Statement Of Problem: Impressions are made using high-viscosity putty vinyl polysiloxane impression materials in conjunction with disposable plastic stock trays. The impression materials have been shown to be dimensionally stable. However, it remains unclear if the disposable plastic stock trays are rigid enough to resist deformation thus yielding potentially unreliable results.
Purpose: This study evaluated the rigidity and ability to resist deformation of 6 commercially available disposable plastic stock trays and 1 metal stock tray when used in conjunction with a high-viscosity vinyl polysiloxane impression material.
Material And Methods: Ten impressions were made with 1 putty vinyl polysiloxane material (Reprosil Putty) using each of the 6 tested disposable plastic stock trays, Sani-Trays (perforated), Sani-Trays (nonperforated), COE Disposable Spacer Tray (perforated), COE Disposable Spacer Tray (nonperforated), Bosworth Tray-Aways (perforated), Track-it Trays (perforated), and 1 metal stock tray (nonperforated), Cadco Dental Products, as a control on a mandibular plastic model. The dimensions of the tray in cross section at the mandibular right first molar area were measured before, during, and after the impression procedures with an electronic digital caliper. The cross-arch dimensions of the tray were measured at similar intervals. One examiner made all measurements and each measurement was repeatable within +/-0.01 mm. A split plot repeated measures analysis of variance (ANOVA) was performed and 2-sided P -values were calculated (alpha=.05).
Results: The results indicated that the disposable plastic trays tested were not sufficiently rigid to resist deformation when used with very high-viscosity putty material. Metal stock trays showed significantly less change in cross-arch dimension than plastic trays (F(1.68)=11.25, P =.001). Metal stock trays also showed significantly less change in cross-sectional arch dimension than plastic trays (F(1.68)=15.15, P<.001).
Conclusion: When disposable plastic stock trays were tested in conjunction with very high-viscosity impression materials there was distortion of the tray both across the arch and in cross section.
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http://dx.doi.org/10.1016/j.prosdent.2004.07.020 | DOI Listing |
J Prosthodont
July 2024
Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
Purpose: To assess the accuracy of complete maxillary and mandibular edentulous arch scans obtained using two different intraoral scanners (IOSs), with and without scanning aids, and to compare these results to those obtained using conventional impression methods.
Materials And Methods: Two IOSs were used (TRIOS 4 [TRI] and Emerald S [EMR]) to scan maxillary and mandibular typodonts. The typodonts were scanned without scanning aids [TRI_WSA and EMR_WSA groups] (n = 10).
F1000Res
July 2024
Professor, Orthodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, Maharashtra, 442001, India.
Int J Oral Maxillofac Implants
August 2024
Purpose: To evaluate the dimensional accuracy of implant impressions obtained using five different tray types and two techniques.
Materials And Methods: A partially dentate maxillary Kennedy Class II model was created as a reference model through 3D printing. Then, implant analogs 4.
J Insect Sci
May 2023
USDA ARS Pollinating Insects Research Unit, Logan, UT 84322, USA.
Melittobia acasta Walker is one among other hymenopterous parasitoids of Megachile rotundata F. Commercial M. rotundata populations are employed to pollinate North American alfalfa for seed production.
View Article and Find Full Text PDFJ Prosthet Dent
May 2023
Associate Professor, Department of Prostodontics, Faculty of Dental Surgery, University of Lille, University Hospital Center of Lille (CHU Lille), Lille, France. Electronic address:
The treatment of infants with trisomy 21 (TS21) with a myostimulation plate can improve their development and quality of life. The manufacture of these plates requires an accurate cast of the maxilla, and their efficacy relies on their stability and retention. As such, the quality of the impression is a determining factor.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!