacrylate to heat acrylic resin at different percentage improves some of its properties.

2020 ◽  
Vol 5 (3) ◽  
pp. 126
Author(s):  
Gene Rizky Natalia Gunawan ◽  
Titik Ismiyati ◽  
Haryo Mustiko Dipoyono

Acrylic resin is a denture base material mostly used in the fabrication of removable partial denture and complete denture because it is easy to process, economical and aesthetically satisfying. However, the acrylic resin has a weakness i.e. residual monomer content which causes cytotoxic effect to human cells. Nano-silica coating could be used on the acrylic resin to reduce residual monomer content. The purpose of this study was to determine the effect of nano-silica coating concentration on the cytotoxicity of acrylic resin denture base material. Twenty-four acrylic resin disc-shaped specimens (5 mm in diameter and 2 mm in thickness) were divided into 4 groups (n=6), i.e. control, group with application of 0.5%,1%, and 2% nano silica coating. The specimens on the silica coating groups were silica coated using dip-coating method. After the coating was completed, the specimens were added into cell fibroblast culture (vero cell line). Cytotoxicity testswere done by MTT assay. The optical density was measured using ELISA plate reader to determine the percentage of cell viability. The highest mean of cell viability was shown in 0.5% concentration (96.78 ± 1.71) and the lowest mean was shown in the control group (80.32 ± 6.53). One-way ANOVA showed that there were significant differences among these groups. LSD tests showed that there was significant difference among all of the groups. This study concluded that nano silica coating concentration has a significant effect on the cytotoxicity of acrylic resin denture base materials.


2021 ◽  
Vol 25 (2) ◽  
pp. 108-113
Author(s):  
Ozlem Gurbuz Oflezer ◽  
Hakan Bahadır ◽  
Senem Ünver ◽  
Ceyhan Oflezer

Summary Background/Aim: Relining is defined as the procedure used to resurface the tissue side of a denture with new base material, thus producing an accurate adaptation is provided at the denture foundation area. During mastication, relined dentures have to withstand masticatory forces to prevent fracture. The aim of this study was to evaluate the flexural strength of acrylic resin denture base relined with different methods and materials. Material and Methods: Fourteen experimental groups and one control group were determined to consider different reline materials and processing methods. Acrylic resin specimens were prepared with the dimensions of 65× 10× 1.5 mm and reline materials (1.5 mm thickness) were placed on acrylic resins. Reline material was not used in control group specimens. Flexural strength values of relined and control specimens were measured with three-point bending test at a speed of 5 mm/min. Data were analyzed with using one way Anova and Student t tests. Results: The highest flexural strength values were shown in control group (86.51±1.08 MPa). There were significant differences among relined specimens (p< 0.05). For the relined specimens, the highest flexural strength values were found in the relined specimens with denture base material (77.90±1.93 MPa), and the lowest values were found in relined with autopolymerize acrylic material (59.81±1.50 MPa). Conclusions: Relining of the heat cure denture base material significantly decreases the flexural strength for all processing methods and materials.


Author(s):  
Eddy Dahar ◽  
Raudhatul Husna

Heat polymerized acrylic resin is the most common material used for making denture base because of it’s advantages. However, this material still hasn’t fulfill all the ideal requirements as a denture base. Some disadvantages that need to be fixed are low impact and transverse strength causing an easy base of fracture. Several attempts were made to improve the mechanical properties of heat polymerized acrylic resin materials by adding reinforcing materials. Zirconium oxide is one of chemical group that can be used as a reinforcing material and polypropylene fiber which is including in fiber reinforcing groups. This study aims to determine whether there is a difference in the effect of the addition of 5% ZrO2 nanoparticles and 2% chopped polypropylene fibers 6 mm in length on the impact and transverse strength of heat polymerized acrylic resin denture base material. The design of this study is a laboratory experimental and the number of samples in this study are 60 samples. The result of this study shows the mean value of the impact and transverse strength of heat polymerized acrylic resin with ZrO2 nanoparticles reinforced is greater than the control group and heat polymerized acrylic resin group with polypropylene fiber reinforced with significant difference, and the mean value of impact and transverse strength of heat polymerized acrylic resin with polypropylene fibers reinforced is greater than the control group with significant difference.


2018 ◽  
Vol 30 (1) ◽  
pp. 35 ◽  
Author(s):  
Edwin Tandra ◽  
Endang Wahyuningtyas ◽  
Erwan Sugiatno

Introduction: Acrylic resin is still the most commonly used denture base material due to its ideal properties. However, acrylic resin denture fractures are still considered a major unsolved problem thus the addition of nanoparticles as filler was performed to increase its mechanical properties. The purpose of this study was to discovered the effect of nanoparticles TiO2 on the flexural strength of acrylic resin denture plate. Method: This study used 27 heat-cured acrylic resin specimens sized 65 x 10 x 2.5 mm. The samples were divided into three concentration groups (n = 9), the control group; 1% of nanoparticles TiO2; and 3% of nanoparticles TiO2. The flexural strength was tested using the Universal Testing Machine. All data were analysed using the one-way ANOVA test with 95% confidence level then continued with the Least Significant Difference (LSD) test. Results: There were significant flexural strength differences in different concentration of nanoparticles TiO2. The highest flexural strength value was found in the 1% of nanoparticles TiO2 group (106.99 ± 6.09 MPa), whilst the lowest flexural strength value was found in the 3% of nanoparticles TiO2 group (91.64 ± 5.38 MPa). Significant flexural strength difference was found between the control group and the 1% of nanoparticles TiO2 group, and also between the 1% of nanoparticles TiO2 group with the 3% of nanoparticles TiO2 group (p < 0.05). Conclusion: From this study can be concluded that concentration of 1% of nanoparticles TiO2 was able to increase the flexural strength of acrylic resin denture plate.


2020 ◽  
Vol 5 (1) ◽  
pp. 36-43
Author(s):  
Gladis Aprilla Rizki ◽  
Sri Wahyuningsih Rais ◽  
Martha Mozartha

Alcoholic beverages can be consumed in any group age, and it may be consumed by an individual using denture. Fluid absorption by heat-cured acrylic resin as a material of a denture base was able to cause an increase in its surface roughness. Absorption of an organic solvent such as the ethanol in an alcoholic beverage(s) could even increase the effect. This study aimed to evaluate the effect of alcohol beverages on surface roughness of heat-cured acrylic resin denture base. Samples (n=24) were prepared from heat-cured acrylic resin (25x25x5 mm). They were divided into 4 groups and the pre-test surface roughness was measured. Samples of each group were immersed for 10 minutes into the solution (distilled water as the control group, beer, wine, and whiskey as the test groups). After stored in artificial saliva for 23 hours, the samples were immersed into the solution, completing a period of 24 hours. This procedure was performed for 7 consecutive days and the post-test surface roughness was measured. Data were statistically analyzed using the Kruskal-Walis test. There was a significant difference in surface roughness measurement before and after the immersion (p<0.05). Whiskey was most affecting the surface roughness of heat-cured acrylic resin denture base. Alcoholic beverages could increase the surface roughness of heat cure acrylic resin denture base. Keywords: Alcoholic beverages; Heat-cured acrylic denture base; Surface roughness


2020 ◽  
Vol 5 (2) ◽  
pp. 86
Author(s):  
Ardhianing Hardita ◽  
Titik Ismiyati ◽  
Endang Wahyuningtyas

Denture base material should have a good level of biocompatibility. Acrylic resin is frequently used as a denture base material, however it has a disadvantage of producing residual monomer. Residual monomer is known to have a cytotoxicity effect. Titanium dioxide (TiO2) nanoparticles are used as fillers due to their biocompatibility and ability to enhance the mechanical properties of acrylic resin. The addition of the material to acrylic resin could affect the amount of residual monomer. The aim of this study was to examine the effect of the addition of TiO2 nanoparticles as acrylic resin denture base filler on the cytotoxicity in fibroblast cells. The samples consisted of 24 heat cured acrylic resins in disc shape (5 mm in diameter and 2 mm in thickness), divided into 4 groups (n = 6): three groups given treatment with0.5%, 1%, 2% TiO2, respectively and one control group. Cell viability was measured with MTT assay. The results were tested with one way ANOVA with 95% confidence level followed by LSD post hoc test. The results showed that the highest percentage of cell viability was found in the treatment group of 0.5% TiO2 with value of 91.83 ± 1.75%, while the lowest value was seen in the treatment group of 2% TiO2 with value of 79.38 ± 3.34%. Significant differences were shown between the treatment groups of 0.5% and 2% TiO2, as well as between the control and treatment group with 2% TiO2. The conclusions of this research are the addition of TiO2 nanoparticles as acrylic resin denture base filler has an effect on cytotoxicity; the addition of 0.5% TiO2 nanoparticles filler results in lower cytotoxicity on fibroblast cells compared to the addition of 1% and 2% TiO2.  


2020 ◽  
pp. bmjstel-2020-000657
Author(s):  
Rebecca Singer ◽  
Grace Leo ◽  
Tessa Davis ◽  
Ben Lawton ◽  
Henry Goldstein ◽  
...  

Previous research has examined the utilisation of musical cues to improve the performance of cardiopulmonary resuscitation (CPR) delivered in training environments. We postulated a musical cue that is both contemporary and transcends cultures may improve CPR performance. Our aim was to establish whether chest compressions are performed with improved rate and depth if a song of a fixed beat (PinkFong’s ‘Baby Shark’ with a tempo of 115 beats per minute (bpm) and 15 beats in each verse) is played to a healthcare professional immediately before undertaking CPR compared to whale noises (a non-metronomic rhythm). 58 Participants of a paediatric conference (majority doctors) were randomly assigned to listen to a minute of Baby Shark (28) or whale song (30) and then undertake a minute of CPR. There was no significant difference in the mean compression rate between the Baby Shark and control groups, with the groups achieving 121 and 125 bpm, respectively (p=0.18). In relation to compression depth within the target zone, the Baby Shark group had more compressions completed within the target zone (55%) than the control group (39%) although this difference was not significant (p=0.08). Listening to Baby Shark prior to undertaking simulated CPR does not improve overall performance, but there is a potential tendency to improve adequate compression depth which may be beneficial in training exercises.


2021 ◽  
Vol 17 (1) ◽  
pp. 22-26
Author(s):  
Kadek Ayu Wirayuni ◽  
◽  
I Made Hendri Dwi Saputra ◽  

Introduction: The denture base is the part of the removable denture that is supported by good adaptation to the underlying oral tissue. Most of the denture bases are made of acrylic or polymethyl methacrylate resin, better known as PMMA. However, the acrylic resin also has disadvantages such as easily broken and absorbs liquids both water and chemicals. The chemical absorption like alcohol, ethanol, and some drinks that contain acidic materials will chemically be induced with acrylic resin and settle in the pores of the acrylic resin. The chemical damage or defect creates roughness on the surface of the acrylic resin which can cause cracking or crazing and a decrease in surface strength and hardness. Materials and Methods: The method used in this research was a laboratory experimental design with a post-test-only control group using 12 samples consisting of 2 different types of samples by measuring the surface roughness of the acrylic resin after immersing the sample with a predetermined time. Results and Discussions: One-way ANOVA test results showed a significant difference in surface roughness after the samples immersion with a value of p = 0.006 (p <0.05). Conclusions: Based on this research, can be concluded that there is an increase in the surface roughness of the heated polymerized acrylic resin for 3 hours and 4 hours of immersion. The longer the heated polymerized acrylic resin is soaked in arak hence the level of surface roughness increases.


2010 ◽  
Vol 92 (6) ◽  
pp. 463-465 ◽  
Author(s):  
James McDaid ◽  
Claire Reichl ◽  
Ihsan Hamzah ◽  
Samantha Fitter ◽  
Laura Harbach ◽  
...  

INTRODUCTION We observed that a number of patients presenting to our clinic with diverticular fistulation were taking nicorandil for angna. Recognised side effects of nicorandil include gastrointestinal and genital ulceration. The aim of our study was to determine whether nicorandil is an aetiological agent in diverticular fistulation. PATIENTS AND METHODS We conducted a case-control study of patients with diverticular disease related enteric fistulae. Two patient groups were identified: a study group of patients with diverticular fistulae, and a control group with uncomplicated diverticular disease. The proportion of patients who had ever used nicorandil was compared between the two groups. RESULTS A total of 153 case notes were analysed, 69 patients with fistulae and 84 control patients with uncomplicated diverticular disease. Female to male ratio in both groups was 2:1. The mean age was 71 years in the fistula group and 69 years in the control diverticular disease group (P = ns). Of those with colonic fistulae, 16% were taking nicorandil compared with 2% of the control group (odds ratio 7.8; 95% confidence interval 1.5–39.1; P = 0.008). There was no significant difference in rates of ischaemic heart disease between fistula and control groups. CONCLUSIONS Nicorandil is associated with fistula formation in diverticular disease.


2017 ◽  
Vol 10 (2) ◽  
pp. 11
Author(s):  
Bahruddin Thalib ◽  
Edy Machmud ◽  
Mochammad Dharmautama ◽  
Ervina Sari Surya ◽  
Asmawati Asmawati ◽  
...  

OBJECTIVE: The success of a dental dental implant treatment focuses on a phenomenon called osseointegration. Evaluation of Bone Area (BA) and Bone-Dental implant Contact (BIC) through histomorphometric analysis is the most widely used parameter to measure osseointegration. The aim of this study was to see post-placement Bone Dental implant Contact (BIC) value of dental implant coated and not coated with PRP.MATERIALS & METHODS: This study was an experimental laboratory conducted at Laboratory of Veterinary Faculty, Hasanuddin University. The sample was baby buck rabbit, aged 4-8 months old, weight 1500–2000 gram, divided into 2 groups each group consist of 12 rabbit, control group not coated with PRP and treatment group coated with PRP. Data analysis using SPSS version 20.0 (SPSS Inc., Chicago, IL, USA).RESULTS: There was a significant difference between the mean BIC values and the 20% increase in BIC values in LP1, LP2 and LP3 between treatment and control group on day 0, 3, 7, and 14.CONCLUSIONS: There was a difference in the average of post-placement BIC value of dental implant coated and not coated with PRP.


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