Scoping an interdisciplinary model of student dental therapists in maxillofacial trauma.

Introduction This paper outlines a short pilot programme to assess the feasibility of an interdisciplinary model of involving student dental therapists in the management of maxillofacial trauma patients. It involved dental therapy students attending an oral and maxillofacial surgery trauma review clinic at a major trauma hospital in London, UK.Approach The small cohort of 15 second-year dental hygiene and therapy (BSc in Oral Health) students attended the trauma clinic once a week in pairs, over a period of six weeks, after which they completed a survey questionnaire.Findings No students had previous experience of dealing with trauma patients. The majority (81.8%) had learnt something by attending the clinic. Almost all (91.7%) had not thought previously about the importance of oral hygiene in maxillofacial trauma patients. By the end of the pilot programme, ten students (83.3%) felt that they had a role to play in the care of these trauma patients and they felt valued as members of the wider team.Conclusion These initial findings suggest that the scheme has potential for incorporation of maxillofacial trauma experience within the formal dental therapy curriculum. This would prepare them for future involvement in the management of maxillofacial trauma patients to promote oral health benefits and more widely, to work as a team member in interprofessional health care

Can glass polyalkenoate (glass-ionomer) dental cements be considered bioactive? A review.

OBJECTIVES: This paper reviews the chemical behaviour of glass polyalkenoate (glass-ionomer) dental cements, both conventional and resin-modified, in contact with natural tissues, with the aim of determining whether these materials can be considered to be bioactive. DATA: Relevant papers describing the behaviour of bioactive glasses and ceramics, and glass-ionomer (glass polyalkenoate) cements have been identified using PubMed and Science Direct. This has allowed a comparison to be made between the behaviour of glass-ionomers and the speciality glasses and ceramics that are widely classified as bioactive, a designation considered valid for over fifty years. More recent papers concerning bioactive metals and polymers have also been studied and both in vitro and in vivo studies are included. SOURCES: Have included general papers on the chemistry and biological behaviour of bioactive glasses and ceramics, as well as papers on glass-ionomers dealing with (i) ion release, (ii) bonding to the surface of teeth, (iii) influence on surrounding pH and (iv) interaction with bone. CONCLUSION: The literature shows that glass-ionomers (glass polyalkenoates) have three types of behaviour that are similar to those of bioactive glasses as follows: Formation of direct bonds to living tissue (teeth and bones) without fibrous capsule; release of biologically beneficial ions; and change of the local pH. However, in in vitro tests, they do not cause calcium phosphate to precipitate from solutions of simulated body fluid, SBF. Despite this, studies show that, in patients, glass-ionomers interact chemically with hard tissues and this suggests that may indeed be considered bioactive

Interaction of conventional glass-ionomer cements with hydrated dentin

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Evaluation of biofilm formation on acrylic resin surfaces coated with silicon dioxide: an in situ study.

Biofilm on acrylic resin dental prostheses may cause gingival inflammation. This study evaluated the influence of a silicon dioxide coating layer applied onto acrylic resin on the adhesion of microorganisms. Blocks (5 x 5 x 3 mm) of acrylic resin were evaluated for surface roughness and divided into two groups: control (CG) and coated with silicon dioxide (LG group). The specimens were evaluated by scanning electron microscopy (n = 1) and by contact angle analysis (n = 3). For the in situ study, 20 volunteers wore acrylic palatal devices containing three samples from each group (n = 60) for 2 days. The biofilm formed was quantified by metabolic activity and total biomass using the crystal violet assay. The results were subjected to Bartlett's normality test and Gamma model with random effect for the response variable (α = 5%). The mean contact angle of the coated group was significantly lower than that of the uncoated group (p < 0.05). The metabolic activity of microorganisms in the biofilm on the blocks treated with coating was significantly lower than that of control blocks (p = 0.02). Regarding the amount of extracellular matrix produced by the microorganisms, there was no difference between the CG and LG group (p = 0.05). The application of a silicon dioxide coating on acrylic resin reduced the activity of the polymicrobial biofilm formed in situ. This coating may be advantageous for patients with conventional complete dentures or implants made of acrylic resin and who have motor difficulties that prevent them from cleaning their prostheses properly

Translucency parameter of conventional restorative glass-ionomer cements.

OBJECTIVE: To evaluate the translucency parameter (TP) and contrast ratio (CR) of different conventional restorative glass-ionomer cements (GICs). MATERIALS AND METHODS: Eighteen brands of GICs were evaluated. Five disks of each material were made following ISO 9917-1. The luminous reflectance and Central Bureau of the International Commission on Illumination parameters of disks were evaluated using a colorimeter, against backings of white and black, to obtain the translucent parameter and contrast ratio of different brands of glass-ionomer cements. The correlation between translucency parameter and contrast ratio was assessed with the Pearson correlation test. The translucent and contrast ratio parameters values were submitted to the one-way ANOVA and Tukey test for multiple comparisons (p < 0.05). RESULTS: There was a strong inverse relationship between CR and TP (r2 = 0.94, p < 0.001). The contrast ratio decreased as translucency increased. There were significant differences in TP and CR among brands (p < 0.001). CONLUSIONS: GICs exhibit different translucency and contrast ratio behavior. Some brands of GICs presented very low TP and this condition would be unacceptable for areas with esthetic demands. In addition, TP and CR showed a strong linear relationship. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the knowledge of the translucency and CR of different conventional restorative GICs is important in order to guide clinicians in the selection of restorative GICs for anterior teeth

Antibacterial effect of a fluoride-containing ZnO/CuO nanocomposite

© 2019 Elsevier B.V. Dental materials that are antimicrobial and acid-resistant can inhibit bacterial colonization and demineralization, thereby preventing caries. Zinc and copper are well-known for their antibacterial effect, as is nanostructured ZnO–CuO composite. Minerals such as fluorine and calcium, can remineralize and demineralize teeth. Therefore, we developed novel fluoride-containing ZnO–CuO (ZCF) nanocomposites; to the best of our knowledge, these are the first nanocomposites of this kind. The fluoride concentrations and antibacterial effects of the ZCF nanocomposites were evaluated. Nanocomposites comprising zinc and copper (ZC), and zinc, copper, and fluorine (ZCF), were prepared by a simple one-step homogeneous coprecipitation method at a low temperature (80 °C), without the use of organic solvent or surfactant. The structure and composition of the ZC and ZCF nanocomposites were examined by scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS). Quantitative analysis of the mass concentration was performed by using ZAF correction methods. The fluorine content in nanocomposites was evaluated by using proton-induced gamma emission (PIGE) at the Takasaki Advanced Radiation Research Institute in Japan. By using 96-well microtiter plates, we analyzed the antibiotic susceptibility of ZC, ZCF, and the control buffer (phosphate-buffered saline) with Streptococcus mutans (ATCC 25175). The SEM images showed that ZC and ZCF nanocomposites were composed of 3D flower-like microstructures with diameters of approximately 1 μm. Environmental SEM-EDS analysis revealed that ZC contained 43.2% Cu, 55.1% Zn, 2.2% F, and 0.1% Cl, whereas ZCF contained 47.5% Cu, 40.5% Zn, 6.7% F, and 5.9% Cl. Analysis by PIGE showed that ZCF nanocomposite contained 2553.6 ± 199.2 ppm fluorine, whereas no fluoride was detected in ZC. The control buffer enabled bacterial growth to 4 × 107 ± 9 × 106 CFU/mL, whereas ZC allowed growth of 12 ± 8 CFU/mL, and ZCF showed no bacterial growth. Thus, we developed novel fluoride-containing ZnO–CuO nanocomposites, which exhibited antibacterial effects and have the potential for remineralization, thereby demonstrating their potential as multifunctional dental materials