Putty-wash Technique Research Articles

Clinical evaluation of marginal fit of uncemented CAD-CAM monolithic zirconia three-unit restorations in anterior areas, using scannable and conventional polyvinyl siloxane impression materials

BackgroundThe accuracy of impression techniques determines the marginal fit of fixed prostheses. Marginal accuracy plays a main role in the success and failure of treatments. This in-vivo study evaluated the marginal fit of anterior three-unit monolithic zirconia fixed partial dentures (FPDs) using conventional and scannable polyvinyl siloxane impression materials.MethodsTen patients were selected to replace the lateral teeth with a three-unit monolithic zirconia bridge. For each patient, in the first group, an impression was made with a two-step putty-wash technique using scannable polyvinyl siloxane material (BONASCAN; DMP, Greece). In the identical session, as the second group, an impression of conventional putty-wash polyvinyl siloxane was taken (BONASIL A+ Putty; DMP, Greece). The marginal discrepancy was measured through the replicas, which were cut perpendicularly within the buccolingual and mesiodistal directions. An Independent t-test was employed for data analyses (P < 0.05).ResultsThe marginal discrepancy in a conventional method for central abutment in mid-buccal, mid-lingual, mid-mesial, and mid-distal was higher than in the scannable method but it was not significant (P > 0.05). Also, the marginal discrepancy for canine abutment in the conventional method was higher than in the scannable method, but it was not significant, either (P > 0.05).ConclusionsFPDs fabricated from both scannable and conventional impression materials were not superior to each other in marginal fit for both central and canine abutments by evaluation using the replica technique.

Comparative Evaluation of the Dimensional Accuracy of Different Putty-Wash Techniques Using Additional Silicon Impression Material In Vitro Study

Purpose: The aim of the present study was to evaluate and compare the dimensional accuracy of stone models made by addition silicone impression material using three putty- wash impression techniques: one step putty wash (dual viscosity), two step and modified two step putty wash technique. Material and Methods: A stainless steel master model was constructed simulating a three-unit fixed prosthesis. Fifteen impressions were make of this master model with each impression technique. The first technique, one step dual viscosity was made with putty in the tray and light body on brass dies and impression was make. The second technique, two step putty/wash, the first step using putty on the tray with acrylic spacer on the dies and impression was make then followed by loading wash material on the dies and reseating the first impression in the second step. The third technique, modified two step made using putty/light body as in the first technique then a hole was made at the edge of two abutments in the polymerized impression, then light body was loaded into the tray and over the model and the tray is reseated. Total of forty five impressions were obtained and casts poured using type IV stone. The accuracy of these casts measured using a travelling microscope. Three dimensions diameter, height, and interabutment distances measurements were obtained and statistical analysis was done using paired T-test, One way ANOVA, and Least Significant Difference (LSD) tests. Result: Showed that a significantly larger dimensions of the resultant stone casts of all techniques in comparison to the master model (P

Dimensional accuracy and surface detail reproduction of hydrophilic polyvinylsiloxane impression material tested under dry and moist salivary conditions: An In vitro study

Background: The dimensional accuracy and surface detail reproduction of impression materials play a major role in determining the extent to which indirectly produced prostheses and restorations have an acceptable fit. The purpose of the present study was to compare the dimensional accuracy and surface detail reproduction of hydrophilic polyvinylsiloxane (PVS) impression material tested under dry and moist salivary conditions. Methods: The study samples were assigned two groups based on the condition in which they were made. One group consisted of casts obtained from impressions made in dry condition (n = 12), while the other group consisted of casts obtained from impressions made in moist salivary conditions (n = 12). Impressions of the master model were made using hydrophilic PVS impression material by two-step putty-wash technique and working casts were obtained. Dimensional accuracy was measured by comparing the inter-abutment distance in each cast to the master model using a profile projector with an accuracy of 0.001 mm, while surface detail reproduction was evaluated using the American Dental Association specification No. 19 criteria of continuous replication of at least two of the three horizontal lines. Descriptive statistics such as mean and standard deviation were calculated for both the groups. Differences from the master model were analyzed by paired t–test, while one-way analysis of variance (ANOVA) was used for intergroup comparisons. P ≤ 0.05 was considered statistically significant. Results: One-way ANOVA revealed a highly significant difference in the dimensional accuracy of impressions made under moist conditions as against those which were made under dry condition (P

Impression material accuracy for palatal orthodontic miniscrews.

PurposeThis 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.MethodsIn 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).ResultsOptimal 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.ConclusionsWithin 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.

Effect of heat sterilization and chemical method of sterilization on the polyvinyl siloxane impression material. A comparative study

Background:Dental impression is a crucial part of the process of constructing a well-fitting prosthesis. In the clinical scenario, impressions can act as a vehicle for the transfer of bacteria and fungi. Therefore, an attempt was made to evaluate the dimensional accuracy of the newly introduced polyvinyl siloxane (PVS) impression material upon autoclaving and comparing it to the traditional means of chemical disinfection.Materials and Methods:A cross-sectional comparative in vitro study was conducted. Three groups were made for testing different sterilization methods. The sample size for the study was kept as 30 observations in each of the three groups. Test samples were prepared by making an impression of the die using the putty-wash technique. Statistical analysis was done by applying unpaired t-test, paired t-test, one-way analysis of variance (ANOVA) and post hoc Tukey's honestly significant difference (HSD).Results:Initial mean of samples of group I were compared to A (actual measurement of metal ruled block = 24.960), a dimensional change of 1.6% was found. Similarly, in group II, a change of 1.59% was found and in group III the change was 1.7%. There was mean shrinkage of 24.557 mm in group I, 24.586 mm in group II, and 24.535 mm in group III and these changes were found statistically significant.Conclusion:Dimensional changes in the impression material after disinfection with 2% glutaraldehyde were considered high compared to autoclaving and, hence, it may not be advisable to disinfect this material with 2% glutaraldehyde.

A Comparative Study to Evaluate the Accuracy of Various Spacer Thickness for Polyvinyl Siloxane Putty-wash Impression Techniques: An In Vitro Study.

IntroductionAn accurate impression is one of the prime factors for success of any restoration, more so in field of fixed prosthodontics. The critical aspect is to reproduce fine surface details along with ease of use. Knowledge of impression materials and the techniques to which each is best suited is essential in achieving consistent results.Objective of the studyThe purpose of this study is to evaluate the accuracy of various putty-wash techniques in a laboratory model that simulated the clinical practice.Materials and methodsA metal master model, containing three full crowns fixed partial denture (FPD) abutment preparations, was fabricated. A perforated custom tray was fabricated that can be placed in the same position on the master model for each impression. For each technique, 10 impressions of the master model were made and poured using a die stone. The measurements were made of the models using a measuroscope and the accuracy of the impressions was recorded.ResultsThe statistical comparison between groups I, II, III, and IV casts measurements by using the Mann–Whitney test showed highly significant statistical difference between the various groups from each other (p < 0.001)ConclusionThe accuracy of the working casts obtained from group III impression (two-step using 1 mm coping) was the best, whereas it was least with group II impression (two-step using polyethylene spacer).How to cite this articleGautam N, Ahmed R, Sharma S, et al. A Comparative Study to Evaluate the Accuracy of Various Spacer Thickness for Polyvinyl Siloxane Putty-wash Impression Techniques: An In Vitro Study. Int J Clin Pediatr Dent 2020;13(5):536–542.

Comparison of Dimensional Accuracy of Cast Obtained from Polyvinyl Siloxane Impression with Different Putty-Wash Techniques and Spacer Thickness - In Vitro Study

Introduction: Dimensional accuracy of cast obtained after making impressions is crucial factor for the quality of fixed prosthodontic treatment. The impression technique with different thickness of putty wash material is critical factor affecting this accuracy. There is much discussion in the dental literature concerning the effect of this impression technique on the accuracy of cast restorations.&#x0D; Materials and methods: This in-vitro study was carried out in 60 impression made from master model with Polyvinyl siloxane impressions material using single step putty- wash technique and two step putty-wash technique with varying spacer thickness (0.5mm, 1mm, 1.5 mm). It was further divided into four groups. Group I: Single step putty-wash impression technique, Group II: Two step putty-wash impression technique with 0.5mm spacer, Group III: Two step putty-wash impression technique with 1mm spacer, Group IV: Two step putty-wash impression technique with 1.5mm spacer. Each group consists of 15 impressions. Casts were poured using type IV dental stone after 1 hour. After 24 hour the die of each cast was scanned using CAD/CAM digital scanner and measured mesiodistally, facio-lingually, height (cervico-occlusally), interabutment or interdie distances. The data were recorded and statically analyzed.&#x0D; Results: The highest mean values of mesio-distal, bucco-lingual, cervico-occlusal distances were shown by Group I, whereas the inter-die distance showed equal mean value in Group I, II and III. With the increase in the spacer thickness, the mean value also increases in mesio-distal distance. The mean measurement of bucco-lingual dimension was highest when spacer thickness was 0.5mm and it declined with the increase in spacer thickness. The spacer thickness had no effect on cervico-occlusal and inter-die dimensions.&#x0D; Conclusions: Within the limitations of the study, accuracy of cast obtained from single step putty-wash technique was more accurate than two step putty-wash technique. In two step putty-wash technique, 1.5 mm thickness of spacer showed more accurate cast in comparison to 0.5mm and 1mm.

Comparative Analysis of Dimensional Accuracy of Two Types of Silicone Impression Materials: Optosil and Elite-HD

Statement of the Problem: Understanding about impression materials, their properties, uses and manipulation can guide operators towards having more successful restorations. Purpose: The aim of this in vitro study was to compare the accuracy of a condensation silicone impression material, Optosil, and an addition poly siloxane impression material, Elite-HD. Materials and Method: A laboratory model with two metallic dies was used to make impression. A horizontal notch on one of the two dies simulated an undercut. Ten impressions were made by each impression material by the putty-wash technique. After pouring impressions with velmix die stone, a total of 20 stone casts were made from both materials. Measurements of casts were compared with the master model. Statistical analyses were performed using t-test. Result: This results of this study showed that the height of die without undercut decreased in both groups. Also the height above the undercut decreased in both groups, which was more obvious in Elite-HD group than Optosil group. The distance between dies increased in both groups, with higher figures for Elite-HD. So, Optosil is a more accurate material for registering inter-abutment distance than Elite-HD. The diameter of die under the undercut decreased in Optosil group and was similar to the master model in Elite-HD. Statistical analysis showed significant differences between these two groups in the distance between abutments (p=0.001), the diameter of die under the undercut (p=0.014) and the height of die above undercut(p=0.057). Conclusion: Optosil is more accurate in registering inter-abutment distance than Elite-HD, so Optosil is preferred for fixed partial denture impressions. Since Elite-HD showed more accuracy in C measurements than Optosil, it is preferred for single crown impressions.

Accuracy of a separating foil impression using a novel polyolefin foil compared to a custom tray and a stock tray technique.

PURPOSETo compare the dimensional accuracy of three impression techniques- a separating foil impression, a custom tray impression, and a stock tray impression.MATERIALS AND METHODSA machined mandibular complete-arch metal model with special modifications served as a master cast. Three different impression techniques (n = 6 in each group) were performed with addition-cured silicon materials: i) putty-wash technique with a prefabricated metal tray (MET) using putty and regular body, ii) single-phase impression with custom tray (CUS) using regular body material, and iii) two-stage technique with stock metal tray (SEP) using putty with a separating foil and regular body material. All impressions were poured with epoxy resin. Six different distances (four intra-abutment and two inter-abutment distances) were gauged on the metal master model and on the casts with a microscope in combination with calibrated measuring software. The differences of the evaluated distances between the reference and the three test groups were calculated and expressed as mean (± SD). Additionally, the 95% confidence intervals were calculated and significant differences between the experimental groups were assumed when confidence intervals did not overlap.RESULTSDimensional changes compared to reference values varied between -74.01 and 32.57 µm (MET), -78.86 and 30.84 (CUS), and between -92.20 and 30.98 (SEP). For the intra-abutment distances, no significant differences among the experimental groups were detected. CUS showed a significantly higher dimensional accuracy for the inter-abutment distances with -0.02 and -0.08 percentage deviation compared to MET and SEP.CONCLUSIONThe separation foil technique is a simple alternative to the custom tray technique for single tooth restorations, while limitations may exist for extended restorations with multiple abutment teeth.

A modified technique for making putty-wash two-step impression

Background: If the impression thickness is uniform, stock trays can also give a better result when compared to custom trays. Purpose: This study aimed to obtain a uniform thickness impression with a modified putty-wash two-step technique. Materials and Methods: A chairside method of putty-wash two-step impression in a stock tray was made utilizing a wax spacer. Results: A uniform thickness impression was obtained in stock tray in quick time. Conclusion: The current article has given the options of using wax as spacer for making putty wash two step impressions for the fabrication of tooth-supported fixed restorations. Further research is required to find whether there is any dimensional inaccuracy caused in restorations due to usage of wax as a spacer.

Effect of Intermixing Brands on the Dimensional Accuracy of Master Cast using Putty-wash Impression Technique.

The aim of this study was to evaluate the effect of intermixing brands of addition silicone impression materials on the dimensional accuracy of stone models using two-step putty-wash technique. Two common brands of addition silicone impression material (Express and Aquasil) were used in this study. A total of 40 impressions of a stainless steel model simulating a three-unit bridge were made, 10 impressions for each group. Accuracy was assessed by measuring two dimensions (inter-abutment and intra-abutment) on stone models obtained from impressions of the stainless steel model. Each sample was measured thrice and the mean value was calculated. The data were analyzed using analysis of variance (ANOVA) and Scheffe's post hoc test. The results indicated that each of the inter-abutment and intra-abutment dimensions of the stone models was significantly higher than those for the stainless steel model (p < 0.001). However, there was no statistically significant difference in each of the inter-abutment and intra-abutment dimensions of the stone models among the four tested groups (p < 0.05). The results obtained were statistically analyzed and the values of the inter-abutment and intra-abutment dimensions were all within the clinically acceptable range. Intermixing brands of additional silicone impression materials evaluated in this study did not affect the dimensional accuracy of obtained stone casts. This will help to minimize the wastage of materials due to lack of either light or putty consistency of the same brand of additional silicone impression material.

Effects of the space for wash materials on sulcus depth reproduction with addition-curing silicone using two-step putty-wash technique

Aim of this study was to investigate effects of space thickness and consistency of wash materials on sulcus depth reproduction with silicone impressions, low (L), medium (M), and very high consistency (VH), using two-step putty-wash technique. Impressions were taken from truncated cones with 50-, 100-, or 200-μm-wide sulci, using the combinations L+VH or M+VH and different space thickness for wash materials: 2 mm (ST2), 1 mm (ST1), and approximately 25 μm (ST0.025). Sulcus depth reproduction tended to increase with increasing sulcus width. Sulcus reproduction of ST0.025 was deeper than those of the other groups. At 100- and 200-μm sulcus widths, sulcus reproductions of ST1 and ST2 with L+HV were deeper than with M+HV. Regardless of consistency, the thin spacer produced deep reproduction. Adequate 0.5 mm sulcus reproductions were obtained with 100 and 200 μm wide sulci and 1- and 2-mm spacer widths, combined with low consistency impression material.

Accuracy of different putty-wash impression techniques with various spacer thickness.

ABSTRACTOne of the most important steps is accurate impression making for fabrication of fixed partial denture.The two different putty-wash techniques that are commonly used are: (1) Putty-wash one-step technique, (2) putty-wash two-step technique.A uniform wash space is needed for an accurate impression. Nissan et al recommended the use of two-step technique for accurate impression making as there is uniform wash space for the light body material to polymerize.The aim of the present study was to compare the accuracy of stone casts obtained from different putty-wash impression techniques using various spacer thickness.The critical factor that influences the accuracy of putty-wash impression techniques is the controlled wash bulk which is absent in one-step putty-wash impression technique and with polyethylene spacer was used.How to cite this article: Chugh A, Arora A, Singh VP. Accuracy of Different Putty-Wash Impression Techniques with Various Spacer Thickness. Int J Clin Pediatr Dent 2012;5(1):33-38.

Effect of different retraction and impression techniques on the marginal fit of crowns

Objectives Periodontal conditions in restored teeth are strongly influenced by the marginal fit of the restoration which is closely related to the quality of the impression. However, the influence of the retraction and impression technique on the outcome of the impression has only sparsely been investigated. Thus, it was the objective of this study to compare the marginal fit in fixed restorations using two modes of gingival retraction and two different impression techniques in an animal model. Methods To simulate clinical conditions, 6 teeth in each of 10 lower jaws of freshly slaughtered cows were prepared with subgingival finish lines. Two different retraction techniques were used to expose the finish line: retraction cords containing epinephrine ( Surgident) and electro-surgery were applied contra-laterally at 3 teeth per quadrant. Two impressions per jaw were taken in a two-step putty-wash technique (TPW) and a one-step putty-wash technique (OPW), respectively. On the casts, measurement copings were fabricated and seated on the extracted original tooth. In each coping the marginal discrepancy was assessed at 8 reference marks. Since the data was normally distributed, results were subjected to parametric statistics ( T-test; p = 0.05). Results Overall marginal discrepancies ranged between 0 and 200 μm. There was a small but not significant difference between electro-surgery and the retraction cords whereas TPW produced significantly better results than OPW ( p < 0.05). Conclusions Within the limits of the study it can be concluded that the use of gingival retraction cords as well as electro-surgery lead to acceptable results. The difference between TPW and OPW concerning the marginal discrepancies can be regarded as clinically insignificant.

A modified one-step putty-wash impression technique

aClinical Instructor, Chang Gung Memorial Hospital, Chang Gung University College of Medicine. bProfessor, School of Dentistry, University of North Carolina. (J Prosthet Dent 2007;98:245-246) Although the literature demonstrates that optimum accuracy can be achieved with custom trays and stock trays,1-4 the putty-wash impression technique using an elastomeric impression material is a popular method. Two variations of the putty-wash impression technique are commonly used, the 2-step and 1-step.5 With the 2-step technique, a preliminary preoperative putty impression is made and, subsequently, “washed” with low viscosity material after tooth preparation. In terms of the 2-step puttywash impression technique, several methods are described for control of the bulk of the wash material,6-8 which is essential for fabricating accurate stone dies. With the 1-step procedure, low viscosity impression material is injected around the prepared tooth or teeth, and then the putty impression material is immediately placed intraorally and the materials polymerize simultaneously. Accuracy of impressions resulting from the 1-step putty-wash technique is controversial. Some authors found that there was no difference in accuracy between techniques,5,9-11 while others criticized several potential disadvantages with this approach. These disadvantages include lack of control of the bulk of wash material and the high risk of capturing portions of the prepared margin in putty material rather than lower viscosity material.12 Most putty viscosity materials have inadequate fine detail reproduction for this purpose. This article describes a modified 1-step putty-wash technique using vacuum-formed resin sheets as spacers to control the wash bulk and minimize the chance of unfavorable impression results. Using this technique, the limitations of using 1-step putty-wash impression can be eliminated.

Influence of margin design on the fit of high-precious alloy restorations in patients

It was the objective of this study, to analyze the influence of the marginal design on the marginal accuracy of a casting in a clinical setup in patients. Ninety volunteer patients' teeth-which were intended for extraction due to medical reasons-were prepared prior to extraction. Three different types of finishing line-chamfer, 135 degrees shoulder and 90 degrees shoulder-were employed. Two each c-silicone and pvs impressions were taken of each tooth using either a two-stage or a one-stage putty-wash technique. After preparation and impression taking the teeth were extracted. Gypsum casts were poured from the impressions and high precious alloy castings fabricated on the dies and marginal discrepancies were determined on the extracted teeth. The median value of marginal discrepancies was lower than 150 microm for all groups. The difference between the three different preparation types was significant (H-test, p<0.05). The lowest median values were obtained for the chamfer preparations, while the 90 degrees shoulders always produced the highest median values. Preparations at gingva level exhibited more accurate marginal fit than subgingival preparations. No significant differences could be observed between the pvs and c-silicone materials or the one-step and two-step putty-wash techniques. The marginal designs of the preparations had much less influence on the marginal fit of high precious alloy castings than expected. There is considerable reason to assume that technical but clinical parameters influence the quality of fixed prosthodontics much more than has been believed in the past.

A controlled putty-wash impression technique

A precise impression is imperative for the construction of an accurately fitting indirect cast restoration. The putty-wash technique is commonly used in making impressions with silicone elastomers. Errors in manipulation may lead to inaccurate impressions. A technique is presented ensuring exact reseating of the putty impression tray and creation of a uniform wash space, which are essential for accurate results.