Oral Health Status of Healthcare Workers in Ilembula/Tanzania during the COVID-19 Condition.

The challenge of reduced dental treatment and education infrastructure in the Tanzanian highlands affects the oral health situation of both the general population and local healthcare workers. The aim of this study was to investigate the oral health status of healthcare workers at Ilembula Lutheran Hospital (ILH), Tanzania, during the COVID-19 pandemic. In total, 134 healthcare workers (62 women, 72 men; mean age 36.48 ± 9.56 years, range 19-59 years; median age 35.00 years) participated in this cross-sectional study, conducted from 12 February to 27 February. A dental examiner trained in oral health screening performed the oral health data collection. Data collection was performed by probability sampling using the Ilembula Data Collection Form-Oral Health (IDCF-Oral Health) questionnaire distributed in paper form. Ethical approval was obtained from the National Institute for Medical Research/Tanzania. The decayed, missing, and filled teeth (DMF/T) index proposed by the World Health Organization (WHO) was used with the associated caries measurement method and the simplified oral hygiene index (OHI-S). Details regarding edentulism, nutritional habits, and socio-economic factors were collected. Statistical analysis was performed using linear regression (α = 0.05). The average DMF-T index was 3.33 ± 0.82, with age, gender, meal frequency, and soft drink consumption significantly influencing the index. No evidence of dental plaque was detected in 43.3% of the participants. Of the participants, 32.8% required prosthetic treatment (Kennedy Class III), while 16.4% needed it for acute malocclusions. Oral hygiene products were used in 97% of cases. A total of 35.8% of the participants had an OHI-S score of up to 1.0, with (p < 0.001) age and (p < 0.001) sex having a significant influence on the index. The current oral health situation of healthcare workers at ILH shows a moderate need for restorative and prosthetic treatment in rural Tanzania. Despite the COVID-19 pandemic, there was no change in the need for dental treatment, which may be explained by the generally restricted access to dental healthcare in the investigated region. The development of an interdisciplinary oral health prophylaxis system could help to reduce the need for future treatments

In Vitro Analysis of the Mechanical Properties of Hypoallergenic Denture Base Resins

The development of hypoallergenic denture resins is key to the treatment of patients with allergies to polymethyl methacrylate (PMMA). In this study, the in vitro mechanical properties of hypoallergenic and PMMA denture base resins were compared. Ninety-six test specimens of hypoallergenic denture base resins (Polyan Plus®, Sinomer, TMS Acetal Dental, Erkocryl) and 72 test specimens of PMMA-based denture base resins (Paladon 65, PalaXpress, SR-Ivocap) were fabricated. The flexural strength, elastic modulus, compressive strength, macro- and microhardness, average roughness, water absorption, and water solubility of the resins were measured. None of the hypoallergenic denture resins matched all the mechanical properties of the PMMA resins. Polyan Plus® and TMS Acetal Dental were closest to matching the mechanical properties of the PMMA resins, and TMS Acetal Dental had some superior properties. Consequently, Polyan Plus® and TMS Acetal Dental hypoallergenic resins are recommended for further investigation as potential alternatives to PMMA resins for the fabrication of removable dentures

The Digital Abutment Check: An Improvement of the Fully Digital Workflow

By using modern digitalization techniques, an existing denture can be digitized and aid the provision of a new implant-supported denture according to a fully digital workflow. This includes fully navigated implant surgery and results in an immediately provided prosthetic restoration. However, even with the current digital workflow, it is challenging to achieve a definitive prosthetic restoration in a single treatment session. In order to achieve a definitive denture in as few treatment sessions as possible, we have implemented the digital abutment test. This test modified the existing data set and determined the final restoration. In the present case, the preexisting maxillary removable complete denture was converted into a fixed immediate restoration using the fully digital workflow. The workflow is divided into two treatment phases, each with three treatment sessions, where part of the second phase involves an innovative digital abutment check. The illustrated case shows an effective use of current digital possibilities. Special attention was also paid to a minimally invasive course of therapy

Staphylococcus aureus and Pseudomonas aeruginosa express and secrete human surfactant proteins.

Surfactant proteins (SP), originally known from human lung surfactant, are essential to proper respiratory function in that they lower the surface tension of the alveoli. They are also important components of the innate immune system. The functional significance of these proteins is currently reflected by a very large and growing number of publications. The objective goal of this study was to elucidate whether Staphylococcus aureus and Pseudomonas aeruginosa is able to express surfactant proteins. 10 different strains of S. aureus and P. aeruginosa were analyzed by means of RT-PCR, Western blot analysis, ELISA, immunofluorescence microscopy and immunoelectron microscopy. The unexpected and surprising finding revealed in this study is that different strains of S. aureus and P. aeruginosa express and secrete proteins that react with currently commercially available antibodies to known human surfactant proteins. Our results strongly suggest that the bacteria are either able to express 'human-like' surfactant proteins on their own or that commercially available primers and antibodies to human surfactant proteins detect identical bacterial proteins and genes. The results may reflect the existence of a new group of bacterial surfactant proteins and DNA currently lacking in the relevant sequence and structure databases. At any rate, our knowledge of human surfactant proteins obtained from immunological and molecular biological studies may have been falsified by the presence of bacterial proteins and DNA and therefore requires critical reassessment

Staphylococcus aureus and Pseudomonas aeruginosa Express and Secrete Human Surfactant Proteins

Surfactant proteins (SP), originally known from human lung surfactant, are essential to proper respiratory function in that they lower the surface tension of the alveoli. They are also important components of the innate immune system. The functional significance of these proteins is currently reflected by a very large and growing number of publications. The objective goal of this study was to elucidate whether Staphylococcus aureus and Pseudomonas aeruginosa is able to express surfactant proteins. 10 different strains of S. aureus and P. aeruginosa were analyzed by means of RT-PCR, Western blot analysis, ELISA, immunofluorescence microscopy and immunoelectron microscopy. The unexpected and surprising finding revealed in this study is that different strains of S. aureus and P. aeruginosa express and secrete proteins that react with currently commercially available antibodies to known human surfactant proteins. Our results strongly suggest that the bacteria are either able to express ‘human-like’ surfactant proteins on their own or that commercially available primers and antibodies to human surfactant proteins detect identical bacterial proteins and genes. The results may reflect the existence of a new group of bacterial surfactant proteins and DNA currently lacking in the relevant sequence and structure databases. At any rate, our knowledge of human surfactant proteins obtained from immunological and molecular biological studies may have been falsified by the presence of bacterial proteins and DNA and therefore requires critical reassessment

Effect of Disinfectants on Mechanical Properties of Orthodontic Acrylics

Objective. Infection control protocols in dentistry dictate that orthodontic acrylics have to be disinfected. No specific products for orthodontic acrylics are available. The objective of this study was to investigate the influence of chemical disinfectants on mechanical properties of orthodontic acrylics. Materials and Methods. 260 test specimens of two cold-curing orthodontic acrylics were manufactured. Three chemical disinfecting agents were tested: Impresept, D050 Instru-Gen, and Stammopur DR. Test specimens were stored in distilled water and divided into test groups. E-Modulus, flexural strength, macro hardness, micro hardness, average roughness, and colour change were measured. Results. Disinfection agents showed no significant influence on E-modulus. Values ranged from 1783.80 ± 163.80 MPa (Forestacryl colourless) to 2474.00 ± 135.00 MPa (Orthocryl green) after storage in distilled water. Disinfection agents performed no significant influence on flexural strength. Values ranged from 18.64±1.59 N/mm2 (Forestacryl colourless) to 25.64 ± 1.43 N/mm2 (Orthocryl green) after storage in distilled water. Orthocryl colourless showed a reduction of the macro hardness after disinfection (Stammopur DR (p≤0.001), D050 Instru-Gen (p≤0.037)). Disinfection of Orthocryl green with D050 Instru-Gen (p<0.001) and Forestacryl colourless with Impresept (p≤0.001) led to a reduction of macro hardness. Micro hardness of Orthocryl colourless altered significantly after disinfection with D050 Instru-Gen (p≤0.001). Micro hardness of Forestacryl colourless increased (Impresept (p≤0.039)) and decreased (Stammopur DR (p≤0.006) Instru-Gen (p≤0.001)) after disinfection. Average roughness did not change significantly (Orthocryl colourless). Forestacryl colourless performed a significant change after disinfection with Stammopur DR (p≤0.05). This is also true for the disinfection of Orthocryl green and Forestacryl pink with Instru-Gen (p≤0.05). Disinfection performed no significant influence on colour change. ΔE-values were in a range of 1 to 2. Conclusions. Some orthodontic acrylics disinfection caused significant changes of determined parameters. Changes were specific for the applied disinfectant and tested orthodontic acrylic. Further studies should verify the impact of long-term disinfection intervals. Thus, from manufacturers of orthodontic acrylics recommendations for appropriate disinfectants would be desirable

Bacterial strains used in this study.

<p>Bacterial strains used in this study.</p

PCR and RT-PCR analysis of bacterial strains.

<p><b>A</b>) RT–PCR analysis for transcripts encoding surfactant proteins (A, B, C, D) from <i>S. aureus</i> displaying the samples from different strains; 1. SA 113 [ATCC 35556] aerobe, 2. SA 113 [ATCC 35556] anaerobe, 3. SA N315 [ATCC 12228] aerobe, 4. SA [NCTC 8325] aerobe. <b>B</b>) RT–PCR analysis for transcripts encoding surfactant proteins (A, B, C, D) from <i>P. aeruginosa</i> displaying the samples from different strains; 1. PA 01 aerobe, 2. PA 01 anaerobe, 3. PA [ATCC 14442] aerobe, 4. PA [ATCC 27853] aerobe. <b>C</b>) PCR analysis for genomic DNA from <i>S. aureus</i> and <i>P. aeruginosa</i> displaying the samples from different strains; 1. PA 01 Laboratory strain; 2. PA 154 Environmental isolate, 3. PA (12) Patient isolate, 4. SA 113 [ATCC 35556] Laboratory strain, 5. SA (8) Patient isolate, 6. SA (16) Patient isolate. <b>D</b>) PCR analysis of bacterial DNA from (1) <i>E. coli</i> BL21 (no plasmid) and from (2) <i>E. coli</i> [ATCC 35218] (plasmid). In each case a (RT-)PCR using ß-actin (human), GyrA (bacterial) was performed to include/exclude bacterial/human contamination. (+) indicates the internal positive control for the PCR experiments. E) PCR analysis of bacterial DNA from (1) <i>Pyrococcus furiosus</i> that serves as negative control.</p

ELISA quantification of surfactant proteins A, B, C and D in <i>S. aureus</i> (A) and <i>P. aeruginosa</i> (B).

<p>ELISA quantification of SP-A, -B, -C and –D in <i>S. aureus</i> (A) and <i>P. aeruginosa</i> (B) after cultivation using different media conditions (aerobic and anaerobic). For <i>S. aureus</i> (A) the concentration of each surfactant proteins is significantly increased in case of anaerobic cultivation (significance in p is shown in the figure for each surfactant protein. <i>P. aeruginosa</i> also reveals a rise in protein concentration after anaerobic cultivation, but this is not significant.</p

Sequences of the primers used for detection of surfactant proteins (A; B; C; D), RT-PCR analysis.

<p>Sequences of the primers used for detection of surfactant proteins (A; B; C; D), RT-PCR analysis.</p