Dimensional accuracy of different impression techniques of partially edentulous mandibular arch

ABSTRACT Objective: The purpose of this in vitro study was to assess and compare the dimensional accuracy of three impression techniques: 1-step putty/light-body, 2-step putty/light-body, and the monophase technique. Methods: A partially edentulous standard stainless steel mandibular arch cast with reference points on the teeth was used to make the impressions. The anteroposterior and transverse distances were measured. All impressions were made with a polyvinyl siloxane using stock metallic (1- and 2-step putty/light-body techniques) or acrylic resin (monophase technique) trays. The monophase impressions were made using a light-body material and the 1- and 2-step putty/light-body impressions with putty and light-body materials. After impression procedures, the accuracy of each technique was assessed measuring the stone casts (n = 5) poured from the impressions using a microscope at 30x magnification and at 0.5 µm accuracy. The data were analyzed statistically using 2-way ANOVA and Tukey's test (p<0.05). Results: Stone casts made by all techniques had significantly negative linear changes (shrinkage). The anteroposterior distances showed more dimensional changes than the transverse distances. The edentulous side showed more shrinkage than the anteroposterior side. Conclusion: No differences between the impression techniques were found, but significant dimensional changes were observed.

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The Effect of Fiber Reinforcement on the Dimensional Changes of Poly Methyl Methacrylate Resin after Processing and after Immersion in Water: An in vitro Study

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1051 ◽

2011 ◽

Vol 12 (4) ◽

pp. 305-317 ◽

Cited By ~ 2

Author(s):

Sathish Abraham ◽

LM Ranganath ◽

Ravindra Ganguly Keshav Shet ◽

AG Rajesh

Keyword(s):

Methyl Methacrylate ◽

Fiber Reinforcement ◽

In Vitro Study ◽

Acrylic Resin ◽

High Impact ◽

Vitro Study ◽

Poly Methyl Methacrylate ◽

Dimensional Changes ◽

Heat Cure

ABSTRACT Aims and objectives To evaluate and compare the effect of fiber reinforcement on the dimensional changes of heat-cured poly (methyl methacrylate) resin after processing and immersion in water. Materials and methods Three different heat-cure resins were selected for the present study: (1) Nonreinforced heat-cure methyl methacrylate resin, (2) High Impact heat-cured methyl methacrylate resin and (3) Fiberglass reinforced methyl methacrylate resin. Ninety samples were prepared using three different resins and denture bases obtained for the same. The amount of space between the tissue surface and the cast in the anterior, middle and posterior regions is measured after processing and immersion in water for 17 days using a traveling microscope having a least count of 0.001 cm. Results Mean and standard deviation were calculated for the dimensional changes and were subjected to statistical analysis (Student t-test, unpaired). Among the three groups of resins, fiber reinforced heat-cured methyl methacrylate resin was found to be statistically highly significant in terms of dimensional changes when compared with the nonreinforced and high impact heat-cured resins. Conclusion Dimensional changes were evident in all the planes in the three groups studied and were in the following decreasing order—fiberglass reinforced heat-cured poly (methyl methacrylate) resin, high impact heat-cured poly (methyl methacrylate) resin and nonreinforced heat-cured poly (methyl methacrylate) resin. Clinical significance The fibers are added in order to increase the strength of acrylic resin. Considering only the strength may in turn affect the dimensional accuracy of the acrylic resin resulting in loss of retention and stability, affecting the fit of the denture. How to cite this article Ranganath LM, Shet RGK, AG Rajesh, Abraham S. The Effect of Fiber Reinforcement on the Dimensional Changes of Poly Methyl Methacrylate Resin after Processing and after Immersion in Water: An in vitro Study. J Contemp Dent Pract 2011;12(4):305-317.

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Comparison of Fracture Resistance in Thermal and Self-Curing Acrylic Resins—An In Vitro Study

Polymers ◽

10.3390/polym13081234 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1234

Author(s):

António Sérgio Silva ◽

Aurora Carvalho ◽

Pedro Barreiros ◽

Juliana de Sá ◽

Carlos Aroso ◽

...

Keyword(s):

Fracture Resistance ◽

Research Work ◽

Testing Machine ◽

In Vitro Study ◽

Dimensional Accuracy ◽

Acrylic Resin ◽

Thermosetting Resins ◽

Acrylic Resins ◽

The Difference

Thermal and self-curing acrylic resins are frequently and versatilely used in dental medicine since they are biocompatible, have no flavor or odor, have satisfactory thermal qualities and polishing capacity, and are easy and fast. Thus, given their widespread use, their fracture resistance behavior is especially important. In this research work, we comparatively analyzed the fracture resistance capacity of thermo and self-curing acrylic resins in vitro. Materials and Methods: Five prosthesis bases were created for each of the following acrylic resins: Lucitone®, ProBase®, and Megacryl®, which were submitted to different forces through the use of the CS® Dental Testing Machine, usually mobilized in the context of fatigue tests. To this end, a point was defined in the center of the anterior edge of the aforementioned acrylic resin bases, for which the peak tended until a fracture occurred. Thermosetting resins were, on average, more resistant to fracture than self-curable resins, although the difference was not statistically significant. The thermosetting resins of the Lucitone® and Probase® brands demonstrated behavior that was more resistant to fracture than the self-curing homologues, although the difference was not statistically significant. Thermosetting resins tended to be, on average, more resistant to fracture and exhibited the maximum values for impact strength, compressive strength, tensile strength, hardness, and dimensional accuracy than self-curing resins, regardless of brand.

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A Comparative Evaluation of Dimensional Accuracy and Surface Detail Reproduction of Four Hydrophilic Vinyl Polysiloxane Impression Materials Tested Under Dry, Moist, and Wet Conditions-An In Vitro Study

The Journal of Indian Prosthodontic Society ◽

10.1007/s13191-014-0365-z ◽

2014 ◽

Vol 14 (S1) ◽

pp. 59-66 ◽

Cited By ~ 1

Author(s):

Rahul Nagrath ◽

Manesh Lahori ◽

Manjari Agrawal

Keyword(s):

Comparative Evaluation ◽

In Vitro Study ◽

Dimensional Accuracy ◽

Vitro Study ◽

Impression Materials ◽

Surface Detail

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An in-vitro study to evaluate the accuracy of dies obtained from dual arch impression trays using addition silicone impression material and tray combinations

Health Renaissance ◽

10.3126/hren.v12i2.14114 ◽

2015 ◽

Vol 12 (2) ◽

pp. 111-117

Author(s):

P K Parajuli ◽

S George ◽

V Shenoy

Keyword(s):

In Vitro Study ◽

Dimensional Accuracy ◽

Acrylic Resin ◽

Simultaneous Recording ◽

T Test ◽

Impression Material ◽

Tooth Preparation ◽

Made In ◽

Plastic Trays

Background: Dual-arch impression technique allows the simultaneous recording of tooth preparation, opposing anatomic tooth and maxillomandibular relationship. The accuracy of reproduction of this easy and quick technique, however, has not been studied in detail in past. Objective: To compare the accuracy of the impressions made by using the same impression material in dual arch plastic trays, dual-arch metal trays and acrylic resin custom trays. Methods: The dies obtained from the addition silicone impressions made in dual-arch plastic trays, dual-arch metal trays and full arch acrylic resin custom trays were compared for the dimensional accuracy with the prepared typodont tooth as a control. Student’s paired t-test and unpaired t-test were used for the data analyses using the Statistical Package for Social Studies (SPSS) version 11.5. Results: The dies obtained from all the impression combinations showed increased dimension (acrylic resin custom trays 9.4 mm±0.048, dual-arch plastic trays 9.5 mm±0.035, dual-arch metal trays 9.41 mm±0.017) as compared to the dimension of control (9.39 mm±0.007). Conclusion: All the tray-impression material combinations showed variable accuracies. Full arch acrylic resin trays resulted in greatest accuracy whereas dual-arch plastic trays the least accuracy.Health Renaissance 2014;12(2): pp: 111-117

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