scholarly journals Comparative Evaluation of Adaptation of Esthetic Prefabricated Fiberglass and CAD/CAM Crowns for Primary Teeth: Microcomputed Tomography Analysis

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Ece Irem Oguz ◽  
Tuğba Bezgin ◽  
Ayse Isıl Orhan ◽  
Kaan Orhan
Keyword(s):  
Clinical Success ◽  
Three Dimensional ◽  
Repeated Measure ◽  
Linear Measurements ◽  
Factorial Anova ◽  
Mandibular Molar ◽  
Significant Difference ◽  
Cad Cam ◽  
Ceramic Blocks ◽  
Molar Teeth

Adaptation is an important factor for the clinical success of restorations. However, no studies are available evaluating the adaptation of primary crowns. The aim of this study was to compare the adaptation of crowns fabricated by CAD/CAM technology versus prefabricated fiberglass primary crowns. Typodont maxillary central, canine, and mandibular molar teeth were prepared to serve as master dies after the size of Figaro crowns was determined ( n = 10 ). Master dies were scanned with an intraoral scanner, and 10 identical CAD/CAM crowns were fabricated from resin-ceramic blocks. Figaro and CAD/CAM crowns were placed on the corresponding master dies and scanned via micro-CT. Three-dimensional volumetric gap measurements were performed to evaluate the overall adaptation. A total of 255 location-based linear measurements were allocated into 4 categories: marginal, cervical-axial, middle-axial, and occlusal. Statistical analyses were performed with factorial ANOVA, repeated measure ANOVA, and LSD tests ( α = 0.05 ). CAD/CAM crowns showed significantly lower overall and location-based gap measurements than Figaro crowns regardless of tooth number ( p < 0.05 ). For all groups, mean marginal discrepancies were lower than occlusal measurements ( p < 0.05 ). Both crown types showed higher marginal gaps for molar teeth than for canine and central incisors with no significant difference between them ( p > 0.05 ). CAD/CAM-fabricated crowns showed better marginal and internal adaptation than prefabricated Figaro crowns.

scholarly journals A Clinical and Radiographic Assessment of Sodium Hypochlorite Versus Formocresol Pulpotomy in Primary Molar Teeth: 12-month Follow-up.

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Zahra Bahrololoomi ◽  
Fatemeh Zarebidoki ◽  
Atefeh Shakib
Keyword(s):  
Root Resorption ◽  
Clinical Success ◽  
Primary Molars ◽  
Pathologic Finding ◽  
Success Rates ◽  
Primary Molar ◽  
Exact Test ◽  
Significant Difference ◽  
Molar Teeth

Objective: The aim of this study was to compare the clinical and radiographic success rates of pulpotomy in primary molars using formocresol versus sodium hypochlorite.Methods:  Twenty-three children aged 4-9 years with at least two primary molars requiring pulpotomy were randomly allocated into two groups. All teeth received stainless steel crown after conventional pulpotomy procedure with either NaOCl or formocresol. Clinical and radiographic signs/symptoms were recorded at six and 12 months. Outcomes were statistically analyzed using Fisher’s exact test and Chi-squaretest.Results: Clinical success rates at 6 and 12-month follow-up in both groups was 100%. At 6-month follow-up, radiographic success rate for NaOCl and formocresol groups was 100%. At 12-month recalls, in NaOCl group, 20 teeth (87%) and in formocresol group, 21 teeth (91.3%) had radiographic success. No significant difference was found in the radiographic success rates at 12 months (P=1.00). Internal root resorption was the most common radiographic pathologic finding in both groups.Conclusion:Clinical and radiographic success rates in NaOCl group was comparable with formocresol group, so NaOCL can be suggested as an alternative for primary teeth pulpotomies. However further clinical studies with long-term follow-ups are needed. 

scholarly journals Effectiveness of Ozone with or without the Additional Use of Remineralizing Solution on Non-Cavitated Fissure Carious Lesions in Permanent Molars

2011 ◽  
Vol 05 (04) ◽  
pp. 393-399 ◽  
Author(s):  
Didem Atabek ◽  
Nurhan Oztas
Keyword(s):  
Wilcoxon Test ◽  
Clinical Severity ◽  
Ozone Treatment ◽  
Carious Lesions ◽  
Mandibular Molar ◽  
Significant Difference ◽  
Molar Teeth ◽  
Permanent Molars ◽  
Dependent Samples ◽  
Caries Lesions

ABSTRACTObjectives: The aim of this study was to evaluate the efficiency of ozone alone and with a re-mineralizing solution following application on initial pit and fissure caries lesions in permanent molars. Methods: Forty children (9-12 years) having non-cavitated fissure caries lesions on bilateral 40 first permanent mandibular molar teeth were participated in the study. Patients were randomly allocated to 2 experimental groups consisting of 20 subjects. In the first group, ozone was applied once for 40 seconds to the assigned test teeth of each pair. In the second group, ozone was applied once for 40 seconds to the assigned test teeth of each pair with the use of re-mineralizing solution. Progression or improvement of the caries was assessed at baseline, immediately after treatment and at 1-,2-,3-, and 6 month follow-up by comparing the DIAGNOdent values, Clinical Severity Indexes, Oral Hygiene Scores. The results were analyzed statistically by using the Wilcoxon-Test for dependent samples in each group. When comparing different test groups (control and experimental groups) the Friedman S test followed by the Mann-Whitney U test was used. Results: A statistically significant difference was found between all of the control and experimental test lesions in each group (P<.001). However, there was no statistically significant difference between the ozone treated groups and those using the additional re-mineralizing solution (P>.001). Conclusions: Ozone treatment either alone or combined with a re-mineralizing solution was found to be effective for remineralization of initial fissure caries lesions. (Eur J Dent 2011;5:393-399)

scholarly journals Influence of drying time of adhesive systems on the bond strength between resin cement and feldspathic ceramic

2016 ◽  
Vol 19 (1) ◽  
pp. 88
Author(s):  
Sabrina Alves Feitosa ◽  
Isabela Gomes Moura ◽  
Pedro Henrique Corazza ◽  
Cesar Dalmolin Bergolli ◽  
Clóvis Pagani ◽  
...  
Keyword(s):  
Bond Strength ◽  
Adhesive System ◽  
Resin Cement ◽  
Ceramic Surface ◽  
Drying Time ◽  
Ceramic Block ◽  
Significant Difference ◽  
Before And After ◽  
Cad Cam ◽  
Ceramic Blocks

<p><strong>O</strong><span lang="en-US"><strong>bjective: </strong></span><span lang="en-US">This study evaluated the effect of drying times of two total-etch &amp; rinse adhesives on the resin bond strength to a feldsphatic ceramic, before and after aging. </span><span lang="en-US"><strong>Material and Methods: </strong></span><span lang="en-US">Feldsphatic-ceramic CAD-CAM bars were cut into blocks (12×10×4 mm) with a cutting machine (N = 32). </span><span lang="en-US">Impressions were made of each ceramic block with silicone putty material and the negative space was filled with a composite resin.</span><span lang="en-US"> The bonding ceramic surface was etched with hydrofluoric acid, silanized, and the adhesive system (SB- Single Bond 2, 3M-ESPE; or PB- Prime &amp; Bond NT, Dentsply) was applied. The samples were dried at different times (5, 10 and 15 s) before the cementation. The resin and ceramic blocks were cemented by a dual cure resin cement. All samples were stored in distilled water at 37 °C for 24 h. For the μ-TBS test, the samples were sliced into microbars. Half of the bars of each block was tested after 24 h and, the other bars </span><span lang="en-US">were submitted to thermocycling (12,000×) and water storage (150 d)</span><span lang="en-US">. For the 24 h groups, the longer drying time increased (p &lt; 0.05) the bond strength of SB (water/alcohol adhesive), while reduced (p &lt; 0.05) for the PB group (acetone based adhesive). </span><span lang="en-US"><strong>Results: </strong></span><span lang="en-US">For the aged groups, the bond strength for the different drying times had no significant difference, for the both adhesives. </span><span lang="en-US"><strong>Conclusion:</strong></span><span lang="en-US"> Longer drying times increased the bond strength values of SB. Smaller drying times increased the bond strength values of PB. The aging protocol influenced the bond strength of SB groups.</span></p><p class="western"> </p><p class="western" lang="pt-BR"><span><span><span lang="en-US"><strong>Keywords:</strong></span></span></span><span><span><span lang="en-US"><span> Microtensile; Adhesion; Feldspar ceramic; Drying time; Adhesive system.</span></span></span></span></p>

scholarly journals Impact of Endodontic Instrumentation on Surface Roughness of Various Nickel-Titanium Rotary Files

2020 ◽  
Author(s):  
Muhammad Sohail Zafar
Keyword(s):  
Surface Roughness ◽  
Three Dimensional ◽  
Nickel Titanium ◽  
Root Mean Square Roughness ◽  
Contact Mode ◽  
Root Canals ◽  
Working Length ◽  
Mandibular Molar ◽  
Significant Difference ◽  
Before And After

Abstract Objectives The aim of the present study was to evaluate the surface roughness (SR) of various nickel-titanium (NiTi) rotary endodontic instruments (ProTaper Next [PTN], WaveOne Gold [WOG], and ProTaper Gold [PTG]) before and after root canal instrumentation. Materials and Methods For each type (PTN, WOG, and PTG), the endodontic instrumentation was performed using extracted mandibular molar teeth’s curved mesial root canals (curvature: 20–40 degrees) after determining the working length. Each NiTi file was cleaned, and sterilized following preparation of four root canals and characterized for surface properties before and after endodontic instrumentation using a contact-mode three-dimensional surface profiler. The data were analyzed statistically using Statistical Package for the Social Sciences for SR parameters including average surface roughness value (Sa), root mean square roughness (Sq), and peak to valley height (Sz). Results Preinstrumentation assessment revealed a significant difference for all the three SR variables (p < 0.05) for the cutting blade and the flute area. WOG instruments showed the highest SR values (p = 0.000). The postinstrumentation assessment revealed significant differences in SR values in the blade and the flute between the three groups (p < 0.05), with WOG and PTG exhibiting the highest values in the blade and flute sections, respectively. Conclusions The SR parameters of intact PTN, WOG, and PTG NiTi files vary and that was increased following the endodontic instrumentation.

scholarly journals Nanoleakage for Self-Adhesive Resin Cements used in Bonding CAD/CAD Ceramic Material to Dentin

2011 ◽  
Vol 05 (03) ◽  
pp. 281-290 ◽  
Author(s):  
Wafa El-Badrawy ◽  
Randa Mohamed Hafez ◽  
Abeer Ibrahim Abo El Naga ◽  
Doaa Ragai Ahmed
Keyword(s):  
Nitrate Solution ◽  
Silver Nitrate Solution ◽  
Resin Cement ◽  
Resin Cements ◽  
Adhesive Resin ◽  
Nail Polish ◽  
Significant Difference ◽  
Cad Cam ◽  
Ceramic Blocks ◽  
Post Hoc

ABSTRACTObjectives: To determine nanoleakage of CAD/CAM ceramic blocks bonded to dentin with selfadhesive resin cement. Methods: Eighteen sound extracted human molars were sterilized and sectioned into 3 mm-thick dentin sections. Trilux Cerec Vitablocks (Vita) were also sectioned into 3 mm sections, surfacetreated using 5% hydrofluoric acid-etchant, and then coated with silane primer (Vita). Trilux and dentin sections were cemented together by means of three resin cements: Rely-X Unicem (3M/ ESPE), BisCem (Bisco), and Calibra (Dentsply), according to manufacturers' recommendations. Calibra was used in conjunction with Prime/Bond-NT adhesive (Dentsply), while the other two are self-adhesive. The bonded specimens were stored for 24h in distilled water at 37°C. Specimens were vertically sectioned into 1 mm- thick slabs, yielding up to six per specimen. Two central slabs were randomly chosen from each specimen making up the cement groups (n=12). Each group was subdivided into two subgroups (n=6), a control and a thermocycled subgroup (5-55°C) for 500 cycles. Slabs were coated with nail polish up to 1 mm from the interface, immersed in a 50% silver nitrate solution for 24h, and tested for nanoleakage using Quanta Environmental SEM and EDAX. Data were statistically analyzed using two-way ANOVA and Tukey's post-hoc tests. Results: Rely-X Unicem and Calibra groups demonstrated no significant difference in the percentage of silver penetration, while the BisCem group revealed a significantly higher percentage (P≤.05). Thermocycling (500 cycles) did not have a statistically significant effect on the percentage of silver penetration (P>.05). Conclusions: One self-adhesive-resin cement demonstrated a similar sealing ability when compared with a standard resin cement. Thermo-cycling did not significantly increase dye penetration under the test conditions. (Eur J Dent 2011;5:281-290)

The Accuracy of Optical Scanning: Influence of Convergence and Die Preparation

2011 ◽  
Vol 36 (5) ◽  
pp. 486-491 ◽  
Author(s):  
DCN Chan ◽  
AK-H Chung ◽  
J Haines ◽  
EH-T Yau ◽  
C-C Kuo
Keyword(s):  
Surface Area ◽  
White Light ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
Area Measurement ◽  
Finish Line ◽  
Optical Scanner ◽  
Significant Difference ◽  
Computer Aided ◽  
Cad Cam

SUMMARY The purpose of this study was to determine the reliability of the data acquisition and modeling process of laser and white light scanners by evaluating the reproducibility of digitized simulated crowns with different convergences. A secondary purpose was to analyze the influence of die preparation by testing this hypothesis with a set of dies without ditching compared with a set with well-defined margins. Ditching or trimming the die defines the position of the margin and acts as a guide to gingival contour when the restoration is being waxed. Two light scanners (a white light optical scanner [Steinbichler Gmbh, Neubeuern, Germany] and red laser light scanner [TurboDent System, Taichung, Taiwan]) were evaluated. Two sets of simulated crowns were fabricated as cone frustrum models with a total occlusal convergence (TOC) of 0°, 5°, 10°, 15°, 20°, and 25° and a 9-mm base and 3-mm height using a precision milling machine and computer-aided design/computer-aided manufacturing (CAD/CAM) technique. One set of the dies was ditched immediately below the finish line to enhance marginal definition. Each die was optically digitized five times directly with the two different measuring systems. The area of each triangle in the scan that is occlusal to the margin line was calculated and summed to produce the final surface area measurement provided. The digitizing error was compared with the computed surface area of the original master die sets and compared with a paired t-test (df=4; 95% CI). There was no difference in accuracy of the untrimmed dies between the two systems evaluated. We also did not find any difference in the 0° (p=0.12) and 5° degree (p=0.21) groups among the ditched dies. However, when the TOC exceeded 5°, there was a significant difference between the two groups, with the laser groups having a smaller error percentage. Three-dimensional light scanning was not affected by the convergence angle except in the 0°-5° range. Trimming the dies greatly affected the accuracy of scanning.

scholarly journals The comparison of the rate of apical displacement in curved root canals using Neoniti and RaCe files by cone beam CT Scan

2019 ◽  
Vol 22 (3) ◽  
pp. 313-320
Author(s):  
Mostafa Godiny ◽  
Nafiseh Nikkerdar ◽  
Reza Hatam ◽  
Leila Shahsavand ◽  
Atefeh Khavid
Keyword(s):  
Root Canal ◽  
Cone Beam Ct ◽  
File Systems ◽  
Root Canals ◽  
Mandibular Molar ◽  
Significant Difference ◽  
Before And After ◽  
Molar Teeth ◽  
Canal Transportation ◽  
The Mean

Background and aim: There is a high prevalence of root canal transportation in the teeth with the curve. effect of root canal transportation on the success of root canal therapy of tooth is negative and there is no study about comparing RaCe and Neoniti files in root canal transportation. The aim of this study is assessment and comparing two different RaCe and Neoniti files to determine transportation error in various parts of root using CBCT assessment and comparing them with each other.Method: In this experimental study 50 extracted mandibular molar teeth selected. Teeth were divided randomly into two groups i.e. 25 teeth threated with RaCe file (first group) and 25 teeth threated with Neonitu files (second group). in this study to measurement  thickness of dentine in the scan ,before and after instrumentation at the same time we used axial images that obtain from NNT viewer 6.1.0 software .Findings: in the first group ,The mean tooth transportation  in 5 mm of apex  was 0.15 and  in the second group The mean tooth transportation  in 5 mm of apex  was 0.18 mm that there was no statistically significant difference in canal transportation  between RaCe and Neoniti files in five millimeters distant from apex area (p=0.492) and the mean transportation from 9 mm of apex was 0.14 in the second group that There was no statistically significant difference in canal transportation between two  groups (p=0.911).Conclusion: The results indicated that there was no significant difference of tooth transportation between two file systems in 3, 9, 7, 5 and 11mm from the apex and both files were safe.  

scholarly journals The Internal and Marginal Adaptation of Zirconia Based Fixed Dental Prostheses in the Posterior Region

2021 ◽  
Author(s):  
Ayşe Koçak-Büyükdere ◽  
Atilla Sertgöz
Keyword(s):  
Cross Sections ◽  
Clinical Success ◽  
Optical Microscope ◽  
Marginal Adaptation ◽  
Dental Prostheses ◽  
Occlusal Surfaces ◽  
Cad Cam ◽  
Molar Teeth ◽  
Fixed Dental Prostheses ◽  
Internal Fit

Purpose:Long-term clinical success is closely related to the internal and marginal adaptation of the restorations. Thepurpose of this study was to evaluate the internal adaptation of zirconia-based fixed dental prostheses in the posteriorregion.Materials & Methods:Four-unit porcelain-fused to zirconia fixed dental prostheses were fabricated with CAD-CAMsystem in 20 patients. For the evaluation of the restorations’ internal fit, conventional silicone replicas were used withthe optical microscope. The obtained silicone impression was cut to obtain two cross-sections from buccolingual and 3from mesiodistal. Fifty different measurements were taken from every tooth by taking 10 from each cross- section; 2from the margin, 6 from the axial surfaces and 2 from the occlusal by the optical microscope.Results:There were statistically significant differences in internal discrepancy in terms of area and tooth type. Theaverage internal discrepancy on the axial surfaces of the molars was 142.39±47.42μm. In premolars, the mean was139.53±46.80μm. The average of the internal discrepancy values obtained from occlusal surfaces of the molar teeth was164.39±53.61μm, whereas the same average for the premolar teeth was 161.92±60.54μm.Conclusion:Within the limitations of this study, restorations fabricated by CAD/CAM and internal and marginaldiscrepancies were at clinically acceptable intervals

scholarly journals Evaluating the masking ability of CAD/CAM hybrid ceramics with different thicknesses

2021 ◽  
Vol 11 (2) ◽  
pp. 114-120
Author(s):  
Beyza Ünalan Değirmenci ◽  
Farhad Wahid RASOOL
Keyword(s):  
English Language ◽  
Native Speakers ◽  
Resin Cement ◽  
Significant Difference ◽  
Color Differences ◽  
Cad Cam ◽  
Ceramic Blocks ◽  
Native Speakers Of English ◽  
Nanohybrid Composite ◽  
Hybrid Ceramic

Aim:  A discoloration existing under the restoration can affect the final restoration color, and various techniques can be used to address this situation. The aim of this study was to investigate the masking ability of the substructure, color of different hybrid CAD/CAM ceramics in various thicknesses. Methodology: A total of 120 samples were produced from 4 different CAD/CAM hybrid ceramic blocks (Cerec blocs, GC Cerasmart, Vita Enamic, 3M Lava Ultimate) in 1, 1.5 and 2 mm thickness. The samples were sliced with 100 N pressure in a low-speed precision cutting device under water cooling. The specimens were placed over the neutral grey background for initial spectrophotometric measurements. A3 color posterior nanohybrid composite (14 X 7 X 1 mm) was preferred to mimic discoloration in the substructure. The cementation procedure of composite and the CAD/CAM hybrid ceramic complex was standardized under 10 N continuous pressure and was performed using a dual cured resin cement. All samples were incubated at 37 °C for 24 hours in incubator after cementation. And the second spectrophotometeric measurement was done via the L*, a*, and b* color attributes of the complex specimens. Additionally, ΔE* values were calculated to determine the color differences between each group. Kruskal Wallis test was used for statistical analysis and Dunn’s test was used for group comparison. Significance was evaluated at least p <0.05. Results: It was found that thickness of the ceramics increases, the substructure color is better masked and the thickness made a statistically significant difference on the masking ability (p<0.01). For 1 mm thick samples, the highest ΔE* value was found in Cerec blocs with 9.36, while the lowest value was found in GC Cerasmart as 4.27. Conclusion: Within the limitations of this study, it was concluded that the tested CAD/CAM hybrid ceramics showed better masking ability than Cerec blocs.   How to cite this article: Ünalan Değirmenci B, Wahid WF. Evaluating the masking ability of CAD/CAM hybrid ceramics with different thicknesses. Int Dent Res 2021;11(2):114-20. https://doi.org/10.5577/intdentres.2021.vol11.no1.9   Linguistic Revision: The English language in this manuscript has been checked by at least two professional editors, both native speakers of English.

scholarly journals A Comparative In Vitro Study Evaluating the Marginal Adaptation of Zirconium Computer-Aided Design/Computer-Aided Manufacture and Press-ceramic Veneers

Folia Medica ◽  
2020 ◽  
Vol 62 (3) ◽  
pp. 546-552
Author(s):  
Aleksandra Pecheva ◽  
Kostadin Georgiev ◽  
Snezhana Tsanova ◽  
Ralitsa Raycheva
Keyword(s):  
Computer Aided Design ◽  
Clinical Success ◽  
Marginal Adaptation ◽  
Marginal Gap ◽  
Mean Values ◽  
Significant Difference ◽  
Computer Aided ◽  
Cad Cam ◽  
Internal Adaptation ◽  
The Mean

Introduction: One method to evaluate the clinical success of cemented restorations is measuring the marginal adaptation. There is a correlation between the fitting of the restoration and problems caused by clinically undetectable passage of bacteria between the tooth structure and the veneer. Aim: To evaluate in comparison the marginal adaptation of veneers produced via CAD/CAM and press technique. Materials and methods: 32 extracted incisors are divided into two equal-number groups (n=16) according to the production technique &ndash; CAD/CAM zirconium veneers and press-ceramic veneers. Cut sections are examined under a SEM magnification. Marginal accuracy is measured as the distance between the finish line of the tooth and the margin of the veneer at eight fixed locations. Results: The mean values of marginal gap of group 1 are: external adaptation &ndash; 79.88&plusmn;3.71 &micro;m; internal adaptation &ndash; 79.14&plusmn;15.70 &micro;m; cervical adaptation &ndash; 82.39&plusmn;28.55 &micro;m; incisal adaptation &ndash; 86.85&plusmn;21.72 &micro;m. The mean values of marginal gap of group 2 are: external adaptation &ndash; 100.31&plusmn;2.16 &micro;m; for internal adaptation &ndash; 101.01&plusmn;12.51 &micro;m; cervical adaptation &ndash; 91.55&plusmn;3.31 &micro;m; incisal adaptation &ndash; 93.76&plusmn;2.54 &micro;m. Conclusions: Veneers produced via CAD/CAM technology have better fit at the external and internal marginal wall. There is no statistically significant difference between the gaps at the cervical and the incisal areas.

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