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Dental Materials Journal 2012The purpose of this study was to synthesize biomaterials from daily dental waste. Since alginate impression material contains silica and calcium salts, we aimed to...
The purpose of this study was to synthesize biomaterials from daily dental waste. Since alginate impression material contains silica and calcium salts, we aimed to synthesize calcium silicate cement from alginate impression material. Gypsum-based investment material was also investigated as control. X-ray diffraction analyses revealed that although firing the set gypsum-based and modified investment materials at 1,200°C produced calcium silicates, firing the set alginate impression material did not. However, we succeeded when firing the set blend of pre-fired set alginate impression material and gypsum at 1,200°C. SEM observations of the powder revealed that the featured porous structures of diatomite as an alginate impression material component appeared useful for synthesizing calcium silicates. Experimentally fabricated calcium silicate powder was successfully mixed with phosphoric acid solution and set by depositing the brushite. Therefore, we conclude that the production of calcium silicate cement material is possible from waste alginate impression material.
Topics: Alginates; Calcium Compounds; Calcium Sulfate; Dental Casting Investment; Dental Impression Materials; Dental Waste; Diatomaceous Earth; Green Chemistry Technology; Powders; Silicate Cement; Silicates; X-Ray Diffraction
PubMed: 22864217
DOI: 10.4012/dmj.2012-027 -
Journal of Biological Regulators and... 2021For dental impression of a prepared tooth, the goal is a void-free negative representation from which an accurate cast of a tooth and its surrounding tissue can be...
For dental impression of a prepared tooth, the goal is a void-free negative representation from which an accurate cast of a tooth and its surrounding tissue can be reproduced. This in-vitro study assessed and compared the reproduction accuracies of surface detail obtained with three different dental elastomeric impression materials: vinyl polysiloxane (VPS), vinyl polyether silicone (VPES), and polyether (PE). A stainless-steel model with two abutments was used, with impressions taken 10 times for each material, for 20 abutment impressions per group, using a two-phase, one-step technique (heavy body/light body). The impressions were removed and assessed for numbers of enclosed voids and open voids visible on the surface. The defect frequency was 95% for impressions with the VPS and VPES materials, and 30% for the PE material. No significant differences were seen for number of impressions with defects for VPS versus VPES. Significant differences were seen for VPS and VPES versus the PE material (P <.05). No significant differences were seen for the defect type distributions across these three impression materials. The PE impression material showed better accuracy for reproduction of surface detail of these dental impressions compared to the VPS and VPES impression materials.
Topics: Dental Impression Materials; Dental Impression Technique; Materials Testing; Models, Dental; Reproducibility of Results; Surface Properties
PubMed: 33435664
DOI: 10.23812/20-561-A -
Journal of the American Dental... Nov 1974
Topics: American Dental Association; Dental Impression Materials; Evaluation Studies as Topic; Humans; Technology, Dental; United States
PubMed: 4529960
DOI: 10.14219/jada.archive.1974.0535 -
Medicina Oral, Patologia Oral Y Cirugia... Apr 2009A 62-year-old man was referred for routine treatment of hyperplasia of the mucosa in the anterior lower jaw. An oroantral fistula was detected in the right superior...
A 62-year-old man was referred for routine treatment of hyperplasia of the mucosa in the anterior lower jaw. An oroantral fistula was detected in the right superior alveolar ridge. The patient had no complaints. Plain radiographs showed a radiopaque foreign body in the posterior region associated with opacification of the maxillary sinus. Computed tomography showed the same hyperdense foreign body located in the posterior lower part of the sinus and an abnormal soft tissue mass in the entire right maxillary sinus. When asked about sinusitis, the patient mentioned occasional episodes of pus taste and intermittent crises of headache lasting for one week. The patient has been edentulous for 20 years. Sinus debridement was performed and the oroantral fistula was closed. The clinical suspicion of the presence of zinc oxide-eugenol paste was confirmed by microscopical and chemical analysis. After 6 months of follow-up, the fistula continued to be closed and sinusitis did not recur. This clinical case of maxillary chronic sinusitis illustrates a different odontogenic origin.
Topics: Alveolar Process; Chronic Disease; Dental Impression Materials; Foreign Bodies; Humans; Male; Maxillary Sinus; Maxillary Sinusitis; Middle Aged; Oroantral Fistula; Radiography; Zinc Oxide-Eugenol Cement
PubMed: 19333183
DOI: No ID Found -
British Dental Journal Mar 1973
Topics: Adult; Antigens; Burning Mouth Syndrome; Dental Impression Materials; Dermatitis, Contact; Drug Eruptions; Drug Hypersensitivity; Face; Female; Humans; Neck; Skin Tests
PubMed: 4269671
DOI: 10.1038/sj.bdj.4802981 -
The International Journal of... 2009Materials used for dental impressions are usually safe. This study describes a case of fatal anaphylaxis that appeared immediately after the oral mucosa came into...
Materials used for dental impressions are usually safe. This study describes a case of fatal anaphylaxis that appeared immediately after the oral mucosa came into contact with an alginate paste used for dental impressions. The cadaveric examination and the postmortem toxicology report confirmed that the cause of death was anaphylactic shock. The patient was affected by both cardiovascular and lung diseases that worsened the condition and forbade the use of epinephrine. To the authors' knowledge, dental impression materials, and alginate in particular, have not been reported previously as being a cause of anaphylaxis.
Topics: Aged; Alginates; Anaphylaxis; Dental Impression Materials; Fatal Outcome; Humans; Male
PubMed: 19260424
DOI: No ID Found -
Journal of the American Dental... Dec 1968
Topics: Alginates; American Dental Association; Dental Impression Materials; Humans; United States
PubMed: 5246639
DOI: 10.14219/jada.archive.1968.0369 -
Dental Materials : Official Publication... May 2013A theoretical model, based on fluid dynamics, was developed to measure impression pressure. The purpose of this study was to evaluate the validity of this theoretical... (Comparative Study)
Comparative Study
OBJECTIVE
A theoretical model, based on fluid dynamics, was developed to measure impression pressure. The purpose of this study was to evaluate the validity of this theoretical model by comparing its theoretical analysis against actual pressure measurements conducted using an impression tray and edentulous oral mucosa analog embedded with pressure sensors.
METHODS
In the theoretical model, a hollow tube was mounted onto an impression tray by penetrating through the tray. When force was applied to the tray, pressure was produced which then caused the impression material to flow into the hollow tube. Length of impression material which flowed into tube was denoted as l. In the calculation formula for theoretical model, pressure impulse I was expressed as a function of impression flow length l. For actual pressure measurements, four electric pressure sensors were embedded in an experimental edentulous arch. To visually observe and measure length of impression material flow, four transparent silicon tubes were mounted vertically at different positions on tray. During tray seating, impression material flowed into tubes and pressure which caused material flow movement was measured by the embedded sensor at each tube's position.
RESULTS
Based on actual pressure measurements under one experimental condition, regression analysis of pressure data acquired from electric sensors yielded the formula, Y=0.056X²+0.124X. Based on theoretical analysis using a particular viscosity value, the numerical formula yielded was Y=0.057X², which resembled that of the regression formula.
SIGNIFICANCE
Theoretical model presented in this paper augured well for clinical application as an easy and economical means to examine magnitude and distribution of impression pressure by measuring lengths of impression material flow in tubes fixed to impression tray.
Topics: Dental Impression Materials; Dental Impression Technique; Denture, Complete; Models, Dental; Models, Theoretical; Pressure; Regression Analysis; Viscosity
PubMed: 23477950
DOI: 10.1016/j.dental.2013.02.005 -
Journal of Prosthodontics : Official... Sep 1992In the American National Standards Institute/American Dental Association specification no. 19, compatibility of impression materials with dental stones is assessed by... (Comparative Study)
Comparative Study
PURPOSE
In the American National Standards Institute/American Dental Association specification no. 19, compatibility of impression materials with dental stones is assessed by the presence of a 20-microns-wide line reproduced on an unmodified calcium sulfate dihydrate cast. In actual dental practice, modified type IV dental stones are used, although little is known of their compatibility with polysulfide impression materials. This study evaluated the compatibility of 6 polysulfide impression materials and 11 modified type IV dental stones.
MATERIALS AND METHODS
A line 20 microns wide was etched on four glass dies. Four samples of each combination of impression material and dental stone were prepared according to the manufacturer's directions with an additional 3 minutes for the final setting time. Compatibility was determined by the presence of the reproduced line on the dental stones, as observed under low angle 10 x magnification by four rater groups.
RESULTS
The line was reproduced on all of the impression specimens, and the examiners recorded 66 positive identifications of the line on the stone casts out of a possible 1,056 ratings for a total of 6.25% of the specimens. Out of a possible 66 impression-stone combinations, only 18 reproduced the 20-microns line. The combinations reproducing the lines most frequently (75%) were Neoplex with Blue Die Stone (Columbus Dental, St Louis, MO) and Coeflex with Indic Die Stone (Coe Lab Inc, Chicago, IL).
CONCLUSIONS
The study showed that many combinations of polysulfide impression materials and modified type IV dental stones did not reproduce the 20-microns line; therefore, not every polysulfide is compatible with every type IV dental stone.
Topics: Calcium Sulfate; Dental Impression Materials; Materials Testing; Sulfides
PubMed: 1308218
DOI: 10.1111/j.1532-849x.1992.tb00424.x -
Dental Assisting Jan 1985
Topics: Agar; Dental Impression Materials; Dental Impression Technique; Hot Temperature
PubMed: 3882262
DOI: No ID Found