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Journal of Chromatography. A Nov 2018Since 2011, the World Health Organization has encouraged a global phase-down of the use of dental amalgam and actively supported the use of alternative, resin-based...
Since 2011, the World Health Organization has encouraged a global phase-down of the use of dental amalgam and actively supported the use of alternative, resin-based dental materials. The resins consist of (meth)acrylate monomers derived from Bisphenol A (BPA), such as Bisphenol A glycidyl methacrylate (BisGMA) and Bisphenol A ethoxylate methacrylate (BisEMA) or triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) which lack the BPA backbone. Besides monomers, other compounds such as photoinitiators and stabilizing agents can be present in the dental resin matrices. The current study consists in the development of an analytical method for the separation and identification of dental material components using LC-QTOF-MS. The developed method was applied on several dental material ingredients, unpolymerized composite resins, and a common dental sealant. The acquired high resolution accurate-mass data was analyzed using suspect screening with an in-house developed library. Next to the main components, various isomers and impurities related to the production of the main component have been detected and identified in the dental material ingredients. In total, 39 chemicals have been identified in the analyzed dental materials. On average 15 chemicals have been identified. Major components, such as BisEMA, BisGMA and TEGDMA were identified although they were not always stated in the material safety data sheets. Minor components included photoinitiators, such as ethyl 4-dimethyl aminobenzoate (EDMAB) and (meth)acrylates impurities originating from production of main ingredients.
Topics: Chromatography, Liquid; Composite Resins; Dental Materials; Mass Spectrometry; Materials Testing; Pit and Fissure Sealants
PubMed: 30266234
DOI: 10.1016/j.chroma.2018.09.039 -
Operative Dentistry 2016The topic of material tissue interaction has gained increasing interest over recent decades from both the dental profession and the public. The primary goal initially... (Review)
Review
The topic of material tissue interaction has gained increasing interest over recent decades from both the dental profession and the public. The primary goal initially was to avoid adverse reactions after the application of dental materials. New laboratory test methods have been developed, and currently premarket testing programs, which attempt to guarantee a basic level of patient safety, are legally required worldwide. The dentist is responsible for selecting the correct indication as well as the proper handling of any newly emerging risk. Apart from this phenomenon-oriented "inert materials concept," the "analytical concept" focuses primarily on analyzing the reasons for adverse reactions, and identifying their associated modifying factors, in order to prevent them or to develop new and more biocompatible materials. The "concept of bioactivity" involves addressing the possibility of positively influencing tissue by materials application, such as the generation of tertiary dentin or antibacterial effects. Finally, tissue regeneration may be supported and promoted by the use of various suitable materials (matrices/scaffolds) into which stem cells can migrate or be seeded, leading to cell differentiation and the generation of new tissue. These new dental materials must also fulfill additional requirements such as controlled degradability in order to be suitable for clinical use. Clearly, the field of material tissue interaction is complex and comprises a wide range of issues. To be successful as dentists in the future, practitioners should remain informed of these important new developments and have the argumentative competence to both properly advise and treat their patients.
Topics: Biocompatible Materials; Dental Materials; Guided Tissue Regeneration, Periodontal; Humans; Hypersensitivity; Mouth Diseases; Off-Label Use; Tissue Engineering
PubMed: 26645359
DOI: 10.2341/15-249-BL -
BMC Oral Health Jul 2023This study aims to evaluate the primary teeth undergoing amputation due to dental caries or trauma clinically and radiologically.
AIM
This study aims to evaluate the primary teeth undergoing amputation due to dental caries or trauma clinically and radiologically.
MATERIAL AND METHODS
The amputation treatment of 90 primary teeth of 58 patients (Female: 20, Male: 38) aged 4-11 years was evaluated clinically and radiologically. Calcium Hydroxide was used for amputation in this study. Composite or amalgam was preferred as filling material in the same session of the patients. Clinical/radiological (Periapical/Panoramic X-ray) examination was performed on the teeth that were unsuccessful in treatment, on the day of the patient's complaint, and at the end of 1 year in the others.
RESULTS
According to the clinical and radiological findings of the patients, 14.4% of the boys and 12.3% of the girls were unsuccessful. Amputation in male was a need in the 6-7 age group with a rate of 44.6% at most. Amputation in females was a need in the 8-9 age group with a rate of 52% at most.
CONCLUSION
Success in amputation treatment depends on the tooth, the dentist, and the dental material applied.
Topics: Humans; Male; Female; Child; Dental Caries; Tooth, Deciduous; Dental Materials; Calcium Hydroxide; Dental Amalgam
PubMed: 37415166
DOI: 10.1186/s12903-023-03171-z -
European Journal of Oral Sciences Oct 2018In dentistry, isotropic materials, such as metals, ceramics, and polymers, are used. Their properties are not related to any specific direction of the material... (Review)
Review
In dentistry, isotropic materials, such as metals, ceramics, and polymers, are used. Their properties are not related to any specific direction of the material microstructure. There is a trend toward non-metallic, adhesive, and minimally invasive dentistry. This is in line with the conceptual change seen in the automobile industry, in which the basis of car structures has changed from body-on-frame designs to unibody designs. In unibody designs, all structural parts of the body of the car mechanically form a single structural entity. In modern adhesive dentistry, remaining tooth substance and the dental material form unibody designs, enabling preservation of tooth substance. Biological structures are created to withstand loading and are light in weight. The structural designs of elements in these biological materials are, to a large extent, based on fibrous material. More attention has been paid to mimicking fibrous structures of dental hard tissues by synthetic fiber-reinforced composites. This overview reports key features of natural fibrous elements and how they are utilized in dentistry. Special emphasis is placed on the aspects of interfacial adhesion of restorative materials, especially ceramics to resin-based materials and their role in the unibody design of the tooth-restoration system.
Topics: Biomimetic Materials; Ceramics; Composite Resins; Dental Cements; Dental Materials; Dental Prosthesis; Dental Prosthesis Design; Dental Restoration, Permanent; Humans
PubMed: 30178556
DOI: 10.1111/eos.12419 -
Dental Materials : Official Publication... Jan 2018An important tool in materials research, development and characterization regarding mechanical performance is the testing of fracture toughness. A high level of accuracy... (Review)
Review
BACKGROUND
An important tool in materials research, development and characterization regarding mechanical performance is the testing of fracture toughness. A high level of accuracy in executing this sort of test is necessary, with strict requirements given in extensive testing standard documents. Proficiency in quality specimen fabrication and test requires practice and a solid theoretical background, oftentimes overlooked in the dental community.
AIMS
In this review we go through some fundamentals of the fracture mechanics concepts that are relevant to the understanding of fracture toughness testing, and draw attention to critical aspects of practical nature that must be fulfilled for validity and accuracy in results. We describe our experience with some testing methodologies for CAD/CAM materials and discuss advantages and shortcomings of different tests in terms of errors in testing the applicability of the concept of fracture toughness as a single-value material-specific property.
Topics: Dental Materials; Dental Restoration Failure; Dental Stress Analysis; Materials Testing; Surface Properties
PubMed: 29203072
DOI: 10.1016/j.dental.2017.11.016 -
American Journal of Dentistry Aug 2023To evaluate and compare the effects of different scaling and polishing techniques on the surface roughness of four different restorative materials.
PURPOSE
To evaluate and compare the effects of different scaling and polishing techniques on the surface roughness of four different restorative materials.
METHODS
72 specimens were prepared, molded to a size of 8.0 by 2.0 mm, and cured according to the manufacturers' instructions. The specimens were stored at 37°C for 24 hours and then thermocycled for 5,000 cycles (from 55°C to 5°C) to simulate 6 months of clinical use. Surface roughness (Ra/average and Rz/max-overall heights) was calculated using a stylus profilometer by subtracting the simulated treatments of hand scaling, ultrasonic scaling, and air polishing from the baseline measurements. The difference in Ra and Rz data were compared independently for each measurement using a two-way ANOVA on Ranks and the Holm-Sidak test, with α< 0.05 used to determine significance.
RESULTS
Irrespective of the scaling or polishing technique employed, flowable bulk fill demonstrated the lowest Ra and Rz values. Hand scaling exhibited the highest roughness and variability among the other techniques, regardless of the materials tested (P< 0.001). Air polishing with glycine resulted in the lowest roughness values across all tested materials, with the exception of the tested bioactive restorative material group.
CLINICAL SIGNIFICANCE
Regarding surface roughness, air polishing with glycine may be an effective and safe intervention for periodontal maintenance of subgingival restorations compared to the other tested scaling methods.
Topics: Dental Scaling; Analysis of Variance; Dental Materials; Glycine; Ultrasonics
PubMed: 37587032
DOI: No ID Found -
American Journal of Dentistry Jun 2021To evaluate the stress distribution of inlays fabricated with restorative materials of different elastic moduli under two functional loading conditions by using...
PURPOSE
To evaluate the stress distribution of inlays fabricated with restorative materials of different elastic moduli under two functional loading conditions by using three-dimensional (3D) finite element analysis (FEA) models of a second maxillary premolar.
METHODS
A 3D model of a sound maxillary left second premolar and its supporting bone was generated in a previous study and reutilized under permission of the authors for the present study. Inlay models obtained from the sound tooth were then assigned according to the type and inherent elastic modulus of the restorative material used, as follows: microhybrid composite (Filtek Z250); indirect resin composite (Paradigm); lithium disilicate reinforced glass ceramic (IPS e.max Press); and type III gold alloy. The geometric models were then exported for 3D FEA. All materials were considered isotropic, homogeneous, and linear-elastic. A static load of 100 N was applied in two conditions: axially at both cusps (axial loading) and at the mesial marginal ridge (proximal loading). Maximum principal and von Mises stresses were used to analyze the stress distribution pattern in inlays and sound premolar models.
RESULTS
Under axial loading condition, either resin composite, ceramic or type III gold alloy inlays generated a similar biomechanical behavior, especially in terms of stress distribution in the remaining tooth structure and cusp deflection. However, higher tensile stresses were observed along the proximal gingival margin of the preparation under proximal loading in the Z250 and Paradigm models, as well as a greater cusp deflection. In contrast, a deflection like the sound model was observed in the ceramic and gold inlay models.
CLINICAL SIGNIFICANCE
Restorative materials with higher elastic modulus, such as dental ceramics and type III gold alloys, seem to be the best choice for maxillary premolars restored with inlays in the presence of occlusal contact on the marginal ridge.
Topics: Bicuspid; Composite Resins; Dental Materials; Dental Porcelain; Dental Stress Analysis; Finite Element Analysis; Inlays; Materials Testing; Stress, Mechanical
PubMed: 34143589
DOI: No ID Found -
The International Journal of... Dec 2023To evaluate and compare the effect of accelerated aging and coffee immersion on the microhardness and gloss of a new computer-aided design and computer-aided...
PURPOSE
To evaluate and compare the effect of accelerated aging and coffee immersion on the microhardness and gloss of a new computer-aided design and computer-aided manufacturing (CAD/CAM) hybrid material (Crystal Ultra) to those of contemporary restorative materials.
MATERIALS AND METHODS
A total of 160 specimens (12 × 14 × 1 mm ± 0.05 mm) were obtained from IPS e.max (IPS), VITA Enamic (VE), Crystal Ultra (CU), Lava Ultimate (LU), and CeraSmart (CS) high-translucency CAD/CAM blocks. The Vickers microhardness and gloss of the specimens were determined after thermocycling and coffee immersion. Data analysis was performed using SPSS (α = .05).
RESULTS
IPS and CS specimens exhibited the highest (572.66 ± 11.30) and lowest (61.92 ± 3.91) microhardness, respectively. The highest gloss was observed with IPS specimens (3.31 ± 0.32), and LU specimens showed the lowest gloss (2.33 ± 0.06). A significant difference in gloss was observed between the materials at all measurement intervals (P < .01), except at T0 (P = .43). IPS specimens showed no significant changes in either group at any measurement interval.
CONCLUSIONS
The microhardness and gloss of the new CU material were comparable to those of the tested contemporary hybrid restorative materials. Glass-ceramic showed superior hardness and gloss compared to hybrid restorative materials. Accelerated aging with thermocycling and staining significantly affected the microhardness and gloss of all tested CAD/CAM materials.
Topics: Dental Porcelain; Coffee; Immersion; Materials Testing; Ceramics; Dental Materials; Computer-Aided Design; Surface Properties
PubMed: 38112735
DOI: 10.11607/ijp.7726 -
Dento Maxillo Facial Radiology Sep 2022The purpose of this systematic review was to search in literature in which severity unintended effects are caused by dental materials in magnetic resonance imaging...
OBJECTIVES
The purpose of this systematic review was to search in literature in which severity unintended effects are caused by dental materials in magnetic resonance imaging (MRI), such as to evaluate whether these artifacts hamper the diagnosis in the head and neck region.
MATERIALS AND METHODS
Clinical studies showing the severity of artifacts which dental materials are capable of causing in MRI of head and neck, such as their influence on diagnostic accuracy, were included in this review. The searches were conducted in four electronic databases (PubMed/Medline, Embase, Scopus and Web of Science), and a manual search was made in the reference lists of papers screened for full-text reading. Risk of bias was assessed using "Quality Assessment Tool for Diagnostic Accuracy Studies-2" (QUADAS-2). The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the quality of evidence.
RESULTS
From 151 studies selected for full-reading, 19 were considered eligible for this review. Artifacts caused by orthodontic appliances were well-documented, and stainless steel brackets were the materials most likely to cause artifacts in MR imaging of head and neck. The literature was scarce for dental implants and restorations. Diagnoses within the oral cavity, but also those of the brain and craniofacial structures, were affected.
CONCLUSION
Artifacts caused by orthodontic appliances may affect the diagnosis in oral cavity and craniofacial structures. Data regarding dental implants and prosthodontics restorations were inconclusive. The severity of artifacts in MRI and their influence on diagnosis is dependent on dental material features, location in the oral cavity, and magnetic resonance parameters.
Topics: Artifacts; Dental Implants; Dental Materials; Humans; Magnetic Resonance Imaging; Mouth; Orthodontic Appliances
PubMed: 35348371
DOI: 10.1259/dmfr.20210450 -
Primary Dental Journal Nov 2019With increasing patient expectation for aesthetic dental restorations, there has been a drive towards developing ceramic materials to meet this expectation. Multiple...
With increasing patient expectation for aesthetic dental restorations, there has been a drive towards developing ceramic materials to meet this expectation. Multiple ceramic systems have been introduced over the past four decades with considerable advances in material properties. Survival rates of all-ceramic crowns differ by type of ceramic used, fabrication method and clinical indication. Zirconia and lithium disilicate are the most commonly used contemporary ceramic materials in dentistry. Survival data for these types of restorations appears to be promising; however, there is a lack of high-quality long-term clinical data on the success of these restorations. In the absence of robust longitudinal clinical research, laboratory studies have provided some useful information on the performance of ceramic restorations. Further high quality long-term clinical studies are needed to inform us of modes of failure of these restorations and the range of clinical circumstances in which each type of ceramic restoration may be used.
Topics: Ceramics; Crowns; Dental Materials; Dental Porcelain; Dental Restoration Failure; Humans; Zirconium
PubMed: 31666170
DOI: 10.1308/205016819827601527