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European Journal of Dentistry May 2022The aim of this study was to evaluate and compare penetration ability and tensile strength among vinylsiloxanether (VSE), polyether (PE), and polyvinylsiloxane (PVS)...
OBJECTIVES
The aim of this study was to evaluate and compare penetration ability and tensile strength among vinylsiloxanether (VSE), polyether (PE), and polyvinylsiloxane (PVS) elastomeric dental impression materials.
MATERIALS AND METHODS
The models were constructed for penetration ability test by simulated gingival sulcus width and moist environment. The 0.05, 0.1, and 0.2 mm of simulated gingival sulcus widths were used. Each simulated gingival sulcus width was impressed 10 repeats per one elastomeric impression material. All extension of elastomeric dental impression materials was scaled by Measuring Microscope (MM-11; Nikon, Tokyo, Japan). On the issue of the tensile strength study, the models were constructed following type 1 of the ISO 37:2017 specifications and/or type C of ASTM.D412 specifications. The two-way analysis of variance (ANOVA) and Tukey's honest significant difference test were performed in the penetration ability test. The one-way ANOVA and Dunnett's T3 test were performed in the tensile strength test. The significance level was set at 0.05.
RESULTS
PE showed the best extension into all widths of simulated sulcus followed by VSE and PVS, respectively. PVS was significantly higher in tensile strength than VSE and PE, while VSE was significantly higher than PE.
CONCLUSION
Penetration ability of elastomeric dental impression materials was depended on gingival sulcus width. The wider the sulcular width, the better the penetration ability of elastomeric dental impression materials. PE presented the best penetration ability, while the novel PVS showed highest tensile strength.
PubMed: 34852393
DOI: 10.1055/s-0041-1735793 -
Cureus Sep 2022Introduction The current gold standard is a conventional impression made with various impression materials and trays and results in a gypsum cast. With the development...
Introduction The current gold standard is a conventional impression made with various impression materials and trays and results in a gypsum cast. With the development of milling and printing materials in dentistry, especially zirconia, a digital model has become increasingly important. Objectives To compare the accuracy of the conventional impression scan (CIS), gypsum cast scan (GCS), and digital impression scan (DIS) to obtain a full-arch digital model. Materials and methods A resin reference cast was fabricated. It was scanned by an extra-oral scanner to measure its accuracy as a reference scanner. Eight conventional impressions of the reference cast were taken by polyvinyl siloxane and scanned. After that, they were poured with type IV dental stones and scanned too. The reference cast was scanned by an intraoral scanner eight separate times. Digital models within each group were superimposed individually to measure precision. In addition, each model from each group was superimposed on one model from the reference scanner precision group to measure trueness. Results The reference scanner showed the highest accuracy among groups with a precision of 1.5±0.8 µm and a trueness of 5.5±1.9 µm (P<0.006), while precision values of gypsum cast were 8.1±1.7 µm and trueness values were 9.3±2.6 µm (P<0.012). Conventional impressions showed a precision of 14.06±2.01 µm and a trueness of 16.15±2.07 µm (P<0.012). Digital impressions were the least accurate among the groups, as precision values were 38.22±15.23 μm and trueness values were 35.19±8.7 μm (P<0.006). Conclusion The gypsum cast scans showed the highest accuracy, followed by the conventional impression scans, and finally the digital impression scans, with no clinical significance.
PubMed: 36249650
DOI: 10.7759/cureus.29055 -
Journal of Medicine and Life May 2023This study aimed to examine the effect of inter-dental abutment distance on the accuracy of digital and conventional impression methods. Five maxillary and mandibular...
This study aimed to examine the effect of inter-dental abutment distance on the accuracy of digital and conventional impression methods. Five maxillary and mandibular models were prepared with different inter-dental abutment distances. Digital scans were obtained using an extraoral laboratory scanner as reference data. Each group was scanned 8 times using the intra-oral scanner for the digital method. For the conventional impression method, 8 additional silicone impression material was used to generate the stone casts from each group. Then casts were scanned. In the next step, stereolithography (STL) data was exported from the scans. The STL files were super-imposed on the reference scans using 3shape dental designer software to make the measurement. Kolmogorov-Smirnoff was used to determine if the data were normally distributed. In the digital impression method, as the abutment distance increased, the accuracy decreased. Various inter-dental abutment distances in digital groups showed significant differences (p=0.016) in impression accuracy, while the difference among conventional groups was not statistically significant (p=0.822). In the digital method, the mean inter-dental abutment between the 4-5 and 3-7 groups, 4-6 and 3-7 groups had a significant difference (p<0.05). However, the conventional method revealed no significant differences (p>0.05) between groups. In conclusion, when the inter-dental abutment distance exists and is surrounded by soft tissue, the possibility of error in the digital impression method is higher than in the conventional impression method.
Topics: Humans; Dental Abutments; Models, Dental; Computer-Aided Design; Mandible; Maxilla; Imaging, Three-Dimensional; Dental Impression Technique
PubMed: 37520485
DOI: 10.25122/jml-2023-0103 -
Journal of Orofacial Orthopedics =... Nov 2020This study investigates the accuracy of abutment transfer with current impression materials and provides a concise overview, including other relevant factors, in order...
PURPOSE
This study investigates the accuracy of abutment transfer with current impression materials and provides a concise overview, including other relevant factors, in order to enable clinicians to make an informed decision about the optimal impression for this treatment procedure.
METHODS
In all, 96 impressions of a cadaver head with two orthodontic miniscrews in place were taken with four common impression materials by two observers and using two methods of application. After pouring with a standard type IV stone and abutment transfer, all models and the upper jaw (which had been separated from the head) were scanned in a standard model scanner (Zirkonzahn® [Zirkohnzahn GmbH, Gais, Italy] S600 ARTI) and evaluated using a computer-aided design (CAD) program (GOM-Inspect [Gesellschaft für optische Messtechnik m.b.H., Braunschweig, Germany]). The deviations were measured at six points per screw and statistically evaluated with SPSS® (IBM, Chicago, IL, USA).
RESULTS
Optimal values were obtained with biphasic polyvinylsiloxane, while monophasic polyvinylsiloxane, alginate and polyether also resulted in acceptable accuracy. Observer experience showed no effect and the method of application had only a minor effect on accuracy.
CONCLUSIONS
Within the limitations of this study, it seems that all impression materials are suitable for miniscrew abutment transfer, provided that methods of intraoral adaptation of the orthodontic appliance can be employed. If higher accuracy is needed or for clinicians with less experienced, a biphasic polyvinylsiloxane impression with the putty-wash technique should be used as this combination reduces setting time. The most cost-effective version, alginate, can be used if the consequences of greater deviations can be handled. Caution is advised with polyether if undercuts are present.
Topics: Dental Impression Materials; Dental Impression Technique; Germany; Italy; Models, Dental
PubMed: 32897413
DOI: 10.1007/s00056-020-00245-3 -
Minerva Dental and Oral Science Feb 2023The success in acquiring a precision impression in the dental field is a compromise between the processing time and the setting time of the impression material. A device...
BACKGROUND
The success in acquiring a precision impression in the dental field is a compromise between the processing time and the setting time of the impression material. A device called "Impression Heater" (EU application n° EP20186042.6) has recently been patented, which consists of a self-heating disposable adhesive patch with an exothermic chemical reaction to be placed on the dental impression tray. The aim of the study was to evaluate the effectiveness of a thermal impression accelerator in reducing the setting time of different elastomers.
METHODS
Three samples of 5 different elastomeric materials (width 6 mm x length 50 mm x depth 3-5-7 mm) the hardening of the material was evaluated at intervals of 15 seconds using an ASTM 2240 Shore-A durometer at 20 °C. The same procedure was replicated 3 times after positioning on a Impression Heater at temperatures of 35 °C, 50 °C and 65 °C, for each material.
RESULTS
An increase in the impression material temperature from 35 °C to 50 °C reduces the setting time of an amount between 38.1% and 45.8%. Increasing the temperature from 35 °C to 65 °C results in a reduction of the setting time between 52.4% and 66.9%. At higher temperatures, the greater thickness of the impression material requires longer hardening times.
CONCLUSIONS
The tests carried out confirm the validity of the patented idea which reduces the time of impression taking while keeping the working time sufficiently long for the operator to manoeuvre.
Topics: Dental Impression Technique; Dental Impression Materials; Elastomers; Elasticity; Time Factors
PubMed: 36197277
DOI: 10.23736/S2724-6329.22.04676-9 -
Journal of Biotechnology Dec 2022Algae are effective predecessors of nutrient foods and preventive drugs, gaining global attraction in recent years. It exhibits potent antiviral, antibacterial,... (Review)
Review
Algae are effective predecessors of nutrient foods and preventive drugs, gaining global attraction in recent years. It exhibits potent antiviral, antibacterial, antifungal, anti-inflammatory, antioxidant, anti-glycemic, and cholesterol-lowering properties due to their richness in highly valuable secondary metabolites. Nevertheless, algae produce valuable bioproducts, its application in dentistry is in its primitive stage. This review focuses on the emergence and emerging role of micro/macroalgae as a natural source of therapeutic, preventive, and biocompatible agents in dentistry. Several studies unveiled that Cyanobacteria, Spirulina, and Chlorella species offer high oral antibacterial and antifungal properties compared to gold standard agents. The characteristic of algae to scavenge superoxide and hydroxyl free radicals, fabricate them as an anti-oxidative and anti-cancer agent. Either alone or by synergism with pinnacle therapies they are found to produce promising curative actions against periodontitis by embattling proinflammatory cytokines. Technologies extend the functions of microalgae as a detoxifying agent, potent drug delivery system, and adjunct regenerative material in chronic periodontitis. Its application as thickening, binding, anticariogenic agent in toothpaste, antibacterial agent in mouthwash, and biocompatible agent in dental impression materials remains very primitive. Low-cost and eco-friendly technologies are needed for the production of oral hygiene products using algal biomass.
Topics: Chlorella
PubMed: 36195207
DOI: 10.1016/j.jbiotec.2022.09.021 -
The International Journal of Oral &... 2022The purpose of this study was to evaluate the impression accuracy of two implants placed in different orientations and compare the impression accuracy obtained with the...
PURPOSE
The purpose of this study was to evaluate the impression accuracy of two implants placed in different orientations and compare the impression accuracy obtained with the dual-arch impression technique using hybrid impression copings and the conventional open-tray impression technique.
MATERIALS AND METHODS
Five mandibular dentiform models were prepared by placing implants in the second premolar and second molar regions in the following different orientations: parallel to each other; 15-degree mesiodistal angulation; 30-degree mesiodistal angulation; 15-degree buccolingual angulation; and 30-degree buccolingual angulation. After making 10 impressions for each model with the open-tray impression technique and dual-arch impression technique with hybrid impression copings, cast models were fabricated for each impression (n = 10). Scan bodies were mounted on the five dentiform models and the fabricated 100 cast models were scanned using a desktop scanner. The three-dimensional deviation of the scan bodies on the cast models was calculated and compared to the reference data from the dentiform models. A two-way analysis of variance was conducted (α = .05).
RESULTS
The root mean square deviation values obtained from the implants placed with 30-degree mesiodistal angulation were 93.05 ± 6.21 μm with the open-tray impression technique and 104.01 ± 8.89 μm with the dual-arch impression technique, which were the largest deviation values for both techniques (P < .001). Compared to the open-tray impression technique, the dual-arch impression technique with the hybrid impression copings showed significantly lower accuracy when the angulation between the implants was 15 degrees mesiodistally (P < .001), 30 degrees mesiodistally (P = .016), or 30 degrees buccolingually (P < .001). However, there was no significant difference between the accuracy of the two impression techniques for parallel implants (P = .74).
CONCLUSION
When the two implants were inclined 30 degrees mesiodistally, both implant impression techniques showed the largest deviation and the dual-arch impression technique showed lower accuracy compared to the conventional open-tray impression technique. Parallel placement of implants may improve impression accuracy and enable use of the dual-arch impression technique.
Topics: Dental Implants; Dental Impression Materials; Dental Impression Technique; Models, Dental
PubMed: 36170315
DOI: 10.11607/jomi.9441 -
Journal of Prosthodontics : Official... Sep 2023Preliminary impressions must record the periphery and height of maxillary defects to allow for an eventual extension of the master impression tray. These impressions are...
Preliminary impressions must record the periphery and height of maxillary defects to allow for an eventual extension of the master impression tray. These impressions are usually made with irreversible hydrocolloid. Carrying the impression material into the defect can be complex, especially in the case of a limited oral opening. Moreover, the patient can be harmed during the removal procedure, and material may be stuck in anatomical structures. The technique presented in this article avoids these issues in any maxillary defect with a two-step preliminary impression. An elastomeric material ball is first placed in the defect until full setting. Then, this "obturator bulb" is removed and eventually relined until it is retentive. Retentions are designed on the oral side of the bulb and the bulb is placed back into the defect. Finally, an alginate over-impression of the maxillary is made. The alginate is removed after full setting, and the obturator can be reassembled on the maxillary impression to provide a full recording of the maxillary. This protocol can safely be used for defects of any size, despite eventual limitations in oral opening.
PubMed: 37691235
DOI: 10.1111/jopr.13766 -
Prague Medical Report 2023The objective of this article is to concisely review the main clinical techniques used to make the functional impression to manufacture a removable partial denture.... (Review)
Review
The objective of this article is to concisely review the main clinical techniques used to make the functional impression to manufacture a removable partial denture. Through this review, the dentist can develop his clinical knowledge.
Topics: Humans; Denture, Partial, Removable
PubMed: 38069644
DOI: 10.14712/23362936.2023.29 -
Dental Research Journal 2019Self-disinfecting impression materials would reduce time and energy needed for impression disinfecting process in clinic. The aim of this study was to evaluate the...
BACKGROUND
Self-disinfecting impression materials would reduce time and energy needed for impression disinfecting process in clinic. The aim of this study was to evaluate the antimicrobial effect of alginate mixed with nanosilver solution at a concentration of 500 ppm and 1000 ppm on common oral microorganisms and assess changes in working time, setting time, and surface detail reproduction.
MATERIALS AND METHODS
In this study, three groups were assigned. The first group was alginate, the second group was alginate mixed with 500 ppm nanosilver, and the third group was alginate mixed with 1000 ppm nanosilver. Antimicrobial effect on , , and was studied using direct contact test in each group ( = 10). Working time ( = 10), setting time ( = 10), and surface detail reproduction ( = 10) were evaluated separately using the ISO 21563 protocol. Descriptive tables were used to describe the data. Kruskal-Wallis test used to determine significant differences in the number of colonies was counted in antimicrobial test (α = 0.05).
RESULTS
No adverse effects observed in working time, setting time, and surface detail reproduction of alginate impressions. Alginate mixed with silver nanoparticles showed no inhibitory effect on and , but the number of colonies were counted in the group 1000 ppm was significantly lower than 500 ppm ( = 0.001).
CONCLUSION
Antimicrobial effect of alginate mixed with silver nanoparticles is not clinically indicated. Nevertheless, its physical features did not change significantly.
PubMed: 31803382
DOI: No ID Found