scholarly journals The impact of impression coping geometrical design on accuracy of implant impressions: an experimental study

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Motaz Osman ◽  
Neamat Hassan Abubakr ◽  
Ahmed Suliman ◽  
Hassan Ziada
Keyword(s):  
Experimental Study ◽  
In Vitro Study ◽  
Acrylic Resin ◽  
Vitro Study ◽  
Geometrical Design ◽  
Custom Made ◽  
Significant Difference ◽  
The Impact

Abstract Aim This in vitro study aimed to evaluate the effect of implant impression coping geometrical designs on the accuracy of open and closed impression techniques and in the parallel and nonparallel implant positions. Material and methods Three custom-made acrylic resin models of three tested implant systems (Straumann®, SIC Invent®, and Osstem®) with diverse coping geometrical designs were evaluated in simulated cases of two parallel and two nonparallel implants. The horizontal and vertical discrepancies were measured and analyzed. Results No statistically significant differences between the two impression techniques in either parallel or nonparallel implants were observed. The high retentive design of the Osstem system showed a statistically significant difference. Conclusion The geometrical design of the impression copings did not affect the accuracy for either the open and closed tray techniques. However, the high retentive coping design of the Osstem implant affected the accuracy in the open tray technique.

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 < .01) and also among the 3 different techniques (P < .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 < .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 IN VITRO STUDY ON MARGINAL MICROLEAKAGE OF FOUR TEMPORARY CEMENTS IN PROVISIONAL CROWNS

2019 ◽  
Vol 3 (8) ◽  
Author(s):  
Dr. Ravi Nag ◽  
Dr. Jagjeet Singh ◽  
Dr. Abhilasha Masih Gottlieb ◽  
Dr. Ponnanna A. A. ◽  
Dr. Nikhil Verma ◽  
...  
Keyword(s):  
Zinc Phosphate ◽  
In Vitro Study ◽  
Acrylic Resin ◽  
Vitro Study ◽  
P Value ◽  
Chi Square ◽  
Human Teeth ◽  
Luting Cement ◽  
Significant Difference

Background: Prolonged retention of provisional restoration is depends upon the long term affinity between restoration and teeth structures which depend upon the use of good mechanical characteristics, low solubility, and superior adhesion  quality of luting cement which also resist bacterial and molecular penetration. Hence, assessment of marginal leakage of provisional restorative materials sealed with provisional cements using the standardized procedures is essential. Aim: This study aimed at in vitro study of microleakage of 4 provisional cements, a cavity base compound and a zinc-phosphate luting cement in provisional acrylic resin crowns fixed on extracted human teeth. Material & Methods:  The teeth with acrylic restorations were randomly divided into 6 groups of 6 specimens each. Each group received different types of temporary cement. Acrylic resin crowns were made and fitted on intact human premolars with the 4 cements. All restorations were applied in a standardized manner. Specimen were submerged in a 2% methylene blue solution, then sectioned and observed under a stereomicroscope for the detection of marginal microleakage. Obtained data were subjected to ANNOVA and Chi –square test to know statistical significant difference between different groups.  P value less than 0.05 was considered significant. Results and observation: Mean frequency of microleakage was statistically significant among all the groups under study with Pvalue<0.017. Conclusion: Among all the temporary cement, Zinc-phosphate cements has the best property with reduced microleakage. Even it is used as cavity base but can be used as good temporary cement as far as microleakage is concerned. Key words, Microleakage, provisional cement, restorations, crowns, in vitro

scholarly journals Heat Generation and Temperature Control during Bone Drilling for Orthodontic Mini-Implants: An In Vitro Study

2021 ◽  
Vol 11 (16) ◽  
pp. 7689
Author(s):  
Ibrahim Barrak ◽  
Gábor Braunitzer ◽  
József Piffkó ◽  
Emil Segatto
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Fluid Temperature ◽  
Drilling Speed ◽  
Temperature Changes ◽  
Irrigation Fluid ◽  
Pilot Hole ◽  
Significant Difference ◽  
The Impact

Background: The purpose of our in vitro study was to evaluate the impact of different irrigation fluid temperatures in combination with different drilling speeds on intraosseous temperature changes during mini-implant site preparation. Methods: Porcine ribs were used as bone specimens. Grouping determinants were as follows: irrigation fluid temperature (10 and 20 °C) and drilling speed (200, 600, 900, and 1200 RPM). The axial load was controlled at 2.0 kg. Temperature measurements were conducted using K-type thermocouples. Results: Extreme increments were observed only in the unirrigated groups. Irrigation invariably made a significant difference within groups defined by the same drilling speed. The comparison of the different temperature irrigation fluids (10 and 20 °C) in combination with the same drilling speed (200, 600, 900, or 1200 rpm) resulted in a statistically significant difference between the two different temperatures, whereas the use of irrigation fluid at a controlled room temperature of 20 °C showed significantly higher temperature changes. Conclusions: Based on the results of the study, we conclude that irrigation while preparing a pilot hole for a self-tapping orthodontic miniscrew is of utmost importance, even at low drilling speeds. The temperature of the cooling fluid does influence local temperature elevation to a significant extent.

Effect of the Incorporation of Chitosan and TiO2 Nanoparticles on the Shear Bond Strength of an Orthodontic Adhesive: An In Vitro Study

2021 ◽  
pp. 232020682110154
Author(s):  
Fahimeh Farzanegan ◽  
Hooman Shafaee ◽  
Majid Darroudi ◽  
Abdolrasoul Rangrazi
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Chitosan Nanoparticles ◽  
In Vitro Study ◽  
Acrylic Resin ◽  
Vitro Study ◽  
Group 4 ◽  
Significant Difference

Aim: This in vitro study was aimed to evaluate the effect of adding different concentrations of chitosan nanoparticles (NPs) and TiO2 NPs on the shear bond strength (SBS) of an orthodontic adhesive. Materials and Methods: In this in vitro study, 72 extracted human premolars were embedded in an acrylic resin and randomly allocated into four groups of 18 specimens. In group 1 (control), brackets were bonded to the tooth with the Transbond XT orthodontic adhesive. In groups 2, 3, and 4, 0.5% chitosan NPs and 0.5% TiO2 NPs, 1% chitosan NPs and 1% TiO2 NPs, and 1.5% chitosan NPs and 1.5% TiO2 NPs were added to Transbond XT, respectively. Then, the brackets were bonded by the modified adhesive. The SBS and adhesive remnant index (ARI) of each group were assessed with a universal testing machine. The SBS test results were analyzed using one-way analysis of variance followed by the posthoc Tukey’s honestly significant difference (HSD) test. The Kruskal–Wallis test was also applied to evaluate the ARI scores. Results: The results showed no statistically significant difference between groups 1, 2, and 3, but SBS decreased significantly in group 4. With increasing the concentration of NPs up to 1% chitosan NPs and 1% TiO2 NPs, SBS did not change significantly. However, in 1.5% chitosan NPs and 1.5% TiO2 NPs, SBS decreased compared to the other three groups. No significant differences were found between the groups in terms of ARI scores. Conclusion: It is concluded that the orthodontic composite containing 1% chitosan NPs and 1% TiO2 NPs has adequate SBS for use in the clinical setting.

scholarly journals Marginal and Internal Fit of Ceramic Prostheses Fabricated from Different Chairside CAD/CAM Systems: An In Vitro Study

2021 ◽  
Vol 11 (2) ◽  
pp. 857
Author(s):  
Keunbada Son ◽  
Kyu-Bok Lee
Keyword(s):  
Computer Aided Design ◽  
In Vitro Study ◽  
Vitro Study ◽  
Marginal Gap ◽  
Significant Difference ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Internal Fit ◽  
Cam Systems

The purpose of this in vitro study was to evaluate marginal and internal fits of ceramic crowns fabricated with chairside computer-aided design and manufacturing (CAD/CAM) systems. An experimental model based on ISO 12836:2015 was digitally scanned with different intraoral scanners (Omnicam (CEREC), EZIS PO (DDS), and CS3500 (Carestream)). Ceramic crowns were fabricated using the CAD/CAM process recommended by each system (CEREC, EZIS, and Carestream systems; N = 15). The 3-dimensional (3D) marginal and internal fit of each ceramic crown was measured using a 3D inspection software (Geomagic control X). Differences among the systems and various measurements were evaluated using the Kruskal–Wallis test. Statistically significant differences were validated using pairwise comparisons (α = 0.05). Occlusal gaps in the CEREC, EZIS, and Carestream groups were 113.0, 161.3, and 438.2 µm, respectively (p < 0.001). The axial gaps were 83.4, 78.0, and 107.9 µm, respectively. The marginal gaps were 77.8, 99.3, and 60.6 µm, respectively, and the whole gaps were 85.9, 107.3, and 214.0 µm, respectively. Significant differences were observed with the EZIS system compared with the other two systems in terms of the marginal gap sizes. The CEREC system showed no significant differences among the four measured regions. However, the EZIS and Carestream systems did show a statistically significant difference (p < 0.05). All three systems were judged to be capable of fabricating clinically acceptable prostheses, because the marginal gap, which is the most important factor in the marginal fit of prostheses, was recorded to be below 100 µm in all three systems.

Behavior of implant and abutment sets of three different connections during the non-axial load application: An in vitro experimental study using a radiographic method

2021 ◽  
pp. 1-12
Author(s):  
Sergio Alexandre Gehrke ◽  
Berenice Anina Dedavid ◽  
José Manuel Granero Marín ◽  
Luigi Canullo
Keyword(s):  
Experimental Study ◽  
Digital Radiography ◽  
Axial Load ◽  
In Vitro Study ◽  
Vitro Study ◽  
Load Application ◽  
Radiographic Method ◽  
Radiography System ◽  
Torque Values

BACKGROUND: During the masticatory cycle, loads of different intensities and directions are received by the dental structures and/or implants, which can cause micromovements at the junction between the abutment and implant. OBJECTIVE: The objective of this in vitro study was to evaluate the behavior of three different implant connections subjected to different load values using a digital radiography system. Additionally, the torque values for removing the abutment screws were also measured and compared. METHODS: Ninety sets of implant and abutment (IA) were used, divided into three groups according to the type of connection (n = 30 per group): EH group, external hexagon type connection; IH group, internal hexagon connection; and, MT group, Morse taper connection. RESULTS: MT group showed the better vertical misfit behavior at the three intensity of load applied, in comparison with EH and IH groups. In the analysis of torque maintenance (detorque test), MT group showed higher values of detorque when compared with the measured values of EH and IH groups (p < 0.001). CONCLUSIONS: The IA sets of EH and IH groups showed a microgap in all levels of applied loads, unlike the MT group this event was not observed. In the detorque test, MT group increase in the torque values when compared to the initial torque applied, unlike EH and IH groups showed a decrease in the initially torque applied in all conditions tested. A positive correlation was detected between the misfit and detorque values.

The impact of stent design on the structural mechanics of the crossing Y-stent: an in vitro study

2014 ◽  
Vol 56 (8) ◽  
pp. 655-659 ◽  
Author(s):  
Chang-Young Lee ◽  
Seong-Ho Park ◽  
Chang-Hyun Kim ◽  
Goetz Benndorf
Keyword(s):  
In Vitro Study ◽  
Structural Mechanics ◽  
Vitro Study ◽  
Stent Design ◽  
The Impact

scholarly journals THE EFFECT OF CURCUMA XANTHORRHIZA ETHANOL EXTRACT ON THE VIABILITY OF STREPTOCOCCUS MUTANS AND AGGREGATIBACTER ACTINOMYCETEMCOMITANS (DENTAL BIOFILM RESEARCH: IN VITRO STUDY)

2017 ◽  
Vol 10 (17) ◽  
pp. 30
Author(s):  
Royan Diana ◽  
Hedijanti Joenoes ◽  
Ariadna A Djais
Keyword(s):  
Streptococcus Mutans ◽  
In Vitro Study ◽  
Ethanol Extract ◽  
Single Species ◽  
Aggregatibacter Actinomycetemcomitans ◽  
Vitro Study ◽  
Dental Biofilm ◽  
Significant Difference ◽  
Curcuma Xanthorrhiza

Objective: This study aimed to compare the effect of Curcuma xanthrorrhiza ethanol extract to the viability of Streptococcus mutans and Aggregatibacter  actinomycetemcomitans using single- and dual-species biofilm at different phases of formation.Methods: Biofilm models were incubated for 4, 12, and 24 hrs, then exposed to the extract at a concentration of 0.525%.Results: The viability of the single-species S. mutans biofilm was low (p<0.05), and no significant difference (p>0.05) was found between singlespeciesA. actinomycetemcomitans and dual-species biofilm.Conclusions: Curcuma xanthorrhiza ethanol extract is more effective for decreasing the viability of single-species S. mutans biofilm.

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