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PeerJ 2022Dental impressions are used to record anatomy of teeth and surrounding oral structures. Impression materials become contaminated with saliva and blood requiring...
BACKGROUND
Dental impressions are used to record anatomy of teeth and surrounding oral structures. Impression materials become contaminated with saliva and blood requiring disinfection, which may have negative impact on dimensional stability of materials.
OBJECTIVE
Comparatively evaluate linear dimensional changes of synthesized Tetra-functional (dimethylsilyl) orthosilicate (TFDMOS) containing Polyvinylsiloxane (PVS) impressions following sodium hypochlorite disinfection.
METHODS
Percentage dimensional changes of three commercial PVS (Elite HD Monophase, Extrude and Aquasil Ultra Monophase) and five experimental PVS impression materials were measured. Experimental material contained novel cross-linking agent (TFDMOS) and a non-ionic surfactant (Rhodasurf CET-2) that is Exp-A (without TFDMOS), Exp-B (with TFDMOS), Exp-C (TFDMOS+ 2% Rhodasurf CET-2), Exp-D (TFDMOS+ 2.5% Rhodasurf CET-2) Exp-E (TFDMOS+ 3% Rhodasurf CET-2). Samples were made using rectangular stainless-steel molds (40 × 10 × 3 mm) and linear dimensional changes were measured using a calibrated travelling microscope at 10× magnification after immersion in distilled water (D.W) and 1% Sodium Hypochlorite solution at two different time intervals ., 30 min and 24 h.
RESULTS
Samples immersed in 1% NaOCl showed significant ( < 0.05) dimensional changes after 30 min of immersion. Exp-E showed significantly greater dimensional changes than their control (Exp-A and Exp-B). In distilled water, there were no significant difference among the tested materials. Aquasil exhibited highest expansion (0.06%) in both solutions. At 24 h, among the commercial materials, Extrude had the greatest expansion followed by Aquasil and Elite in DW while Aquasil showed the greatest expansion followed by Extrude and Elite in NaOCl.
CONCLUSION
Experimental PVS had linear dimensional changes within the ISO 4823; 2015 recommended range. However, extended immersion can negatively affect the linear dimensions.
Topics: Sodium Hypochlorite; Disinfection; Water
PubMed: 35174015
DOI: 10.7717/peerj.12812 -
Dental Materials : Official Publication... Jul 2012To study the role of the various components of alginate dental impression materials. (Comparative Study)
Comparative Study
OBJECTIVE
To study the role of the various components of alginate dental impression materials.
METHODS
Experimental materials were formulated and their physical properties characterized and compared to commercially available counterparts (Neocolloid, Palgat Plus and Blueprint Cremix). Properties examined were: dimensional stability and weight change in water and artificial saliva; setting behavior; Shore A hardness and tear energy. The role of magnesium oxide was also investigated.
RESULTS
Weight changes in water and artificial saliva can be attributed to an initial thermodynamic potential owing to the ionic content of the alginate, causing water to diffuse into the material. Water is then driven back out following a reversal of this potential. Hardness results for experimental materials were within the range obtained from the commercial materials. The hardness value for an experimental formulation that did not contain magnesium oxide was lower than values from the other experimental materials that did. Tear energies for all three experimental materials were greater than those of the commercial products. There were statistically significant differences between the two experimental materials that contained magnesium oxide and one that did not. With regard to setting time, statistically significant differences were seen between commercial materials and two of the experimental materials. The experimental material that did not contain magnesium oxide had a considerably longer setting time than all of the other materials tested.
SIGNIFICANCE
The key role of magnesium oxide in the setting reaction and the effect on hardness have been demonstrated and discussed.
Topics: Alginates; Chemistry, Physical; Dental Impression Materials; Hardness; Magnesium Oxide; Materials Testing
PubMed: 22575742
DOI: 10.1016/j.dental.2012.03.012 -
Journal of the Mechanical Behavior of... Jun 2023This study aimed to evaluate the effect of splinting material type and material location on the force resistance of splinted periodontally compromised teeth with...
This study aimed to evaluate the effect of splinting material type and material location on the force resistance of splinted periodontally compromised teeth with hypermobility. Extracted teeth including the target tooth (maxillary second premolar) and its adjacent teeth were placed into the alveolar sockets of a dental arch model via artificial periodontal ligaments made of elastic impression material. Three different experimental models with varied target tooth mobility including Periotest® values (PTVs) of 20, 30, and 40 were fabricated (named models #20, #30, and #40, respectively). For each experimental model, the force resistance of tooth splinting was tested using the following four materials: everStick PERIO (glass fiber reinforcement: GFR), FORESTAFLEX (braided stainless steel: BSS), Ortho-FlexTech (stainless steel chain: SSC), and Super-Bond (MMA-based resin cement: MRC). The evaluated measures were the PTV after tooth splinting and the required load to cause tooth displacements of 0.05 mm and 0.10 mm in the vertical and lateral directions, respectively. The splinting material type and material location as well as the original PTV of target the tooth significantly affected all the evaluated measures (p < 0.001). MRC revealed the significantly highest force resistance of tooth splinting regardless of material location in each experimental model and was followed by GFR. The PTVs of splinted teeth were comparable to those of adjacent anchor teeth in models #20 and #30 when using GFR, while that was comparable in model #40 when using MRC. Meanwhile, the load causing certain tooth displacement showed a similar tendency to previous-reported data with healthy teeth in model #20 when using GFR, while that showed a similar tendency in models #30 and #40 when using MRC. Overall results concluded that splinting material type and location play a role in the resistance against the deflection force of splinted periodontally compromised hypermobile tooth. It was noted that MRC provided the highest resistance against the deflection force of splinted teeth regardless of material location whereas GFR maintained the physiologically considered tooth mobility.
Topics: Humans; Tooth Mobility; Stainless Steel; Periodontal Ligament; Bicuspid
PubMed: 37119722
DOI: 10.1016/j.jmbbm.2023.105873 -
Journal of Medicine and Life 2019The need to use a natural alternative for disinfecting dental impression materials, which should be biocompatible and effective, led us to evaluate the efficacy of Aloe...
Evaluation of efficacy of Aloe Vera as a Disinfectant by Immersion and Spray methods on Irreversible Hydrocolloid Impression Material and its Effect on the Dimensional Stability of Resultant Gypsum Cast - An in Vitro Study.
The need to use a natural alternative for disinfecting dental impression materials, which should be biocompatible and effective, led us to evaluate the efficacy of Aloe vera as a disinfectant by immersion and spray method on alginate impression material and its effect on the dimensional stability of the resultant gypsum cast. The efficacy of the disinfection procedures against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans was evaluated by determining the number of colony-forming units (CFU) recovered after disinfection of alginate discs inoculated with 1x106 CFU for defined intervals with aloe vera solution (99.96%). Dimensional stability was determined from the mean percentage deviation of three measurements that were taken between the fixed points on the casts using a traveling microscope and compared with corresponding measurements from the master model and controls. Statistical analysis of data was determined by analysis of variance. We found out that there is a mean percentage reduction in colony count of S. aureus, P. aeruginosa, and C. albicans after 3 minutes of immersion in aloe vera and after 3 minutes spray disinfection. Complete elimination of all the microorganism cells after 7 min immersion and spray disinfection. There was a statistically significant difference in the increase of the mean anteroposterior (AP) and cross arch (CA) dimension after 3 and 7 minutes immersion in aloe vera. Spraying with aloe vera for 7 minutes was proved to be the most effective disinfection procedure without altering dimensional stability.
Topics: Alginates; Aloe; Anti-Infective Agents; Bacteria; Calcium Sulfate; Colloids; Colony Count, Microbial; Dental Impression Materials; Disinfectants; Disinfection; Fungi; Microbial Sensitivity Tests
PubMed: 32025258
DOI: 10.25122/jml-2019-0050 -
BMC Oral Health Nov 2020Fixed prosthodontics require an accurate impression for the teeth and the area to be restored for the laboratory to fabricate the desired restoration without mistakes....
BACKGROUND
Fixed prosthodontics require an accurate impression for the teeth and the area to be restored for the laboratory to fabricate the desired restoration without mistakes. This study evaluated the quality of impressions received by private laboratories for the fabrication of fixed prosthesis by describing the frequency of clinically detectable errors and by analyzing association between the various factors involved.
METHODS
165 impressions were collected from four dental laboratories. Jaw involved, type of tray, size of tray, number of prepared units, type of impression materials, techniques and viscosity in case of elastomeric impressions and type of prosthesis requested were recorded. Data referring to errors and visible defects including errors in finish line, in preparation area, in silicone impression technique and blood in impression were also documented. Factors affecting errors present were also assessed. Association between dentist gender and experience years and impression errors was assessed. Chi square and Fisher exact tests used to examine the association between categorical variables and outcomes.
RESULTS
The total of error considering not immediately pouring as an error. Alginate was the most impression used. of impressions evaluated (50.9%), 97% were have at least one visible error; 92.1% had errors in finish line, 53.9% had errors in preparation area and (72.8%) of elastomeric impressions were have at least one error in technique. Blood in impression was detected in 52.1% of impressions. Significant association was found between material type and errors in finishing line and preparation area. Significant relationships were found between gender and errors in silicone impression technique (p < 0.05).
CONCLUSION
Within the limitations of this study, high frequency of detectable errors was found in fixed prosthesis impressions received by private dental laboratories. This high frequency is of serious concern, as this will result in poor fitted fixed prosthesis provided to patients.
Topics: Dental Implants; Dental Impression Materials; Dental Impression Technique; Humans; Laboratories; Models, Dental; Yemen
PubMed: 33148226
DOI: 10.1186/s12903-020-01294-1 -
International Journal of Dentistry 2021The dimensional accuracy of casts is essential in the quality of fixed prosthesis treatment, whereby the impression method is a very crucial factor affecting it. The aim...
Comparing the Dimensional Accuracy of Casts Obtained from Two Types of Silicone Impression Materials in Different Impression Techniques and Frequent Times of Cast Preparation.
INTRODUCTION
The dimensional accuracy of casts is essential in the quality of fixed prosthesis treatment, whereby the impression method is a very crucial factor affecting it. The aim of this in vitro study is to compare the dimensional accuracy of casts resulting from two types of silicone impression materials in different impression techniques and frequent times of cast preparation.
MATERIALS AND METHODS
A metal model was made from two prepared abutments, and 10 casts were prepared from each material technique ( = 40). The impressions were made by condensation and addition silicone (one-stage and two-stage impressions). The casts were made from same impressions 1 h, 24 h, and 14 days. The diameter, height, and the distance between two dies were recorded. Data were analyzed by repeated measure ANOVA ( value <0.05).
RESULTS
The dimensional accuracy of all four materials techniques of impression (diameter, height, and the distance between dies) was the same in different times of impression. Dimensional accuracy of the die diameter and distance between dies in one-stage (Speedex) condensation silicon and one-stage (Panasil) addition silicone did not differ significantly, and their one-stage method developed more accurate casts compared to the two-stage method of the same impression material. The height of the casts prepared from the one-stage method through Speedex and Panasil did not differ significantly from the two-stage method of the same impression material.
CONCLUSION
One-stage condensation silicone and one-stage addition silicone material techniques offered the maximum dimensional accuracy in the obtained casts. The time of impression did not have any significant effect in the accuracy of any of the four impression material techniques.
PubMed: 34616455
DOI: 10.1155/2021/9977478 -
Journal of Oral and Maxillofacial... 2021Dental identification plays a major role in mass disaster identification of human remains. Palatal rugae can be used as a substitute for a comparative method of...
BACKGROUND
Dental identification plays a major role in mass disaster identification of human remains. Palatal rugae can be used as a substitute for a comparative method of identification.
MATERIALS AND METHODS
The present cross-sectional study was done with 137 pre- and post-orthodontically treated casts of patients, which were divided into 50 cases each of extraction and nonextraction and 37 cases of palatal expansion involving both extraction and nonextraction. Hydrocolloid (alginate) impression of the upper jaw of the patient was taken and then cast in the dental plaster of Paris material. Palatal rugae pattern was classified according to Lysellm, and Thomas and Kotze classification. Two Observers recorded the data, mean of two were taken for analysis.
RESULTS
On the right side, there was no significant difference between the extraction and nonextraction groups; however, there was a rise in length in the nonextraction and palatal expansion groups. On the left side, there was little change between the nonextraction and palatal expansion groups, but the extraction group had a modest increase in length. Mean lengths compared within three groups revealed insignificant difference.
CONCLUSION
Palatal rugae pattern can be used in establishing identity in forensic medicine provided antemortem data are available. Orthodontic treatment has an impact on stability of palatal rugae. Most reliable and stable points being third rugae, they could be used as reference points to evaluate tooth movements.
PubMed: 35281156
DOI: 10.4103/jomfp.jomfp_269_21 -
European Journal of Breast Health Jul 2020This study compares standard commercial bolus material (Superflab) to custom prepared silicone dental impression material (CDIM) and play dough material (PDM) with...
OBJECTIVE
This study compares standard commercial bolus material (Superflab) to custom prepared silicone dental impression material (CDIM) and play dough material (PDM) with respect to dosimetric properties and applicability by using ion chamber measurement and calculated dose values.
MATERIALS AND METHODS
The CDIM bolus was prepared by mixing dental impression silicone material with enough water to maintain a density of about 1.0 g/cm. The prepared bolus material is applied on an RW3 solid phantom by covering 10x10 cm area with 0.5-1 cm thickness. Ion chamber measurements were performed separately with and without bolus material application. The setup was scanned in CT and the same procedure was repeated in the TPS using the scan data, in which the Pencil Beam Convolution dose calculation algorithm was used. To compare the effect of bolus material on tissue, the Superflab bolus and CDIM bolus were applied with 1 cm of thickness on postmastectomy scar and dose calculations on TPS were performed.
RESULTS
After comparison of the dosimetric values for Superflab, CDIM and PDM, we obtained statistically meaningful results between superflab and CDIM. For PDM, the results obtained with TPS and ion chamber measurements indicated that, it is not suitable to use in radiotherapy application due to its material properties. For the simulated skin dose values obtained at five random points on the scar tissue, the comparison of Superflab and CDIM TPS calculation results were not statistically significant.
CONCLUSION
The CDIM is easy to prepare and apply on irregular mastectomy scar tissue and it prevents formation of air gaps in the application surface. Especially for curved anatomical regions such as scar tissue, inclusion of the bolus material in treatment planning protocol will reduce dose uncertainty in application. It is safe to use CDIM as an alternative to Superflab in radiotherapy application, whereas PDM is not useful in clinical practice due to its material properties.
PubMed: 32656515
DOI: 10.5152/ejbh.2020.5041 -
Journal of Dentistry Jul 2023To assess the influence of different restorative materials and surface wetness on intraoral scanning accuracy.
OBJECTIVES
To assess the influence of different restorative materials and surface wetness on intraoral scanning accuracy.
METHODS
Reference casts with an extracted second premolar and first and second molar were digitized (L2). Four groups were established according to the material of the first molar: natural tooth (control), zirconia (Z), lithium disilicate (LD), and nanoceramic resin crown (NC). Four subgroups were developed: dry, low-, mild-, and high-wetness subgroups (n = 15). All the scans were completed by using an intraoral scanner (TRIOS 3). In the control-dry subgroup, the reference cast was dry. In the control-low subgroup, artificial saliva was sprayed with a 1 mL/min volumetric flow for 4 s. In the control-mild and control-high subgroups, the same procedures as in the control-low subgroup were performed, but with a volumetric flow of 4 and of 8 mL/min, respectively. In the Z, LD and NC groups, each crown was fabricated with its respective material. Trueness was analyzed using 2-way ANOVA and Bonferroni tests. The Levene and Bonferroni tests were used to assess precision (α = 0.05).
RESULTS
Material (P < .001) and wetness (P < .001) significantly influenced trueness and precision. The mild and high subgroups revealed lower trueness and precision compared with the dry and low subgroups. The control, Z, and LD groups under dry and low wetness conditions showed better trueness compared with the NC group, but the materials tested had no significant precision discrepancies. Under mild wetness conditions, all the materials showed no significant trueness discrepancies. Under high wetness conditions, the LD group demonstrated the best trueness and precision.
CONCLUSIONS
The restorative materials and surface wetness tested influenced scanning trueness and precision of the IOS assessed.
CLINICAL SIGNIFICANCE
Dried surfaces are recommended to maximize the scanning accuracy values of the IOS tested. Overall, the presence of saliva and dental restorations can reduce the performance of the IOS tested.
Topics: Imaging, Three-Dimensional; Dental Impression Technique; Models, Dental; Computer-Aided Design; Dental Materials
PubMed: 37061118
DOI: 10.1016/j.jdent.2023.104521 -
Journal of Clinical and Experimental... Feb 2018Precision of implant impressions is a prerequisite for long-term success of implant supported prostheses. Impression materials and impression techniques are two...
BACKGROUND
Precision of implant impressions is a prerequisite for long-term success of implant supported prostheses. Impression materials and impression techniques are two important factors that impression precision relies on.
MATERIAL AND METHODS
A model of edentulous maxilla containing four implants inserted by All-on-4 guide was constructed. Seventy two impressions using polyether (PE), polyvinyl siloxane (PVS), and vinyl siloxanether (VSE) materials with direct and indirect techniques were made (n=12). Coordinates of implants in casts were measured using coordinate measuring machine (CMM). Data were analyzed with ANOVA; t-test and Tukey test were used for post hoc.
RESULTS
With two-way ANOVA, mean values of linear displacements of implants were significantly different among materials and techniques. One-way ANOVA and Tukey showed significant difference between PE and VSE (=0.019), PE and PVS (=0.002) in direct technique, and between PVS and PE (<0.001), PVS and VSE (<0.001) in indirect technique. One-way ANOVA and t-test showed significant difference between the two techniques in PVS groups (<0.001) and in PE groups (=0.02). Two-way ANOVA showed mean values of rotational displacement of implants were significantly different among materials. One-way ANOVA and Tukey test showed significant difference between PVS and PE (=0.001) and between PVS and VSE (=0.012) in indirect groups.
CONCLUSIONS
On the basis of the results, when deciding on the material to make an impression of implants, PE is recommended for direct technique while PE and VSE are recommended for indirect technique. Recommended technique for VSE is either direct or indirect; and for PE and PVS is direct. Polyvinyl siloxane, polyether, vinyl siloxanether, direct technique, indirect technique, All-on-4, coordinate measuring machine.
PubMed: 29670733
DOI: 10.4317/jced.54457