Wyniki wyszukiwania - BazTech

1

Assessment of marginal integrity of five different polymers in retrograde root-end filling following apicoectomy: An in-vitro analysis with scanning electron microscope and micro-radiography

Gülses Aydin, Ayna Mustafa, Emmert Marie, Karataban Piran, Kübel Paul, Wiltfang Jörg, Acil Yahya

Acta of Bioengineering and Biomechanics

|

2021

|

Vol. 23, no. 3

133--145

EN

Purpose: The aim of the study was to evaluate marginal adaptation properties of five different sealers used as root filling material. Materials: Apical resection was performed on 100 canals of 50 maxillary premolars in slaughtered pigs. The root end of 24 canals were retrogradely filled with Diaket™, 37 root canals with Super-EBA™ including 18 with Super-EBA™. Regular and 19 with Super-EBA™ fast, 20 canals with ProRoot® MTA and 19 canals with AH-Plus™. For quantitative examination, scanning electron microscope (SEM) analysis and for qualitative examination, microradiography was performed. Results: Diaket™ achieved an overall average of 4.872 microns gap value as the best result. The mean values of marginal gap widths of AH-Plus™ and Super-EBA™ were almost with 8.044 microns and 9.951 microns in about the same magnitude, followed by Super-EBA™ Regular with 11,560 microns. Highest marginal gap value was found for ProRoot® MTA with 18.343 microns (p < 0.001). Conclusions: Both in terms of its marginal integrity and material properties, Diaket™ is the most suitable material for retrograde obturation. A preliminary version of the current paper could be found at www.researchsquare.com/article/rs-6198/v1.

2

Use of optical microscopy for evaluation of tooth structure

Banaszek K., Sawicki J., Wołowiec-Korecka E., Gorzędowski J., Danowska-Klonowska D., Sokołowski J.

Journal of Achievements in Materials and Manufacturing Engineering

|

2016

|

Vol. 79, nr 1

31--40

EN

Purpose: There are many methods of examining tooth anatomy: some of them are applicable to the hard tissues, while others to the pulp and the root canal system. Every method has some advantages and disadvantages in terms of revealing specific anatomical or histological details of the tooth. The objective of the present work was to assess the use of macroscopic microscopy for evaluation of tooth anatomy and to compare the obtained images with those produced by the radiovisiographic method. Design/methodology/approach: The study involved 4 upper canines extracted for periodontal reasons from patients of different age and sex. Initially, radiological images were taken in the vestibular-lingual and lateral projections by the radiovisiographic method using a KODAK 2000 system with a KODAK 6100 sensor. Subsequently, the specimens were ground with sandpaper and consecutive dental cross-sections were captured at approximately 0.05 mm increments using a NIKON AZ100 multizoom microscope. Findings: The presented method, using side illumination and a digital capture device transferring the images to a computer, enables evaluation of tooth anatomy in terms of both shape and internal structure, and offers the dimensioning functionality. Practical implications: Optical microscopy is a cheap method of examining the hard tissues of the tooth, including restorative materials, and for evaluating the development of primary and secondary dentin, as well as dentin affected by bacterial infection. A microscope used in conjunction with good software provides many opportunities for easy examination and dimensioning of particular anatomical features of the tooth on consecutive planes. Originality/value: This is an honest methods review and analysis which are applied in modern prosthetics.

3

Optyczna metoda rekonstrukcji geometrii zębów – Focus Variation

Burek J., Bazan A., Płodzień M, Turek P.

Pomiary Automatyka Kontrola

|

2013

|

R. 59, nr 10

1133--1135

PL

W artykule przedstawiono innowacyjną i niezależną optyczną metodę pomiaru geometrii Focus Variation, jako alternatywę dla aktualnie stosowanych rozwiązań wykorzystywanych w pomiarach biomodeli. Opisana metoda pomiarowa, umożliwia rekonstrukcję obiektów o niewielkich gabarytach i o skomplikowanej geometrii powierzchni. Dokonano analizy dokładności wykonania rekonstrukcji geometrii na przykładzie koron zębów. Uzyskane wyniki w ponad 80 procentach mieszczą się w granicach +-71 μm co świadczy o przydatności metody w zastosowaniach dentystyczno-stomatologicznych.

EN

This paper describes the principle of operation of the focus variation method used for optical 3D measurements. The goal of investigations was to analyse the quality of surface reconstruction of the tooth crown geometry and the usefulness of the method in the dental industry. The focus variation method combines the small depth of focus of an optical system with vertical scanning to provide topographical and colour information resulting from the variation of focus [5]. Fig. 2 shows the schematic diagram of a measuring system based on the focus variation method. It is possi-ble to measure surface points with high trueness using coordinate measuring machines (CMMs). However, limitation in the scanning speed as well as not accurate enough measurement of freeform surfaces such as fissure lines and interproximal areas make the access of the measuring probe to these places impossible. The measurement inaccuracy is due to the geometric size and shape of the tip of the stylus (probe) [3]. The results of the report (Fig. 5) are satisfactory for modeling so small and complex surfaces which are free crowns of the teeth. The focus variation method introduces new, more accurate scanning capabilities of the premises used in the dental industry.

4

Erosive potential of calcium-supplemented citric acid on bovine enamel

Stefański T., Malara P., Kloc-Ptaszna A., Postek-Stefańska L., Tyrpień-Golder K, Dobrzański L. A.

Archives of Materials Science and Engineering

|

2013

|

Vol. 64, nr 2

175--181

EN

Purpose: of this paper is to present results of wear resistance investigations of epoxy-hard coal composites produced by gravity casting Design/methodology/approach: In short introduction wear resistance of polymers is presented, methods used to prepare composites together with short characterization of physical properties of applied fillers are described. Wear resistance of the specimens was determined using Schopper-Schlobach method and APGi device. During the test, the rigidly fixed specimen moves with constant velocity along a rotating cylinder with abrasive paper type corundum P60 on its surface. Wear resistance of specimens was determined after 20 meters distance of abrasion under pressing load of10Nand expressed as the weight loss of the specimen after abrasion. Findings: Addition of the hard coal particles into the epoxy resin matrix caused a decrease of the wear resistance. Wear resistance decreased in a little extend with increasing filler content. Statistical analysis of achieved results showed that the influence of hard coal on wear resistance is significant comparing neat resin and filled resin but is not significant comparing composites with different solid particles content. Practical implications: Tested composite materials can be applied among others in electrical or chemical industry where electrical properties are important but wear resistance is not so important. Originality/value: New types of epoxy-hard coal graded composites were tested. It was demonstrated that by proper gravity casting technology control it is possible to produce graded composites for which hard coal particles do not deteriorate the wear resistance in significant extend.

5

Effect of water dilution and alcohol mixing on erosive potential of orange juice on bovine enamel

Malara L., Kloc-Ptaszna A., Dobrzański L., Górniak M., Stefański T.

Archives of Materials Science and Engineering

|

2013

|

Vol. 62, nr 1

15--21

EN

Purpose: This in vitro study aimed to evaluate the changes of erosive potential of an orange juice before and after mixing with water and alcohol. Design/methodology/approach: Fifty enamel specimens obtained from bovine teeth were prepared and randomly assigned into the following groups (n=10) with different erosive solution: I. commercially available pure orange juice (Cappy, Coca Cola Co.), II. orange juice diluted with distilled water at a ratio 3:1 (v/v), III. orange juice mixed with vodka (Smirnoff, 40% ethanol, Polmos) at a ratio 3:1 (v/v); IV. Orange juice diluted with distilled water (1:1, v/v), V. Orange juice mixed with vodka (1:1 v/v). The enamel specimens were submitted to a short-term erosion-remineralization cycling model (five 1-min erosion challenges in-between six 10-min remineralization periods in artificial saliva). Erosive potential of the drinks was assessed on the basis of chemical analysis and percent surface microhardness change (%SMHC) calculated from Vickers surface microhardness measurements before and after cycling. In chemical analysis of the experimental drinks, the pH value, titratable acidity, and buffer capacity (β) were determined. Findings: The pH of tested drink remained low even after dilution with water or mixing with alcohol, however, titratable acidity decreased after addition of water and alcohol. Short-term erosion-remineralization cycling resulted in significantly decreased surface microhardness of enamel specimens in all experimental groups. In the proportion of 3:1, juice mixed with alcohol resulted in significantly smaller %SMHC than juice diluted with water. This difference was not observed at a ratio 1:1. Practical implications: Consumers should be aware of tooth damage by drinks with low pH and high titratable acidity, even when mixing them with water and alcohol. Originality/value: To the best of our knowledge, this is the first study comparing the erosive effect of water-diluted orange juice with that of juice mixed with alcohol.

6

Określenie obciążenia ogniw łańcucha i flanki zęba bębna łańcuchowego przy kontakcie z torusem tylnym ogniwa

Dolipski M., Remiorz E., Sobota P., Osadnik J.

Wiadomości Górnicze

|

2011

|

R. 62, nr 10

550-559

PL

W artykule przedstawiono model obliczeniowy dla fragmentu obrotu bębna łańcuchowego od zetknięcia się tylnego torusa ogniwa poziomego z flanką zęba do zetknięcia się przedniego torusa następnego ogniwa poziomego z dnem gniazda, umożliwiający: wyznaczenie reakcji między torusem przednim ogniwa poziomego a dnem gniazda, siły w punkcie styku ogniwa poziomego z poprzedzającym ogniwem pionowym oraz reakcji między torusem tylnym ogniwa poziomego a flanką zęba w funkcji siły nabiegającej na bęben. Określono wartość siły tarcia zapobiegającej poślizgowi torusa tylnego ogniwa poziomego po flance zęba w stronę dna gniazda.

EN

The article presents a computational model for the fragment of rotation of the chain drum from the contact of a rear torus of a horizontal link with a flank of tooth till the contact of the front torus of the next link with the bottom of the seat, the power at the point of contact of the horizontal link with a proceeding vertical link and the reaction between the rear torus of horizontal link and the tooth's flank in a function of a winding power on the drum. The value of friction force preventing slippage of the rear torus of a horizontal link along the tooth's flank towards the bottom of a seat.

7

Jakość uprawy z zastosowaniem różnych maszyn do dwuwarstwowej uprawy gleby

Zbytek Z.

Problemy Inżynierii Rolniczej

|

2010

|

R. 18, nr 1

63-70

PL

Podstawową zasadą, stosowaną w rolnictwie ekologicznym, jest "głęboko spulchniać, płytko odwracać". Dotychczas do uprawy dwuwarstwowej stosowano pługi lemieszowe z pogłębiaczami. W Przemysłowym Instytucie Maszyn Rolniczych opracowano nowe rozwiązania konstrukcyjne maszyn (narzędzi) do dwuwarstwowej uprawy gleby. Celem badań była ocena jakości uprawy dwiema maszynami w warunkach różnej głębokości spulchniania gleby, którą sprawdzono podczas uprawy pożniwnej oraz podczas uprawy podstawowej. Wyznaczono wskaźniki jakości pracy pługa zębowo-talerzowego i porównano ze wskaźnikami jakości pracy agregatu. Zastosowanie narzędzi z elementami roboczymi, rozmieszczonymi na dwóch różnych poziomach głębokości roboczej, zapewnia dobrą jakość uprawy dwuwarstwowej, łączącej głęboszowanie z płytkim odwracaniem.

EN

The basic rule of ecological farming is "to loosen deep and turn over shallow". Untill now for two-layer tillage the mouldboard ploughs with subsoilers were used. In the Industrial Institute of Agricultural Machines new structural solutions were developed to the machines and implements for two-layer soil tillage operation. The object of studies was to evaluate soil tillage with two machines at different depths of loosening soil, tested during post-harvest tillage of soil as well as during basie tillage operations. Indices of work quality for a tooth-disc plough were determined and compared to work quality indices of a tillage aggregate. Application of the implements with working elements located at two different levels of working depth ensured good quality of two-layer soil tillage which combined subsoiling tillage with the shallow turnover.

8

Analiza wytrzymałościowa zęba trzonowego i jego implantu

Gąsiorek D., Guzik A., Rogalski D.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

|

2006

|

z. 30

53-58

PL

W pracy przedstawiono analizę wytrzymałościową zęba trzonowego i implantu. Model wykonano jako 2D, a do analizy wytrzymałościowej użyto programu Ansys. Metoda elementów skończonych pozwoliła na wyznaczenie naprężeń i deformacji zęba i implantu pod wpływem działających na nie sił.

EN

Paper presents strength analysis of molar tooth and implant. Model was created as the 2D model, and for the strength analysis the Ansys program was used. Finite element method enabled to determine stresses and deformation of tooth and implant under the influence of applied forces.

9

Mechanical properties of human tooth approximated with overdamped oscillators

Malinowska J., Sowińska M., Borgieł W.

Acta of Bioengineering and Biomechanics

|

2005

|

Vol. 7, no. 1

59-67

EN

Numerical calculations and analysis of the tension states in hard tissues of tooth are very interesting and important issues from the orthodontist's point of view. Orthodontic methods of treatment can have a dramatic effect on children's long-term dental health and facial appearance. Research done in this field shows that due to understanding mechanics of rnasticatory organ it IS possible to attain the intentional aim of therapy in shorter time and avoid to undesired complications. The behaviour of alveolodental ligament when the force was applied allows the authors to look at human tooth affected by damped harmonic oscillator. In this study, periodontograph was successfully achieved from harmonic oscillators properties.

10

Analiza odkształceń zębów pasa zębatego na łuku opasania koła pasowego

Domek G., Kowalski A.

Mechanik

|

2004

|

R. 77, nr 2

88-89

11

In vitro examination of human teeth using ultrasound and X-ray diffraction

Gawda H., Sękowski L., Trębacz H.

Acta of Bioengineering and Biomechanics

|

2004

|

Vol. 6, no. 1

41-49

EN

The aim of this paper was to find whether an ultrasound velocity along a whole tooth reflects variety of its morphology and properties and to compare thc results of ultrasonic measuremcnts with X-ray diffraction data from a large area of tooth. 100 kHz pulses were transmitted in longitudinal direction of ectracted teeth. A significant variation of velocity in teeth from diffcrent donors was statwd (from 3200 m/s to 4200 m/s). The velocity was influenced both by the age of donors and the type of a tooth. For a given individual, the grcatest difference was revealed between incisors and canine teeth. Considering X-ray diffraction results, a difference in size of crystallites between teeth was found. In an enamel, the size of crystallites ranged from 20 nm to 50 nm, and in dentin - from 5.5 nm to 39 nm. The size of crystailites in dentin was positively correlated with the ultrasound velocity.

12

Equine masticatory organ. Part III

Kuryszko J.K., Łyczewska-Mazurkiewicz S.

Acta of Bioengineering and Biomechanics

|

2004

|

Vol. 6, no. 1

25-30

EN

The masticatory system, which is also referred to as the stomatognathic system, consists of the temporomandibular joints, dentoalveolar apparatus, dentodental junctions and the neuromuscular complex. This articlc prcsents the relations between various joints under both physiological and pathological conditions.

13

Analiza rozmieszczenia naprężeń w zębie pasa zębatego w procesie sprzęgania z zębem koła pasowego

Domek G., Macko M.

Mechanik

|

2003

|

R. 76, nr 2

77-79

14

In vitro investigations of the heat transfer phenomena in human tooth

Preiskorn M., Żmuda S., Trykowski J., Panas A., Preiskorn M.

Acta of Bioengineering and Biomechanics

|

2003

|

Vol. 5, no. 2

23-36

EN

An experimental stand for in vitro investigations of transient heat transfer phenomena in human teeth is described. The stand has been designed to reproduce thermal conditions of the environment of the oral cavity. In this particular case. special attention was paid to simulation of the heat transfer by the pulp. Appropriate modifications have been introduced into the experimental set-up. The measurements confirmed that they enabled very close replication of real conditions. The paper presents results of test measurement and results of preliminary numerical calculations for the heat conduction in incisor tooth. In this particular case, effects of exposition of the tooth to radiation of two different dental polymerisation lamps have been compared. As a result the methodology of verification of theoretical modelling of heat transfer and heat transmission-related effects in teeth have been developed and described.

15

Analiza numeryczna stanu wytężenia niejednorodnych struktur materiałowych w problemach stomatologii

Kierklo A., Tribiłło R., Walendziuk A.

Zeszyty Naukowe Politechniki Białostockiej. Budownictwo

|

2002

|

Z. 22

131-139

PL

Wykorzystując metodę elementów skończonych, zbadano wpływ wypełnienia algamatowego i kompozytowego na powierzchni zgryzowej na rozkład naprężeń w rejonie szyjki ludzkiego dolnego zęba przedtrzonowego z ubytkiem niepróchnicowego pochodzenia.

EN

The aim of this study was to use the Finite Element Method to examine the that an existing occlusal amalgam or composite restoration might have on the stress patterns at the cervical region with non-carious lesion of a human lower premolar. The hypothesis used was that the presence of a Class I restoration would effect unfavourable cervical stress distribution under occlusal loading. It was found that the greatest concentration of the highest stresses was in the angular corner and the dentine adjacent a deep cervical cavity, whereas the distribution of stresses arround the shallow one was the better. In conclusion, the state of cervical stresses which was proved in this study was proved in this study was independent on the correctly modeled occlusal filling, thanks to the joint action of this restoration with tooth's structures.

16

Destrukcja wypełnień przyszyjkowych uwarunkowana efektem odkształcenia objętościowego i postaciowego

Kierklo A., Tribiłło R., Walendziuk A.

Zeszyty Naukowe Politechniki Białostockiej. Budownictwo

|

2000

|

Z. 20

69-74

PL

Praca przedstawia analizę destrukcji wypełnień ubytków przyszyjkowych zębów. Dokonano w niej oceny wpływu rozkładu naprężeń na powierzchniach kontaktu tkanek i wypełnienia na ich trwałość.

EN

The analysis of cervical restorations destrucyion of tooth has been studied in the work. The influence of stress distribution on the bond surfaces has been evaluated in the light of restorations durability.