In vitro study about the abutment axial wall’s convergence

2020 ◽  
Vol 3 (1) ◽  
pp. 269-274
Author(s):  
Diana Cerghizan ◽  
Adriana Crăciun ◽  
Aurița Albu ◽  
Monica Baloș ◽  
Kinga Mária Jánosi
Keyword(s):  
In Vitro Study ◽  
Dental Students ◽  
Practical Skills ◽  
Or Education ◽  
Dental Practitioners ◽  
Significant Difference ◽  
Low Visibility ◽  
Tooth Preparation ◽  
Working Day

AbstractIntroduction: The total convergence of the axial walls is the angle made between the opposing axial walls of an abutment. The lower the taper value, the better the retention of the crowns is. Obtaining a proper convergence of the axial wall is a challenge for dental practitioners due to limited access and low visibility, but it also greatly depends on the clinician’s practical skills.This study aims to compare the total convergence of axial walls obtained after tooth preparation done by different experience practitioners in various positions of the patient and different working time (different days of the week, various parts of the day).Materials and methods: To perform this study, 40 acrylate model teeth have been prepared by two last year dental students and two prosthetists. All of them performed two teeth preparations per day in every working day of a week. All the prepared teeth have been photographed, and digitally measured.Results: The extremely statistically significant difference was found in the two beginners’ case, the values of the second beginner being much higher, as in the two experienced operators, where the values are higher for the second prosthetist.Conclusion: The total convergence of the axial wall did not depend on the operators’ experience or education level.

scholarly journals Feasibility of 3-Dimensional Visual Guides for Preparing Pediatric Zirconia Crowns: An In Vitro Study

2020 ◽  
Vol 17 (16) ◽  
pp. 5732
Author(s):  
Ho Yeon Kang ◽  
Hyeonjong Lee ◽  
Yong Kwon Chae ◽  
Seoung-Jin Hong ◽  
Yun Yeong Jeong ◽  
...  
Keyword(s):  
Three Dimensional ◽  
In Vitro Study ◽  
Mixed Dentition ◽  
Preparation Time ◽  
Second Molar ◽  
Significant Difference ◽  
Distal Surface ◽  
Zirconia Crowns ◽  
Tooth Preparation

This study evaluated the feasibility of a tooth preparation guide for prefabricated zirconia crowns (PZCs). Three-dimensional surface data for PZCs of the left maxillary primary first molar and left mandibular primary second molar were obtained using a model scanner. The tooth preparation data were digitally designed to harmonize with the adjacent teeth on the mixed dentition model and visualized using a color-coded map, which presents the required amount of tooth reduction. Twenty participants were recruited for preparing teeth with and without using the tooth preparation guide. The following three parameters were evaluated: tooth preparation time, harmony score, and amount of tooth reduction. The preparation time when using the guide was significantly reduced (p < 0.05), and a significant difference was observed in the harmony scores for the maxillary primary first molar preparation. Furthermore, the amount of tooth reduction was significantly different for both maxillary and mandibular primary molars (p < 0.05) in terms of the occlusal distal surface and buccal line angle in the maxillary primary first molars, and the smooth surfaces, proximal surfaces, and mesial line angles in the mandibular primary second molars. Thus, the results suggest that a tooth preparation guide could facilitate better tooth preparation for PZCs.

A Comparative in vitro Study of the Load at Fracture of All-ceramic Crowns with Various Thicknesses of In-Ceram Core

2008 ◽  
Vol 9 (4) ◽  
pp. 17-25 ◽  
Author(s):  
Ilser Turkyilmaz ◽  
Suat Gokce ◽  
Emine Celik-Bagci
Keyword(s):  
Fracture Resistance ◽  
Testing Machine ◽  
In Vitro Study ◽  
Chromium Alloy ◽  
Dental Practitioners ◽  
Significant Difference ◽  
All Ceramic ◽  
Feasible Option ◽  
Ceramic Crowns

Abstract Aim The aim of this study was to investigate the influence of three different thicknesses of In-Ceram core on the load at fracture of all-ceramic crowns. Methods and Materials Thirty standardized crown-shaped nickel-chromium alloy dies were fabricated using a milling machine. Twenty dies were prepared with a 1 mm shoulder for Groups A and B. The only difference in the ten dies used for Group C was a smaller 0.5 mm lingual shoulder. The thicknesses of In-Ceram were 0.5 mm, 1.5 mm, and 0.75 mm for Groups A, B, and C. All all-ceramic crowns were fabricated in accordance with the manufacturer's instructions. After cementation of the crowns, their fracture resistance was tested with a universal testing machine. The load was directed to a point located 3 mm from the lingual aspect of the incisal edge at 30 degrees to the long axis of each specimen until catastrophic failure occurred. Results The mean loads at fracture for Groups A, B, and C were 1117±388 N, 2083±385 N, and 1439±368 N, respectively. No statistically significant difference in load at fracture between Groups A and C was found (p>0.05). However, the differences were statistically significant between Groups A and B (p<0.001) and Groups B and C (p<0.001). Conclusion Under the guidelines of this study, increasing the thickness of the In-Ceram core increased the fracture resistance of the all-ceramic crowns. Clinical Significance The sufficient thickness of the In-Ceram core of all-ceramic crowns is an important factor in fracture resistance. Therefore, dental practitioners should be careful in patient selection; if the horizontal overlap of a tooth to be restored is too limited, then all-ceramic crowns may not be a feasible option. Citation Gokce S, Celik-Bagci E, Turkyilmaz I. A Comparative in vitro Study of the Load at Fracture of Allceramic Crowns with Various Thicknesses of In-Ceram Core. J Contemp Dent Pract 2008 May; (9)4:017-025.

scholarly journals Effect of Different Software Programs on the Accuracy of Dental Scanner Using Three-Dimensional Analysis

2021 ◽  
Vol 18 (16) ◽  
pp. 8449
Author(s):  
Keunbada Son ◽  
Wan-Sun Lee ◽  
Kyu-Bok Lee
Keyword(s):  
Reference Model ◽  
Three Dimensional ◽  
In Vitro Study ◽  
3D Analysis ◽  
Analysis Software ◽  
Test Models ◽  
Significant Difference ◽  
Tooth Preparation ◽  
Software Programs

This in vitro study aimed to evaluate the 3D analysis for complete arch, half arch, and tooth preparation region by using four analysis software programs. The CAD reference model (CRM; N = 1 per region) and CAD test models (CTMs; N = 20 per software) of complete arch, half arch, and tooth preparation were obtained by using scanners. For both CRM and CTMs, mesh data other than the same area were deleted. For 3D analysis, four analysis software programs (Geomagic control X, GOM Inspect, Cloudcompare, and Materialise 3-matic) were used in the alignment of CRM and CTMs as well as in the 3D comparison. Root mean square (RMS) was regarded as the result of the 3D comparison. One-way analysis of variance and Tukey honestly significant difference tests were performed for statistical comparison of four analysis software programs (α = 0.05). In half-arch and tooth preparation region, the four analysis software programs showed a significant difference in RMS values (p < 0.001), but in complete-arch region, no significant difference was found among the four software programs (p = 0.139). As the area of the virtual cast for 3D analysis becomes smaller, variable results are obtained depending on the software program used, and the difference in results among software programs are not considered in the 3D analysis for complete-arch region.

scholarly journals COMPARATIVE EVALUATION OF IATROGENIC DAMAGE IN CLASS II CAVITIES USING MAGNIFICATION TOOLS DURING TOOTH PREPARATION: AN IN VITRO STUDY

2020 ◽  
Vol 8 (11) ◽  
pp. 569-575
Author(s):  
Pooja Yadav ◽  
◽  
Ashish Jain ◽  
Rahul Rao ◽  
Harshil Patel ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Class Ii ◽  
Vitro Study ◽  
Tooth Surface ◽  
Naked Eye ◽  
Significant Difference ◽  
Iatrogenic Damage ◽  
Tooth Preparation ◽  
Post Hoc

Aims: This is an vitro study compares and evaluates the effect of magnification tools on frequency and extent of iatrogenic damage to approximal tooth surface during conservative Class II cavity preparations. Methods and Material: 30 Typodont teeth were divided into 3 groups 10 typodont teeth in each group and were mounted on Phantom head. Teeth were prepared for class II (MO) cavity on 36 with conservative design using airotor with naked eye, loupes and microscope and iatrogenic damage was assessed on tooth no 35. Assessment of iatrogenic damage of all the groups was done by profilometer test. Statistical analysis used:Statistical analysis was done using one-way analysis of variance (ANOVA). Post-hoc pair-wise comparisons were done using Dunnetts test. Results: Results revealed that tooth preparation was better under microscopes and loupes with statistical significant difference for samples with loupes and microscope on comparison with naked eye. Study also expressed the difficulty faced during tooth preparation with microscope and loupes for the first time. Conclusions: Magnifying tools helps in better vision and less iatrogenic damage while preparing the tooth for restoration.

Comparative Study to Evaluate the Surface Detail Reproduction of Dental Stone after Immersion in Various Different Disinfectant Solutions, Under Stereomicroscope 10 X Magnification –An In-Vitro Study

2017 ◽  
Vol 9 (3) ◽  
Author(s):  
Rathika Rai ◽  
M. A. Easwaran ◽  
K. T. Dhivya
Keyword(s):  
Sodium Hypochlorite ◽  
In Vitro Study ◽  
Control Group ◽  
Immersion Method ◽  
Significant Difference ◽  
Surface Irregularities ◽  
Disinfectant Solution ◽  
Surface Detail ◽  
Group B

Aim: To evaluate the surface detail reproduction of dental stone this is immersed in different disinfectant solution and studied under stereomicroscope. Methodology: Total number of 30 specimens of dental stone (Type III) were made with measurements of 1.5cm diameter and 1cm height .This samples are divided in to 3 groups group A,B,C. were A is immersed in Distilled water which was taken as control group ;B is immersed in 2% Glutaraldehyde and C is immersed in 5%sodium hypochlorite. Each specimen were immersed in the disinfectant solution for 15 minutes and dried under room temperature for 24 hrs. After 24 hrs each specimens are studied under stereomicroscope for surface details. Result: The results showed no significant difference in the surface irregularities and porosities for a group 1 and group 2 except group 3 which showed significant increase in the porosities, surface irregularities and erosions after disinfection with 5% NaHOCl by immersion method. Conclusion: The surface detail reproduction capacity of die stone was adversely affected when 5% Sodium hypochlorite was used as disinfectant solution when compare d to control group and 2% Glutaraldehyde

scholarly journals Diagnostic Accuracy of Oral Cancer and Suspicious Malignant Mucosal Changes among Future Dentists

Healthcare ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 263
Author(s):  
Kamis Gaballah ◽  
Asmaa Faden ◽  
Fatima Jassem Fakih ◽  
Anfal Yousuf Alsaadi ◽  
Nadeen Faiz Noshi ◽  
...  
Keyword(s):  
Oral Cancer ◽  
Dental Students ◽  
Benign Tumors ◽  
Dental Practitioners ◽  
Significant Difference ◽  
Potentially Malignant Disorders ◽  
Potentially Malignant ◽  
Recent Graduates ◽  
Mucosal Changes ◽  
Oral Abnormalities

This study aimed to assess the ability of dental students and recent graduates to detect and recognize mucosal changes that are suggestive of oral cancer and potentially malignant disorders. In this cross-sectional study, a questionnaire was administered to dental students and recent graduates of Ajman University (n = 132). Completed questionnaires were received from 84 (63.6%) females and 48 (36.4%) males which included fifth-year students (n = 80), interns (n = 39), and dental practitioners (n = 13). This questionnaire was designed to assess the respondent’s ability to detect and recognize different types of oral lesions, as well as their knowledge of oral cancer appearance and malignancy potential. The overall accuracy of diagnosis was 46%. The participants correctly identified normal variations, benign tumors, malignant tumors, and premalignant lesions at rates of 60.3%, 31.0%, 55.7%, and 33.4%, respectively. There was no significant difference between the two genders in their ability to recognize and detect correct answers (females, 48.3%; males, 47.2%). According to education level, interns provided the highest percentage of correct answers (52.5%), followed by newly dental practitioners (51.9%) and fifth-year students (44.1%). Conclusion: The respondents of this survey did not exhibit a satisfactory diagnostic capability in recognizing mucosal changes consistent with the clinical presentation of oral cancer. Thus, a need exists for improved and updated educational methods for undergraduate students regarding oral cancer and potentially malignant disorders. Meanwhile, practitioners should look for oral abnormalities to provide better diagnosis and management. Practitioners should also stay up to date on the oral malignancy topic by attending workshops and clinicopathological conferences.

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.

scholarly journals In vitro study of human osteoblast proliferation and morphology on orthodontic mini-implants

2015 ◽  
Vol 85 (6) ◽  
pp. 920-926 ◽  
Author(s):  
Ricardo Carvalho Bueno ◽  
Roberta Tarkany Basting
Keyword(s):  
Chemical Composition ◽  
In Vitro Study ◽  
Chemical Components ◽  
Control Group ◽  
Osteoblast Proliferation ◽  
Mini Implants ◽  
Significant Difference ◽  
Implant Anchorage ◽  
Positive Effect

ABSTRACT Objective:  To evaluate the proliferation and morphology of human osteoblasts cultured on two brands of mini-implants after 24, 48, and 72 hours, in addition to the chemical composition found on their surface. Materials and Methods:  Two brands of mini-implant (Morelli and Neodent) were evaluated; polystyrene was used as a control group (n  =  3). Osteoblasts were cultured on the surface of sterilized mini-implants in a CO2 incubator at different time periods (24, 48, and 72 hours). Osteoblast proliferation was quantified by scanning electron microscopy using up to 5000× magnification, and cell morphology was analyzed by a single observer. For the chemical analysis, spectroscopy X-ray fluorescence was used to identify and quantify chemical components on the surface of the mini-implants. Results:  Two-way ANOVA showed no significant interaction between the factors studied (P  =  0.686). A Tukey test revealed no significant difference in osteoblast proliferation between the mini-implants at all studied periods; however, a difference in cell proliferation was detected between the Neodent and the control group (P  =  .025). For all groups, time had a direct and positive effect on osteoblast proliferation (P &lt; .001). The significant elements present in both brands of mini-implants were titanium, aluminum, vanadium, and iron. Conclusions:  Osteoblast proliferation was present on the mini-implants studied, which increased over time; however, no significant difference between brands was observed. No difference was seen between the mini-implants evaluated in terms of chemical composition. Cell adhesion after 72 hours suggests that areas of bone remodeling can be achieved, thus initiating the process of mini-implant anchorage.

A novel intracranial exchange guidewire improves the navigation of various endovascular devices: An in vitro study of challenging situations

2021 ◽  
pp. 159101992110573
Author(s):  
Naoki Kaneko ◽  
Ariel Takayanagi ◽  
Hamidreza Saber ◽  
Lea Guo ◽  
Satoshi Tateshima
Keyword(s):  
Giant Aneurysm ◽  
In Vitro Study ◽  
Target Vessel ◽  
Success Rates ◽  
Intracranial Stenting ◽  
Aneurysm Neck ◽  
Significant Difference ◽  
Aneurysm Model ◽  
Endovascular Devices

Objective Neuroendovascular procedures rely on successful navigation and stable access to the target vessel. The Stabilizer is a 300 cm long exchange wire with a 0.014 diameter and a soft, flexible stent at the distal end designed to assist with navigation and device delivery. This study aims to assess the efficacy of the Stabilizer for navigation in a variety of challenging environments. Methods The efficacy of the Stabilizer was evaluated using three challenging vascular models: a giant aneurysm model, a severe tortuosity model, and an M1 stenosis model. The Stabilizer was compared with a conventional wire during navigation in each model. Results In the giant aneurysm model, there was no significant difference of success during straightening of a looped wire and significantly higher success rates when advancing an intermediate catheter with the Stabilizer beyond the aneurysm neck compared to a conventional guidewire. The Stabilizer also significantly increased success rates when advancing an intermediate catheter through a model with severe tortuosity compared to a conventional guidewire, as well as exchange maneuver for intracranial stenting in a stenosis model compared to an exchange wire. Conclusions In our experimental model, the Stabilizer significantly improved navigation and device delivery in a variety of challenging settings compared to conventional wires.

scholarly journals The Antibacterial Efficacy of Biopure MTAD in Root Canal Contaminated with Enterococcus faecalis

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Blerim Kamberi ◽  
Donika Bajrami ◽  
Miranda Stavileci ◽  
Shuhreta Omeragiq ◽  
Fatmir Dragidella ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Sodium Hypochlorite Solution ◽  
Antibacterial Efficacy ◽  
Human Teeth ◽  
Exact Test ◽  
Hypochlorite Solution ◽  
Root Canals ◽  
Significant Difference ◽  
Level Of Significance

Aim. The purpose of this in vitro study was to assess the antimicrobial efficacy of Biopure MTAD against E. faecalis in contaminated root canals. Materials and Methods. Forty-two single rooted extracted human teeth were inoculated with E. faecalis and incubated for four weeks. The samples were divided in two control and five experimental groups irrigated with 1.5% sodium hypochlorite solution (NaOCl); 3% NaOCl; BioPure MTAD; 1.5% NaOCl/17% EDTA; or 3% NaOCl/17% EDTA. After a one-week incubation, complete disinfection was confirmed by the absence of turbidity in the incubation media. Dentin shavings were taken from samples with no turbidity to verify whether E. faecalis was present in dentin tubules. Results were analyzed statistically using Fisher's exact test, with the level of significance set at . Results. Statistical analysis of the data obtained at Day 7 and after dentin shaving analysis showed that BioPure MTAD had significantly greater antibacterial activity than 1.5% NaOCl, 1.5% NaOCl/17% EDTA and 3% NaOCl/17% EDTA. No significant difference was detected between MTAD and 3% NaOCl. Conclusions. These findings suggest that BioPure MTAD possesses superior bactericidal activity compared with NaOCl and EDTA against E. faecalis.

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