scholarly journals Comparison of Accuracy of Direct Implant Impression Technique using Different Splinting Materials

2014 ◽  
Vol 4 (3) ◽  
pp. 82-89
Author(s):  
Sunantha Selvaraj ◽  
Jayashree Mohan ◽  
Paul Simon ◽  
Jayachandran Dorairaj
Keyword(s):  
Reference Model ◽  
Coordinate Measuring Machine ◽  
Critical Factor ◽  
Acrylic Resin ◽  
Impression Material ◽  
Impression Technique ◽  
Direct Technique ◽  
Measuring Machine ◽  
Group B ◽  
Similar Accuracy

ABSTRACT Introduction The accuracy of an impression remains critical factor in achieving passive fit of an implant framework. The accuracy of the master cast would depend on the type of impression material, the implant impression technique and accuracy of die material. The different impression techniques advocated in the literature for implant impressions include direct (open tray) and indirect (closed tray) techniques. Direct technique use square impression copings that are picked up in the impressions which were used in this study. Objective To evaluate the accuracy of direct impression made with resin splinted and bis-GMA splinted open-tray impression coping. Thus to compare the accuracy of impressions obtained using different splinting materials. Materials and Methods A wax mandibular reference model was fabricated and four implants were placed in the mandibular anterior region using surveyor and acrylized with clear heat cure acrylic resin using injection molding technique. Spaced primary cast was fabricated with a uniform thickness of space about 2 mm. Ten custom trays were fabricated using the light curable resin sheets. Medium body polyether impression material was used. Pentamix was used to get a uniform mix. These trays were randomly divided among the two groups, with five trays in each group. Impression techniques were divided into two groups namely:   Group A - direct impression technique with open tray impression copings splinted with autopolymerizing acrylic resin (GC pattern resin), group B - direct impression technique with open tray impression copings splinted with Protemp TM4 (bis- GMA) syringable temporisation material. Thus, final impressions were made. Total of 10 master casts were fabricated. Evaluation of casts using Dynascope-Vision engineering, Tesa Microhite 2D and coordinate measuring machine were used. Results Statistical comparisons were made using ANOVA test and post-hoc test. Same amount of deviation values obtained with resin splinted and bis-GMA splinted impression copings. The difference in the values might be because of the variation in the rigidity of the materials used. Conclusion Both the splinting material exhibit similar accuracy in impression, so bis-GMA can be used, which is easy to handle, less time consuming, less technique sensitive, rigid and readily available material in clinics, instead of resin splinted material which is technique sensitive, more time consuming and cumbersome. How to cite this article Selvaraj S, Mohan J, Simon P, Dorairaj J. Comparison of Accuracy of Direct Implant Impression Technique using Different Splinting Materials. Int J Prosthodont Restor Dent 2014;4(3):82-89.

scholarly journals In Vitro Comparative Evaluation of Different Types of Impression Trays and Impression Materials on the Accuracy of Open Tray Implant Impressions: A Pilot Study

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Sonam Gupta ◽  
Aparna Ichalangod Narayan ◽  
Dhanasekar Balakrishnan
Keyword(s):  
Reference Model ◽  
Coordinate Measuring Machine ◽  
Dimensional Accuracy ◽  
Impression Material ◽  
Impression Materials ◽  
Significant Difference ◽  
Different Types ◽  
Measuring Machine ◽  
The Difference

Purpose. For a precise fit of multiple implant framework, having an accurate definitive cast is imperative. The present study evaluated dimensional accuracy of master casts obtained using different impression trays and materials with open tray impression technique.Materials and Methods. A machined aluminum reference model with four parallel implant analogues was fabricated. Forty implant level impressions were made. Eight groups (n=5) were tested using impression materials (polyether and vinylsiloxanether) and four types of impression trays, two being custom (self-cure acrylic and light cure acrylic) and two being stock (plastic and metal). The interimplant distances were measured on master casts using a coordinate measuring machine. The collected data was compared with a standard reference model and was statistically analyzed using two-way ANOVA.Results. Statistically significant difference (p<0.05) was found between the two impression materials. However, the difference seen was small (36 μm) irrespective of the tray type used. No significant difference (p>0.05) was observed between varied stock and custom trays.Conclusions. The polyether impression material proved to be more accurate than vinylsiloxanether impression material. The rigid nonperforated stock trays, both plastic and metal, could be an alternative for custom trays for multi-implant impressions when used with medium viscosity impression materials.

scholarly journals Evaluation of dimensional accuracy of dental bridges manufactured with conventional casting technique and CAD/CAM system with Ceramill Sintron blocks using CMM

2018 ◽  
Vol 12 (4) ◽  
pp. 264-271 ◽  
Author(s):  
Alireza Izadi ◽  
Fariborz Vafaee ◽  
Arash Shishehian ◽  
Ghodratollah Roshanaei ◽  
Behzad Fathi Afkari
Keyword(s):  
Reference Model ◽  
Coordinate Measuring Machine ◽  
Dimensional Accuracy ◽  
Three Dimensions ◽  
Casting Technique ◽  
Dimensional Changes ◽  
Conventional Casting ◽  
Cad Cam ◽  
Milling Method ◽  
Measuring Machine

Background. Recently, non-presintered chromium-cobalt (Cr-Co) blocks with the commercial name of Ceramill Sintron were introduced to the market. However, comprehensive studies on the dimensional accuracy and fit of multi-unit frameworks made of these blocks using the coordinate measuring machine (CMM) are lacking. This study aimed to assess and compare the dimensional changes and fit of conventional casting and milled frameworks using Ceramill Sintron. Methods. A metal model was designed and scanned and 5-unit frameworks were fabricated using two techniques: (I) the conventional casting method (n=20): the wax model was designed, milled in the CAD/CAM machine, flasked and invested; (II) the milling method using Ceramill Sintron blocks (n=20): the wax patterns of group 1 were used; Ceramill Sintron blocks were milled and sintered. Measurements were made on the original reference model and the fabricated frameworks using the CMM in all the three spatial dimensions, and dimensional changes were recorded in a checklist. Data were analyzed with descriptive statistics, and the two groups were compared using one-way ANOVA and Tukey test (α=0.05). Results. The fabricated frameworks in both groups showed significant dimensional changes in all the three dimensions. Comparison of dimensional changes between the two groups revealed no significant differences (P>0.05) except for transverse changes (arch) that were significantly greater in Ceramill Sintron frameworks (P<0.05). Conclusion. The two manufacturing processes were the same regarding dimensional changes and the magnitude of marginal gaps and both processes resulted in significant dimensional changes in frameworks. Ceramill Sintron frameworks showed significantly greater transverse changes than the conventional frameworks.

Evaluation of Accuracy of Casts of Multiple Internal Connection Implant Prosthesis Obtained From Different Impression Materials and Techniques: An In Vitro Study

2014 ◽  
Vol 40 (2) ◽  
pp. 137-145 ◽  
Author(s):  
Malesh Pujari ◽  
Pooja Garg ◽  
D. R. Prithviraj
Keyword(s):  
Reference Model ◽  
In Vitro Study ◽  
Acrylic Resin ◽  
Vitro Study ◽  
Impression Material ◽  
Internal Connection ◽  
Impression Materials ◽  
Significant Difference ◽  
Multiple Comparison Procedures

Movement of impression copings inside the impression material using a direct (open tray) impression technique during clinical and laboratory phases may cause inaccuracy in transferring the 3-dimensional spatial orientation of implants intraorally to the cast. Consequently, the prosthesis may require corrective procedures. This in vitro study evaluated the accuracy of 3 different impression techniques using polyether and vinyl polysiloxane (VPS) impression material to obtain a precise cast for multiple internal connection implants. A reference acrylic resin model with 4 internal connection implants was fabricated. Impressions of the reference model were made using 3 different techniques and 2 different impression materials. The study consisted of 24 specimens divided into 6 groups of 4 each. Impressions were poured with ADA type IV stone (Kalrock, Kalabhai Karson Pvt Ltd, Mumbai, India). All casts were evaluated for the positional accuracy (mm) of the implant replica heads using a profile projector. These measurements were compared to the measurements calculated on the reference resin model, which served as a control. Data were analyzed with 2-way analysis of variance (ANOVA) followed by Bonferroni multiple comparison procedures to evaluate group means. The results revealed significant difference for anterior implant distance between the 2 impression materials (P &lt; .01) and also among the 3 different techniques (P &lt; .05). The lowest mean variation was found with the polyether impression material and the splinted technique. For posterior implants, the results suggested no significant difference between the 2 impression materials (P ≥ .05). Although results were not statistically significant, the polyether impression material showed the lowest mean variation as compared to the VPS impression material. However, there was a significant difference among the 3 different techniques (P &lt; .05). Among the 3 different techniques, the lowest mean variation between 2 posterior implants was found in the splinted technique. Casts obtained from impression techniques using square impression copings splinted together with autopolymerizing acrylic resin prior to the impression procedure were more accurate than casts obtained from impressions with nonmodified implant impression copings and with airborne particle–abraded, adhesive-coated copings. Casts obtained from polyether impression material were more accurate than casts obtained from vinyl polysiloxane impression material.

scholarly journals Dimensional Accuracy of Stone Casts Obtained with Multiple Pours into the Same Mold

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Valdimar da Silva Valente ◽  
Artêmio Luiz Zanetti ◽  
Pedro Paulo Feltrin ◽  
Ricardo Tatsuo Inoue ◽  
Carmem Dolores Vilarinho Soares de Moura ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Coordinate Measuring Machine ◽  
Dimensional Accuracy ◽  
Wait Time ◽  
Type Iv ◽  
Impression Technique ◽  
Fixed Prosthesis ◽  
Measuring Machine ◽  
Master Model ◽  
Made In

Aim. The aim of the present study was to compare the dimensional accuracy of stone casts obtained with vinyl polysiloxane molds through the double-impression technique with three pours into the same mold. Methods. A stainless steel master model was constructed simulating a three-unit fixed prosthesis. Twelve impressions were taken of this master model with addition silicone, using the double-impression technique. Three pours of type IV gypsum were then made into each mold, thus producing 36 casts. The pours were made 1 hour, 6 hours and 24 hours after the impression procedure. Next, intra- and interabutment measurements were made in a coordinate measuring machine. Results. Comparative analysis of the dimensional accuracy of stone casts resulting from multiple pours was not statistically significant in pours first and second (P>0.05). These values, however, were statistically significant at third pour in the height in abutment 1 and upper distance interabutment. Conclusion. The wait time (1 hour, and 6 hours) observed before pouring the stone into the same molds did not cause significant dimensional accuracy of the casts.

scholarly journals Measurement of the accuracy of dental working casts using a coordinate measuring machine

2016 ◽  
Vol 73 (10) ◽  
pp. 895-903 ◽  
Author(s):  
Michal Potran ◽  
Branko Strbac ◽  
Tatjana Puskar ◽  
Miodrag Hadzistevic ◽  
Janko Hodolic ◽  
...  
Keyword(s):  
Coordinate Measuring Machine ◽  
Impression Material ◽  
Type Iv ◽  
Impression Accuracy ◽  
Dental Impression ◽  
Abutment Teeth ◽  
Measuring Machine ◽  
Master Model ◽  
Degree Of Convergence

Background/Aim: Dental impressions present a negative imprint of intraoral tissues of a patient which is, by pouring in gypsum, transferred extraorally on the working cast. Casting an accurate and precise working cast presents the first and very important step, since each of the following stages contributes to the overall error of the production process, which can lead to inadequately fitting dental restorations. The aim of this study was to promote and test a new model and technique for in vitro evaluation of the dental impression accuracy, as well as to asses the dimensional stability of impression material depending on the material bulk, and its effect on the accuracy of working casts. Methods. Impressions were made by the monophasic technique using the experimental master model. Custom trays with spacing of 1, 2 and 3 mm were constructed by rapid prototyping. The overall of 10 impressions were made with each custom tray. Working casts were made with gypsum type IV. Measurement of working casts was done 24 h later using a co-ordinate measuring machine. Results. The obtained results show that the working casts of all the three custom trays were in most cases significantly different in the transversal and sagittal planes in relation to the master model. The height of abutments was mainly unaffected. The degree of convergence showed certain significance in all the three custom trays, most pronounced in the tray with 3 mm spacing. Conclusion. The impression material bulk of 1?3 mm could provide accurate working casts when using the monophasic impression technique. The increase of the distance between abutment teeth influences the accuracy of working casts depending on the material bulk.

Routine Monitoring DCC CMM using Laser Interferometer

2019 ◽  
Vol 5 (1) ◽  
pp. 7-14
Author(s):  
Paulus Agung Krismantara
Keyword(s):  
Laser Interferometer ◽  
Computer Control ◽  
Coordinate Measuring Machine ◽  
Critical Factor ◽  
Machine Error ◽  
Machine Age ◽  
Machine Errors ◽  
Routine Monitoring ◽  
Measuring Machine ◽  
Consistent Performance

Manufacturing deals with the high quality product due to the accuracy which produced by measuring machines. In other case, the performance of regular diagnostic of measuring machine should be maintained to aim confidence and reliability in the measurements result. One of the equipment that can reach high accuracy is Direct Computer Control Coordinate Measuring Machine (DCC CMM). The accuracy of DCC CMM is a critical factor that affects result of product measuring. Operator need the higher accuracy machine to maintain the DCC CMM Performance and the consequent of the machine should has better accuracy than the DCC CMM accuracy it self. One of that tool is laser interferometer which has better accuracy than DCC CMM specification and produce the data and can be analyzed for DCC CMM performance. The consistent performance of the DCC CMM is constrained by the errors that brought by the machine error that occurs on a periodic basis on the account of machine usage, machine age and operating temperature. DCC CMM accuracy was compensated and improved by identifying the machine condition. This condition also applicable for predict the machine errors.

scholarly journals Design of a Single-Tooth Model and Its Application in Oral Scan System Assessment

Scanning ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
HongXin Cai ◽  
Bing Cheng Zhao ◽  
Yueyi Tian ◽  
Dong-Hyuck Kim ◽  
Yunhan Sun ◽  
...  
Keyword(s):  
Standard Model ◽  
Reference Model ◽  
Coordinate Measuring Machine ◽  
Intraoral Scanner ◽  
Current Standard ◽  
Integration Model ◽  
Digital Impressions ◽  
Measuring Machine ◽  
Clinically Significant ◽  
Important Position

Intraoral scanners have been widely used in the application of dentistry. Accuracy includes trueness and precision; they have an important position in the assessment of intraoral scanners. The existing standard models are divided into the inlay and the crown, but the operation is relatively complicated. In this study, in order to simplify the current standard model, we designed a new integration model to compare the accuracy of two intraoral scanners (CEREC and TRIOS) and an extraoral scanner (SHINING). The coordinate measuring machine measured value is the gold standard. Values of the length and angle were analyzed by converting the scanned digital impressions into an STL (standard triangulation language) format to evaluate the accuracy of the intraoral scanner and to verify the feasibility of the designed model. The result shows that the integration model can be successfully scanned and imaged. In the case of the powder-free integration model, intraoral scanner precision, trueness, 3D fitting, and imaging are better than the extraoral scanner. It can be seen straightly from the measurement result and the 3D fitting result that the intraoral scanner can acquire the shape of the standard model integrally with good repeatability. Therefore, it can be concluded that TRIOS is superior to CEREC and SHINING in accuracy, and the integration model is feasible as a reference in the examination of intraoral scanners. The performance of the newly designed integration model that can be scanned is clinically significant, suggesting that this model can be used as a standard reference model.

scholarly journals Three-Dimensional Accuracy of Digital Impression versus Conventional Method: Effect of Implant Angulation and Connection Type

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Marzieh Alikhasi ◽  
Hakime Siadat ◽  
Alireza Nasirpour ◽  
Mahya Hasanzade
Keyword(s):  
Reference Model ◽  
Angular Displacement ◽  
Digital Impression ◽  
Angular Distortion ◽  
Data Sets ◽  
Digital Technique ◽  
Direct Technique ◽  
Measuring Machine ◽  
Connection Type

Purpose. The aim of this in vitro study was to compare the accuracy of different implant impression techniques of the maxillary full arch with tilted implants of two connection types. Materials and Methods. Two maxillary edentulous acrylic resin models with two different implant connections (internal or external) served as a reference model. Each model had two anterior straight and two posterior angulated implants. Ninety impressions were made using an intraoral scanner (Trios 3Shape) with scan bodies for digital impression (groups DII and DIE), a custom open tray with additional silicone for the conventional direct group (groups CDI and CDE), and a custom closed tray with additional silicone for the conventional indirect group (groups CII and CIE) from both internal and external models, respectively. A coordinate-measuring machine (CMM) was used to measure linear and angular displacement for conventional specimens. For digital groups, an optical CMM was used to scan the reference model. STL data sets from the digital specimen were superimposed on STL reference data sets to assess angular and linear deviations. Data were analyzed with three-way ANOVA and t-test at α=0.05. Results. There were significant angular and linear distortion differences among three impression groups (P<0.001), angular distortion differences between internal and external connections (P<0.001), and between straight and tilted implants for either linear (P<0.001) or angular (P=0.002) distortion. The type of the connection and implant angle did not have any effect on linear and angular distortion of the digital technique (p>0.05). Minimum angular and linear distortion was seen for tilted implants in DII and DIE groups (0.36° ± 0.37 and 0.16 ± 0.1 mm). Conclusion. Impression techniques (digital versus conventional) affected the transfer accuracy. Digital techniques demonstrated superior outcome in comparison with conventional methods, and the direct technique was better than the indirect conventional technique. Connection type and implant angulation were other factors that influenced accuracy. However, when digital impression was applied, accuracy was not affected by the type of connection and angulation.

Three-Dimensional Accuracy of Implant and Abutment Level Impression Techniques: Effect on Marginal Discrepancy

2011 ◽  
Vol 37 (6) ◽  
pp. 649-657 ◽  
Author(s):  
Marzieh Alikhasi ◽  
Hakimeh Siadat ◽  
Abbas Monzavi ◽  
Fatemeh Momen-Heravi
Keyword(s):  
Angular Displacement ◽  
Angular Position ◽  
Three Dimensional ◽  
Coordinate Measuring Machine ◽  
Dimensional Accuracy ◽  
Acrylic Resin ◽  
Positional Accuracy ◽  
Type Iv ◽  
Marginal Discrepancy ◽  
Measuring Machine

Impression techniques should precisely represent the 3-dimensional status of implants to allow for the fabrication of passively fitting prostheses and subsequently the elimination of strain on supporting implant components and surrounding bone. The aim of this study was to compare the accuracy of an abutment level impression method with that of an implant level (direct and indirect) impression method using polyether impression material to obtain precise definitive casts and prostheses. A reference acrylic resin dentoform with 2 internal connection implants (Implantium) was made. A total of 21 medium-consistency polyether impressions of the dentoform, including 7 direct implant level, 7 indirect implant level, and 7 abutment level (after 2 straight abutments were secured), were made. Impressions were poured with American Dental Association (ADA) type IV stone, and the positional accuracy of the implant replica heads and abutment analogs in each dimension of x-, y-, and z-axes, as well as angular displacement (Δθ), was evaluated using a coordinate measuring machine. Noble alloy 3-unit castings were fabricated and seated on the abutments in 3 groups; marginal discrepancies were measured at 4 points between prostheses and abutments. Data were analyzed using Mann-Whitney U test, 1-way analysis of variance (ANOVA), and Kruskal-Wallis tests. In comparisons of different impression techniques, only significant statistical Δθ differences were noted between the abutment level method and other techniques (P &lt; .001). Results of this study reveal that although the implant level impression method could better transfer the angular position of the implants (Δθ), the impression method could not affect Δy, Δx, and Δz coordinates of the implants or marginal discrepancy of the 3-unit fixed partial dentures (FPD).

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