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.

Cumulative 10-year performance of endodontically treated teeth with prosthetic restorations of base metal alloy double crowns with friction pins-a retrospective study.

OBJECTIVES: This 120-month follow-up study aimed to investigate the complication rate of abutment teeth after endodontic pretreatment with base metal alloy double crowns with friction pins. MATERIALS AND METHODS: A total of 158 participants (n = 71, 44.9% women) aged 62.5 ± 12.7 years with 182 prostheses on 520 abutment teeth (n = 459, 88.3% vital) were retrospectively analyzed between 2006 and 2022. Of the endodontically treated abutment teeth, 6.9% (n = 36) were additionally treated with post and core reconstructions. Cumulative complication rates were calculated using the Kaplan-Meier estimator and log-rank test. In addition, Cox regression analysis was performed. RESULTS: The cumulative complication rate at 120 months for the entire set of abutment teeth was 39.6% (confidence interval [CI]: 33.0-46.2). Endodontically treated abutment teeth (33.8%; CI: 19.6-48.0) were found to have a significantly higher cumulative fracture rate than vital teeth (19.9%; CI: 13.9-25.9, p < 0.001). Endodontically treated teeth restored with post and core reconstructions (30.4%; CI: 13.2-47.6) showed a nonsignificant lower cumulative fracture rate than that of teeth with root fillings only (41.6%; CI: 16.4-66.8, p = 0.463). CONCLUSIONS: Higher 120-month cumulative fracture rates were observed in endodontically treated teeth. Comparable performance was observed in teeth with post and core reconstructions compared to teeth with root fillings only. CLINICAL RELEVANCE: If endodontically treated teeth are used as abutments for double crowns, the risk of complications from these teeth should be considered when planning treatment and communicating with the patient.

Ten-year clinical performance of non-precious metal double crowns with friction pins in severely reduced dentitions-a retrospective study.

OBJECTIVES: This follow-up study aimed at collecting long-term data for removable partial dentures (RPDs) retained by double crowns with spark-eroded friction pins (DCP) and comparing them in the presence of severely reduced dentition (SRD) and non-SRD (NSRD, i.e. residual dentition with more than three abutment teeth) after a 10-year wearing period. MATERIALS AND METHODS: A total of 158 participants (n = 71, 44.9% women) aged 62.5 ± 12.7 years with 182 prostheses on 520 abutment teeth were followed up between 2006 and 2022. The SRD group included 144 RPDs supported by 314 abutment teeth. The data collection was performed retrospectively. 10-year survival rates of RPDs and abutment teeth were determined using the Kaplan-Meier method and compared using the log-rank test for SRD and NSRD, among others. Cox regression analyses were conducted to isolate risk factors for the survival of both RPDs and abutment teeth. RESULTS: The 10-year cumulative survival rate of all abutment teeth was 65.6% with significantly lower values in the SRD group (53.5%) (p < 0.001). The survival rate for all RPDs was 65.5%. The SRD group showed lower survival rates (57.9%) (p = 0.004). The number and location of the abutment teeth had a significant influence on the survival rates of the RPDs and the abutment teeth. Age, sex, jaw, relining, and vitality had a significant influence on the abutment teeth survival rates. CONCLUSIONS: RPDs showed an acceptable clinical survival rate after 10 years. The number, location, and vitality of abutment teeth were factors that influenced the survival of both RPDs and abutment teeth. CLINICAL RELEVANCE: Consideration of the influencing factors found can help improve the prognostic assessment of double crown-retained dentures in the context of prosthetic therapy planning.

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.

Oral health status of nursing staff in Ilembula, Wanging'ombe District, Njombe region, Tanzania: a cross-sectional study.

BACKGROUND: Owing to the reduced dental treatment infrastructure in the Tanzanian highlands, maintaining good oral health is a challenge for not only the general population but also individual professional groups. In this study, the caries prevalence and, subsequently, the prosthetic treatment needs of the nurses of the Ilembula Lutheran Hospital (ILH) and Ilembula Institute of Health and Allied Sciences (IIHAS), Tanzania, were investigated. MATERIALS AND METHODS: One hundred and sixty-eight ILH and IIHAS nurses and nursing students (87 women, 81 men; age 23.1 ± 6.1 years, range 18-58 years) participated in this cross-sectional study conducted in February 2020. The participants were examined at the dental office of ILH. The Decayed, Missing, and Filled Teeth (DMF/T) Index, Simplified Oral Hygiene Index, and details regarding edentulism, nutrition habits, and socioeconomic factors were collected. Linear regression and binary logistic regression were used for statistical analysis. RESULTS: The mean DMF/T-Index was 6.30 ± 4.52. In 7.14% of the investigated nurses, no dental plaque was detected. An enhanced prosthodontic treatment (Kennedy Class III) demand was identified in 31.50% of the participants, and 4.80% of the participants required treatment for acute malocclusion. Oral hygiene products were used by 99.4% of the patients. CONCLUSIONS: The current oral health situation of the study participants showed a moderate restorative and prosthetic treatment demand in the rural area of Tanzania. The development of an interdisciplinary oral health prophylaxis system could be a means to remedy this situation.

Impact of the Veneering Technique and Framework Material on the Failure Loads of All-Ceramic Computer-Aided Design/Computer-Aided Manufacturing Fixed Partial Dentures.

OBJECTIVES: Zirconia (Y-TZP) ceramics are considered as posterior fixed partial denture (FPD) materials; however, their applications are limited due to chipping. The use of monolithic lithium disilicate (LiDi) glass ceramics in posterior FPDs can be advantageous. This in vitro study aims to compare the loads until failure of posterior Y-TZP-FPDs and LiDi-FPDs before and after aging.

The Oral Health Situation of 12-Year-Old School Children in the Rural Region of Ilembula in Southwestern Tanzania: A Cross-Sectional Study.

There has been no research on the prevalence of and factors associated with dental caries in rural southwestern Tanzania among schoolchildren. Determining the prevalence of and factors associated with dental caries will help to assess the need for dental intervention and prophylactic measures among children in the region. In February 2020, a cross-sectional study was conducted in the Wanging'ombe District of the Ilembula Ward. The data were collected through clinical examinations and personal interviews at two primary schools. Univariable and multivariable logistic regression analyses were performed to identify potential risk indicators for caries. The study included 319 students aged 11-12 years (average 11.92 ± 0.27 years). The mean Decayed, Missing and Filled Teeth index was 0.24 ± 0.68, and the mean Specific affected Caries Index was 1.66 ± 0.9. The greatest influences on the caries risk were poor oral hygiene (OR 8.05, 95% CI 0.49-133.23), low tooth brushing frequency (OR 3.03, 95% CI 1.26-7.26) and low level of education in parents (OR 2.63, 95% CI 0.99-6.98). Dental caries was low among students in rural areas in the Wanging'ombe District.

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.

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.

Single crowns with CAD/CAM-fabricated copings from titanium: 6-year clinical results.

STATEMENT OF PROBLEM: Computer-aided design/computer-aided manufacturing (CAD/CAM) titanium ceramic restorations were developed with the potential for replacing expensive, high noble metal ceramic restorations. However, little information exists about the clinical performance of CAD/CAM titanium ceramic single crowns. PURPOSE: The purpose of this study was to evaluate CAD/CAM titanium ceramic single crowns after 6 years in function. MATERIAL AND METHODS: A total of 41 crowns were fabricated for 21 patients. The titanium copings were CAD/CAM milled (Everest CAD/CAM system), with an even thickness of 0.5 mm and veneered with low-fusing porcelain (Vita Titanium Porcelain) in the powder-build-up technique. All the crowns were cemented with zinc phosphate. The participants were recalled at 12, 24, 36, 48, 60, and 72 months after cementation to document any mechanical and biologic complications and to measure the periodontal parameters, such as probing depth, bleeding on probing, and the plaque index. The success and survival rates were calculated according to the Kaplan-Meier analysis. RESULTS: After 6 years of clinical service, 12 mechanical complications and 1 biologic complication were found, which resulted in a success rate of 67.8%. The cumulative survival rate of the crowns was 91.3% after 6 years. At the end of the follow-up period, the probing depth was 3.21 mm, the percentile of surface with bleeding on probing was 25, and the plaque index was 0.37. No secondary caries or decementation was detected during the 6-year observation period. CONCLUSIONS: The clinical performance of the CAD/CAM titanium-ceramic crowns after 6 years was poor because of veneering porcelain problems. Recent CAD software with tools to design proper copings might improve the clinical success.

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.

Disinfection effect of dental impression tray adhesives.

OBJECTIVES: Iatrogenic infections are serious problems in dental offices. Impression tray adhesives are delivered in glass containers with a fixed brush attached inside the cap. Using the brush for application of the impression tray adhesive on a contaminated impression tray or prostheses, pathogen transmission by replacing the cap with the brush is possible. MATERIALS AND METHODS: Bacterial strains (patient strains and in vitro strains) were supervaccinated on Columbia agar. The bacterial solution was diluted with TSB and aerobically grown, and starting concentration was 1 × 10(7) cfu/ml. The stock solution was placed on Columbia agar. Alginate, polyether, and silicon impression tray adhesives were applied to the center of the particular blood agar plates and incubated for 48 h. The expansion of the inhibition zone assays were measured using a microscope. RESULTS: Twenty-one different bacterial strains were selected in the saliva samples of 20 patients. The growth inhibition for alginate impression tray adhesive was 1.1 % (±0.3) of the patient strains. The overgrowth of polyether impression tray adhesive was 30.6 % (±9.3) and for silicon impression tray adhesive 11.8 % (±5.0). In in vitro strains, alginate impression tray adhesive performed an inhibition of 0.7 % (±0.3). The overgrowth of polyether impression tray adhesive was 7.0 % (±1.6) and for silicon impression tray adhesive was 6.5 % (±1.3). CONCLUSIONS: Using the fixed brush for application of the impression tray adhesive on multiple patients, a cross-contamination cannot be ruled out. CLINICAL RELEVANCE: An application of the impression tray adhesive with a pipette and a single-use brush would eliminate the contamination.

Metal-ceramic-fixed dental prosthesis with CAD/CAM-fabricated substructures: 6-year clinical results.

OBJECTIVES: The aim of this study was to evaluate the clinical performance of fixed dental prostheses (FDPs) with computer-aided design (CAD)/computer-aided manufacturing (CAM)-fabricated titanium substructures veneered with low-fusing porcelain after 6 years. MATERIALS AND METHODS: Thirty-one FDPs for 23 patients were fabricated. The frameworks were designed and milled using an early version of a dental CAD/CAM system. Checkups were performed annually. RESULTS: Complications totaled ten porcelain fractures, one substructure fracture, and one biologic failure. The success rate was calculated at 58.6 % and the survival rate at 88 % (Kaplan-Meier analysis). CONCLUSION: The clinical performance of the described technique for FDPs with titanium substructures was poor. Therefore, the presented concept cannot be recommended. CLINICAL RELEVANCE: CAD/CAM-fabricated titanium substructures veneered with the powder build-up technique showed poor clinical outcome after 6 years.

Lactate in cystic fibrosis sputum.

BACKGROUND: Antibiotic therapy is thought to improve lung function in patients with cystic fibrosis (CF) by decreasing neutrophil-derived inflammation. We investigated the origin and clinical significance of lactate in the chronically inflamed CF lung. METHODS: Lactate was measured in sputa of 18 exacerbated and 25 stable CF patients via spectrophotometry and gaschromatography. Lung function was assessed via spirometry. Seven patients with chronic obstructive pulmonary disease (COPD) and three patients with acute lung inflammation served as control groups. Neutrophil and bacterial lactate production was assessed under aerobic and anaerobic conditions. RESULTS: In sputum specimens of patients with respiratory exacerbations lactate concentrations decreased significantly (p<0.005) from 3.4±2.3mmol/L to 1.4±1.4mmol/L after 2-3 weeks of intravenous antibiotics. Successful treatment was reflected in 16 patients (88.9%) by FVC increase associated with lactate decrease (p<0.05). In every single sputum lactate was detectable (3.0±3.1mmol/L, range 0.2-14.1mmol/L). Lactate was lower (1.6±0.8mmol/L) in sputa from seven COPD patients, and it was below the detection limit in three patients with acute lung inflammation. Neutrophil lactate production accumulated up to 10.5mmol/L after 4 days, whereas bacterial lactate production did not appear to contribute substantially to sputum lactate concentrations. CONCLUSIONS: Successful antibiotic therapy is reflected by a decrease in lactate concentrations. Neutrophils are the most likely source for lactate in sputum of CF patients. Therefore lactate may be used to monitor responses to antibiotic therapy as an adjunct to lung function measurements.