TY - JOUR. T1 - Imperfect hybrid layers created by an aggressive one-step self-etch adhesive in primary dentin are amendable to biomimetic remineralization in vitro. AU - Kim, Jongryul. AU - Vaughn, Ryan M.. AU - Gu, Lisha. AU - Rockman, Roy A.. AU - Arola, Dwayne D.. AU - Schafer, Tara E.. AU - Choi, Kyoung Kyu. AU - Pashley, David H.. AU - Tay, Franklin R.. PY - 2010/6/15. Y1 - 2010/6/15. N2 - Degradation of hybrid layers created in primary dentin occurs as early as 6 months in vivo. Biomimetic remineralization utilizes bottom-up nanotechnology principles for interfibrillar and intrafibrillar remineralization of collagen matrices. This study examined whether imperfect hybrid layers created in primary dentin can be remineralized. Coronal dentin surfaces were prepared from extracted primary molars and bonded using Adper Prompt L-Pop and a composite. One-millimeter-thick specimen slabs of the resin-dentin interface were immersed in a Portland cement-based remineralization medium that contained ...
TY - JOUR. T1 - Site specific properties of carious dentin matrices biomodified with collagen cross-linkers. AU - Bedran-Russo, Ana K.. AU - Karol, Sachin. AU - Pashley, David H.. AU - Viana, Grace. N1 - Copyright: Copyright 2013 Elsevier B.V., All rights reserved.. PY - 2013/10. Y1 - 2013/10. N2 - Purpose: To assess in non-cavitated carious teeth the mechanical properties of dentin matrix by measuring its reduced modulus of elasticity and the effect of dentin biomodification strategies on three dentin matrix zones: caries-affected, apparently normal dentin below caries-affected zone and sound dentin far from carious site. Methods: Nano-indentations were performed on dentin matrices of carious molars before and after surface modification using known cross-linking agents (glutaraldehyde, proanthocyanidins from grape seed extract and carbodiimide). Results: Statistically significant differences were observed between dentin zones of demineralized dentin prior to surface biomodification (P, 0.05). ...
This study was conducted to compare the shear bond strengths of composite resin bonded to Er:YAG laser or bur-prepared dentin surfaces using three self-etching adhesive systems. The occlusal surfaces of 120 human third molars were ground flat to expose dentin. The dentin was prepared using either a carbide bur or an Er:YAG laser at 350 mJ/pulse and 10 Hz (fluence, 44.5 J/cm2). Three different self-etching adhesive systems were applied: iBond™, Xeno III™ and Clearfil SE Bond™. Rods of composite resin were bonded to dentin surfaces and shear bond tests were carried out. Both dentin surfaces after debonding and resin rods were observed using a scanning electron microscope. When the Xeno III™ was used, no difference was observed on shear bond strength values when bur and Er:YAG laser were compared. When using iBond™ and Clearfil SE Bond™, bond strength values measured on Er:YAG-laser-prepared surfaces were lower than those observed on bur-prepared surfaces. The absence of smear layer formation
TY - JOUR. T1 - Comparative post irrigation evaluation of calcium loss and its effect on microhardness of radicular dentin. AU - Khosla, Manak. AU - Mala, Kundabala. AU - Shenoy, Ramya. PY - 2017/10/1. Y1 - 2017/10/1. N2 - This study was conducted to compare calcium loss and microhardness reduction of radicular dentin following treatment with 17% EDTA, 10% citric acid, 5% maleic acid, and MTAD, by estimating calcium loss, and radicular dentin microhardness by using Atomic absorption spectrophotometry and by Vickers hardness tester. The results were statistically evaluated using one way ANOVA test and performed at 95% level of confidence and Spearmans correlation test was applied to determine correlation between calcium liberation and radicular dentin microhardness. All the experimental chelating agents bring about calcium loss and reduction in microhardness from radicular dentin.Study concluded that at 5 minutes, 5% maleic acid as a chelating agent causes the maximum calcium loss and ...
OBJECTIVES: The submicron hiatus represents a potential space between the base of the collagen network and the mineralized dentin when dentin is acid-etched for bonding. These spaces were observed in SEM studies after acid-etched dentin specimens were critical point dried or dehydrated in hexamethyldisilasane. However, they have never been identified in TEM studies of dentin hybrid layers. This study critically examined the cause of submicron hiati formation using a silver staining technique to measure nanoleakage. METHODS: Two multi-step, total-etch adhesives (One-Step, Bisco; Single Bond, 3M) and two single-step, self-etching adhesives (Prompt L-Pop, ESPE; One-Up Bond F, Tokuyama) were examined. Flat dentin surfaces were bonded with these adhesives and a lining composite. In each adhesive group, 0.8mm thick slabs from the same bonded tooth were coated with nail varnish applied 1mm from the bonded interfaces. The varnish was either left to dry completely for 10min before immersing in 50wt% ...
Purpose: To assess the effect of different peri- and intertubular dentin mineralization conditions and etching on shear bond strength in vitro. Materials and Methods: One hundred fifty crowns of extracted bovine incisors were embedded in resin and ground to expose the buccal coronal dentin. Sixty specimens were subjected to a demineralizing solution (DS) and another 60 teeth to a bacterial-based laboratory caries model (S. mutans, SM). Thirty specimens of each demineralization protocol (DS and SM) were randomly selected and remineralized (-R). Thirty sound dentin specimens served as control (C). Resin composite buildups (Tetric) were bonded after application of one of the following adhesives: a one-step self-etching adhesive (Xeno III), and a self-etching adhesive (Syntac Classic) without (three-step) and with prior additional 35% phosphoric acid etching (etch-and-rinse, four-step). Teeth were subjected to shear bond strength testing in a universal testing device at a crosshead speed of 0.5 ...
Introduction. The mechanism for adhesive bonding to dental substrates, especially to dentin, has been extensively studied in the last few decades. The establishment of effective interlocking occurs when the adhesive penetrates into the intratubular and intertubular dentin so that resin penetration into the conditioned dentin results in the formation of intratubular resin tags and a hybrid layer.1 Micromechanical attachment is the most important mechanism of resin adhesion to dentin. However, there are several factors that can affect hybrid layer and resin tag formation, such as acid-etching, the moisture conditions of the substrate, and adhesive and dentin depth.2. During dentin acid-etching, the mineral content of the dentin surface is removed, and the collagen fibrils remain supported by water.3 The moist bonding technique prevents the collagen fibers from collapsing and provides stability to the collagen, thus enabling greater infiltration of adhesive monomers.4 However, some studies have ...
Statement of the Problem: Low pH of self-etch adhesives might cause suboptimal polymerization. Purpose: This study aimed to evaluate the effect of dentin depth (deep and superficial) on polymerization efficacy of two self-etch adhesives, with different pH by means of Knoop hardness test. Materials and Method: In this in vitro study, sixty sound molars were used to prepare 30 superficial dentin and 30 deep dentin specimens. Dentin specimens of each depth were randomly distributed into two equal subgroups (N=15) and bonded by either Adper Prompt L-Pop (strong self-etch adhesive) or Adper Easy Bond (mild self-etch adhesive). Knoop hardness test was employed to evaluate degree of cross-linking of the adhesives. Data were analyzed with SPSS 16, using two-way ANOVA to compare mean hardness values of the study groups (p | 0.05). Results: There was no interaction effect between dentin depth and the type of adhesive (p = 0.36). Regardless of dentin depth, hardness of Adper Easy Bond was significantly higher than
TY - JOUR. T1 - The effect of flowable composite lining and dentin location on microtensile bond strength and internal fracture formation. AU - Kominami, Nao. AU - Shimada, Yasushi. AU - Hosaka, Keiichi. AU - Luong, Minh Nguyet. AU - Yoshiyama, Masahiro. AU - Sadr, Alireza. AU - Sumi, Yasunori. AU - Tagami, Junji. PY - 2019. Y1 - 2019. N2 - The objective of this study was to determine the effect of flowable composite lining and dentin location on internal dentin fracture formation in the microtensile bond strength (MTBS) test using swept-source optical coherence tomography (SS-OCT). MTBS test beams (1.0×1.0 mm) were prepared from human superficial and deep dentin, which was bonded with a self-etch adhesive (Clearfil SE Bond) and hybrid composite resin (Clearfil AP-X), with or without flowable lining (Clearfil Majesty ES-Flow). We tested 4 groups according to placement technique (with vs. without flowable liner) and dentin (superficial vs. deep) locations. Cross-sectional 2D images of the bonded ...
Microtensile bond strength of Resin composite to Normal dentin and Caries - affected dentin with total-etch and self-etch bonding adhesives before and after thermocycling
The influence of chlorhexidine on the remineralization of demineralized dentine Duck-Su Kim , Jongryul Kim , Kyoung-Kyu Choi and Sun-Young Kim Journal of Dentistry, 2011-12-01, Volume 39, Issue 12, Pages 855-862, Copyright © 2011 Elsevier Ltd Abstract Objectives To examine the differences in the amounts of bound chlorhexidine (CHX) on demineralized dentine blocks and to investigate the different aspects of remineralization of demineralized dentine according to different concentrations of CHX. Methods Dentine blocks (2 mm × 7 mm × 0.9 mm) were demineralized in 0.2 M formic acid solution. Amount of bound CHX on the dentine blocks was measured on a spectrophotometer after the dentine block was soaked in 0.02%, 0.2%, or 2% CHX solutions for 1 min. The change in elastic modulus of dentine block stored in simulated body fluids was measured at 0 (baseline), 2, 4, and 6 weeks after storage. The micromorphological aspects of the samples were observed using a field emission scanning electron microscope ...
Definition of primary dentin in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is primary dentin? Meaning of primary dentin as a legal term. What does primary dentin mean in law?
The aim of this study was to examine the morphology of the hybrid layer (HL) of bonded water-stored specimens after different chemical pre-treatments of dentin. Materials and methods. Twenty-seven recently extracted human molars were selected. Fifty-four dentin disks in middle/deep dentin were obtained with a slow speed saw with a diamond-impregnated disk under water lubrication. Smear layers were created with 180 grit silicon carbide under running water for 1 min. Different pre-treatments of dentin were: Group (1) no treatment; Group (2) 35% H3PO4 etch for 15 s followed by 10% glutaraldehyde for 120 s; Group (3) 37% H3PO4 etch for 15 s followed by 5% NaOCl for 120 s. Three dentin bonding agents (DBAs), Prime and Bond NT (P and B), AdmiraBond (AB), and Clearfil SE Bond (SEB) were applied in association with a resin composite following the manufacturers directions. Each specimen was then longitudinally sectioned and polished with wet SiC papers (up to #4000 grit). Impressions of the polished ...
The use of protein cross-linking agents during bonding procedures has been recently proposed to improve bond durability. This study aimed to use zymography and in situ zymography techniques to evaluate the ability of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) cross-linker to inhibit matrix metalloproteinase (MMP) activity. The hypotheses tested were that: (1) bonding procedures increase dentin gelatinolytic activity and (2) EDC pre-treatment prevents this enzymatic activity. The zymographic assay was performed on protein extracts obtained from dentin powder treated with Optibond FL or Scotchbond 1XT with or without 0.3M EDC pre-treatment. For in situ zymography, adhesive/dentin interfaces were created with the same adhesives applied to acid-etched dentin slabs pre-treated or not with EDC conditioner. Zymograms revealed increased expression of dentin endogenous MMP-2 and -9 after adhesive application, while the use of EDC as a primer inactivated dentin gelatinases. Results of in situ zymograpy
TY - JOUR. T1 - Demonstration of type III collagen in the dentin of mice. AU - Nagata, Kengo. AU - Huang, Yu Hsin. AU - Ohsaki, Yasuyoshi. AU - Kukita, Toshio. AU - Nakata, Minoru. AU - Kurisu, Kojiro. PY - 1992/1/1. Y1 - 1992/1/1. N2 - It has been reported that, although type III collagen is present in human dentin where there is dentinogenesis imperfecta and in reparative dentin, it is absent in normal dentin. In a preliminary study, however, we observed evidence showing that small amounts of fibers showing positive labeling for type III collagen are present in the molars of normal mice. In the present study, in order to localize type III in normal dentin, immunofluorescent and immunoelectron microscopic examinations of the molars of normal mice were carried out using affinity-purified antibodies to mouse type III and type I collagen. The fibers positive for type III collagen were much more frequently observed in the root than in the crown. These fibers ran in peritubular dentin or near that ...
TY - JOUR. T1 - The effects of radicular dentine treated with double antibiotic paste and ethylenediaminetetraacetic acid on the attachment and proliferation of dental pulp stem cells. AU - Kim, Ki Wan. AU - Yassen, Ghaeth H.. AU - Ehrlich, Ygal. AU - Spolnik, Kenneth. AU - Platt, Jeffrey A.. AU - Windsor, L. Jack. PY - 2015/10/1. Y1 - 2015/10/1. N2 - This study explored the effects of dentine treated with two concentrations of double antibiotic paste (DAP) and ethylenediaminetetraacetic acid (EDTA) on the attachment and proliferation of dental pulp stem cells (DPSCs). Materials and Methods: Radicular dentine samples were prepared with identical dimensions and randomized into six groups (n = 4). Four groups were treated with double antibiotic paste (DAP) at concentrations of 500 mg ml-1 or 1 mg ml-1 with or without EDTA. The other two groups were treated with EDTA only or received no treatment. DPSCs were seeded on each dentine sample (10 000 cells per sample). Lactate dehydrogenase activity ...
In this study, a fluorescence technique was developed for visualization of dentin using confocal laser scanning microscopy (CLSM). Eighteen extracted human teeth were used: 13 showing no clinical signs of caries and 5 with visually apparent decay. Preliminary study: All teeth were horizontally sectioned to approx. 200 micrometers thickness and pre-treated as follows: no pretreatment; vacuum only; ultrasonication only; sodium hypochlorite (NaOCl) only; vacuum and NaOCl; ultrasonication and NaOCl; or vacuum, ultrasonication and NaOCl. Samples were stained with Rhodamine 123 fluorescent dye at a concentration of 10-5 M in phosphate buffer saline for 1 to 24 hours. Caries study: Dentin surfaces, some with pre-existing caries, were visualized using CLSM. Most dentin tubules in sound dentin appeared open using CLSM, but most dentin tubules in carious dentin appeared closed or narrowed. Surface images obtained using CLSM were similar to those seen by SEM, but additional subsurface imaging was possible ...
Introduction: Oxidant bleaching agents may induce several alterations on mineralized teeth tissues. Our aim is to study, at the ultrastructural level, mechanical modifications induced on dentin after exposure to different bleaching agents. Methods: Nanoindentation performed with atomic force microscopy was used to measure changes in dentin stiffness as well as the adhesion force between the tip and the tissue both in intertubular and peritubular dentin. For each specimen, dentin localization, and bleaching agent, 100 independent nanoindentations were performed. Carbamide peroxide (30%) and hydrogen peroxide (35%) were used as bleaching agents. Results: A significant reduction of both stiffness and adhesion force was found for both carbamide and hydrogen peroxide in peritubular and intertubular dentin. Conclusions: The use of bleaching agents led to a significant reduction in dentin local (at the nanoscale) mechanical properties. ...
Dentin is a calcified tissue of the body. Dentin, enamel, cementum and pulp, are the four major components that make up the teeth. It is often covered by enamel on the crown and cementum of the root and surrounds the tooths pulp. Dentin is comprised of 45% hydroxylapatite, 33% organic material and 22% water. Dentin is yellow in its appearance and greatly affects the tooths color because of the enamels translucency. Dentin is less mineralized and less brittle in comparison to enamel. It is also necessary for the support of the enamel. Dentin has a score of 3 on the Mohs scale of mineral hardness. Dentin forms throughout life and is very sensitive.. Dentinal sclerosis or transparent dentin-sclerosis of primary dentin is the regressive alteration in teeth caused by the calcification of the dentinal tubules. It can occur as a result of cavities, an abrasion or as part of the normal aging process. ...
The influence of dentin permeability on transdentinal LED light propagation should be evaluated since this kind of phototherapy may further be clinically used to stimulate the metabolism of pulp cells, improving the healing of damaged pulps. This study evaluated the influence of the dentin permeability on the transdentinal LED light (630 nm) transmission. Forty-five 0.5-mm-thick dentin disks were prepared from the coronal dentin of extracted sound human molars. An initial measurement of transdentinal LED light transmission was carried out by illuminating the discs in the occlusal-to-pulpal direction onto a light power sensor to determine light attenuation. The discs were treated with EDTA for smear layer removal, subjected to analysis of hydraulic conductance, and a new measurement of transdentinal LED light transmission was taken. Spearmans correlation coefficient was used for analysis of data and showed a weak correlation between dentin permeability and light attenuation (coefficient = 0.19). ...
Microtensile bond strength was evaluated in two separate experiments, performed in two different laboratories, following the same bonding procedures and using same materials. The teeth were sectioned under water cooling coronally to remove occlusal enamel and to expose flat dentin surface, and at the dentin-enamel junction. Exposed dentin surface was ground with 180-grit abrasive paper to create uniform smear layer, and the teeth were randomly divided into two groups. In the control specimens, the adhesives were used as recommended by the manufacturer. Briefly, the dentin surface was first acid-etched with 37% phosphoric acid for 15 s, rinsed, and gently dried with compressed air to achieve slightly dry surface. Then water was scrubbed into the surface with cotton pellet for 30 s and gently dried, leaving the surface slightly moist, and 1-step etch-and-rinse adhesive Scotchbond 1XT was used as per manufacturers recommendations, and polymerized with 20 s blue light irradiation (Elipar Freelight ...
Dentin hypersensitivity is a painful response to a non-noxious stimulus applied to exposed dentin. Two processes may expose dentin: loss of enamel and/or loss of cementum. Loss of enamel occurs by attrition associated with occlusal function, by abrasion from dietary components or incorrect toothbrushing, or by erosion associated with environmental or dietary components, particularly acids. Exposure of root dentin is also multifactorial. Periodontal disease with gingival recession, some forms of periodontal surgery, and overzealous brushing are important etiological factors that expose root dentin. In addition, in some individuals the cementum and enamel do not meet, exposing an area of dentin. The management of this condition requires a good understanding of the complexity of the problem as well as the variety of treatments available. Some authors report that lasers may provide reliable and reproducible treatment of dentin hypersensitivity. One concern for laser safety is that the heat produced ...
TY - JOUR. T1 - Influence of NaOCl deproteinization on shear bond strength in function of dentin depth. AU - Toledano, Manuel. AU - Perdigão, Jorge. AU - Osorio, Estrella. AU - Osorio, Raquel. PY - 2002/8/1. Y1 - 2002/8/1. N2 - Purpose: To determine the influence of NaOCl application on shear bond strengths (SBS) to superficial and deep dentin, using Prime & Bond 2.1. Materials and Methods: Superficial and deep dentin was exposed in 40 extracted third molars by sectioning the occlusal surface immediately under the enamel-dentin junction or close to the pulp chamber. After polishing the dentin disks (600-grit SiC), they were assigned to two groups: (1) 36% orthophosphoric acid for 15 seconds, or (2): 36% orthophosphoric acid for 15 seconds followed by 5% sodium hypochlorite (NaOCl) for 2 minutes. The dentin adhesive was applied as per manufacturers instructions, followed by TPH resin-based composite. The specimens were stored in water for 24 hours at 37°C and thermocycled x500 and SBS were ...
PURPOSE: To evaluate microtensile bond strength and interfacial nanoleakage expression of adhesive interfaces created by XP-Bond on human deproteinized dentin immediately after bonding and after 6 months of artificial aging. MATERIALS AND METHODS: Noncarious human molars were selected, middle/deep dentin substrates were exposed, and either assigned to group 1 (XP-Bond applied on collagen-depleted dentin) or to group 2 (XP-Bond applied in accordance with manufacturers instructions). In group 1, the etched dentin surface was treated with 10% NaOCl for 60 s to remove the exposed demineralized organic matrix before XP-Bond application. Composite/dentin beams were obtained in accordance with the microtensile nontrimming technique and either pulled to failure after 24 h or after 6 months artificial aging. Data were analyzed with two-way ANOVA and Tukeys post-hoc test (p , 0.05). Interfacial nanoleakage evaluation was performed on additional adhesive interfaces to quantify the amount of silver ...
Dentin (/ˈdɛntɪn/) (American English) or dentine (/ˈdɛnˌtiːn/ or /ˌdɛnˈtiːn/) (British English) (Latin: substantia eburnea) is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by enamel on the crown and cementum on the root and surrounds the entire pulp. By weight, 45% of dentin consists of the mineral hydroxylapatite, 33% is organic material, and 22% is water. Yellow in appearance, it greatly affects the color of a tooth due to the translucency of enamel. Dentin, which is less mineralized and less brittle than enamel, is necessary for the support of enamel. Dentin rates approximately 3 on the Mohs scale of mineral hardness. Dentinal sclerosis/transparent dentin-sclerosis of primary dentin is regressive alteration in tooth characterized by calcification of dentinal tubules. It can occur as a result of injury to dentin by caries or abrasion, or as part of the normal aging process. The ...
TY - JOUR. T1 - In vitro evaluation of dentin tubule occlusion for novel calcium lactate phosphate (CLP) paste. AU - Yang, Jen Chang. AU - Hu, Hsin Tai. AU - Lee, Sheng Yang. AU - Hsieh, Sung Chih. AU - Huang, Pei Chi. AU - Ma, Chen Feng. AU - Ji, Dian Yu. AU - Chang, Liang Yu. AU - Teng, Nai Chia. PY - 2017. Y1 - 2017. N2 - Introduction: The objective of this in vitro study is to evaluate the effective and long-term occlusion of dentinal tubules using a novel calcium lactate phosphate (CLP) based desensitizing agent. Methods: Dentin disks (n = 9) were pre-etched using 1 M lactic acid for 30 s and individually treated with Colgate® Pro-Relief™ paste, CLP paste, and double distilled water (ddH2O) by a rubber-cupped handpiece. Dentin disks were analyzed under optical micrographs for pre-treatment, directly after treatment, and 14 days post-treatment. One-way ANOVA and post-hoc Tukeys test were used to determine whether there were any statistically significant differences in dentinal tubule ...
PubMed journal article Gene expression patterns of murine dentin matrix protein 1 (Dmp1) and dentin sialophosphoprotein (DSPP) suggest distinct developmental functions in viv were found in PRIME PubMed. Download Prime PubMed App to iPhone, iPad, or Android
The purpose of this study was to determine the uptake of fluoride by dentin after pulsed Nd:YAG laser irradiation. Under SEM examination dentin lased by pulsed Nd:YAG laser appeared to be melted; there were no changes of calcium and phosphorus levels. Dentin irradiated by pulsed Nd:YAG laser and treated with 38% Ag(NH3)2F showed greater uptake and deep penetration of fluoride than topical application of fluoride alone, SEM examination revealed that CaF2-like and Ag3PO4-like deposits were formed on the dentin surface. These results suggested that pulsed Nd:YAG laser irradition could improve the absorption of fluoride in dentin ...
Objectives. Contemporary adhesives lose their bond strength to dentin regardless of the bonding system used. This loss relates to the hydrolysis of collagen matrix of the hybrid layers. the preservation of the collagen matrix integrity is a key issue in the attempts to improve the dentin bonding durability.Methods. Dentin contains collagenolytic enzymes, matrix metalloproteinases (MMPs) and cysteine cathepsins, which are responsible for the hydrolytic degradation of collagen matrix in the bonded interface.Results. the identities, roles and function of collagenolytic enzymes in mineralized dentin has been gathered only within last 15 years, but they have already been demonstrated to have an important role in dental hard tissue pathologies, including the degradation of the hybrid layer. Identifying responsible enzymes facilitates the development of new, more efficient methods to improve the stability of dentin-adhesive bond and durability of bond strength.Significance. Understanding the nature and ...
Objectives: The purpose of this study was to evaluate the effects of load cycling on nanoleakage of occlusal flat surface or cervical restorations bonded with three self-etching priming systems and a single bottle system. Methods: The dentin bonding systems used in this study were Clearfil SE Bond, Unifil Bond, Prompt L-Pop and Single Bond. Flat occlusal dentin surfaces and cervical cavities from extracted human molars were bonded with one of the dentin bonding systems. After load cycling of 90N for 5000 cycles, samples were immersed in a 50% w/v solution of silver nitrate for 24h, and exposed to photodeveloping solution for 8h. Specimens were sectioned, mounted on stubs, carbon-coated and observed in a Field Emission-SEM using backscattered electron mode. One-way ANOVA was used for statistical analysis of the leakage scores. Results: FE-SEM images showed that samples subjected to load cycling had leakage patterns similar to non-load-cycled samples for all dentin bonding systems. Load cycling ...
Concentrations of calcium and phosphorus were measured in the neonatal dentine of 11 crabeater and 11 Weddell seal postcanine teeth with an energy-dispersive x-ray analyser. The extent of variation in elemental concentrations in different parts of the tooth, differences between species and individuals, and whether variation in elemental concentrations can provide information about dentine deposition mechanisms were assessed. No consistent patterns in elemental deposition in different parts of the tooth were found, but there were differences in concentrations between and within species. Post-natal dentine is composed of layers that appear alternately bright and dark in backscattered electron images. The elemental composition of neonatal dentine was closer to the dark bands than to those that appeared bright. It is suggested that the composition of neonatal dentine is more similar to the dark than the bright layers of dentine because of nutritional stresses that were occurring during mineral ...
Purpose: To examine the effects of collagenase and esterase activity on the microtensile bond strength and nanoleakage at the resin-dentin interfaces of two adhesive systems: a total-etch adhesive (Single Bond 2: SB) and a self-etch adhesive (Clearfil SE Bond: SE). Methods: Resin composites were bonded to the occlusal dentin surfaces of extracted human premolars with either SB or SE. The bonded teeth were sectioned into beams and assigned to one of four storage conditions: phosphate buffer solution (24 hours), phosphate buffer solution (4 weeks), collagenase solution (4 weeks), or esterase solution (4 weeks). Microtensile bond strength was evaluated and analyzed by two-way ANOVA. Failure mode was analyzed under SEM, and nanoleakage was examined with TEM. Results: The bond strength of SE was superior to that of SB after 4-week storage in three aqueous solutions. Collagenase and esterase solutions did not decrease the bond strength of SB any more than the phosphate buffer solution (P, 0.05). In ...
Aim: This study evaluated the influence of dentin wettability on the immediate and extended microtensile bond strength (mTBS) of a universal adhesive system used in the etch-and-rinse strategy. Methods: Twenty human third molars were selected and divided into four groups according to the adhesive system and dentin wettability. The mTBS values of each group were registered 24 h and one year after adhesive system application and resin composite block build-up (n=30). Data were analyzed by the t-test (p,0.05). Results: When both adhesive systems were compared, there was no statistically significant difference when they were applied following wet bonding (p,0.05). However, the dry bonding reduced μTBS values of the Adper Single Bond 2 adhesive (p,0.05). Regarding storage time, both groups presented similar μTBS values at 24 h and one year (p,0.05). Conclusions: Therefore, the Scotchbond Universal Adhesive can be applied to dry or wet dentin without compromising the etch-and-rinse bonding quality ...
TY - JOUR. T1 - Enamel and Dentin Bond Durability of Self-Adhesive Restorative Materials. AU - Latta, Mark A.. AU - Tsujimoto, Akimasa. AU - Takamizawa, Toshiki. AU - Barkmeier, Wayne W.. PY - 2020/1/1. Y1 - 2020/1/1. N2 - PURPOSE: To use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the durability of adhesion of self-adhesive restorative materials compared to composite resin bonded with a universal adhesive. MATERIALS AND METHODS: A universal adhesive, Prime & Bond Active, was used in self-etch mode to bond Z-100 composite resin to enamel and dentin. Three commercially available restorative materials and one experimental material with self-adhesive properties, Activa (A), Fuji II LC(F), and Equia Forte (E) and ASAR-MP4 (S) were also bonded to enamel and dentin. The SBS and SFS were determined for all materials. A staircase method was used to determine the SFS with 10 Hz frequency for 50,000 cycles or until failure occurred. RESULTS: On enamel, S generated ...
This study compared the microtensile bond strength (BS) and the micromorphology of resin-dentin interface (MI) of a conventional adhesive to two-steps etch-and-rinse bonding agents after 1 year of water storage. Twenty-eight human third molars were used (n = 7). Teeth were divided into four groups (GCB: Gluma Comfort Bond; OPB: OptiBond FL; OCB: One Coat Bond SL; PUB: Peak Universal Bond). Specimens were tested in tension after 24 h or 1 year of water storage. Dentin BS strength data were analyzed by split-plot two-way ANOVA followed by Tukey-Kramer tests (α = 0.05). Water-storage for 1 year significantly decreased BS for OCB; however, no significant difference was noted between OCB and GCB and PUB adhesives after 1 year of water-storage. OPB showed the highest BS values at both storage times. All adhesives formed a hybrid layer with resin tags, and both interfacial structures were maintained after 1 year. However, degradation signals within interfacial structures were observed only for the adhesive
Objective. To determine the translucency of human and bovine enamel and dentin using reflection spectrophotometers. Material and Methods. The color of intact human and bovine enamel and dentin specimens was measured over a white and a black plasticine backing using two spectrophotometers with different aperture sizes; translucency parameter (TP) and contrast ratio (CR) were calculated. Plasticine was used as backing because the specimens were not uniform. The TP values of five composite resins measured over the backings of plasticine and reflectance standards were also determined. Results. There were no significant differences between the TP values of the composite resins measured over the backings of plasticine and reflectance standards (p,0.05). Mean TP values of 1 mm thick bovine enamel, bovine dentin, human enamel and human dentin were 14.7, 15.2, 18.7, and 16.4, respectively, based on the 3 mm round aperture. There were significant correlations between the TP values measured by the two ...
TY - JOUR. T1 - Shear bond strength of the Tenure Solution dentin bonding system.. AU - Barkmeier, Wayne W.. AU - Cooley, R. L.. PY - 1989/10. Y1 - 1989/10. N2 - A liquid solution of an oxalate bonding system containing NTG-GMA and PMDM has become commercially available. The bond strength of this oxalate adhesive (Tenure Solution) to dentin was determined by bonding composite resin cylinders to extracted teeth. The bond strengths obtained in this study are compared to the bond strengths obtained in earlier studies with the first and second generation oxalate adhesives whose components were supplied as powders and required mixing. The oxalate solutions developed significantly higher bond strengths than the original powder type systems.. AB - A liquid solution of an oxalate bonding system containing NTG-GMA and PMDM has become commercially available. The bond strength of this oxalate adhesive (Tenure Solution) to dentin was determined by bonding composite resin cylinders to extracted teeth. The ...
Objectives: To develop prototype rotary selective dentin caries excavators and to demonstrate their ability to remove only carious dentin in extracted teeth. Method and materials: Milled polymer prototype and formed wire loop prototype burs were made. They were tested on normal dentin with standardized force application and compared to carbide burs for ability to cut by weighing three extracted teeth at pre- and postcutting for each prototype version. They were tested on carious dentin of three teeth for each prototype version. The resulting excavated surfaces were analyzed with dentin caries dye, the teeth were decalcified and examined histologically, and the used prototypes were examined in light and scanning electron microscopes. Results: For both prototypes, noncarious teeth did not lose weight from prototype instrumentation, but each lost 9 or 10 mg after instrumentation with the control carbide bur. Both prototypes quickly removed carious dentin in each of the carious teeth until a ...
TY - JOUR. T1 - Micro-tensile bond strength of self-etching primer adhesive systems to human coronal carious dentin. AU - Doi, J.. AU - Itota, T.. AU - Torii, Y.. AU - Nakabo, S.. AU - Yoshiyama, M.. PY - 2004/10. Y1 - 2004/10. N2 - The aim of this study was to evaluate the micro-tensile bond strengths of three self-etching primer adhesive systems to normal dentin (ND), caries-affected dentin (CAD) and caries-infected dentin (CID). Human extracted molars with caries were used, and flat dentin surfaces ground by 600-grit SiC paper were prepared. The surfaces were dyed using Caries-Detector solution, treated with Clearfil SE Bond, Mac-Bond II and UniFil Bond, and then covered with resin composites according to manufacturers instructions. After immersion in 37°C water for 24 h, the teeth were serially sectioned into multiple slices. Each slice was distinguished into ND, CAD and CID groups by the degree of staining, and the bond strength was measured in a universal testing machine. Scanning ...
TY - JOUR. T1 - Effect of ammonium hexafluorosilicate on dentin tubule occlusion for the treatment of dentin hypersensitivity. AU - Suge, Toshiyuki. AU - Kawasaki, Akiko. AU - Ishikawa, Kunio. AU - Matsuo, Takashi. AU - Ebisu, Shigeyuki. PY - 2006/8. Y1 - 2006/8. N2 - Purpose: To evaluate the occluding ability of ammonium hexafluorosilicate (SiF). Methods: Dentin disks prepared from human extracted teeth were grouped as follows to prepare different situations of dentin hypersensitivity: (1) those sonicated for 20 minutes; (2) those treated with 0.5 mol/L EDTA for 2 minutes; (3) those treated with 6% citric acid for 2 minutes; (4) those treated with 50% citric acid for 2 minutes. Then, SiF or diamine silver fluoride (AgF) was applied to the dentin disks and the dentin tubule occlusion was observed with scanning electron microscopy (SEM). The percent of open tubules before and after SiF or AgF treatment were measured by NIH image using SEM photographs. Also, the dentin permeability was measured. ...
TY - JOUR. T1 - Microtensile bond strength between glass ionomer cement and silver diamine fluoride-treated carious primary dentin. AU - Puwanawiroj, Aksrapak. AU - Trairatvorakul, Chutima. AU - Dasanayake, Ananda P.. AU - Auychai, Prim. PY - 2018/7/1. Y1 - 2018/7/1. N2 - Purpose: The study objectives were to investigate the effect of silver diamine fluoride (SDF) on the microtensile bond strength between glass ionomer cement and carious primary dentin and evaluate the mode of restoration failure. Methods: Forty carious primary molars were sectioned in half through the middle of the carious lesion and randomly allocated to test and control groups. The test specimens were treated with 38 percent SDF, and the control, deionized water. The samples were stored in artificial saliva for 14 days at 37 degrees Celsius, and the dentin surfaces were conditioned and restored with Fuji IX GP Extra. After 24 hours in artificial saliva, the specimens were prepared for microtensile bond strength testing and ...
At-home treatments include desensitizing toothpastes or dentifrices, potassium salts, mouthwashes and chewing gums. A variety of toothpastes are marketed for dentin hypersensitivity, including compounds such as strontium chloride, strontium acetate, arginine, calcium carbonate, hydroxyapatite and calcium sodium phosphosilicate.[1] Desensitizing chewing gums[19] and mouthwashes are also marketed.[5] Potassium-containing toothpastes are common; however, the mechanism by which they may reduce hypersensitivity is unclear. Animal research has demonstrated that potassium ions placed in deep dentin cavities cause nerve depolarization and prevent re-polarization. It is not known if this effect would occur with the twice-daily, transient and small increase in potassium ions in saliva that brushing with potassium-containing toothpaste creates. In individuals with dentin hypersensitivity associated with exposed root surfaces, brushing twice daily with toothpaste containing 5% potassium nitrate for six to ...
The aim of this study is to investigate the morphological and chemical changes of demineralized dentin collagen-matrix and resin/dentin interface associated with chitosan/riboflavin modification. Dentin disc specimens were prepared from sound molars, acid-etched with 35% phosphoric acid and modified with either 0.1% riboflavin or chitosan/riboflavin (Ch/RF ratios 1:4 or 1:1) and photo-activated by UVA. Morphological and chemical changes associated with surface modification were characterized by SEM and micro-Raman spectroscopy. Dentin surfaces of sound molars were exposed, acid-etched, and modified as described before. Etch-and-rinse dentin adhesive was applied, light-cured, and layered with resin-restorative composite. The resin infiltration and resin/dentin interface were characterized by micro-Raman spectroscopy and SEM. An open-intact collagen network-structure, formation of uniform hybrid-layer and higher resin infiltration were found with 0.1%RF and Ch/RF 1:4 modifications. Raman analysis ...
TY - JOUR. T1 - The Ability of a Potassium Oxalate Gel Strip to Occlude Human Dentine Tubules; A Novel in vitro. T2 - in situ Study. AU - Chapman, Nicholas. AU - Jones, Siân Bodfel. AU - Bahal, Priya. AU - He, Tao. AU - Drake, Phil. AU - Zou, Yuanshu. AU - West, Nicola X. PY - 2020/9/1. Y1 - 2020/9/1. N2 - Abstract Objectives: To determine if an oxalate strip reduced fluid flow in dentine samples and whether this reduction was maintained following a 14 day intra-oral period. Methods: Dentine tubule fluid flow was measured by a modified Pashley cell in 40 acid-etched dentine discs 1mm thick, diameter ,10mm, with an acquired pellicle, pre-equilibrated with Hartmanns solution and conditioned by toothbrushing, pre and post treatment (10min) with an oxalate (3.14%) gel strip or no treatment. One control and one test sample were exposed in-situ for 14 days to the oral environment in 20 healthy adult volunteers, and fluid flow re-measured. The appliance containing the two samples was removed for ...
The aim of this study was to evaluate the microtensile bond strength of two all-in-one self-etch adhesives applied to sound and caries-affected dentin with four different application techniques. Forty extracted third molars with occlusal caries were randomly divided into four groups for G-Aenial Bond and S3 Bond: (1) according to manufacturer-s instructions; (2) with acid etching before applying adhesives; (3) doubling adhesive application time; and (4) doubling adhesive coating. Teeth were sectioned to obtain 1-mm-+/- 0.2-mm-thick dentin sticks and subjected to a tensile force. For G-Aenial Bond, doubling the time and application of two consecutive coats produced significantly higher strength than that obtained by following manufacturers- instructions and acid etching application to sound dentin. Prior acid etching and application of two consecutive coats to caries-affected dentin generated significantly higher bond strength than that using other techniques. For S3 Bond, there was no ...
The aim of this study was to evaluate the regional push-out bond strengths for two fiber-reinforced post types using three different dentin bonding agents Sixty single-rooted extracted human first premolar teeth were sectioned below the cemento-enamel junction, and the roots were endodontically treated Following standardized post space preparations, the roots were divided into two fiber-post groups (Glassix (R) and Carbopost (R)), and further divided into three subgroups of 10 specimens each for the bonding systems self-etching dentin bonding agents (Clearfil (TM) SE Bond and Optibond (R) all-in-one), and total-etching dentin bonding agent (XP Bond (TM)) A dual-cure resin luting cement (Maxcem (TM)) was then placed in the post spaces and posts were then seated into the root canals polymerized through the cervical portion The roots were then cut into 3-mm thick sections Push-out tests were performed at a crosshead speed of 0 5 mm/min. The data were analyzed with multivariate ANOVA (alpha = 0 05) ...
This study evaluated the MMP inhibition of the zinc oxide and copper nanoparticles (ZnO/CuNp), and the effects of their addition into adhesives on antimicrobial activity (AMA), ultimate tensile strength (UTS), in vitro degree of conversion (in vitro-DC), as well as, resin-dentin bond strength (μTBS), nanoleakage (NL) and in situ-DC on caries-affected dentin. Anti-MMP activity was evaluated for several MMPs. ZnO/CuNp (0% [control]; 5/0.1 and 5/0.2 wt%) were added into Prime&Bond Active (PBA) and Ambar Universal (AMB). The AMA was evaluated against Streptococcus mutans. UTS were tested after 24 h and 28d. After induced caries, adhesives and composite were applied to flat dentin surfaces, and specimens were sectioned to obtain resin-dentin sticks. μTBS, NL, in vitro-DC and in situ-DC were evaluated after 24 h. ANOVA and Tukeys test were applied (α = 0.05). ZnO/CuNp demonstrated anti-MMP activity (p < 0.05). The addition of ZnO/CuNp increased AMA and UTS (AMB; p < 0.05). UTS for PBA, in ...
This study aimed to characterize fluoride-induced alterations in dentin mineralization within a dentin-pulp organ culture system. Tooth sections derived from male Wistar rat incisors were cultured in Trowel-type culture for 14 days, in the presence of 0 mM, 1 mM, 3 mM and 6 mM sodium fluoride. Tooth sections were processed and analyzed for uptake of fluoride, its subsequent effect on dentin mineralization by tetracycline hydrochloride incorporation and mineral composition, expressed as calcium/phosphorous (Ca/P) ratios. Tetracycline hydrochloride incorporation was demonstrated to decrease with increased fluoride exposure, accompanied by significant increases in both Ca/P ratios and fluoride incorporation. These findings provide further evidence that the established alterations in dentin formation during fluorosis are a consequence of disruption to the mineralization process, and provide a model system with which to investigate further the potential role the extracellular matrix plays in inducing ...
High-temperature materials in service experience mechanical damage due to operating load and metallurgical damage due to operating temperature. When designing or assessing life of high-temperature components, must consider both factors. In this paper, the effect of tensile hold time on high-temperature fatigue crack growth and long-term prior thermal aging heat treatment on creep rupture behavior were investigated by using STS 316L and STS 316, austenitic stainless steels, which are widely used for automotive exhaust and piping of high-temperature component. STS 316L steel was tested for fatigue crack propagation test by applying 0 sec., 5 sec., 10 sec., 50 sec., and 100 sec. tensile hold times in trapezoidal waveform at 600°... and by using the prior aged STS 316, creep rupture tests were conducted under various stress conditions and at various temperatures. In high-temperature fatigue crack growth tests using STS 316L, as tensile hold time increased crack growth rate (da/dN) decreased in ...
Looking for online definition of irregular dentin in the Medical Dictionary? irregular dentin explanation free. What is irregular dentin? Meaning of irregular dentin medical term. What does irregular dentin mean?
0168]Continuous intrafibrillar and interfibrillar remineralization that occurred after 4 weeks are illustrated in FIG. 6. It was difficult to distinguish the remineralized dentin matrix from the underlying intact mineralized dentin using FESEM, except for the absence of peritubular dentin around the orifices of the dentinal tubules (FIG. 6A). FESEM analysis indicated that the remineralized dentin attained enough support to prevent it from collapse or shrinkage during high vacuum SEM examination. Peritubular dentin (open arrow) was absent from the superficial 5 μm of the dentinal tubules. At higher magnification, it was apparent that the majority of the collagen fibrils exhibited the corn-on-the-cob appearance (arrow), representative of interfibrillar mineralization, while other smaller diameter fibrils were devoid of interfibrillar minerals and exhibited only faint banding characteristics (open arrowhead) (FIG. 6B). Low magnification TEM showed that the partially remineralized dentin (open ...
Methodology Single-rooted human premolars were irrigated as follows (n = 12 per group): (1) 1% NaOCl during instrumentation, deionized water after instrumentation, (2) 1% NaOCl during, 17% EDTA after instrumentation, (3) a 1 : 1-mixture of 2% NaOCl and 18% EA during and after instrumentation, and (4) 1% NaOCl during, 2.25% PA after instrumentation. Irrigant volumes and contact times were 10 mL/15 min during and 5 mL/3 min after instrumentation. The evaluated outcomes were eluted calcium by atomic absorption spectroscopy, smear-covered areas by scanning electron microscopy in secondary electron mode and apparent canal wall decalcifications on root transsections in backscatter mode. For the smear layer analysis, sclerotic dentine was taken into consideration. Results were compared using appropriate parametric and nonparametric tests, alpha = 0.05 ...
MTA와 dentin 사이의 계면 결합력을 평가하기 위해 dentin 시편에 MTA를 충전시킨 후 전단강도를 측정하였으며 7개의 단근치와 5개의 다근치의 root 부위를 실험에 이용하였다. 지름 10mm의 플라스틱 mold에 치아 root를 2mm 길이로 절단하여 매몰하고 이를 직경 1.3mm의 diamond bur로 dentin의 canal을 따라 2mm의 depth로 삭제하였다. 원기둥형으로 치아삭제를 하여 20개의 시편을 제작하였고 이 중에서 실험에 적합한 18개의 시편을 선택하였다. 총 24개의 canal에 MTA(ProRoot MTA, Dentsply, Tulsadental, Tulsa, OK, USA)를 증류수, 1.0%, 2.0% chlorhexidine의 3개의 group으로 분류하여 충전하였다. LF-Plus digital testing machine (Lloyd instrument, Ametek)을 이용하여 1mm/min의 속도로 시편에 dislodgement force를 가하였고 MTA부분이 dentin으로부터 분리될 때의 load를 측정했다. SPSS ver. 19.0K를 이용했고, 유의수준(p-value) 0.05를 ...
TY - JOUR. T1 - Identification of the chondrogenic-inducing activity from bovine dentin (bCIA) as a low-molecular-mass amelogenin polypeptide. AU - Nebgen, D. R.. AU - Inoue, H.. AU - Sabsay, B.. AU - Wei, K.. AU - Ho, C. S.. AU - Veis, A.. PY - 1999. Y1 - 1999. N2 - Dentin extracellular matrix has been shown to contain components capable of inducing chondrogenesis and osteogenesis at ectopic sites when implanted in vivo, and chondrogenesis in cultures of embryonic muscle-derived fibroblasts (EMF) in vitro. The polypeptide responsible, called the chondrogenic-inducing agent (CIA), has been isolated from a 4.0-M guanidinium hydrochloride extract of demineralized bovine dentin matrix. Following Sephacryl S-100 chromatography, CIA activity was identified in fractions by assay for uptake of [35S]-SO4 into proteoglycan by the EMF after 24 hrs in culture. The active fraction induced the EMF to produce type II collagen mRNA and decrease production of type I collagen mRNA after 5 days in culture. The ...
Host-derived proteases have been reported to degrade the collagen matrix of incompletely-resinin-filtrated dentin. This study tested the hypothesis that interfacial degradation of resin-dentin bonds may be prevented or delayed by the application of chlorhexidine (CHX), a matrix metalloproteinase inhibitor, to dentin after phosphoric acid-etching. Contralateral pairs of resin-bonded Class I restorations in non-carious third molars were kept under intra-oral function for 14 months. Preservation of resin-dentin bonds was assessed by microtensile bond strength tests and TEM examination. In vivo bond strength remained stable in the CHX-treated specimens, while bond strength decreased significantly in control teeth. Resin-infiltrated dentin in CHX-treated specimens exhibited normal structural integrity of the collagen network. Conversely, progressive disintegration of the fibrillar network was identified in control specimens. Auto-degradation of collagen matrices can occur in resin-infiltrated dentin, ...
Dentinogenesis imperfecta (DI) type II, an inherited disorder affecting dentin, has been linked to mutations in the dentin sialophosphoprotein ( DSPP) gene on chromosome 4q21. The gene product is cleaved into two dentin-specific matrix proteins, dentin sialoprotein (DSP) and dentin phosphoprotein. The aim of this investigation was to study genotypes and phenotypes in two affected families with special reference to clinical, radiographic, and histopathologic manifestations. Seven affected members of Family A and five of Family B were documented clinically and radiographically; 14 and 10 teeth, respectively, were available for histopathologic investigation and prepared for ground sections, which were assessed semiquantitatively for dysplastic manifestations in the dentin according to the scoring system, dysplastic dentin score (DDS). Venous blood samples were collected from six affected and ten unaffected members of Family A, and from eight affected and six unaffected members of Family B. Genomic ...
ABSTRACT. Aim: To evaluate the comparative efficacy of Polymer bur (Smartprep) and Conventional burs (Carbide bur & Diamond Points) in selective Dentin caries removal. Materials and method: 15 freshly extracted carious human premolars and molars were selected for this study. These teeth were split in the center of carious lesion, in order to obtain two corresponding half. Thus 30 samples were prepared in this way. These were randomly divided in to 3 groups of 10 samples each. Group 1: The carious portion of these samples was excavated with the help of polymer bur Smartprep (SS White). Group 3: Prepared with Tungsten carbide round bur (No. 018). Group 3: Prepared with the help of Diamond points (No. 018). The period of time involved in this process is measured. After excavation of all carious lesions, a longitudinal section from mid most part of lesion was obtain with the help of diamond disc at slow speed. After staining with caries detector dye Seek, the sections were subjected to ...
Dentin matrix protein 1 (DMP1) is an acidic extracellular matrix phosphoprotein that can bind calcium. DMP1 is required for bone and dentin mineralization and is expressed in the cells of bone and teeth. It is thought to play a role in regulating expression of osteoblast-specific genes during osteoblast cell differentiation and is localized to the nucleus in osteoblast precursor cells. In mature osteoblasts, the DMP1 protein is phosphorylated and localized to the extracellular matrix, where it plays a role in forming mineralized matrix. While other constitutively expressed proteins in the extracellular matrix, such as osteopontin and osteocalcin, are expressed in osteoblast cells, DMP1 is expressed in osteocytes, making it a candidate biomarker for osteocyte activity.. ...
Dentin matrix protein 1 (DMP1) is an acidic extracellular matrix phosphoprotein that can bind calcium. DMP1 is required for bone and dentin mineralization and is expressed in the cells of bone and teeth. It is thought to play a role in regulating expression of osteoblast-specific genes during osteoblast cell differentiation and is localized to the nucleus in osteoblast precursor cells. In mature osteoblasts, the DMP1 protein is phosphorylated and localized to the extracellular matrix, where it plays a role in forming mineralized matrix. While other constitutively expressed proteins in the extracellular matrix, such as osteopontin and osteocalcin, are expressed in osteoblast cells, DMP1 is expressed in osteocytes, making it a candidate biomarker for osteocyte activity.. ...
Dentin Sensitivity; Dentin Hypersensitivity. On-line free medical diagnosis assistant. Ranked list of possible diseases from either several symptoms or a full patient history. A similarity measure between symptoms and diseases is provided.
BackgroundLight curing of resin composite is associated with a thermal rise that may have harmful effect on the health of the vital pulp. In addition, desirable polymerization is important to achieve mechanical properties and clinical function. The purpose of this in‑vitro study was to compare the thermal rise under normal dentin during photopolymerization and degree of conversion (DC) of bulk fill and conventional resin composite using continuous high‑ and soft‑start mode.Materials and MethodsIn this in‑vitro study, Cl I cavities with a dimension of 4 mm × 4 mm × 4 mm and remaining dentin thickness of 1 mm were prepared on 56 extracted human molars. The temperature rise during the light curing of conventional resin composite (Tetric N Ceram, Ivoclar Vivadent) by incremental filling technique and bulk‑fill resin composite (Tetric N Ceram Bulk Fill, Ivoclar Vivadent) by bulk‑filling technique were measured with a K‑type thermocouple wire. DC of both resin composites was measured
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The aim of the present study was to evaluate the influence different bleaching agents and concentrations on microtensile bond strength of different dentin adhesives in class V cavities. 135 freshly extracted third molars were included in this study. In all teeth cervical class V dentinal cavities were prepared allowing the simulation of dentin perfusion. The specimens were randomly assigned to nine experimental groups of fifteen each: S0: Syntac/ control; S17: Syntac/ Perfect Bleach 17%; S38: Syntac/ Opalescene Xtra Boost 38%; X0: XP Bond/ control; X17: XP Bond/ Perfect Bleach 17%; X38: XP Bond/ Opalescene Xtra Boost 38%; A0: AdheSE One/ control; A17: AdheSE One/ Perfect Bleach 17%; A38: AdheSE One/ Opalescene Xtra Boost 38%. Bleaching was performed 8 hours at 36°C for 7 days. Between the ranges all samples were stored in physiological saline for 16 hours. The dentin adhesives used as recommended by manufactures instruction were applied on a standardized dentin surface. Microtensile bond ...
Objective: The purpose of this in vitro study was to determine the microtensile bond strengths (µTBS) of 3 dental adhesives when applied to dentin decalcified with ethylenediaminetetraacetic acid (EDTA). The null hypothesis tested was that the removal of calcium from dentin would not influence the bond strengths. Method and materials: Eighteen extracted human molars were cut in 2 equal halves. One half served as the control, having no EDTA treatment, while the other half was assigned to 1 of 3 periods (1 hour, 24 hours, or 100 hours) of decalcificatioin with buffered 0.5 mol/L EDTA. Middle dentin was bonded with 1 of 3 dentin adhesive groups: a self-etching primer, Clearfil SE Bond (SE); an acetone-based total-etch adhesive, Prime&Bond NT (NT); and an ethanol- and water-based total-etch adhesive, Single Bond (SB). The specimens were restored with Z-250 resin composite and sectioned in 0.9 ± 0.2 mm2 sticks that were tested in tensile mode. Results: For each adhesive, the control group (not ...
Fig. (2d) SEM micrograph of the top surface of dentin disc in the BIF-CA Group: The dentin surface was covered with a semi-porous layer (2,000X). ...
Dentin is one of the most durable biological materials in the human body. Researchers from Charité - Universitätsmedizin Berlin were able to show that the reason for this can be traced to its nanostructures and specifically to the interactions between the organic and inorganic components. Measurements performed at BESSYII, the Helmholtz-Zentrum Berlins synchrotron radiation source, showed that it is the mechanical coupling between the collagen protein fibers and mineral nanoparticles which renders dentin capable of withstanding extreme forces. Results from this research have been recently published in the journal Chemistry of Materials*.. In humans, teeth come into contact almost 5,000 times per day under normal use. In spite of this, and although we often use large forces during mastication, it is surprisingly rare for healthy teeth to break. It is widely accepted that the design of teeth makes teeth tough, where an inner core, known as dentin, supports the outer hard enamel cap. The secret ...
TY - JOUR. T1 - Thermo-debonding mechanisms in dentin bonding systems using finite element analysis. AU - Lee, Sheng Yang. AU - Chiang, Hsin Chih. AU - Huang, Haw Ming. AU - Shih, Yung Hsun. AU - Chen, Hsin Chung. AU - Dong, De Rei. AU - Lin, Che Tong. N1 - 被引用次數:24 Export Date: 9 August 2016 CODEN: BIMAD 通訊地址: Lee, S.-Y.; Grad. Inst. Oral Rehabilitation Sci., Taipei Medical College, 250 Wu-Hsing Street, Taipei, Taiwan; 電子郵件: [email protected] 化學物質/CAS: Biocompatible Materials; Dentin-Bonding Agents; Optibond; Resin Cements; Scotchbond Multi-Purpose 商標: Clearfil Protect liner, Kuraray, Japan; Dentin; Hybrid layer; Optibond; Scotchbond MP; Tenure; Z100 製造商: Kuraray, Japan 參考文獻: Van Noort, R., Cardew, G.E., Howard, I.C., A study of the interfacial shear and tensile stresses in a restored molar tooth (1988) J Dent, 16, pp. 286-293; Van Noort, R., Noroozi, S., Howard, I.C., Cardew, G.E., A critique of bond strength measurements (1989) J ...
Tooth sensitivity or known as dentin hypersensitivity is short or transient sharp pain of a rapid onset that arises from exposed dentin layer of one or more teeth subsequent to loss of tooth structure (enamel layer of the crown or cementum layer of the root). It usually occurs in response to stimuli-typically cold, air pressure, drying, sugar, acids, chemicals or forces acting onto the tooth-and cannot be ascribed to any other dental defects or pathology. These stimuli are non-noxious, and are not generally expected to generate a pain response, except as seen in sensitive teeth. In contrast, a noxious stimulus would be the toxins of bacteria within a decay lesion leading to dentinal pain. Areas of exposed dentin at the junction between the crown and the root (cervical area) account for much of the observed tooth sensitivity. Continue reading →. ...
Inaugural-Dissertation (Dr. med. dent.). Marginale Adaptation & Verschleissfestigkeit experimenteller CEREC - Porzellaninlays in vitro (Arbeit unter der Leitung von PD Dr. med. dent. I. Krejci).. Publikationsübersicht. Marending M, Lutz F, Barbakow F. Scanning electron microscope appearances of Lightspeed instruments used clinically: a pilot study. International Endodontic Journal (1998) 31, 57-62.. Marending M, Peters OA, Zehnder M. Factors affecting the outcome of orthograde root canal therapy in a general dentistry hospital practice. Oral Surg Oral Med Oral Pathol Oral Radiol Endod (2005) 99, 119-24.. Marending M, Brunner T, Luder H, Stark WJ, Zehnder M. Effect of sodium hypochlorite on human root dentine - mechanical, chemical and morphological evaluation. International Endodontic Journal (2007) 40, 786-793.. Marending M, Paqué F, Fischer J, Zehnder M. Impact of irrigant sequence on mechanical properties of human root dentin. Journal of Endodontics (2007) 33, 1325-1328.. Marending M, ...
Objectives Contemporary methods of dentin bonding could create hybrid layers (HLs) containing voids and exposed demineralized collagen fibers. and without 5% PA were bonded to the acid etched dentin. Five-μm-thick sections cut from the bonded specimens were stained with Goldners trichrome. The specimens were then exposed to 0.1% collagenase solution for zero one or six days. Following collagenase treatment the specimens were analyzed with SEM/TEM. Results Staining did not SB-220453 reveal a difference in the HLs created with the two adhesives. SEM showed the presence of intact collagen fibrils in all collagenase treatment conditions for specimens bonded with adhesive containing PA. These integral collagen fibrils were not observed in the specimens bonded with adhesive without PA after the same collagenase treatment. TEM confirmed that the specimens containing PA still showed normal collagen fibril organization and dimensions after treatment with collagenase solution. In contrast disorganized ...