Bacterial contamination potential of personal protective equipment itself in dental aerosol-producing treatments.

Personal protective equipment (PPE) has long been a high priority in dental aerosol-producing treatments. Since COVID-19 pandemic, its importance has increased yet again. While importance of PPE in preventing transmission and thus possible infection of pathogens is well known, contamination potential of PPE after treatment itself is less investigated. This review aims to give an overview of the current literature and contamination potential (viral, blood, bacterial) of components of protective equipment itself. The literature search was performed using the Medline database; furthermore, a hand search was conducted. Last search took place on 23 November 2022. Two categories of hygiene-related keywords were formed (category A: mask, face shield, goggles, eyewear, personal protective equipment; category B: contamination, aerosol). Each keyword from one category was combined with all keywords from the other one. In addition, the keyword "dental" was always added. First, a title and abstract screening was performed. Afterward, a full-text analysis was followed for the included studies. A total of 648 search hits were found in the Medline database. 47 were included after title and abstract screening. 22 studies were excluded after full-text analysis, 25 studies were included. The hand search resulted in 4 studies that were included. Bacterial contamination of PPE after treatment has been adequately studied, contamination with blood less. Microorganisms mainly originate from the oral and cutaneous flora; however, a transmission of potential pathogens like Staphylococcus aureus or Escherichia coli was also described. Studies showing transmission pathways starting from PPE and its various components are lacking. No measures have yet been described that fully protect the protective equipment from contamination. There is growing awareness that PPE itself can be a source of pathogen transmission, and thus possible infection. Therefore, not only wearing of protective clothing, but also conscious handling of it is crucial for transmission and possible infection prevention. However, studies showing transmission pathways starting from PPE and its various components are lacking. Several studies have investigated what measures can be taken to protect the protective equipment itself. So far, none of the methods evaluated can prevent contamination of PPE.

Dental aerosol-producing treatments: Comparison of contamination patterns of face shields and surgical masks.

During the COVID-19 pandemic, dental face shields were recommended to protect the eyes. This study aimed to examine to what extent face shield and mask contamination differ when a pre-procedural mouth rinsing with Chlorhexidine (CHX) is conducted before treatment. In this prospective, randomized study, three groups of subjects were formed (rinsing with 0.1% CHX, water, or no rinsing (control) before aerosol-producing treatments). After each of the 301 treatments, the practitioner's face shield was swabbed with eSwab and the mask was brought into contact with agar plates. Sampling was done from the exterior surface only. Samples were cultured for 48 h at 35 °C under aerobic and anaerobic conditions. Bacteria were classified by phenotypic characteristics, biochemical test methods, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Colony-forming units were counted and mean values were compared (WSR, H-test, U-test, p < 0.05). Within each subject group, face shields showed significantly more contamination than surgical masks (control group: 350 CFU, 50 CFU; intervention water: 270 CFU, 40 CFU; intervention CHX: 250 CFU, 30 CFU). Comparison of face shields of the different subject groups did not reveal any statistically significant differences. However, CHX resulted in a statistically significant bacterial reduction on surgical masks compared to the water and control group (control: 50 CFU, intervention water: 40 CFU, intervention CHX: 30 CFU). Contamination of face shields and surgical masks was highest in the control group, followed by the water group, and lowest in the intervention group with CHX. Streptococcus spp. and Staphylococcus spp. dominated, representing the oral and cutaneous flora. Contamination of masks worn with or without face shields did not differ. Presumably, face shields intercept first splashes and droplets, while the masks were mainly exposed to bioaerosol mist. Consequently, face shields protect the facial region and surroundings from splashes and droplets, but not the mask itself. A pre-procedural mouth rinse with CHX had no statistically significant reducing effect on contamination of the face shield, but a statistically significant reducing effect was observed on contamination of the mask.

The impact of general medical health status, demographical, and patient-specific variables on need for dental treatment of children and adolescents under general anesthesia.

OBJECTIVES: Aim of this retrospective study was to examine the influence of general medical, demographical, and other patient-specific factors on the need for dental treatment under general anesthesia in children and adolescents at Saarland University Hospital. For assessment of the clinical treatment need, a mixed dt/DT (decayed teeth) was introduced. MATERIALS AND METHODS: A total of 340 patients under 18 years of age who received restorative-surgical dental treatment between 2011 and 2022 were anonymously enrolled. Demographic and other patient-specific data, general medical health, oral health, and treatment related data were recorded. In addition to descriptive analysis, Spearman-Rho-test, Mann-Whitney-U-test, Kruskall-Wallis-test and Chi-square-test were used. RESULTS: More than half of the patients (52,6%) were in general health, but non-cooperative. The majority of the patients (66.8%) was between 1 and 5 years of age (p < 0,001). Mean dmft was 10.95 ± 4.118, mean DMFT was 10.09 ± 7.885, and mean dt/DT was 10.79 ± 4.273. Analysis showed that communication difficulties significantly influenced dmft (p = 0.004), DMFT (p = 0.019), and dt/DT (p < 0.001). Type of insurance significantly affected dmft (p = 0.004) and dt/DT (p = 0.001). There was no significant effect of ASA on caries experience, however on prevalence of severe gingivitis (p < 0.001), number of extractions (p = 0.002), and need for repeated treatment (p < 0.001). CONCLUSIONS: Need for dental treatment in the present collective was high, independent of the considered variables. Non-Cooperativeness along with ECC was the main indication for dental general anesthesia. The mixed dt/DT was the most precise survey to evaluate clinical treatment needs. CLINICAL RELEVANCE: Given the enormous demand for these rehabilitations with strict selection, it is imperative to create more treatment capacities for patients mandatorily requiring general anesthesia by avoiding it in healthy patients.

[Introduction of "professional field exploration" for Saarland University dentistry students]. / Einführung des Fachs "Berufsfelderkundung" für Studierende der Zahnmedizin an der Universität des Saarlandes.

The new dental licensing regulations (ZApprO) have been in effect since the 2021/2022 winter semester and stipulate that a "professional field exploration course" be offered in the dentistry degree program. At Saarland University, the course consists of five parts: (I) introduction, (II) practicum, (III) reflection report, (IV) symposium, and (V) evaluation. The practicum is designed to provide students with earlier exposure to clinical reality, give them more confidence in dealing with patients, motivate them, and teach them about the professional role in the healthcare profession. In addition, the reflection report and symposium will initiate the development of scientific competencies. The evaluation, together with the evaluation of the reflection reports, serves to verify the success of the introduction of the course. The purpose of this paper is to describe the new course and to present the results of the result of the evaluation of the two courses in 2021 and 2022.

Expression of inflammatory mediators in biofilm samples and clinical association in inflammatory bowel disease patients-a preliminary study.

OBJECTIVES: Inflammatory bowel disease (IBD) has multiple impacts on soft and hard tissues in the oral cavity. The aim of this study was to analyze the expression of cytokines in biofilm samples from patients suffering from IBD and compare them to healthy patients. It was hypothesized that different cytokine expression levels and clinical associations might be drawn. MATERIAL AND METHODS: A total of 56 biofilm samples from three different patient cohorts (group 0 = healthy, HC n = 30; group 1 = Crohn's disease, CD, n = 19; group 2 = ulcerative colitis, UC, n = 7) were examined for the expression levels of the cytokine interleukins IL-2, -6, and -10; matrix metalloproteinases 7 and 9; and surface antigens CD90/CD11a by quantitative real-time PCR and according to clinical parameters (plaque index, BOP, PD, DMFT, CAL). Relative gene expression was determined using the ∆∆CT method. RESULTS: The mean BOP values (p = 0.001) and PD (p = 0.000) were significantly higher in the CD group compared to controls. Expression of IL-10 was significantly higher in the CD (p = 0.004) and UC groups (p = 0.022). Expression of MMP-7 was significantly higher in the CD group (p = 0.032). IBD patients treated with TNF inhibitors (p = 0.007) or other immunosuppressants (p = 0.014) showed significant overexpression of IL-10 compared to controls. CONCLUSION: Different expression levels of IL-10 and MMP-7 were detected in plaque samples from IBD patients. As only BOP was significantly increased, we conclude that no clinical impairment of periodontal tissue occurred in IBD patients. CLINICAL RELEVANCE: With the worldwide increasing incidence of IBD, it is important to obtain insights into the effects of the disease on the oral cavity. The study was registered (01.09.2020) at the German clinical trial registry (DRKS00022956). CLINICAL TRIAL REGISTRATION: The study is registered at the German clinical trial registry (DRKS00022956).

Apical periodontitis after intense bruxism.

BACKGROUND: Bruxism is known to cause masticatory muscle pain, temporomandibular joint pain, headaches, mechanical tooth wear, prosthodontic complications and cracked teeth. Less known to the practitioner, and described only experimentally in literature, is that bruxism can also damage the pulp. To our knowledge, this is the first known clinical case of a patient developing apical periodontitis due to bruxism. CASE PRESENTATION: This article presents the case and successful treatment of a 28-year-old healthy male patient with apical periodontitis on teeth 36 and 46 requiring root canal treatment after an intense phase of bruxism. Due to an unclear diagnosis, treatment had been delayed. CONCLUSIONS: Incomprehensible tooth pain can be the result of bruxism. Practitioners need to be informed that intense bruxism can possibly lead to apical periodontitis. It is important, therefore, that a thorough anamnesis is collected and taken into account during diagnostics.

Contamination of surgical mask during aerosol-producing dental treatments.

OBJECTIVES: Surgical masks are usually contaminated during dental treatment. So far it has not been investigated whether a surgical mask itself can be a source of microbial transmission. The aim of this study was therefore to investigate the microbiological contamination of surgical masks during dental treatment and the transfer of microorganisms from the mask to the hands. MATERIALS AND METHODS: Five dental treatment modalities were studied: carious cavity preparation (P-caries, n = 10), tooth substance preparation (P-tooth, n = 10), trepanation and root canal treatment (P-endo, n = 10), supragingival ultrasonic application (US-supra, n = 10), and subgingival periodontal ultrasonic instrumentation (US-sub, n = 10). Bacterial contamination of mask and gloves worn during treatment was tested by imprinting on agar plates. Additionally, before masks were tested, their outer surface was touched with a new sterile glove. This glove was also imprinted on agar. Bacteria were identified by MALDI TOF mass spectrometry. Colony-forming units (CFU) were scored: score 0: 0 CFU, score 1: < 102 CFU, score 2: > 102 CFU, score 3: dense microbial growth. RESULTS: All masks and all gloves used during treatment displayed bacterial contamination (sample scores 0/1/2/3: masks 0/46/3/1 and gloves 0/31/10/9). After touching the masks with new sterile gloves, microorganisms were recovered with the following contamination scores: P-caries: 4/6/0/0, P-tooth: 2/8/0/0: P-endo: 7/3/0/0, US-supra: 0/9/1/0, US-sub: 2/8/0/0. No statistically significant differences were detected between the treatment modalities. Streptococci spp. and Staphylococci spp. representing the oral and cutaneous flora dominated. CONCLUSIONS: Surgical masks are contaminated after aerosol-producing dental treatment procedures. Used masks have a potential to be a source of bacterial contamination of the hands. CLINICAL RELEVANCE: Dental staff should avoid touching the outer surface of masks with their hands to prevent transmission of pathogens. It is recommendable to change the mask after each treated patient followed by hand disinfection.

Detection of viable oral bacteria of the patient on the surgical mask of dentists.

INTRODUCTION AND AIM: Bioaerosols contaminate the personal protective equipment (PPE), especially masks. The PPE harbors microorganisms from various sources. However, no previous studies have investigated the specific sources of bacteria found on used masks and their correlation with those from the treated patient. SETTING, DESIGN, MATERIAL AND METHODS: Intraoral samples from the patient were collected prior to dental aerosol-producing treatments using a nylon flock fiber swab. After treatment, the practitioner's mask was imprinted onto agar plates. MAIN OUTCOME METHODS: Following cultivation, colony forming units were counted and identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). After the samples were analyzed, the intraoral samples as well as the mask samples were assessed for the presence of identical species, which were subsequently quantified. RESULTS: 126 treatments were included. One species match occurred most frequently (26.2%), followed by two (11.9%%) and three or more (3.97%). In the intraoral samples, Neisseria subflava occurred most often, within mask samples Staphylococcus epidermidis were detected most. Staphylococcus aureus could be cultivated three times more often in intraoral samples than on the mask. DISCUSSION AND CONCLUSION: Oral microorganisms originating from the patient's oral cavity can be found on the outside of masks. When using PPE during treatments, it should therefore always be in mind that potentially pathogenic microorganisms may land on the mask becoming a source of for itself.

L. reuteri in Supportive Periodontal Therapy-Are There Already Clinical Effects after 3 Months with One Lozenge a Day? A Double-Blind Randomized Placebo-Controlled Study.

AIM: The purpose of this study was to investigate whether a clinical effect of Lactobacillus reuteri in supportive periodontal therapy can already be detected with a minimum dose of one tablet a day and a minimum observation and intake period of 3 months. MATERIALS AND METHODS: 28 patients with stage III and IV periodontitis undergoing periodontal follow-up were randomly divided into two groups receiving a lozenge containing L. reuteri or a placebo preparation daily for 90 days. After 0, 4, 8, and 12 weeks, the parameters bleeding on probing (BoP), plaque control record (PCR), periodontal probing depth (PPD), and clinical attachment level (CAL) were recorded in the test and control groups. RESULTS: The results sed a different effect of L. reuteri on the respective patients. In certain patients, clinical parameters worsened or remained largely unchanged. However, in other patients, there were positive effects on the clinical parameters. In the overall analysis, BoP was the only clinical parameter that was statistically significantly reduced. CONCLUSIONS: The oral administration of one lozenge per day for 3 months with L. reuteri in supportive periodontal therapy might have a positive influence on clinical parameters in supportive periodontal therapy, depending on the individual.

Cold Atmospheric Plasma Improves the Colonization of Titanium with Primary Human Osteoblasts: An In Vitro Study.

Several studies have shown that cold atmospheric plasma (CAP) treatment can favourably modify titanium surfaces to promote osteoblast colonization. The aim of this study was to investigate the initial attachment of primary human osteoblasts to plasma-treated titanium. Micro-structured titanium discs were treated with cold atmospheric plasma followed by the application of primary human osteoblasts. The microwave plasma source used in this study uses helium as a carrier gas and was developed at the Leibniz Institute for Surface Modification in Leipzig, Germany. Primary human osteoblasts were analyzed by fluorescence and cell biological tests (alkaline phosphatase activity and cell proliferation using WST-1 assay). The tests were performed after 4, 12, and 24 h and showed statistically significant increased levels of cell activity after plasma treatment. The results of this study indicate that plasma treatment improves the initial attachment of primary human osteoblasts to titanium. For the first time, the positive effect of cold atmospheric plasma treatment of micro-structured titanium on the initial colonization with primary human osteoblasts has been demonstrated. Overall, this study demonstrates the excellent biocompatibility of micro-structured titanium. The results of this study support efforts to use cold atmospheric plasmas in implantology, both for preimplantation conditioning and for regeneration of lost attachment due to peri-implantitis.

Effects of Cold Atmospheric Plasma Pre-Treatment of Titanium on the Biological Activity of Primary Human Gingival Fibroblasts.

Cold atmospheric plasma treatment (CAP) enables the contactless modification of titanium. This study aimed to investigate the attachment of primary human gingival fibroblasts on titanium. Machined and microstructured titanium discs were exposed to cold atmospheric plasma, followed by the application of primary human gingival fibroblasts onto the disc. The fibroblast cultures were analyzed by fluorescence, scanning electron microscopy and cell-biological tests. The treated titanium displayed a more homogeneous and denser fibroblast coverage, while its biological behavior was not altered. This study demonstrated for the first time the beneficial effect of CAP treatment on the initial attachment of primary human gingival fibroblasts on titanium. The results support the application of CAP in the context of pre-implantation conditioning, as well as of peri-implant disease treatment.

Nutritional and Oral Hygiene Knowledge versus Reported Behavior of Children and Adolescents-A Cross-Sectional Interview-Based Study.

Despite the fact that healthy, sugar-reduced nutrition has been propagated by the media and in schools for years, dental caries in children remains a major health problem worldwide, caused primarily by an unhealthy diet. The objective of this study is to compare statements on nutrition and hygienic knowledge with those on children's actual dietary and hygienic behavior. A random sample of 554 children and adolescents aged 3-19 years was enrolled. Designed as a cross-sectional interview-based community survey, this study was conducted consecutively during three one-day public science-promoting events at the Saarland University's Medical Faculty. Participants' oral hygiene and nutritional knowledge was profound; however, the reported translation into practice showed deficiencies. Boys and younger children (3-10 years) often showed better oral hygiene knowledge than girls and older children (over 11 years) but had problems implementing it into their daily life practice. In contrast, girls and older children often showed less oral hygiene knowledge but reported more favorable behavior. Finally, children up to the mixed dentition phase preferred drinking sweets more often than older children, posing a risk to the developing permanent dentition. Intensifying well-known controlled motivation training approaches to encourage children and adolescents is recommended to put their knowledge into practice.

CHX and a Face Shield Cannot Prevent Contamination of Surgical Masks.

Background: Bacterial contamination on surgical masks puts a threat to medical staff and patients. The aim of the study was to investigate its contamination during dental treatments, wearing a face shield and performing a pre-procedural mouth rinsing with chlorhexidine (CHX). Methods: In this prospective, randomized study, 306 treatments were included, 141 single-tooth (restorations) and 165 total dentition treatments (preventive or periodontal supportive ultrasonic application). A total of three groups (each: n = 102) were formed: participants rinsed for 60 s with 0.1 % CHX or with water before treatment, and, for control, a non-rinsing group was included. In view of the COVID-19 pandemic, a face shield covering the surgical mask enhanced personal protective equipment. After treatment, masks were imprinted on agar plates and incubated at 35°C for 48 h. Bacteria were classified by phenotypic characteristics, biochemical assay methods, and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Colonies (CFU) were counted and mean values were compared (Kruskal-Wallis-, U test, p < 0.05). Results: Chlorhexidine led to a statistically significant reduction of bacterial contamination of the surgical mask (mean: 24 CFU) in comparison with water (mean: 47 CFU) and non-rinsing (mean: 80 CFU). Furthermore, rinsing with water reduced CFU significantly in comparison with the non-rinsing group. There were no significant differences between single or total dentition treatments. Streptococcus spp., Staphylococcus spp., Micrococcus spp., and Bacillus spp. dominated, representing the oral and cutaneous flora. Conclusion: A pre-procedural mouth rinse is useful to reduce the bacterial load of the surgical mask. However, contamination cannot be prevented completely, even by applying a face shield. In particular, during pandemic, it is important to consider that these additional protective measures are not able to completely avoid the transmission of pathogens bearing aerosols to the facial region. If antiseptic rinsing solutions are not available, rinsing with water is also useful.

Oral hygiene knowledge versus behavior in children: A questionnaire-based, interview-style analysis and on-site assessment of toothbrushing practices.

OBJECTIVES: Oral hygiene plays an important role in eliminating biofilms and preventing dental caries. However, the implementation of oral health knowledge that children learn from their parents and through school dental health programmes remains poorly studied. This study aimed to investigate oral hygiene knowledge and its practical utilization in children and young adolescents (CYAs) aged 2-15 years. MATERIAL AND METHODS: This was a questionnaire-based, interview-style community survey and on-site practical assessment of CYAs' toothbrushing skills conducted during two 1-day public science-promoting events held at a major German university hospital in consecutive years. CYAs first answered questions on toothbrushing frequency, dental aids used, and dental care. They subsequently underwent diagnostic staining and demonstrated their brushing technique and method. CYAs' responses (percentages) to questionnaire items addressing oral hygiene knowledge and practice, and on-site assessment of toothbrushing skills served as the main outcome measures. RESULTS: Of 244 participating CYAs, 178 (73%) CYAs had no caries experience, the percentage increasing with age from 5% in 2-5-year-olds to 40% in those aged > 10 years. Of 117/244 (48%) indicating that teeth should be brushed three times daily, 80/117 (68%) self-reported twice-daily brushing, 32/117 (27%) reported brushing three times, and 4/117 (3%) stated doing so only once. Although 131/244 (54%) considered that teeth should be brushed for 3 min, 77/131 (59%) self-reported actually doing so and 41/131 (31%) reported brushing for 2min. Seventeen of 42 (40%) participants aged > 10 years showed no systematic brushing method, with 21/42 (50%) failing to clean their teeth completely. Participants aged 6-10 years exhibited the highest proportion (97/134, 72%) of complete cleaning. One hundred and forty-six of 244 (60%) of CYAs knew about floss; 63/134 (43%) reported using it. Good adherence to oral health recommendations (i.e., brushing ≥ 2/day for ≥2min) was observed in 212/244 (87%) CYAs, the remaining 32/244 (13%) exhibiting poor adherence. CONCLUSION: CYAs knew about the importance of oral hygiene and cleaned their teeth frequently. However, translation of their knowledge into practice showed deficiencies. Repeated encouragement to put oral health knowledge into practice is important.

Bacterial contamination of forehead skin and surgical mask in aerosol-producing dental treatment.

BACKGROUND: Bacterial contamination of dental professionals' facial skin and protective equipment from treatment-related aerosols and droplets are poorly studied. METHODS: This prospective study analyzed samples from 67 consecutive aerosol-producing dental treatments. Sterile nylon swabs served to collect samples from dental professionals' foreheads before and after exposure. Contact samples were obtained from used surgical masks. Samples were incubated on agar under aerobic and anaerobic conditions. Bacteria were classified by MALDI-TOF mass spectrometry. We determined the frequencies of obligate and facultative oral bacteria and scored bacterial growth (0: none; 1: < 100 colonies; 2: >100 colonies; 3: dense). RESULTS: Bacteria were detected in 95% of skin-swab and 76% of mask samples. Median bacterial scores were 2 for forehead samples before and after treatment, and 1 for masks. Obligate and facultative oral bacteria were more frequent (6% and 30%) in samples from exposed forehead skin, which also showed increased bacterial scores (28%). 5% of samples contained methicillin-sensitive Staphylococcus aureus; 3% contained obligate anaerobes. CONCLUSION: Exposed forehead skin was significantly less contaminated with obligate oral bacteria than expected based on surgical mask findings. Exposed forehead skin showed increased contamination attributable to aerosol-producing procedures. The forehead's physiological skin microbiota may offer some protection against bacterial contamination.