-
Journal of Pharmacy & Bioallied Sciences Jul 2023The current study examined the accuracy of casts generated using direct impression processes with and without splints for multiple dental implants utilizing two...
A Comparative Study to Assess Accuracy of Casts Prepared using Direct Impression Technique with and without Splinting of Multiple Dental Implants Utilising Two Different Splinting and Impression Materials.
BACKGROUND
The current study examined the accuracy of casts generated using direct impression processes with and without splints for multiple dental implants utilizing two different splinting materials and impression materials.
MATERIALS AND METHODS
Dental replacement base intensity alleviating acrylic tar was used to create a reference model of a mandible with four inserts (Uniti, Equinox, D-3.7 mm, and L-13 mm) in the front. Polyether and polyvinyle siloxane impression materials were used to make impressions of the reference model utilizing direct non-splinted and splinted techniques.
RESULTS
Polyether impression material was found to produce more accurate impressions than polyvinyl siloxane, and impressions made using transfer copings splinted with pattern resins were found to be more accurate than those made using either unsplinted copings or copings splinted with light-cured wax resin.
CONCLUSIONS
All six impression techniques resulted in casts that were different from the reference model. Next, the polyether-splinted (SPR) technique is the nonsplinted technique employing polyether and polyvinyle siloxane imprint materials, and then, the splinted techniques using polyether and polyvinyle siloxane and produced the most accurate casts in comparison with the reference model.
PubMed: 37694030
DOI: 10.4103/jpbs.jpbs_271_23 -
Journal of Indian Prosthodontic Society 2016The purpose of this impression technique is to overcome the problem associated with restricted mouth opening in association with high arched palate by employing...
PURPOSE
The purpose of this impression technique is to overcome the problem associated with restricted mouth opening in association with high arched palate by employing pneumatic impression technique using latex balloon.
METHODS
A stock tray was modified with auto polymerizing acrylic resin. On the modified tray, a latex balloon was attached with aid of cyanoacrylate. The outlet of the balloon was then connected to a clinical sphygmomanometer bulb with the rubber pipe for air passage which would aid in inflating the balloon. The prepared tray assembly was then equipped for recording the impression. An adequate amount of addition polysiloxane impression material, sufficient to cover the entire area of the balloon was loaded onto the tray. The balloon was then inflated with the help of a sphygmomanometer bulb which transferred the air only in one direction. On completion of setting time of the impression material, the air pressure was relieved by deflating of balloon which helped in the easy removal of the impression. The impression was subsequently removed from the oral cavity and disinfected.
CONCLUSION
This novel technique was helpful for recording impression in patients presenting with restricted mouth opening and high arched palate.
PubMed: 27621555
DOI: 10.4103/0972-4052.186401 -
European Journal of Dentistry Oct 2023The aim of this study was to determine the effect of finish lines on the penetration ability of polyether and polyvinyl siloxane impression material into the...
OBJECTIVE
The aim of this study was to determine the effect of finish lines on the penetration ability of polyether and polyvinyl siloxane impression material into the simulated gingival sulcus.
MATERIALS AND METHODS
Three types of finish line (chamfer, deep chamfer, and radial shoulder) were impressed with two types of elastomeric impression material (polyether and polyvinyl siloxane) using a two-step impression technique. Ten samples of each finish line were prepared and then separated into two groups of impression material: polyether and polyvinyl siloxane. The model of the simulated gingival sulcus had a width of 0.1 mm and a depth of 3.5 mm with a subgingival finish line of 0.5 mm. The effect of the finish lines on the penetration ability of these impression materials was analyzed using a two-way analysis of variance (ANOVA) and Tukey's multiple comparison tests at a statistically significant level of 0.05.
RESULTS
A two-way ANOVA revealed a significant difference among finish lines, impression materials, and their interaction. The deep chamfer and radial shoulder finish lines displayed significantly higher penetration ability than the chamfer finish line. Moreover, polyether revealed significantly higher penetration ability than polyvinyl siloxane.
CONCLUSION
The finish lines affected the penetration ability of the impression materials. Therefore, the simulated gingival sulcus model demonstrates that it is an effective way of examining impression materials' penetration abilities.
PubMed: 36599449
DOI: 10.1055/s-0042-1759697 -
The Journal of Advanced Prosthodontics Aug 2021The purpose of this study was to compare the accuracy of three intraoral scanner (IOS) systems with three different dental arch widths.
PURPOSE
The purpose of this study was to compare the accuracy of three intraoral scanner (IOS) systems with three different dental arch widths.
MATERIALS AND METHODS
Three dental models with different intermolar widths (small, medium, and large) were attached to metal bars of different lengths (30, 40, and 50 mm). The bars were measured with a coordinate measuring machine and used as references. Three IOSs were compared: TRIOS 3 (TRI), True Definition (TD), and Dental Wings (DW). The relative length and angular deviation of both ends of the metal bars from the scan data set (n = 15) were calculated and analyzed.
RESULTS
Comparing among scanners in terms of trueness, the relative length deviation of DW in the small (1.28%) and medium (1.08%) arches were significantly higher than TRI (0.46% and 0.48%) and TD (0.33% and 0.18%). The angular deviation of DW in the small (1.75°) and medium (1.83°) arches were also significantly greater than TRI (0.63° and 0.40°) and TD (0.55° and 0.89°). Comparing within scanner, the large arch of DW showed better accuracy than other arch sizes ( < .05). On the other hand, the larger arch of TD presented a greater tendency of angular deviation in terms of trueness. No significant differences were found in terms of trueness between the arch widths of TRI group.
CONCLUSION
The different widths of the dental arches can affect the accuracy of some intraoral scanners in full arch scan.
PubMed: 34504672
DOI: 10.4047/jap.2021.13.4.205 -
Journal of Indian Prosthodontic Society 2023The aim of this study was to evaluate and compare the accuracy of hexed and nonhexed pickup impression copings with and without splinting using polyether (PE) and...
Comparison of accuracy of hexed and nonhexed pickup impression copings in a multiple variable impression setup for recording multiple straight and angulated implant positions: An study.
AIM
The aim of this study was to evaluate and compare the accuracy of hexed and nonhexed pickup impression copings with and without splinting using polyether (PE) and polyvinyl siloxane (PVS) impression materials in open-tray technique in recording multiple straight and angulated implant positions.
SETTINGS AND DESIGN
An accurate impression results in an accurate definitive cast, thus minimizing the incidence of prosthesis misfit. The critical aspect is to record the three-dimensional location of the implant in bone rather than reproducing fine surface details. Precise fit of a fixed implant-supported prosthesis depends on the accuracy of the implant analog location within the definitive cast. Factors which affect impression accuracy include implant angulation, impression material, impression copings, technique, and splinting.
MATERIALS AND METHODS
A sample size of 80 study models fabricated from the impression of different groups was included. A reference master model based on All-on-4 implant concept with two parallel (implants 1 and 2) and two angulated (implant 3 at 17° and implant 4 at 30°) was fabricated using implant angulation guide. All impressions were recorded using open-tray impression technique. The groups were divided into two main groups of 40 samples each. Group A used hexed open-tray impression copings and Group B used nonhexed open-tray impression copings. Both the groups involved impression recording using splinted (Subgroup I) and nonsplinted impression copings (Subgroup II). Further, impressions in each subgroup were made using PE (Subsubgroups a) and PVS (Subsubgroup b). A total of eight subsubgroups with ten samples each were included. Impressions were recorded for each group and poured into Type IV die stone for fabrication of study models. After 24 h, the study models and reference master model were fitted with implant abutments for measurement with coordinate measuring machine.
STATISTICAL ANALYSIS USED
The mean differences of the interimplant distance R1 (1-2), R2 (1-3), R3 (2-4), and R4 (3-4) between the reference model and sample models in different subsubgroups were calculated and three-way analysis of variance test was applied with Tukey's post hoc tests.
RESULTS
No significant difference was found in mean coronal deviations for distance R1, R2, and R3 (P > 0.05) between different study groups. P = 0.02 for R4 (distance between 17° and 30° implants) between impression materials subsubgroups suggested that significantly less distortion was created in location of highly angulated implants (>30°) using PVS impression material. Splinting and type of coping did not have a significant influence on impression accuracy. Increasing angulation decreased the accuracy.
CONCLUSION
PVS was found equivalent in accuracy to rigid PE for recording parallel or angulated implants. Impressions of implants with higher angulations were recorded more accurately with PVS. The study found no difference in accuracy with or without splinting. Furthermore, nonhexed impression copings facilitate easier and accurate recording of multiple angulated implant location in bone.
Topics: Dental Implants; Dental Impression Technique; Models, Dental; Dental Impression Materials
PubMed: 36588371
DOI: 10.4103/jips.jips_218_22 -
Journal of Clinical and Experimental... May 2021Several impression techniques, especially in combination with computer-aided design and computer-aided manufacturing (CAD/CAM), are used in increasing the accuracy of...
BACKGROUND
Several impression techniques, especially in combination with computer-aided design and computer-aided manufacturing (CAD/CAM), are used in increasing the accuracy of dental implantology and decreasing patient discomfort. The study was designed to examine the accuracy of the digital impression (DI) of multiple implants with an intraoral scanner (IOS) and compared with that of a conventional impression (CI).
MATERIAL AND METHODS
Four dental implants were placed in teeth area #33, #36, #43 and 46# of the mandibular full-arch model. The implanted model was replicated by IOS and CI after fitting of scannable abutments over the implant screws. Then, a small hole was made on the scan region (as a reference point). Two types of CI techniques were used; dual-phase (DP) and monophase (MP). Stone casts were produced through a conventional close tray impression technique using die stone. The casts were scanned with a laboratory scanner. DI was attained by scanning the implanted model with the IOS. The control sample was accomplished by scanning the implanted model directly with a laboratory scanner. Dimensional accuracy was calculated by measuring the distances between the reference points of four measuring parameters as follows; A-B, B-C, C-D, and A-D using CAD software.
RESULTS
The mean values and standard deviation between the four parameters of different impression techniques (CI and DI) and the control group showed convergent value. One-way ANOVA test showed all CI techniques, except IOS, showed a significant differences from the control group.
CONCLUSIONS
Compared with CI, the IOS was more accurate because no differences were observed between its measurements and those of the control model. CI is simple and reduces patient discomfort when used in fabricating multiple implants and allowing communication with dental technicians. Dimension accuracy, conventional impressions, digital impressions, multiple implants.
PubMed: 33981396
DOI: 10.4317/jced.57926 -
Journal of Indian Prosthodontic Society 2017A dental impression is a negative imprint of an oral structure that can be used to produce a positive cast of a patient's teeth as a permanent record. The accuracy of...
INTRODUCTION
A dental impression is a negative imprint of an oral structure that can be used to produce a positive cast of a patient's teeth as a permanent record. The accuracy of the impression affects the accuracy of the cast, and a precise impression is needed in order to create prosthesis with optimal fitting. Minimization of misfit is an important aim in prosthesis science and dental implants. The aim of this study was to evaluate the effects of the materials and techniques used to take an impression on the vertical misfit of implant-supported, screw-retained, three-unit bridges.
MATERIALS AND METHODS
The principal model used was an acrylic block with two ITI implants. A 1.5-mm abutment was attached to fixtures with torque of 25 N.cm. A base-metal framework was built on the abutment in the acrylic block. The abutments of the acrylic model were unscrewed and fixture-level impressions were made. The impression techniques included open/closed-tray techniques and the impression materials were polyether and polyvinyl siloxane. Forty acrylic custom trays were built for each impression. The marginal gap in the framework at three points (buccal, lingual, and distal) was measured using an optical microscope with ×250.
RESULTS
It is demonstrated that in all 360 evaluated samples, the mean vertical misfit in polyether samples of molar and premolar teeth was significantly lower than in polyvinyl siloxane ( < 0.001 and = 0.017, respectively) in all three locations of the molar and lingual premolar examined (buccal, lingual, and distal), the mean vertical misfit of the polyether samples was significantly lower than those of polyvinyl siloxane ( < 0.01). On the other hand, although the mean vertical misfit using the open-tray technique in the molar teeth was significantly lower than with the closed-tray method ( = 0.002), no statistical difference was seen between the open-tray and closed-tray technique in general ( = 0.87).
CONCLUSION
Within the limitations of this study, the following conclusions can be drawn: The impression method had no effect on marginal discrepancy of 3-unit screw retained fixed partial dentures. A higher marginal accuracy was obtained using polyether impression material compared to polyvinyl siloxane.
PubMed: 28216844
DOI: 10.4103/0972-4052.197937 -
Journal of Maxillofacial and Oral... Dec 2014Demonstrations and training on live-subjects are not always the optimal means of introducing the students to minor oral surgery. Hence, the use of teaching models permit...
INTRODUCTION
Demonstrations and training on live-subjects are not always the optimal means of introducing the students to minor oral surgery. Hence, the use of teaching models permit the students to handle the surgical instruments in a limited field under a semi-realistic circumstance and also helps in developing psychomotor skills in an non stressed situation. One among the competent exercise in oral surgery is suturing. Though there exist a variety of commercially available suturing training models, cost factor restrain their acquirement in few units.
METHODS & MATERIALS
This paper describes the construction of a simple and cost-effective suturing model for preclinical training. The construction of this model requires an orange peel, putty impression material and plaster of paris. This suturing model can be created in ten minutes.
CONCLUSION
This model can be constructed by the students with minimal effort and low cost in order to practice suturing.
PubMed: 26225037
DOI: 10.1007/s12663-013-0546-z -
Marine Drugs Jan 2022This study aimed to investigate the potential use of brown algae as irreversible hydrocolloid (alginate) impression material. Potassium alginate extracted from was...
This study aimed to investigate the potential use of brown algae as irreversible hydrocolloid (alginate) impression material. Potassium alginate extracted from was prepared in three different compositions (14%, 15%, and 16%) and mixed with other standard components to form an alginate impression material. Prior to that, the purity of potassium alginate was quantified with Fourier Transform Infrared Spectroscopy (FTIR) analysis. As a control material, the alginate impression material from a commercially available product was used. All alginate impression materials were then applied to a die stone model. Dimensional accuracy was measured by calculating the mesiodistal width of incisors in the generated dental cast using a digital caliper 0.01 accuracy (five replications). In addition, to evaluate the dimensional stability, the impression results were poured at four different periods (immediately, 5 min, 10 min, and 15 min). An independent -test was performed to compare the measurement results with < 0.05 considered significant. Analytical results confirm that the impression material containing 15% potassium alginate gives the best dimensional accuracy similar to control ( > 0.05). Meanwhile, the optimal dimensional stability was produced in the impression material containing 16% potassium alginate. Our study suggested that brown algae has a promising potential to be used as an alginate impression material in clinical application.
Topics: Animals; Aquatic Organisms; Colloids; Dental Impression Materials; Materials Testing; Sargassum
PubMed: 35049910
DOI: 10.3390/md20010055 -
Clinical Oral Investigations Feb 2022To compare the failure rates for three different adhesively retained core build-up composites up to the incorporation of a permanent fixed dental prosthesis (FDP), and... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
To compare the failure rates for three different adhesively retained core build-up composites up to the incorporation of a permanent fixed dental prosthesis (FDP), and to identify potential failure risk factors.
MATERIAL AND METHODS
A randomized controlled trial of 300 participants in need of a core build-up to restore a vital abutment tooth before prosthetic treatment was conducted. Participants were assigned by stratified block randomization to one of three study groups: Rebilda DC (RDC), Clearfil DC Core (CDC), or Multicore Flow (MF). Test teeth were prepared by use of the respective manufacturer's adhesive system. The total-etch technique was used for RDC and MF, and the self-etch technique for CDC. Participants were treated by dentists (n = 150) or dental students (n = 150). Failure rates of core build-ups before incorporation of FDPs were investigated using univariate and multiple logistic regression.
RESULTS
The overall failure rate was 8% (n = 23). Rate differences between the three investigated groups did not reach statistical significance (p > 0.05). The mean time between placement of core build-ups and placement of fixed dental prostheses was 12.2 (SD: 14.2) weeks. Conversely, larger cavities (> 3 surfaces) and treatment by dental students were independently associated with an increased failure risk (p < 0.05).
CONCLUSIONS
The main risk factors for early failure seem to be the size of the core build-up and clinical experience of the operator, whereas failure rates of core build-up materials combined with a self-etch approach seem to be similar to the rates of materials combined with the total-etch technique.
CLINICAL SIGNIFICANCE
This research article should give clinicians an impression of the short-term performance of different adhesively retained core build-ups using different adhesive techniques/materials. Moreover, predominant influencing factors for the success or failure should be pictured.
Topics: Dental Cements; Dental Restoration Failure; Humans; Post and Core Technique; Resin Cements
PubMed: 34491449
DOI: 10.1007/s00784-021-04170-6