scholarly journals Laboratory Characterization of In-Service Full-Mouth Rehabilitation with Monolithic Translucent Zirconia Restorations

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1755
Author(s):  
Susana M. Salazar Marocho ◽  
Mary Beth VanLandingham ◽  
Firas Mourad ◽  
Andres Pappa ◽  
Sreenivas Koka
Keyword(s):  
Surface Roughness ◽  
Surface Damage ◽  
Optical Microscope ◽  
Posterior Teeth ◽  
Golden Proportion ◽  
Laboratory Characterization ◽  
Full Mouth Rehabilitation ◽  
Zirconia Crowns

The chance to critically and microscopically inspect the quality of bonded restorations once they are delivered to the patient after several pre-cementation steps is rare or nonexistent. Replicas of in-service restorations can provide a wealth of information on the integrity of the restorations and moreover make it possible to bring this information to the laboratory for further detailed analysis. This study aimed to characterize the epoxy replicas of 27 cemented monolithic yttria-stabilized zirconia crowns of the maxillary and mandibular arch to assess surface roughness, topography, and symmetry. The topography of the facial, lingual, and occlusal/incisal surfaces of each crown was observed under the optical microscope and further characterized using the scanning electron microscope. Surface roughness measurements were performed using the atomic force microscope. The optical microscope was used to measure the golden proportion and visible width of the anterior maxillary crowns. Surface damage consistent with unpolished adjustment was identified mostly in the occlusal surface of the posterior teeth. Other irregularities, such as scratch marks, small pits, and coarse pits were also found. The surface roughness had great variability. Not all of the anterior maxillary and mandibular teeth followed the golden proportion concept. This study design allows in vitro characterization of in-service restorations. It provides a framework for using replicas for early identification of patterns or features that can trigger fracture and for analysis of morphology and symmetry.

Tubing String Thread Sealing Surfaces Damage Evaluation Based on Acoustic Elasticity Theory

2019 ◽  
Vol 944 ◽  
pp. 828-834 ◽  
Author(s):  
Jian Jun Wang ◽  
Jian Hua Sun ◽  
Shang Yu Yang ◽  
Yao Rong Feng ◽  
Kai Lin
Keyword(s):  
Surface Roughness ◽  
Elasticity Theory ◽  
Contact Stress ◽  
Surface Characterization ◽  
Surface Damage ◽  
Center Frequency ◽  
Sealing Performance ◽  
Tubing String ◽  
Acoustic Elasticity

During the processing of tubing premium threaded made up, the degree of the thread sealing surface intactness will directly affect the sealing performance of the string. Nevertheless, there are some difficulties to detect the damage of the engaged sealing surface effectively. In the present study the sealing surface damage was judged by the sealing surface contact stress’s relative changes according to the acoustic elasticity theory,. At the same time, the wear defects generated at the tubing sealing surface, during the tubing made up, contrasted with the wear and unworn surface roughness of coupling ultrasonic detected about the sealing surface. The results showed that with the acoustic amplitude evaluated the sealing contact stress was susceptible to the influence of surface roughness of coupling. But the reflection wave with the center frequency on the sealing surface characterization of the contact stress could avoid this problem effectively.

Assessment of Quantitative Methodology for Evaluation of Retrieved Metallic Femoral Components From Total Knee Replacements

2011 ◽  
Author(s):  
Estefania Alvarez ◽  
Marcella E. Elpers ◽  
Hillary M. Cash ◽  
Michelle E. Wabler ◽  
John D. DesJardins
Keyword(s):  
Surface Roughness ◽  
Femoral Component ◽  
Joint Replacement ◽  
Total Joint Replacement ◽  
Articular Surface ◽  
Surface Profile ◽  
Surface Damage ◽  
Damage Score ◽  
Visual Damage

The metallic surfaces of total joint replacement components are subject to surface damage and roughening that can severely limit the service lifetime of the bearing system. To date, there are no standards by which to characterize the severity and modes of this critical surface damage, and therefore it remains difficult to accurately assess how femoral damage influences total joint replacement longevity. This study introduces a novel femoral component damage scoring methodology that combines a semi-quantitative visual damage scoring assessment and a fully quantitative non-contact characterization of the articular surface profile. The femoral surface was divided into 6 pre-determined zones, with 5 possible modes of damage and 4 (0–3) levels of damage severity, to produce a maximum possible damage score of 90. The 5 modes of metallic surface damage were; number of scratches, scratch depth, third body wear, abrasion and pitting. Three independent examiners were trained and then evaluated 33 retrieved TKRs systems (n = 11 Oxinium and n = 23 CoCr) with in-situ times of 3.6 ± 4.2 yrs (range of 0.1–20 yrs). The average damage score was 19.9 ± 30.8 with an inter-observer variability of only 1.5% Articular damage mode frequency was calculated and found to be 61% for scratching, 15% for pitting and 52% for abrasion. The quantitative characterization of the articular surface profile of the femoral component using non-contact profilometry (n = 150/retrieved component) illustrated a positive correlation between damage score and the average surface roughness for implants with an Ra greater than 65 nm (R2 of 0.865). This methodology identified a critical Ra threshold above the standard manufacturing tolerance (∼50nm) wherein visual damage scoring was predictive of increases in quantitative surface roughness. This study validates the use of this novel methodology across most TKR material pairings. Future work will correlate damage scores and measured surface roughness with patient demographic and functional information.

scholarly journals Molar Buccal Tubes Front and Back Openings Dimensions and Torsional Play

2018 ◽  
Vol 30 (3) ◽  
pp. 32-39
Author(s):  
Hiyam J Al-Zubaidi ◽  
Akram F Alhuwaizi
Keyword(s):  
Orthodontic Treatment ◽  
In Vitro Study ◽  
Free Fall ◽  
Optical Microscope ◽  
The Other ◽  
Posterior Teeth ◽  
Adobe Photoshop ◽  
The Wire ◽  
Metal Block

Background/: Buccal tubes are orthodontic attachments used on the posterior teeth instead of bands, so it is important to focus on the effect of their properties on orthodontic treatment. The aims of the present in vitro study are to evaluate and compare the buccal tube front and back openings dimensions and the torsional play angle of six different brands. Materials and Methods: The samples consisted of Single bondable, non-convertible first molar buccal tubes from six brands supplied from six companies (Dentaurum, Forestadent, Ormco, 3M, American Orthodontic, A-Star). Regarding tube opening dimension, ten buccal tubes of each brand were examined by an optical microscope. Each tube was fixed during examination using synthetic mud and oriented for observation of the front and back slot openings. A picture was taken for both tube openings and the result appeared on the computer's screen where width and height measurements were made. While regarding torsional play angle, ten buccal tubes of each brand were used. Each tube was fixed on a metal block attached to a surveyor base. Then an L-shaped wire was inserted inside the front opening of the tube. Two photographs were taken, one with the wire in free fall position and the other with the wire elevated by a 10g weight with the same angle of shooting as the first photograph. Later, the two images were superimposed in Adobe Photoshop program, and an electronic MB-ruler Software was used to calculate the angle which represents the torsional play within each tube. The data were then statistically analyzed using ANOVA and LSD tests. Results: There are marked differences between measured tube dimensions and the manufacturer stated dimensions with the front tube openings being generally larger than the back opening dimensions. Furthermore, the torsional play angle was highest in A-Star and smallest in Ormco's tubes. This angle was significantly correlated to the height of the tube front opening. Conclusion: It can be concluded that tube dimension varies among different companies and effect greatly torsional play angle.

Effects of Deposition Temperature on the Growth Characteristics of CVD SiC Coatings

2008 ◽  
Vol 368-372 ◽  
pp. 846-848 ◽  
Author(s):  
Yan Li Huo ◽  
Yu Feng Chen
Keyword(s):  
Surface Roughness ◽  
Grain Size ◽  
Phase Composition ◽  
Crystallite Size ◽  
Deposition Temperature ◽  
Optical Microscope ◽  
Columnar Structure ◽  
Growth Characteristics ◽  
Sic Coatings

The effects of deposition temperature on the growth characteristics of CVD SiC coatings were investigated. CVD SiC coatings were made by pyrolysis of methyltrichlorosilane (MTS) in hydrogen at a low pressure of 5kPa. The ratio of MTS to hydrogen was 1/12. The deposition temperatures were varied from 1373K to 1503K. Optical microscope and SEM were used to observe the surface morphology and microstructure of the coatings. XRD was used for characterization of the phase composition. Results indicated that the deposition rate and the surface roughness varied with deposition temperature. At 1373K, the deposited grains were mainly equiaxed with the crystallite size of 22 nm. However, when the deposition temperature was 1503K, the SiC grains were mainly showed faceted columnar structure with the crystallite size of 32 nm. Grain size increased with the increase of deposition temperature.

Inappropriate Toothbrushes Selection Alter Composite Dental Material Restoration Surface Roughness: A Preliminary Study

2016 ◽  
Vol 696 ◽  
pp. 108-112
Author(s):  
Elylla Oktaviana ◽  
Retno Ardhani ◽  
Heribertus Dedy Kusuma Yulianto
Keyword(s):  
Surface Roughness ◽  
Dental Plaque ◽  
Resin Composite ◽  
In Vitro Study ◽  
Surface Damage ◽  
Dental Material ◽  
Secondary Caries ◽  
Group A ◽  
Preliminary Study

Introduction. Regular dental plaque control by means of chemically and mechanically methods are among efforts to improve oral health and hygiene. Mechanical cleansing using toothbrush is still the gold standard for continually removing of dental plaque. But on the other hand, inappropriate selection of toothbrushes type selection promotes alteration on dental material restoration surface. Toothbrushes with different degree of stiffness are readily available on market and are classified as hard, medium, and soft. Mechanical friction due to regular movement of the toothbrush with various degree of stiffness was predicted as factor that related with surface roughness alteration on dental material restoration. Nowadays, resin composite material is still declared as the material of choice to repair dental hard tissue damage due to caries activity. However, it has been found that the irregularity of surface promotes bacterial adhesion and biofilm deposition, whereas the smooth surface does not favor bacterial deposition. The progress of bacterial deposition promotes secondary caries on the margin between material restoration and teeth. The aim of this in vitro study was to evaluate the influence of brushing treatment by means of three different toothbrushes on the surface of resin-based compositesExperimental. Specimens were prepared from experimental RBCs with 5 mm diameter and 2 mm thick. Specimens were divided equally into 3 different groups (group A, B, and C). Each group has 5 numbers of specimens. Group A was treated with hard toothbrush, and group B as well as C were treated with medium and soft toothbrush respectively. The toothbrush was mounted in the customized mechanically brushing machine to control the force and number of cycle during specified time. Brushing cycle and time for all groups was conducted for 1000 times of brushing in 60 minutes. Surface roughness resulted from mechanically brushing is evaluated by means of profilometer device.Results and Discussion. The results of the preliminary study shows that there is a differences of surface roughness between groups. The value of roughness varied among all group, and the highest number of roughness were found in group A (> 0.2 micrometres).Conclusions. This result implies brushing with hard toothbrush preferentially has greater risk of surface damage and become pronounce factor of secondary caries.

scholarly journals Surface, Microstructural, and Mechanical Characterization of Prefabricated Pediatric Zirconia Crowns

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3280 ◽  
Author(s):  
Valeria Diener ◽  
Georgrios Polychronis ◽  
Juliane Erb ◽  
Spiros Zinelis ◽  
Theodore Eliades
Keyword(s):  
Surface Roughness ◽  
Clinical Performance ◽  
Indentation Modulus ◽  
Roughness Parameters ◽  
Raman Analysis ◽  
Surface Roughness Parameters ◽  
Multiple Comparison Test ◽  
Zirconia Crowns ◽  
One Way Anova

The purpose of this study was to characterize the surface roughness, the microstructure, and mechanical properties of four prefabricated zirconia pediatric crowns. Ten prefabricated crowns from four different manufacturers (Cheng Crowns Zirconia), (EZCrowns), (NuSmile ZR), and (Zirconia Pediatric Crowns) were included in this study. The surface roughness parameters (Sa, Sq, Sz, Sc, and Sv) of all samples were studied by optical profilometry and then the microstructure was studied by Raman spectroscopy. Then, all samples were embedded in epoxy resin and after metallographic polishing, the Martens hardness (HM), indentation modulus (EIT), elastic index (ηIT), Vickers hardness (HV), and fracture toughness (KIC) were identified by the Instrumented Indentation Testing (IIT). All data were statistically analyzed by a one-way ANOVA and a Tukey multiple comparison test at α = 0.05. Only the tetragonal phase of zirconia for all materials tested was identified after Raman analysis. However, statistically significant differences were found among the surface roughness parameters, HV and KIC, while no differences were allocated for HΜ, EIT, and ηΙΤ. Although the materials tested shared a similar microstructure, significant differences in surface roughness parameters HV and KIC were identified and, thus, differences in their clinical performance were anticipated.

Evaluation of Surface Properties and In Vitro Characterization of Surface Modified In Situ TiO2 Nanofibers

2015 ◽  
Vol 656-657 ◽  
pp. 63-67
Author(s):  
Ai Wen Tan ◽  
Belinda Pingguan-Murphy ◽  
Roslina Ahmad ◽  
Sheikh Akbar
Keyword(s):  
Surface Roughness ◽  
Articular Chondrocytes ◽  
Degree Of Crystallinity ◽  
X Ray ◽  
Atomic Force ◽  
Bovine Articular Chondrocytes ◽  
Surface Modified

In situ TiO2 nanofiber arrays have been successfully produced directly on a Ti-6Al-4V substrate by using thermal oxidation under a limited supply of oxygen. Their morphology, elemental composition, crystal structure, surface roughness and surface wettability were characterized by field-emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffractometer (XRD), atomic force microscope (AFM) and contact angle goniometer, respectively. The results of material characterization studies revealed that TiO2 nanofibers possessed greater surface roughness and wettability, as well as the degree of crystallinity. In vitro characterization have also been evaluated by using bovine articular chondrocytes on the resulting TiO2 nanofibrous surface at different time points. Cell adhesion was observed qualitatively by using FESEM and cell proliferation was determined quantitatively by using AlamarBlue reduction assay. The results showed that the TiO2 nanofibrous substrate triggers enhanced chondrocytes adhesion, proliferation, and production of extracellular matrix (ECM) fibrils compared to untreated substrate. These results suggest that the oxidation process produces a surface structure to which chondrocytes affinity, and thus this surface would has potential use in implants designed for cartilaginous applications.

scholarly journals New Formulation and Characterization of Topical Films of Tioconazole and Evaluation of Their Antifungal Therapy

2021 ◽  
pp. 400-408
Author(s):  
Siddique Akber Ansari
Keyword(s):  
Room Temperature ◽  
Mechanical Characterization ◽  
Inhibition Zone ◽  
Optical Microscope ◽  
Glycerol Solution ◽  
The Novel ◽  
Swelling Studies ◽  
New Formulation

Purpose: New formulation of Scleroglucan (Sclg) films loaded with tioconazole, a medication typically applied for dermal treatments prepared. The feasibility of that treatment relies on                      the penetration of medications through the target layers of the skin in effective                 concentrations. Methods: Dynamic and mechanical characterization and swelling studies of the novel delivery system were analysed. An aqueous solution of Sclg (Cp=1% w/v) and glycerol (2% w/v) was prepared and kept at room temperature under magnetic stirring for 72 hrs. Tioconazole previously solubilised in Labrasol, was added to the polymer/glycerol solution.  4 ml of solution was poured in a plastic plate. The films were dried at 40°C for 1 hr and then allowed to dry at room temperature (about 25°C) for a week. Translucent films were obtained. The fungal strain used to test the film are CO23 sensitive to drugs, CO23 RFLC resistant to fluconazole, CO23 RFK resistant to  micafungin, ATCC  standard strain. Results: The water uptake of the films significantly increased up to 24 hrs. The optical microscope films images show that the presence of the drug did not significantly influence the appearance of the samples. The in vitro studies demonstrated the perceptible fungal activity of the new formulation against Candida albicans infections. Conclusion: The patches showed antimicrobial activity against all tested strains. An evident inhibition zone diameter, about 40 mm, for the strains sensitive to azoles (CO23 RFK and CO23) in comparison to strain resistant to fluconazole (CO23 RFLC) was observed. After 48 hours the inhibition zone diameters were reduced of about 6-7 mm in comparison to those observed after 24 hours of incubation.

scholarly journals Comparison of surface roughness of nanofill and nanohybrid composite resin polished by aluminum oxide and diamond particle paste

2017 ◽  
Vol 29 (2) ◽  
Author(s):  
Yolanda Y. ◽  
Dudi Aripin ◽  
Opik Taofik Hidayat
Keyword(s):  
Surface Roughness ◽  
Aluminum Oxide ◽  
Resin Composite ◽  
Diamond Particle ◽  
In Vitro Study ◽  
Optical Microscope ◽  
Composite Surface ◽  
Color Retention ◽  
Nanohybrid Composite

Introduction: The adequate finishing and polishing procedures might occur the restoration longivity, the color retention, and the good integrating with the surrounding environment. Methods: This study was conducted to determine the surface roughness of the nanofill composite with the nanohybrid composite polished by the aluminum oxide pastes and diamond polishing paste. This study was a pure experimental-in vitro study. The results of polishing on the resin composite surfaces was observed using the optical microscope at 500x magnification and given the score. The Krusskal-Wallis test was conducted to depict the data analysis. Result: The results showed that the resin composite group of the nanohybrid polished by both aluminum oxide and diamond particle had smoother surface than the resin composite of the nanofill. Conclusion: The conclusions of this study depicted that there were differences of polishing results using the aluminium oxide and diamond particle paste between the nanofill and nanohybrid resin composite surface roughness.

scholarly journals Comparative retrieval analysis of antioxidant polyethylene: bonding of vitamin-E does not reduce in-vivo surface damage

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Dominic T. Mathis ◽  
Joshua Schmidli ◽  
Michael T. Hirschmann ◽  
Felix Amsler ◽  
Johann Henckel ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Titanium Alloy ◽  
Vitamin E ◽  
Surface Damage ◽  
Antioxidant Vitamin ◽  
Tibial Tray ◽  
Positive Effects ◽  
Retrieval Analysis

Abstract Background With the Persona® knee system a new polyethylene formulation incorporating vitamin-E which aims to reduce oxidation and maintain wear resistance was introduced. Although in-vitro studies have demonstrated positive effects of the vitamin-E antioxidants on UHMWPE, no retrieval study has looked at polyethylene damage of this system yet. It was the aim to investigate the in-vivo performance of this new design, by comparing it with its predecessor in retrieval analysis. Methods 15 NexGen® and 8 Persona® fixed-bearing implants from the same manufacturer (Zimmer Biomet) were retrieved from two knee revision centres. For retrieval analysis, a macroscopic analysis of polyethylene using a peer-reviewed damage grading method was used (Hood-score). The roughness of all articulating metal components was measured using a contact profilometer. The reason(s) for TKA revision were recorded. Statistical analyses (t-test) were performed to investigate differences between the two designs. Results The mean Hood score for Persona® inserts was 109.3 and for NexGen® 115.1 without significant differences between the two designs. Results from the profilometer revealed that Persona® and NexGen® femoral implants showed an identical mean surface roughness of 0.14 μm. The Persona® tibial tray showed a significantly smoother surface (0.06 μm) compared to the NexGen® (0.2 μm; p < 0.001). Both Hood score and surface roughness were influenced by the reasons for revision (p < 0.01). Conclusions The bonding of the antioxidant vitamin-E to the PE chain used in the novel Persona® knee system does not reduce in-vivo surface damage compared to highly crosslinked PE without supplemented vitamin-E used in its predecessor knee system NexGen®. However, the Persona® titanium alloy tibial tray showed a significantly smoother surface in comparison to the NexGen® titanium alloy tibial tray. This study provides first retrieval findings of a novel TKA design and may help to understand how the new Persona® anatomic knee system performs in vivo.

Sign in / Sign up

Export Citation Format

Share Document