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

2018 ◽  
Vol 1 (2) ◽  
pp. 67-74
Author(s):  
Anisha Pandey ◽  
S.R.B. Mathema ◽  
S.K. Maharjan
Keyword(s):  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Mean Value ◽  
Single Step ◽  
Vitro Study ◽  
Impression Technique ◽  
Group I ◽  
The Mean ◽  
Spacer Thickness

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. 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. 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. 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.

A Comparative Evaluation of Dimensional Accuracy and Surface Detail Reproduction for Polyvinyl Siloxane and Vinyl Siloxane Ether under Dry and Moist Conditions- An In-vitro Study

2021 ◽  
Author(s):  
Amit Baban Pokharkar ◽  
Umesh Gopal Palekar ◽  
Veena Saraf ◽  
Deepak Machindra Vikhe ◽  
Shefali Sevakram Bhiwapurkar ◽  
...  
Keyword(s):  
Statistical Difference ◽  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Dimensional Change ◽  
Vitro Study ◽  
Significant Difference ◽  
Moist Condition ◽  
The Mean ◽  
Surface Detail

Introduction: The conventional impression procedure plays a major role in prosthodontics inspite of advancement in intra- oral scanning devices and 3D imaging procedures. Dimensional accuracy and surface detail reproduction are important for recording an impression. Aim: The study evaluated and compared the dimensional accuracy and surface detail reproduction of Polyvinyl Siloxane (PVS) and vinyl siloxane ether impression materials when used under dry and moist conditions. Materials and Methods: An in-vitro study was conducted in the Department of Prosthodontics, Rural Dental College, Pravara Institute of Medical Sciences, Loni, Ahmednagar, Maharashtra, India, for a period of two years from October 2018 to September 2020. A total of 60 impressions were made with PVS (Group A) and vinyl siloxane ether (Group B) under dry (A1, B1) and moist (A2, B2) conditions of stainless steel dies which had lines engraved on superior surface of the die. Using a Harloc’s Tool maker’s microscope, dimensional accuracy was measured by comparing the width of line Y in each impression. Surface detail reproduction was evaluated by American Dental Association (ADA) specification no. 19 where it stated continuous replication of at least any two lines out of the three lines inscribed on the die. Data analysis processing was performed in the SYSTAT version 12 (made by Crane’s software, Bangalore). Student’s unpaired t-test and Chi-square test were performed to determine statistical difference between PVS and vinyl siloxane ether where the level of significance was set at 5% and 1%. Results: The mean dimensional change and SD values for PVS under dry condition ranged from 21.93±2.46 to 22.40±2.89 (in mm). The mean dimensional change and SD values for PVS under moist condition ranged from 22.87±3.20 to 23.33±3.42. The mean dimensional change and SD values for vinyl siloxane ether under dry condition ranged from 21.93±3.61 to 24.73±5.20. The mean dimensional change and SD values for vinyl siloxane ether under moist condition ranged from 21.93±4.48 to 22.87±4.15. No statistical difference was found under dry and moist conditions within 2 hours and after 24 hours for both the materials. Conclusion: The study revealed no significant difference between dimensional accuracy and surface detail reproduction for PVS and vinyl siloxane ether. Both the materials can reproduce the details under dry and moist conditions satisfactorily and remained dimensionally stable till 24 hours after impression making.

scholarly journals A comparative evaluation of three dimensional accuracy of different types of interocclusal recording materials - an in vitro study

2020 ◽  
Author(s):  
Aparna Dwivedi ◽  
Kavita Maru ◽  
Aakash Sharma
Keyword(s):  
Three Dimensional ◽  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Vitro Study ◽  
Time Intervals ◽  
Group I ◽  
Significant Difference ◽  
Different Types ◽  
Measuring Machine

Introduction. The interocclusal registration materials record the occlusal relationship between the natural and /or artificial teeth for planning an occlusal rehabilitation in removable and fixed partial dentures. Aim and objectives. The aim of this in vitro study was to evaluate and compare the accuracy and the three dimensional stability offered by three different types of interocclusal recording materials at storage time intervals of 1 hour and 24 hours. Methods. Three commercially available interocclusal recording materials were used - Group I - Polyether bite registration paste (Ramitec), Group II- Polyvinylsiloxane bite registration material (Imprint), Group III- Bite registration wax (Maarc).The test was carried out using an epoxy resin model. A total of 30 samples were made with each group consisting of ten samples. Three dimensional measurements were carried out by using 3D-Coordinate measuring machine (CMM) at time intervals of 0-1 hour and 0-24 hours in X, Y and Z- axis.   Results. Twelve readings were obtained for three axes (4 readings for each sample at 1 axis) and the averages of these four values were noted for a particular axis (X/Y/Z). Statistical analysis was performed using analysis of variance (ANOVA) for comparison among the groups and then Tukey’s honestly significant difference (HSD) tests was performed for comparison among groups at the 0.05 level of significance. Conclusion. Polyvinylsiloxane was dimensionally the most stable material followed by polyether and finally bite registration wax. Dimensional accuracy and stability is influenced by both “material” and “time” factors.

Chemomechanical Caries Removal in Primary Molars : Evaluation of Marginal Leakage and Shear Bond Strength in Bonded Restorations” - An in Vitro Study

2013 ◽  
Vol 37 (3) ◽  
pp. 269-274 ◽  
Author(s):  
PM Viral ◽  
C Nagarathna ◽  
B S Shakuntala
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
In Vitro Study ◽  
Vitro Study ◽  
Primary Molars ◽  
Strength Evaluation ◽  
Group I ◽  
Caries Removal ◽  
The Mean

Objectives : To evaluate and compare the efficiency, marginal leakage and shear bond strength of Carisolv and Papacarie in primary molars. Method: Freshly extracted 60 human carious primary molars were randomly divided into two experimental groups - Group I [ caries removal by Carisolv ] and Group II [ caries removal by Papacarie ]. The amount of time taken for complete caries removal was recorded using a stopwatch. After bonded restorations, both the experimental groups were further randomly subdivided into four experimental groups and subjected to marginal leakage and shear bond strength evaluation. Results : Papacarie [ 337.67 ± 18.13 ] was clinically more efficient than Carisolv [461.33 ± 27.76 ] in removing caries with respect to time in seconds. 66.7% of teeth treated with Carisolv did not show any marginal leakage as compared to 20% with Papacarie. The mean [ ± SD ] shear bond strength of Carisolv [ 9.67 ± 3.80 ] treated teeth was slightly more when compared to Papacarie [ 8.36 ± 4.51]. Conclusion :Papacarie was clinically more efficient in caries removal but showed significantly more marginal leakage than Carisolv.

scholarly journals Shear bond strength evaluation of bonded molar tubes on fluorotic molars

2012 ◽  
Vol 83 (1) ◽  
pp. 152-157 ◽  
Author(s):  
Erika L. Silva-Benítez ◽  
Veronica Zavala-Alonso ◽  
Gabriel A. Martinez-Castanon ◽  
Juan P. Loyola-Rodriguez ◽  
Nuria Patiño-Marin ◽  
...  
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Dental Fluorosis ◽  
In Vitro Study ◽  
Mean Value ◽  
Fixed Appliance ◽  
Adhesive Remnant Index ◽  
The Mean ◽  
Electronic Microscope

Abstract Objective: To study the shear bond strength (SBS), sites of failure, and micromorphology of bonded molar tubes used on teeth affected by dental fluorosis. Materials and Methods: This in vitro study included 140 first molars classified according to Dean's index for dental fluorosis. Samples were divided into seven groups: (1) healthy teeth etched for 15 seconds, (2) teeth with moderate fluorosis (MOF) etched for 15 seconds, (3) teeth with MOF etched for 150 seconds, (4) teeth with MOF microabrasion etched for 15 seconds, (5) teeth with severe fluorosis (SEF) etched for 15 seconds, (6) teeth with SEF etched for 150 seconds, and (7) teeth with SEF microabrasion etched for 15 seconds. All samples were incubated and were then submitted to the SBS test and evaluated with the modified adhesive remnant index (ARI) and analyzed by using a scanning electronic microscope. Results: The SBS mean value for healthy enamel was 20 ± 10.2 MPa. For the group with MOF, the etched 150-second mean value was the highest (19 ± 7.6 MPa); for the group with SEF treated with microabrasion and etched for 15 seconds, the mean value was (13 ± 4.1 MPa). Significant differences (P ≤ .05) were found in the ARI between healthy and fluorosed groups. Conclusions: Fluorotic enamel affects the adhesion of bonded molar tubes. The use of overetching in cases of MOF and the combination of microabrasion and etching in SEF provides a suitable adhesion for fixed appliance therapy.

scholarly journals Assessment of shear bond strength of brackets bonded by direct and indirect techniques: an in vitro study

2012 ◽  
Vol 17 (4) ◽  
pp. 1-7 ◽  
Author(s):  
Roberto Hideo Shimizu ◽  
Karlos Giovani Grando ◽  
Isabela Almeida Shimizu ◽  
Augusto Ricardo Andriguetto ◽  
Ana Cláudia Moreira Melo ◽  
...  
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
In Vitro Study ◽  
Adhesive System ◽  
Vitro Study ◽  
Group Iii ◽  
Indirect Bonding ◽  
Group I ◽  
Group Ii

OBJECTIVE: This in vitro study was designed to evaluate the shear bond strength (SBS) of orthodontic metal brackets bonded by direct and indirect techniques. METHODS: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with SondhiTM Rapid-Set system (3M/Unitek), Group II - indirect bonding with TransbondTM XT adhesive system (3M/Unitek) and Group III - direct bonding with TransbondTM XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukey's test for paired means. A 5% significance level was adopted. RESULTS: The results of Group I were 67.6 (N) and 5.9 (MPa); Group II, 68.9 (N) and 6.1 (MPa) and Group III (control), 92.5 (N) and 8.1 (MPa). CONCLUSION: It can therefore be concluded that the means for Group III were significantly higher compared with Groups I and II in both Newton (N) and Megapascal (MPa) values. The means attained by the indirect bonding technique used in Groups I and II, however, exhibited no statistically significant differences.

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