scholarly journals Effect of Different Denture Base Materials and Changed Mouth Temperature on Dimensional Stability of Complete Dentures

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Khalid A. O. Arafa

Background. Type of materials used in fabrication of denture base has an effect on dimension during denture base material processing and other factors related to clinical use.Objective. The study aims were to assess the dimensional stability including thermal changes of three different denture base materials.Methods. Ninety patients were selected to construct complete dentures with different denture base materials. They were randomly divided into three groups: group 1, patients with cobalt chrome metallic base; group 2, patients with heat curing acrylic resin fabricated by injection moulding technique; and group 3, patients with denture bases fabricated by conventional heat curing acrylic resin. The dimensional changes were assessed using digital caliper.Results. After the twelfth month, injection moulding acrylic resin had significantly the highest dimensional change followed by the conventional heat curing acrylic resin. There were no significant differences in the dimensions between the three types of denture base materials at normal mouth temperature, while, after hot tea drinking at 45°C, the dimensional change was significantly the highest in cobalt chrome metallic denture base group.Conclusion. Cobalt chrome metallic denture base has stable dimension compared to denture bases fabricated of acrylic resin but it was more affected by altered mouth temperature. The study was registered in the International Standard Randomized Controlled Trials Number (ISRCTN) registry with study ID (ISRCTN94238244).

2016 ◽  
Vol 6 (3) ◽  
pp. 171-176
Author(s):  
Sahar Elkholy

ABSTRACT Purpose This study aimed to evaluate the effects of the color of the cast on dimensional stability of visible light-cured (VLC) trial denture bases. Materials and Methods A total of 60 VLC acrylic resin trial denture bases were fabricated on different colored casts (20 white, 20 dark blue, and 20 dark brown casts) and were divided into two groups; each group consisted of 30 casts (10 white, 10 dark blue, and 10 dark brown). The gap between the base and the cast after 24 hours was measured at different points (left crest of the ridge, midpalatal area, and right crest of the ridge) at the posterior and premolar areas for group I and after 48 hours for group II by using a stereomicroscope. Results With brown cast, the trial denture base showed significant decrease in dimensional change in comparison with white and blue casts after 24 and 48 hours. Conclusion The dimensional accuracy of the VLC trial denture base could be improved by using dark-colored cast during construction, to ensure accurate maxillomandibular relationship and accurate evaluation of phonetics and esthetic of wax trial dentures. How to cite this article Elkholy S. Improving Dimensional Stability of Visible Light-cured Trial Denture Base using Different Colored Casts. J Contemp Dent 2016;6(3):171-176.


2020 ◽  
Vol 31 (5) ◽  
pp. 523-531
Author(s):  
Rafael Leonardo Xediek Consani ◽  
Andreia Bolzan de Paula ◽  
Ana Paula Piovezan Fugolin ◽  
Carmem S. Pfeifer

Abstract Thiourethane additives have been shown to improve properties in several dental polymer applications. The aim of this study was to verify the effect of the addition of thiourethane oligomers and acrylamide or isobornyl-based plasticizers on the physical properties of the denture base acrylic resin polymerized with microwaves. Thiourethane oligomer (TU) was synthetized and added to microwaved acrylic resin in proportions varying between 3 and 14 wt%. Separate experimental groups included the addition of dimethyl acrylamide (DMAM) and isobornyl methacrylate as plasticizers, at concentrations varying from 5 to 20 wt%. Samples were polymerized using microwave energy at 500 Watts for 3 min, deflasked at room temperature, stored in water at 37 °C for 24 h, and evaluated for: linear dimensional change, gloss, Knoop hardness, surface roughness, impact strength, yield strength, elastic modulus, toughness, yield strength, viscosity, glass transition temperature and network heterogeneity, and water sorption/solubility. Data were analyzed with ANOVA/Tukey’s post-hoc test (a=5%). The addition of TU led to properties that were similar or worse than the materials to which it was not added, except for dimensional stability. The impact on properties was statistically significant for all materials above 20% addition of TU. The addition of DMAM at 5 wt% or isobornyl methacrylate at 10 wt% improved yield strength and modulus, but increased water sorption and solubility. Except for dimensional stability, the addition of thiourethane oligomers to acrylic denture base materials compromised most tested properties. The use of DMAM and isobornyl methacrylate improved properties for selected compositions.


2018 ◽  
Vol 15 (4) ◽  
pp. 449-454
Author(s):  
Baghdad Science Journal

This work aims to investigate the tensile and compression strengths of heat- cured acrylic resin denture base material by adding styrene-butadiene (S- B) to polymethyl methacrylate (PMMA). The most well- known issue in prosthodontic practice is fracture of a denture base. All samples were a blend of (90%, 80%) PMMA and (10%, 20%) S- B powder melted in Oxolane (Tetra hydro furan). These samples were chopped down into specimens of dimensions 100x10x2.5mm to carry out the requirements of tensile tests. The compression strength test specimens were shaped into a cylinder with dimensions of 12.7mm in diameter and 20mm in length. The experimental results show a significant increase in both tensile and compression strengths when compared to control (standard) results for the preparation material.


2019 ◽  
Vol S (1) ◽  
pp. 7-10
Author(s):  
Ahmed Asim Saeed Al-Ali ◽  
◽  
Ammar k. Al-Noori ◽  
Amer A. Taqa ◽  
◽  
...  

Objectives: Compare tensile and transverse strength of new copolymers for denture base. Materials and methods: The specimens were prepared from heat cured acrylic resin with three types of additives: Acryester B, Ethoxycarbonylethylene, and Propenoic acid at a percentage of 5% and 10%. The tensile and transverse strains were tested, recorded and compared. Results: The analysis of variance display statistically significant difference. The p-value was 0.001 for each of tensile and transverse strain tests. Conclusions: The tensile strength of the novel copolymers increased. The transverse strength of some of the novel copolymers increased.


2006 ◽  
Vol 20 (3) ◽  
pp. 241-246 ◽  
Author(s):  
Rafael Leonardo Xediek Consani ◽  
Marcelo Ferraz Mesquita ◽  
Lourenço Correr-Sobrinho ◽  
Maurício Tanji

The aim of this study was to assess the displacement of posterior teeth in maxillary complete dentures stored in water at 37°C. Twenty acrylic resin-based maxillary complete dentures were constructed with the anterior teeth arranged in normal overlap and the posterior teeth in Angle class I. Metallic pins were placed on the labial cusp of the first premolars (PM), and on the mesiolabial cusp of the second molars (M). The final acrylic resin pressing was made in a metallic flask with aid of the RS tension system, and polymerized in a moist-hot cycle at 74°C for 9 hours. The dentures were deflasked after cooling in their own polymerizing water or after cooling in polymerizing water plus bench storage for 3 hours, and stored in water at 37°C for periods of 7, 30, and 90 days. Following deflasking and after each storage period tested, the PM-PM (premolar to premolar), M-M (molar to molar), LPM-LM (left premolar to left molar), and RPM-RM (right premolar to right molar) distances were measured with an STM Olympus microscope, with an accuracy of 0.0005 mm. Collected data were submitted to ANOVA and Tukey's test (5%). There was no statistically significant difference for the PM-PM, M-M, and LPM-LM distances after all storage periods when the flask cooling methods were considered. With exception of the RPM-RM distance after the 30-days water plus bench storage period, the other distances remained statistically stable.


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 ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document