Components Of Dental Materials Research Articles

Ytterbium (III) Fluoride in Dental Materials

(1) Background: The compound ytterbium trifluoride is used as a component of several dental materials, and this is reviewed in the current article. (2) Methods: Published articles on this substance were identified initially from PubMed, and then from Science Direct and Google Scholar. The publications identified in this way showed that ytterbium trifluoride has been included in a variety of dental restorative materials, including composite resins, glass polyalkenoate cements, and calcium trisilicate cements. (3) Results: Ytterbium trifluoride is reported to be insoluble in water. Despite this, its presence is associated with fluoride release from dental materials. There is evidence that it reacts with the components of calcium trisilicate cements to form small amounts of a variety of compounds, including ytterbium oxide, Yb2O3, and calcium–ytterbium fluoride, CaYbF5. In nanoparticulate form, it has been shown to reinforce glass polyalkenoates and it also provides high contrast in X-ray images. (4) Conclusions: Ytterbium trifluoride is a useful component of dental materials, though some of the published findings suggest that there are aspects of its chemistry which are poorly understood.

Minimal Intervention Dentistry: Biocompatibility and Mechanism of Action of Products for Chemical-Mechanical Removal of Carious Tissue

Conventional method for removal of carious tissue using low speed drills usually induce noise and vibration, in addition to thermal and pressure effects that can be harmful to the pulp tissue and cause fear in children. Therefore, several alternative methods are being developed to try to minimize the unpleasant perception of the patient during caries removal. Chemical-mechanical removal of carious tissue goal is to selectively remove the carious lesion, which reduces the amount of bacteria inside the cavity without removing the tissue susceptible to remineralization. This method is also able to minimize the tactile perception by the patient during the manipulation of the lesion compared to the conventional method, and, therefore, it has been widely accepted among phobic patients, children and special needs patients. Due to the close relationship between dentin and pulp tissue, all injuries imposed on this dentin may have repercussions on the underlying pulp connective tissue. The morphological aspects of remaining dentin favor the diffusion of chemical components of dental materials, which can be toxic to the pulp tissue or even negatively interfere in the reparative process. Thus, considering the proximity between the applied material and the underlying pulp tissue, especially in deep cavities, there is a need to assess the biological behavior of dental materials against pulp cells, since aggressions to the pulp tissue can be caused not only by metabolites from microorganisms involved in dental caries but also by components that are released from these products. This subject was explored in this narrative literature review.

Allergic reactions to the components of dental materials and the possibilities of their diagnostics

Allergic reactions to the components of dental materials and the possibilities of their diagnostics

Biocompatibility as an Important Component of Dental Materials

Decades ago, implants appeared that were used to restore lost teeth. Improvement work continues to this day. Specialists are interested in increase in the reliability and strength, as well as in the high quality of fusion of implants with living tissue. The article studies scientific approaches to the creation of biocompatible dental materials, considers their types, defines the basic requirements for biocompatible dental materials.

Allocation of a tryptase in stomatic liquid and activation of basophiles at an intolerance of stomatologic materials

The goal of the study was to determine the levels of mast cell tryptase (MCT) in whole saliva and IgE antibodies in blood in patients with intolerance to dental prosthetic materials (intolerance to dental materials – IDM) before and after removal of prosthetic constructions. We have conducted an examination of the patients suffering from the symptoms of IDM, who were divided into 2 groups depending on the time span between the end of prosthetic treatment and the emergence of pathological symptoms: group 1 (n=19) – from 1 to 14 days (emergence of symptoms took place immediately after treatment); group 2 – (n=18) – from 6 months to 5 years, group 3 (n=16) – controls – no complaints of IDM. Whole saliva (WS) samples were collected before removal of prosthetic constructions and 1 month after. In group 1 patients we could detect salivary MCT in 16 (84,2%) subjects before removal of prosthetic constructions, and 1 month after MCT in whole saliva was not found (p<0,001). MCT in whole saliva of control group patients was not detected both before and after removal of prosthetic constructions. Thus, mast cell tryptase in whole saliva is a diagnostic marker for intolerance to dental materials. In group 1 patients we detected IgE antibodies to Ni-HSA in 78,9% of patients, IgE antibodies to Cr-HSA in 68,4% of patients and IgE to CoHSA in 52,6% of patients. Salivary MCT levels were in strong correlation with IgE levels to Ni-HSA (RSpearman=0,9; p<0,05) and in moderate correlation with Cr-HSA (RSpearman=0,7; p<0,05). The obtained data suggest the prevalence of immediate type reaction to dental materials. Expressed local increase of MCT level is an important diagnostic marker of local inflammatory process initiation. MCT in whole saliva was found only in 3 (16,7%) patients from group 2, the same 3 patients had IgE antibodies to metal ions in blood serum, which indicates IgE-dependent type of reaction. The rest of the patients from group 2, most likely, have a different type of allergic reaction, e. g. delayed or granulocyte-mediated. For reliable diagnosis of allergy to the components of dental materials it is reasonable to measure salivary MCT before and after removal of prosthetic constructions. Salivary MCT level monitoring allows to assess the role of prosthetic constructions for the emergence of IDM and need for their replacement.

Activation of CD4+ T- and NK-lymphocytes by components of dental materials in cases of their bio-intolerance

Aim of the study: the effect of the components of dental materials in vitro on the expression of activation molecules of T-lymphocytes and natural killers (NK) of blood in patients with intolerance to dental materials (IDM). Methods of examination: 22 patients with positive skin application tests (AT) with solutions of metal salts (NiCl2 (3%), CrCl3 (3%), CoCl2 (1%) and complaints of intolerance to dental materials (IDM), and 21 patient without IDM. CD4 +CD25+CD45+ T-lymphocyte and CD16+CD56+CD69+CDE+ NK-lymphocytes were determined after incubation with prosthetic fragments fluid (PFF) and metal salts solution (MSS): Ni-HSA, Cr-HSA, Co-HSA. Results: activation of CD4 + T-lymphocytes in response to stimulation by PFF and MSS was detected. As an outcome of the study, a number of regularities in the expression of markers for T-lymphocytes and NK-lymphocytes activation were established. The results confirm the potential role of CD4+ CD25+CD45+ T-lymphocytes and CD16+CD56+CD69+ NK-lymphocytes in the development of hypersensitivity to CDM. After a 24-hour blood incubation of patients with objective signs of IDM and positive AT results to metal salts with PFF and MSS, the number of CD4+CD25+CD45+ T-lymphocytes, CD16+CD56+CD69+ NK-lymphocytes increased, whereas in patients of the control group it did not. The peripheral blood T-lymphocytes of patients from this group also responded to HSA stimulation by the increased expression of CD25 molecules. Conclusion: the method of CDM hypersensitivity diagnosis by measuring increasing CD4+CD25+CD45+ T-lymphocytes and CD16+CD56+CD69+ NK-lymphocytes using PFF and MSS as stimulants can serve as a reliable test for the diagnosis of intolerance to dental materials.

Determination of basophil activation and IgE antibodies to the components of dental materials in cases of intolerance to dental prosthetics

The aim of the study was to determine the activation of blood basophils and IgE antibodies to the components of dental materials (CDM) in patients with intolerance to dental prosthetics. Materials and methods: we examined 22 patients with positive skin application tests (AT) with metal salts solutions (NiCl2 (3%), CrCl3 (3%), CoCl2 (1%) and complaints of intolerance to dental materials (IDM), and 21 patients without IDM complaints. We determined the levels of CD203c+CD63+ basophils after incubation of blood with incubation liquid containing particles of prosthetics (LPP) and metal salts solutions (MSS): NiCl2, CrCl3, CoCl2, ZnCl2, MnCl2, also measured IgE antibodies to these salts using ELISA. Results: in patients with IDM and skin hypersensitivity to metal salts an increase or decrease of CD203c+basophils after incubation of basophils with LPP and MSS occurred. In patients with skin hypersensitivity to CDM basophils significantly more often and stronger reacted with LPP and metal salts compared to basophils of control group patients. It was established that LPP had the highest diagnostic efficiency (sensitivity 72,7%; specificity 90,5%; AUC 0,86; p=0,0003; with threshold of expression growth for CD203c+63+ basophils equaling 16,68%), compared to MSS as basophil activation inductor. Conclusion: basophil activation test and IgE antibodies determination are recommended for detection of hypersensitivity and allergy in patients with IDM.

Solid-Phase Extraction (SPE) and HPLC Analysis of Toxic Compounds and Comparison of SPE and Liquid-Liquid Extraction. I. Analysis of 4, 4′-Methyl-Enedianiline in Serum. II. Analysis of the Components of Dental Materials

Abstract In this paper, we discuss two subjects concerned with solid phase extraction (SPE) and HPLC analysis of toxic compounds eluted to serum from materials used for medical devices. SPE and liquid-liquid extraction for serum toxic compounds were compared. Firstly, an analysis of a toxic and carcinogenic compound, 4,4′-methylenedianiline (MDA), from polyurethane sterilized by gamma-ray irradiation was studied. Serum MDA was analyzed to assess the potential MDA risk to patients exposed to PU medical devices. MDA was determined by reverse-phase HPLC using an eluent of a mixed solution of ammonium acetate and acetonitrile. An ODS column was used. Detection was carried out by an electrochemical detector (ECD). As liquid-liquid extraction was complex due to deproteinization followed by centrifuge separation and concentration, we substituted SPE. Serum MDA was satisfactorily recovered using Bond Elut C-18, Phenyl and Cyclohexyl columns. The recovery of serum MDA from Bond ElutR C-1, C-2, C-8 and Silica was u...

Mutagenic potential of some chemical components of dental materials.

Abstract Chemical compounds that are used in dental materials or related structurally to compounds that are found in dental materials were tested for bacterial mutagenicity by means of the Ames Test. The results of spot tests and plate incorporation tests indicated that 8 of the compounds were not mutagenic. These same procedures showed that one of the chemicals, p-aminophenylacetic acid, is weakly mutagenic. The data also indicated that the addition of liver extracts containing microsomal enzymes enhanced the mutagenic activity of p-aminophenylacetic acid.

Characterization of components of dental materials and components of tooth structure by differential thermal analysis.

Differential thermal analysis (DTA) has been used to characterize a variety of dental materials and the components of tocth structure. The technic is useful for the rapid comparison of similar materials, quality control, measurement of melting ranges, and the study of reactions occurring at elevated temperatures.