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Indian Journal of Dermatology,... 2015Dental restorative materials containing silver-mercury compounds have been known to induce oral lichenoid lesions.
BACKGROUND
Dental restorative materials containing silver-mercury compounds have been known to induce oral lichenoid lesions.
OBJECTIVES
To determine the frequency of contact allergy to dental restoration materials in patients with oral lichenoid lesions and to study the effect of removal of the materials on the lesions.
RESULTS
Forty-five patients were recruited in three groups of 15 each: Group A (lesions in close contact with dental materials), Group B (lesions extending 1 cm beyond the area of contact) and Group C (no topographic relationship). Thirty controls were recruited in two groups of 15 individuals each: Group D (oral lichenoid lesions but no dental material) and Group E (dental material but no oral lichenoid lesions). Patch tests were positive in 20 (44.5%) patients. Mercury was the most common allergen to elicit a positive reaction in eight patients, followed by nickel (7), palladium (5), potassium dichromate (3), balsam of Peru, gold sodium thiosulphate 2 and tinuvin (2) and eugenol (1), cobalt chloride (1) and carvone (1). Seven patients elicited positive response to more than one allergen. In 13 of 20 patients who consented to removal of the dental material, complete healing was observed in 6 (30%), marked improvement in 7 (35%) and no improvement in 7 (35%) patients. Relief of symptoms was usually observed 3 months after removal.
LIMITATIONS
Limited number of study subjects and short follow up after removal/replacement of dental restoration materials are the main limitations of this study.
CONCLUSION
Contact allergy to amalgam is an important etiologic factor in oral lichenoid lesions and removal of restorative material should be offered to patients who have lesions in close proximity to the dental material.
Topics: Adult; Aged; Dental Materials; Dermatitis, Allergic Contact; Female; Humans; Lichenoid Eruptions; Male; Middle Aged; Mouth Mucosa; Patch Tests; Prospective Studies
PubMed: 26261149
DOI: 10.4103/0378-6323.162341 -
The Journal of Adhesive Dentistry 2020The aim of this review article was to provide an overview of the scientific and patent literature on the different synthesis pathways of modified polyacids suitable for... (Review)
Review
PURPOSE
The aim of this review article was to provide an overview of the scientific and patent literature on the different synthesis pathways of modified polyacids suitable for application in a new class of restorative dental materials.
METHODS
The literature based on patents and publications from 2009 to 2018 of Dentsply Sirona in cooperation with Heinrich Heine University, Düsseldorf, was reviewed and summarized.
RESULTS
Multiple approaches towards the development of polymerizable acid polymers have been introduced and their strength and weaknesses were discussed. A target structure and the respective synthesis were developed allowing the formulation of a restorative dental material with unique properties, such as high mechanical strength paired with good adhesion properties.
CONCLUSION
From a variety of hydrolytically stable acidic polymers, the most promising versions were selected and used for the product development of Surefil one (Dentsply Sirona).
Topics: Composite Resins; Dental Materials; Materials Testing; Polymers; Surface Properties
PubMed: 32030374
DOI: 10.3290/j.jad.a43995 -
Clinical Materials 1994Biocompatibility has been described as the ability of a material to perform with an appropriate host response in a specific application. Appropriate host response means... (Review)
Review
Biocompatibility has been described as the ability of a material to perform with an appropriate host response in a specific application. Appropriate host response means no (or a tolerable) adverse reaction of a living system to the presence of such a material. An adverse reaction may be due to the toxicity of a dental material. Therefore toxicity may be regarded as one reason for nonbiocompatibility of a dental material. The toxicity of a dental material can be evaluated by in vitro tests, animal experiments and clinical trials. There exists a variety of different in vitro test methods. The most widely used biological systems for toxicity screening of dental materials are cell cultures. Cell cultures for toxicity screening of dental materials are valuable tools for understanding their biological behavior, if the limitations of the methods are taken into consideration, especially concerning the interpretation of the results. Further research should concentrate on better simulations of the in vivo situation in cell cultures. In this review the applications of various cell culture methods to evaluate the cytotoxicity of a wide range of dental materials, e.g. metals, alloys, polymers and cements, are described.
Topics: Animals; Biocompatible Materials; Biological Assay; Cells, Cultured; Dental Materials; Evaluation Studies as Topic; Humans; Materials Testing; Research Design
PubMed: 10147390
DOI: 10.1016/0267-6605(94)90088-4 -
Clinical Oral Investigations May 2020To evaluate the artifact expression of a new material-polylactic acid (PLA)/hydroxyapatite (HA)/graphene oxide (GO) nanocomposite-and compare it with that of commonly...
OBJECTIVE
To evaluate the artifact expression of a new material-polylactic acid (PLA)/hydroxyapatite (HA)/graphene oxide (GO) nanocomposite-and compare it with that of commonly used dental materials, using cone-beam computed tomography.
MATERIALS AND METHODS
Cylinders of amalgam alloy, metal alloy, titanium, gutta-percha, and PLA/HA/GO were individually placed in the center of an acrylic phantom. Three images of each phantom + cylinder set were acquired using a Picasso Trio unit (Vatech, Hwaseong, South Korea) set at 90 kVp, 3.7 mA, 0.2 mm voxel size, and 12 × 8.5 cm FOV. Three images of a control group (sound phantom) were also obtained. Eight ROIs were established in each image to evaluate the standard deviation (S.D.) of gray values in the ImageJ Software. The Kruskal-Wallis test with the Student-Newman-Keuls post hoc was employed, considering a significance level of 5%.
RESULTS
There were no significant differences in S.D. between the control and PLA/HA/GO images (p = 0.712). Both control and PLA/HA/GO showed fewer image artifacts than the other materials (p < 0.05). The images of the amalgam alloy did not differ from the metal alloy images (p = 0.691), showing more artifacts than the gutta-percha (p = 0.028) and titanium (p = 0.051).
CONCLUSIONS
The PLA/HA/GO produced fewer artifacts and a better-quality image than the other tested materials.
CLINICAL RELEVANCE
The PLA/HA/GO has physical and biological properties similar to those of dental materials. Since it has produced fewer image artifacts, this new nanocomposite may be employed in the near future, enhancing the diagnosis in CBCT.
Topics: Artifacts; Cone-Beam Computed Tomography; Dental Materials; Durapatite; Graphite; Nanocomposites; Phantoms, Imaging; Polyesters
PubMed: 31338631
DOI: 10.1007/s00784-019-03027-3 -
The Journal of Prosthetic Dentistry May 2024The increasing use of computer-aided design and computer-aided manufacturing (CAD-CAM) systems has led to the development of resin-ceramic materials that meet the... (Review)
Review
STATEMENT OF PROBLEM
The increasing use of computer-aided design and computer-aided manufacturing (CAD-CAM) systems has led to the development of resin-ceramic materials that meet the requirements of minimally invasive dentistry, including the resin nanoceramic (RNC) and polymer-infiltrated ceramic network (PICN). The wear characteristics of these materials are unclear.
PURPOSE
The purpose of this systematic review was to compare the wear resistance of resin-ceramic materials when compared with one another or with lithium disilicate glass-ceramics.
MATERIAL AND METHODS
The PubMed, Scopus, and DOSS search engines were used to identify articles published between 2013 and 2021. Two independent researchers conducted the systematic review by following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and by following a combination of keywords.
RESULTS
Of a total of 310 articles, 26 were selected, including only 1 clinical study. Among these, 15 compared resin-ceramic materials with each other, while 11 compared resin-ceramic materials with lithium disilicate ceramics. Two types of wear were used to compare the materials: attrition and abrasion. The most commonly studied materials were 2 RNCs (Lava Ultimate and Cerasmart), 1 PICN (Vita Enamic), and 1 ceramic (IPS e.max CAD). Among the resin-ceramic materials, the PICN (Vita Enamic) showed less wear than the RNCs. Of the RNCs, Cerasmart had less attrition wear and less wear of the opposing teeth.
CONCLUSIONS
Lithium disilicate glass-ceramics have a higher wear resistance than resin-ceramic materials, but they cause more wear of the opposing teeth.
Topics: Computer-Aided Design; Ceramics; Humans; Dental Porcelain; Dental Restoration Wear; Dental Materials; Resins, Synthetic
PubMed: 35459543
DOI: 10.1016/j.prosdent.2022.01.027 -
Acta of Bioengineering and Biomechanics 2015The aim of this study was to investigate wear and friction behaviour of tooth enamel against selected dental restorative materials.
PURPOSE
The aim of this study was to investigate wear and friction behaviour of tooth enamel against selected dental restorative materials.
METHODS
The experimental material was obtained under simulated mastication, during which human tooth enamel was sub- jected to friction and wear in contact with composite dental materials: Estelite Sigma and FulFil Extra.
RESULTS
The results have shown that the enamel's resistance to tribological wear is significantly higher than the resistance of the dental materials tested. The microscopic observations of the sample surfaces subsequent to the tribological research as well as the analysis of the chemical composition of the surface layer confirm the existence of diverse tribological wear mechanisms dependent on the type of dental materials used.
CONCLUSIONS
Composite materials such as Estellite Sigma and FulFil Extra are characterized by greater resistance to wear and are less destructive to enamel than the material investigated by the authors earlier. It has also been stated that the spherical shape of the filler particles (Estellite Sigma) has a beneficial effect in reducing enamel wear.
Topics: Ceramics; Composite Resins; Dental Enamel; Dental Materials; Dental Porcelain; Dental Restoration Wear; Equipment Design; Friction; Hardness; Humans; Materials Testing; Microscopy, Electron, Scanning; Surface Properties
PubMed: 25952294
DOI: No ID Found -
Der Hautarzt; Zeitschrift Fur... Nov 1996The problems in patch testing and relevance evaluation as well as the practical consequences are discussed for the most important groups of dental materials (DM). These... (Review)
Review
The problems in patch testing and relevance evaluation as well as the practical consequences are discussed for the most important groups of dental materials (DM). These include metal alloys: amalgam with a low allergy prevalence; palladium salts showing a high correlation with nickel allergy but a low one with metallic palladium or alloys; the widespread allergen nickel is most relevant when dealing with nickel containing DM-alloys that are not corrosionresistant; gold salts with widely differing test results and limited benefit to detect genuine gold intolerance. Among synthetic resins methylmethacrylate is the most important allergen because of the high frequency of exposition. With composite materials and other methacrylates, both cross reactions and active sensitization should be kept in mind. Relevant reactions due to additives are rare; positive benzoylperoxide tests should be interpreted very critically. A number of DM may contain allergens of the etheric oils-colophonium - Perubalsam group. DM should be tested with standardized methods only. As the dental consequences may be expensive, interpretation of such test results demands utmost care and special experience.
Topics: Adult; Composite Resins; Dental Alloys; Dental Amalgam; Dental Materials; Female; Humans; Hypersensitivity; Male; Middle Aged; Mouth Mucosa; Patch Tests; Stomatitis
PubMed: 9036138
DOI: 10.1007/s001050050518 -
Operative Dentistry 2008The setting of dental composites is accompanied by significant polymerization contraction, resulting in the generation of stresses within the material and at the... (Review)
Review
The setting of dental composites is accompanied by significant polymerization contraction, resulting in the generation of stresses within the material and at the tooth-restoration interface. These stresses can have a deleterious effect on marginal integrity if they exceed the adhesive strength of the restorative, as well as on the properties of the composite. It has been determined that several factors affect these stresses, including the polymerization rate of the composite, its formulation, including filler and monomer composition and the constraints imposed by the geometry of the cavity preparation. Many strategies have been developed to reduce the effect of these stresses. Changes in the formulation of the composite have included experimentation with a variety of stress relieving additives, modified catalyst compositions and alternative monomer systems. Modifications to the placement techniques have included the use of incremental curing, altered light activation schemes and resilient liners. This manuscript will review many of the important scientific and clinical issues relating to the generation and quantitation of the stresses produced in dental composites during curing.
Topics: Chemistry, Pharmaceutical; Composite Resins; Dental Cavity Lining; Dental Materials; Dental Restoration, Permanent; Humans; Light; Polymers; Stress, Mechanical
PubMed: 18505214
DOI: 10.2341/07-BL2 -
Journal of Oral Rehabilitation Dec 2007At the outset, the categories of physical, chemical, mechanical, biological and clinical properties of biomaterials are reviewed in terms of their definitions and... (Review)
Review
At the outset, the categories of physical, chemical, mechanical, biological and clinical properties of biomaterials are reviewed in terms of their definitions and relevant examples. Clinical performance for restorative materials is considered in terms of five crucial categories of factors (operator, design, materials, site and patient). Clinical performance assessment in actual clinical trials is described in terms of United States Public Health Service (USPHS) and modified USPHS categories of ratings collected from direct observations. Clinical failure analysis is characterized using reverse s-shaped curves to summarize longevity (failure or success) and clinical longevity for 50% failures (CL(50)) is defined. Actual practice effectiveness is demonstrated as being approximately one-half of clinical trial efficacy. Types of restorative dental material clinical trials are contrasted (longitudinal versus cross-sectional, short-term versus long-term, university-based versus practice-based research networks). Poor correlations between laboratory test values and clinical performance are explained. The need for risk assessment is emphasized. Evidence-based dentistry is defined in terms of available published information and precautions. At this point, the evidence base for clinical performance of biomaterials is scant.
Topics: Biocompatible Materials; Decision Making; Dental Materials; Dental Restoration Failure; Dental Restoration, Permanent; Humans; Materials Testing; Randomized Controlled Trials as Topic; Risk Assessment; United States
PubMed: 18034674
DOI: 10.1111/j.1365-2842.2007.01812.x -
Clinical Materials 1991The origin of the glass-ionomer cement lies in a change in attitude regarding the qualities demanded of a dental material. The foundation of dental materials science in... (Review)
Review
The origin of the glass-ionomer cement lies in a change in attitude regarding the qualities demanded of a dental material. The foundation of dental materials science in the 1920s tended to stultify the development of dental materials because of an over emphasis on mechanical properties. In this period, traditional materials invented before the end of the 19th century remained in use. A change in approach in the 1950s and 1960s, brought about by the realization of the importance of biocompatibility and adhesion, led to a revolution in dental materials science. This era was characterized by closer collaboration between materials research scientist and clinician. New materials were developed, including the glass-ionomer cement, with novel properties which were exploited by the development of novel clinical techniques. The glass-ionomer cement has the crucial property of adhering to untreated dentine and enamel, a quality which has led to the development of clinical techniques to minimize cavity preparation and thus loss of tooth material.
Topics: Dental Bonding; Dental Materials; Forecasting; Glass Ionomer Cements; History, 20th Century; Humans; Materials Testing; Research
PubMed: 10149142
DOI: 10.1016/0267-6605(91)90070-v