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International Journal of Paediatric... Jan 2024Magnetic resonance imaging (MRI) has become an important diagnostic tool for paediatric patients. The association between dental restorations and MRI...
BACKGROUND
Magnetic resonance imaging (MRI) has become an important diagnostic tool for paediatric patients. The association between dental restorations and MRI artefacts/distortions, however, is unclear.
AIM
To investigate the association between dental restorations and artefacts in head MRI in children.
DESIGN
This retrospective analysis included patients who underwent head MRI and dental examination at Ramathibodi Hospital from January 2015 to March 2021. From dental records and dental radiographs, a dentist reviewed the amount and type of restorative materials used. Two radiologists examined the MRI scans in five sequences for the presence of distortions and quantified the magnitude and grading of any artefacts.
RESULTS
Ninety-four patients aged 3-15 years were included. Twenty-four patients who received preformed metal crowns (PMCs) had MRI distortions. Subjects with no restorations or with tooth-coloured material or amalgam restorations or both did not exhibit distortions. The number of PMCs was related to the size of an artefact. Almost all distortions were confined to the oral cavity and maxillary sinus and did not affect the diagnostic brain area.
CONCLUSION
Among the commonly used dental restorative materials for children, only PMCs were associated with artefacts on head MRI scans.
PubMed: 38195814
DOI: 10.1111/ipd.13155 -
PloS One 2023This study investigates the biomechanical performance of various dental materials when filled in different cavity designs and their effects on surrounding dental...
This study investigates the biomechanical performance of various dental materials when filled in different cavity designs and their effects on surrounding dental tissues. Finite element models of three infected teeth with different cavity designs, Class I (occlusal), Class II mesial-occlusal (MO), and Class II mesio-occluso-distal (MOD) were constructed. These cavities were filled with amalgam, composites (Young's moduli of 10, 14, 18, 22, and 26 GPa), and glass carbomer cement (GCC). An occlusal load of 600 N was distributed on the top surface of the teeth to carry out simulations. The findings revealed that von Mises stress was higher in GCC material, with cavity Class I (46.01 MPa in the enamel, 23.61 MPa in the dentin), and for cavity Class II MO von Mises stress was 43.64 MPa, 39.18 MPa in enamel and dentin respectively, while in case of cavity Class II MOD von Mises stress was 44.67 MPa in enamel, 27.5 in the dentin. The results showed that higher stresses were generated in the non-restored tooth compared to the restored one, and increasing Young's modulus of restorative composite material decreases stresses in enamel and dentin. The use of composite material showed excellent performance which can be a good viable option for restorative material compared to other restorative materials.
Topics: Finite Element Analysis; Composite Resins; Elastic Modulus; Glass Ionomer Cements; Dental Restoration, Permanent; Dental Stress Analysis; Stress, Mechanical
PubMed: 38128035
DOI: 10.1371/journal.pone.0295582 -
The British Journal of Dermatology May 2024Concerns regarding contact allergies and intolerance reactions to dental materials are widespread among patients. Development of novel dental materials and less frequent...
BACKGROUND
Concerns regarding contact allergies and intolerance reactions to dental materials are widespread among patients. Development of novel dental materials and less frequent amalgam use may alter sensitization profiles in patients with possible contact allergy.
OBJECTIVES
To analyse current sensitization patterns to dental materials in patients with suspected contact allergy.
METHODS
This retrospective, multicentre analysis from the Information Network of Departments of Dermatology (IVDK) selected participants from 169 834 people tested in 2005-2019 and registered with (i) an affected area of 'mouth' (and 'lips'/'perioral'), (ii) with the dental material in question belonging to one of three groups (dental filling materials, oral implants or dentures or equivalents) and (iii) with patch-testing done in parallel with the German baseline series, (dental) metal series and dental technician series.
RESULTS
A total of 2730 of 169 834 tested patients met the inclusion criteria. The patients were predominantly women (81.2%) aged ≥ 40 years (92.8%). The sensitization rates with confirmed allergic contact stomatitis in women (n = 444) were highest for metals (nickel 28.6%, palladium 21.4%, amalgam 10.9%), (meth)acrylates [2-hydroxyethyl methacrylate (HEMA) 4.8%] and the substances propolis (6.8%) and 'balsam of Peru' (11.4%). The most relevant acrylates were HEMA, 2-hydroxypropyl methacrylate, methyl methacrylate, ethylene glycol dimethacrylate and pentaerythritol triacrylate. Few men were diagnosed with allergic contact stomatitis (n = 68); sensitization rates in men were highest for propolis (14.9%) and amalgam (13.6%).
CONCLUSIONS
Allergic contact stomatitis to dental materials is rare. Patch testing should not only focus on metals such as nickel, palladium, amalgam and gold, but also (meth)acrylates and the natural substances propolis and 'balsam of Peru'.
Topics: Humans; Female; Male; Retrospective Studies; Dermatitis, Allergic Contact; Adult; Middle Aged; Dental Materials; Patch Tests; Dental Amalgam; Aged; Adolescent; Young Adult; Child; Methacrylates; Balsams; Dental Implants; Stomatitis; Propolis; Dentures; Germany; Allergens; Child, Preschool
PubMed: 38123140
DOI: 10.1093/bjd/ljad525 -
Brazilian Journal of Oral Sciences 2023Better understanding of dentists' decision-making about defective restorations is needed to close the evidence-practice gap (EPG). this study aimed to quantify the EPG...
Better understanding of dentists' decision-making about defective restorations is needed to close the evidence-practice gap (EPG). this study aimed to quantify the EPG about defective restorations and identify dentist factors associated with this EPG. 216 dentists from São Paulo State, Brazil, completed a questionnaire about three clinical case scenarios involving defective composite restorations with cementum-dentin margins (case 1) and enamel margins (case 2), and an amalgam (case 3) restoration. Dentists were asked what treatment, if any, they would recommend, including preventive treatment, polishing, re-surfacing, or repairing the restoration, or replacing the entire restoration. Replacing the entire restoration in any of these three scenarios was classified as inconsistent with the evidence, comprising an EPG. Bivariate analyses using Chi-square, ANOVA, or multiple comparison tests were performed (p<.05). for defective composite restorations, 49% and 55% of dentists chose to replace the entire restoration for cases 1 and 2, respectively. Twenty-nine percent of dentists chose to replace the entire amalgam restoration. Dentists were significantly more likely to choose to replace the defective amalgam restoration than the composite restoration with a defect at the cementum-dentin margins or the enamel margins (both at p < .001). Female dentists were more likely to choose a conservative treatment than male dentists for cases 1 (p=.034) and 2 (p=.009). Dentists with a higher percentage of patients interested in individualized caries prevention were also more conservative in case 1 (p=.045). a substantial EPG regarding treatment decisions for defective restorations exists, especially for composite restorations. This study adds to the international evidence that an EPG exists in this clinical area and that global strategies need to be developed to close the gap.
PubMed: 38077621
DOI: 10.20396/bjos.v22i00.8671640 -
International Dental Journal Dec 2023Dental restorative procedures remain a cornerstone of dental practice, and for many decades, dental amalgam was the most frequently employed material. However, its use... (Review)
Review
Dental restorative procedures remain a cornerstone of dental practice, and for many decades, dental amalgam was the most frequently employed material. However, its use is declining, mainly driven by its poor aesthetics and by the development of tooth-coloured adhesive materials. Furthermore, the Minamata Convention agreed on a phase-down on the use of dental amalgam. This concise review is based on a FDI Policy Statement which provides guidance on the selection of direct restorative materials as alternatives to amalgam. The Policy Statement was informed by current literature, identified mainly from PubMed and the internet. Ultimately, dental, oral, and patient factors should be considered when choosing the best material for each individual case. Dental factors include the dentition, tooth type, and cavity class and extension; oral aspects comprise caries risk profiles and related risk factors; and patient-related aspects include systemic risks/medical conditions such as allergies towards certain materials as well as compliance. Special protective measures (eg, a no-touch technique, blue light protection) are required when handling resin-based materials, and copious water spray is recommended when adjusting or removing restorative materials. Cost and reimbursement policies may need to be considered when amalgam alternatives are used, and the material recommendation requires the informed consent of the patient. There is no single material which can replace amalgam in all applications; different materials are needed for different situations. The policy statement recommends using a patient-centred rather than purely a material-centred approach. Further research is needed to improve overall material properties, the clinical performance, the impact on the environment, and cost-effectiveness of all alternative materials.
PubMed: 38071154
DOI: 10.1016/j.identj.2023.11.004 -
Operative Dentistry Jan 2024The aim was to compare intrapulp temperature (IPT) changes when flat-fissure diamond burs and pear-shaped tungsten carbide burs were used to cut tooth structure,...
OBJECTIVE
The aim was to compare intrapulp temperature (IPT) changes when flat-fissure diamond burs and pear-shaped tungsten carbide burs were used to cut tooth structure, amalgam, and composite resin with and without water coolant.
METHODS
Thermocouples were inserted into the pulp chamber of extracted intact mandibular molars. The thermocouples were connected to an electronic thermometer that detects temperature every second to an accuracy of 0.1°C. IPT changes were recorded while using a high-speed handpiece during MOD cavity preparations (n=40), composite resin removal (n=40), and amalgam removal (n=40). A two-way ANOVA was used for each procedure to test for the effect of bur (pear-shaped tungsten carbide vs flat-fissured diamond) and water coolant (on vs off), with significant main effects (α=0.05) further analyzed using Tukey's multiple comparison test.
RESULTS
During MOD cavity preparation, water coolant reduced changes in IPT (0.03±0.27°C) compared to no water coolant (1.27±0.29°C) when tungsten carbide burs were used (p<0.05) but not when diamond burs were used. During composite resin removal, tungsten carbide burs had less changes in IPT (0.55±0.18°C) compared to diamond burs (1.66±0.50°C) with no water coolant (p<0.05). Water coolant also reduced changes in IPT (0.09±0.14°C) compared to no water coolant (1.66±0.50°C) when diamond burs were used (p<0.01). Water coolant did not significantly affect IPT when tungsten carbide burs were used. During amalgam removal, tungsten carbide burs had lower changes in IPT (0.56±0.15°C) compared to diamond burs (1.88±0.43°C) with no water coolant (p<0.05). Water coolant also significantly reduced changes in IPT (0.71±0.2°C) compared to no water coolant (1.88±0.43°C) when diamond burs were used (p<0.05) but not when tungsten carbide burs were used.
CONCLUSIONS
Water coolant reduced IPT changes when drilling tooth structure with tungsten carbide burs, but not when removing amalgam or composite. Conversely, water coolant reduced IPT changes when drilling with flat fissure diamond burs to remove amalgam and composite, but not when removing tooth structure. When amalgam and composite were removed without water coolant, the tungsten carbide burs resulted in lower IPT changes than when flat fissure diamond burs were used in the same way.
Topics: Temperature; Water; Dental High-Speed Equipment; Composite Resins; Tungsten Compounds; Diamond; Surface Properties
PubMed: 38057997
DOI: 10.2341/23-033-L -
Dental Research Journal 2023Similarity in the appearance of a monolithic restoration with the adjacent teeth is necessary. This study aims to influence the foundation material type and ceramic...
BACKGROUND
Similarity in the appearance of a monolithic restoration with the adjacent teeth is necessary. This study aims to influence the foundation material type and ceramic thickness on the final color of zirconia-reinforced lithium silicate (ZLS) ceramic.
MATERIALS AND METHODS
In this experimental study, the A2 translucent blocks of ZLS were sectioned into rectangular specimens with thicknesses 1, 1.5, and 2 mm ( = 15). Substructure materials include resin composite (B1, D2, A2, A3, and C3), nickel chrome alloy, amalgam, and white and black substrate. Substructure material of resin composite with A2 color was proposed as the control group. The value of the color difference (ΔE) is calculated by the CIEDE2000 formula. Data analysis was accomplished by two-factor repeated measures ANOVA and one-sample -test (α =0.05).
RESULTS
The mean value of maximum ΔE with a black substrate (12.13 ± 0.17) at 1 mm ceramic thickness and the mean value of minimum ΔE with B1 resin composite foundation material (0.02 ± 0.17) at 2 mm ceramic thickness are visible. The significant effect of the foundation restoration type, thickness, and interaction between them is visible on ΔE ( < 0.001).
CONCLUSION
Different thickness is required to meet ideal esthetic outcomes with different substrates. Under the conditions of this investigation, zirconia-reinforced lithium silicate over black, white, nickel-chromium, and amalgam did not meet acceptable outcomes.
PubMed: 38020248
DOI: No ID Found -
British Dental Journal Nov 2023
Topics: Dental Amalgam; Dental Restoration, Permanent
PubMed: 38001180
DOI: 10.1038/s41415-023-6572-4 -
Oral Surgery, Oral Medicine, Oral... Mar 2024We investigated the influence of voxel and field of view (FOV) sizes on expression of the volumetric alteration artifact (VAA) of 5 high-density materials in 2 cone beam...
OBJECTIVE
We investigated the influence of voxel and field of view (FOV) sizes on expression of the volumetric alteration artifact (VAA) of 5 high-density materials in 2 cone beam computed tomography (CBCT) devices.
STUDY DESIGN
Cylinders of amalgam, cobalt-chromium, gutta-percha, titanium, and zirconium were individually positioned in a polymethyl methacrylate phantom. OP300 Maxio and ProMax 3D Classic CBCT devices were used to acquire images with varying voxel and FOV sizes, totaling 585 scans. Two evaluators segmented the high-density cylinder images to obtain the tomographic volumes. The difference between the tomographic and physical volume of each cylinder (i.e., volumetric alteration) was calculated. Statistical analysis was conducted with multiway ANOVA and the Tukey post hoc test (α = 5%). Evaluator reliability was measured with the intraclass correlation coefficient (ICC).
RESULTS
All studied parameters and nearly all interactions influenced the VAA (P < .05). The post hoc test demonstrated less volumetric alteration for the smallest voxel sizes, 61 × 78 mm FOV, and gutta-percha for OP300, and for the smallest voxel sizes, 80 × 80 mm FOV, and gutta-percha and titanium for ProMax 3D (P < .05). The ICC demonstrated perfect reliability (1.00).
CONCLUSIONS
Voxel and FOV sizes influenced VAA expression. Using smaller voxel sizes, the 61 × 78 mm FOV for OP300 and the 80 × 80 mm FOV for ProMax 3D, and materials with lower density and lower atomic number reduced VAA expression.
Topics: Humans; Artifacts; Gutta-Percha; Reproducibility of Results; Titanium; Cone-Beam Computed Tomography
PubMed: 37980244
DOI: 10.1016/j.oooo.2023.10.004 -
International Journal of Dentistry 2023Evaluating the level of dental students' competence is crucial for validating their preparedness for graduation. Confidence has a significant role in achieving...
Dental Students' Perception and Self-Perceived Confidence Level in Key Dental Procedures for General Practice and the Impact of Competency Implementation on Their Confidence Level, Part I (Prosthodontics and Conservative Dentistry).
BACKGROUND
Evaluating the level of dental students' competence is crucial for validating their preparedness for graduation. Confidence has a significant role in achieving competence. There are limited studies that assess the level of self-perceived confidence among final-year dental students regarding their ability to conduct key dental procedures. This study aims to assess the self-perceived confidence level of final-year dental students in performing essential dental procedures across various dental disciplines and to assess the effect of implementing competencies in the curriculum on the self-perceived confidence level of students by comparing two cohorts of final-year students in two different years 2016 (Traditional Cohort) and 2019 (Competencies Cohort).
MATERIALS AND METHODS
An questionnaire was answered by two cohorts of final-year dental students: one group in 2016 before the implementation of the competency-based assessment system (group 1, = 153), and the other in 2019 after the implementation of this system (group 2, = 199), the same questionnaire was used for both cohorts. The results from the two groups were compared regarding the degree of self-perceived confidence in conducting key dental procedures. The data were analysed using SPSS statistics and Levene's Test for Equality of Variances and -test for Equality of Means calculated.
RESULTS
Group 1 showed a significantly higher means of self-perceived confidence levels than group 2 in the ability to conduct seven out of the 20 prosthodontics procedures studied: providing patients with Cobalt-Chromium (Co-Cr) removable partial dentures (RPD) (3.77 vs. 3.56), providing the patient with Acrylic RPD (3.70 vs. 3.23), treatment planning for partially edentulous patients (3.83 vs. 3.34), giving OHIs for denture patients (4.17 vs. 3.95), dealing with CD postinsertion complaints (3.97 vs. 3.76), giving postinsertion instructions for removable prostheses cases (4.12 vs. 3.82), and providing patients with immediate dentures (2.67 vs. 2.32). The same applies to 6 out of 16 conservative dentistry procedures: placing anterior composite (4.41 vs. 4.12), placing posterior composite (4.43 vs. 3.88), placing posterior amalgam (4.29 vs. 4.02), placing matrix band for Class II restorations (4.24 vs. 3.71), placing a prefabricated post (3.34 vs. 2.88), and placing fiber post (3.45 vs. 3.34). On the other hand, group 2 shows higher means of self-perceived confidence than group 1 in only two conservative dentistry procedures: onlay restorations (2.18 vs. 2.76) and inlay restorations (2.22 vs. 2.75). No significant differences in means of self-perceived confidence were found between the two groups in the remaining 21 procedures studied.
CONCLUSIONS
This study has shown that final-year dental students have high self-perceived confidence levels in doing simple dental procedures yet less confidence in more complex ones. Although, students' self-perceived confidence decreases after the introduction of a competency-based assessment system. Competency implementation and execution criteria may differ between schools which may have an impact on final outcomes. Hence, there is a need for regular evaluation of competencies being assessed to maintain a curriculum that is up to date.
PubMed: 37868108
DOI: 10.1155/2023/2015331