Hygiene, Volume 6, Issue 2 (June 2026) – 8 articles

Background: The effectiveness of non-surgical periodontal therapy largely depends on the ability of instruments to efficiently remove plaque and calculus from root surfaces. In recent years, innovative instruments such as LM Sharp Diamond™ curettes have been introduced, featuring a coated blade that maintains sharpness without the need for resharpening. The aim of this pilot in vitro study was to compare the cleaning efficacy of LM Sharp Diamond curettes with that of conventional stainless-steel curettes, hypothesizing that the diamond-coated instruments would demonstrate superior deposit removal efficiency. Materials and Methods: Extracted teeth were selected, fixed on a support, and the root surfaces were coated with black varnish to simulate plaque and calculus deposits. Standardized photographs were taken at baseline (T0). The coated root surfaces were then instrumented using LM Sharp Diamond™ curettes (test group) or traditional Gracey curettes (control group). After treatment (T1), the images were analyzed with Image Color Summarizer software 0.82 to calculate the percentage of cleaned surface. The results were subjected to statistical analysis performed by a professional statistician. Results: The results, obtained from the treatment of nine surfaces, demonstrated that LM Sharp Diamond™ curettes achieved greater and more consistent removal efficiency, with a mean reduction of 1.27 percentage points in residual coated area (RCA) deposits compared to traditional curettes (p = 4.45 × 10⁻⁶). Conclusions: Preliminary evidence suggests that LM Sharp Diamond™ curettes may ensure more effective residue removal than traditional steel curettes. Statistically, it has been shown that LM Sharp Diamond™ curettes provide a cleaner and more uniform surface than traditional steel curettes. Full article

Background/Objectives: Electronic cigarette (e-cigarette or vape) use is increasing, especially among young adults. Since there is no data on e-cigarette use among dental students in Costa Rica, this observational study aimed to evaluate the awareness and use of vapes in students at the Faculty of Dentistry, University of Costa Rica, and identify factors that influence their use. Methods: A cross-sectional online questionnaire was administered to a sample of dental students, and their responses were assessed. A total of 244 students, with a mean age of 21.38 ± 3.29 years, were recruited between October 2024 and May 2025. Multivariate binary logistic regression was employed to analyze factors influencing ever use of e-cigarettes. Results: Of the participants, 99.17% were aware of e-cigarettes, and 60.66% had used them at least once in their lifetime, with 8.61% being current users. Sixth-year students were more likely than first-year students to believe that e-cigarettes contain carcinogenic substances (p < 0.001). Participants that were unsure if vapes are more addictive than traditional tobacco cigarettes had lower odds of ever using them (OR = 0.092, 95% CI: 0.009–0.491, p = 0.004). Fourth-year dental students had higher odds of e-cigarette use compared to first-year students (AOR = 3.050, 95% CI: 1.102–8.804, p = 0.032). The survey showed that 23.84% of the participants learned about e-cigarettes from parents, friends, or classmates, and 19.94% learned about them from social media platforms like WhatsApp, Facebook, and Instagram. Conclusions: Most of the dental students demonstrated awareness of the health impacts of vaping. While more than half of the respondents had tried e-cigarettes, current use was low. Vaping behavior was influenced by academic level and perceptions of risk and addictiveness, with social networks and peers serving as primary information sources. These findings highlight the importance of integrating targeted educational interventions into dental curricula to strengthen awareness and promote evidence-based attitudes toward vaping. Full article

The present study proposes a narrative synthesis with an original translational approach to analyze the consequence of the global increase in waterborne microbial diseases. The focal point of this research is the relevance of these diseases for infection prevention and control (IPC) in dental settings and for public health. In order to analyze the main issues, the text focuses on studies published between January 2021 and September 2025. Over the past fifteen years, a small number of outbreaks and cases have been reported in dental settings. Nevertheless, the water utilized for dental care is frequently heavily contaminated with microbes, primarily opportunistic ones, which have the potential to cause pandemics of pseudo-infections. These include mainly Legionella, Pseudomonas, and nontuberculous Mycobacterium (NTM), antibiotic-resistant species, and other opportunistic pathogens with relative abundance exceeding 1%. This study focuses on five areas of research: (a) iatrogenic outbreaks and cases, and causes of underestimated waterborne infections; (b) the prevalence, complexity, and relevance of the dental unit water line contamination; (c) factors influencing water contamination in dental settings, (d) issues relating to products used for dental unit water line (DUWL) treatment, (e) main guidelines on water quality and European Union (EU) legislative acts and issues related to water testing. The text highlights the urgent need for greater awareness and preparedness in dental settings, as well as updated guidelines and rules to ensure the safety of patients and healthcare workers. Full article

Enterococci are found not only in warm-blooded animals but also as a resident population of water and an indicator of fecal pollution. The species Enterococcus haemoperoxidus and E. moraviensis are relatively new, having been detected in water. Strains with genes for biofilm formation can serve as reservoirs for gene transfer. The aim and novelty of this study were to determine whether the postbiotic substance (PS) of proteinaceous character (Durancin-like) produced by our strain Enterococcus durans ED26E/7 can inhibit in vitro the growth of biofilm-forming E. haemoperoxidus and E. moraviensis isolated from water sources. E. haemoperoxidus and E. moraviensis lacked the biofilm-forming genes ica, bap, ace, and fsrA. The bopD gene was found only in three strains of E. haemoperoxidus. The srtA gene was present in two strains of E. haemoperoxidus and E. moraviensis. Using the quantitative test, three strains showed low-grade biofilm-forming ability. They exhibited ɤ-hemolysis, and they were mostly susceptible to antibiotics. However, they were susceptible to PS Durancin-like ED26E/7. E. haemoperoxidus, the strains EHae466 and EMo494, showed the highest susceptibility to Durancin-like ED26E/7. Full article

Foodborne diseases represent a major public health concern, particularly those associated with dairy products contaminated with Staphylococcus aureus, a pathogen capable of producing heat-stable enterotoxins. This study evaluated the potential of native lactic acid bacteria (LAB) isolated from artisanal kefir grains as natural biocontrol agents in fermented dairy foods. Kefir grains obtained from three artisanal producers were microbiologically characterized, revealing LAB as the dominant group and the absence of Enterobacteriaceae. Strains belonging mainly to the genera Lactobacillus sensu lato, Leuconostoc, and Pediococcus were isolated and exhibited differentiated metabolic profiles. Safety assessment showed no hemolytic activity and an overall susceptibility to clinically relevant antibiotics, although genus-dependent intrinsic resistance patterns were observed. Several strains displayed enzymatic activities related to carbohydrate digestion and high tolerance to simulated gastrointestinal conditions, with survival rates exceeding 90% during both gastric and intestinal phases. Neutralized cell-free supernatant (CFS) demonstrated differential inhibitory activity, with significant antagonism of S. aureus and E. coli, comparable to those of commercial reference strains. In a yogurt model system stored at 4 °C, selected Lactobacillus and Pediococcus strains induced a progressive and significant reduction in S. aureus populations, achieving complete elimination to undetectable levels in shorter times than commercial probiotic strains. Overall, these results demonstrate that native LAB from artisanal kefir grains exhibit an adequate safety and functional profile, together with strong antagonistic activity, supporting their potential application as natural protective cultures to improve the food hygiene of fermented dairy products. Full article

Nurses are healthcare professionals who can play a leading role in preventing antimicrobial resistance, given their direct assistance to patients. For this reason, in-depth university training is desirable. This study was conducted to detect possible weak points in the university training about an important public health topic represented by general knowledge about antibiotics and antibiotic resistance. We carried out a survey on Knowledge, Attitudes, and Practices of students attending the Nursing Sciences course at the University of Messina, Italy, by administering an online standardised questionnaire that included general and specific questions about antibiotics and antibiotic resistance. General and specific scores were calculated. Some gaps were found about the knowledge of antibiotics (mean score: 3.6/4) and, especially, antibiotic resistance (mean score: 3.2/5). As expected, most of the incorrect answers to both antibiotic and antibiotic-resistance knowledge were given by students in the first year, but some gaps were also found among students in the last year. Given the growing role nurses can play in combating antibiotic resistance, these findings point to a possible information gap in the study course and highlight the need to enhance the current university training programmes with activities designed to increase knowledge on these important public health issues. Full article

Background: The emergence of alternative methods of obtaining groceries since the COVID-19 pandemic has raised new concerns regarding food safety. In this study, we sought to evaluate these concerns by evaluating how the procurement method of ground beef impacts the microbial load in the beef, as this has not been thoroughly studied. Methods: Specifically, we compared beef samples obtained from in-store shopping, grocery delivery, and meal kit delivery services to determine if these new, more convenient methods of grocery shopping impact the total microbial load or Escherichia coli present in the beef. We homogenized a total of 65 beef samples and plated dilutions on trypticase soy agar, MacConkey agar, and CHROMagar. Results: We found that in-store samples had the highest microbial load with an average of 5.06 log CFU/g, while grocery delivery samples resulted in an average of 4.76 log CFU/g and meal kit samples had an average of 4.23 log CFU/g when plated on TSA. This represents a 6.7-fold change between in-store samples and meal kit samples. These differences were not statistically significant (p = 0.1, ANOVA). When plated on MacConkey agar, in-store samples had a bacterial count at 3.0 log CFU/g, while grocery delivery samples had 2.99 log CFU/g and meal kit delivered samples had 3.05 log CFU/g. Suspected E. coli O157 colonies were detected using CHROMagar plates, as these plates function to change the coloration of positive E. coli O157 colonies to pink. Suspected E. coli O157 colonies were observed in three in-store samples, two grocery delivery samples, and one meal kit sample. After confirmatory agglutination testing, one meal kit sample was confirmed as E. coli O157. Conclusions: While trends suggest possible lower microbial contamination in delivery methods versus in-store shopping procurement, no statistical significance between methods was found. These findings indicate no significant changes in microbial loads in delivered ground beef, and the high variance suggests that all procurement methods still pose some level of risk. Full article

Conventional antimicrobial air filters often conflate physical interception with true biochemical inactivation, posing secondary aerosolization risks during maintenance. This study developed a lactoferricin B-functionalized polypropylene (LfCF) filter to provide a dual-action mechanism: electrostatic capture and robust contact-killing against bioaerosols. To rigorously decouple these mechanisms, a polyallylamine binder-only (PP+PAA) control was incorporated. Dynamic penetration assays at 10 cm/s revealed that the 2.0 mg LfCF achieved significantly lower viable penetration rates for Escherichia coli (41.2%) and λ phage (46.0%) compared to the PP+PAA control (75.1% and 76.3%). This substantial gap demonstrates instantaneous sublethal injury upon aerodynamic impaction, defined here as “dynamic inactivation.” Crucially, time-dependent elution assays confirmed a >2 log reduction in viable counts for both retained E. coli and λ phage on LfCFs within 60 min, definitively validating its genuine contact-killing capability. Furthermore, the amphipathic lactoferricin B peptide maintained exceptional biocidal efficacy even under high-humidity conditions (70% RH), overcoming the electrostatic shielding typical of traditional biopolymers, without increasing aerodynamic pressure drop. Finally, field validation in a dental clinic demonstrated an 83.3% reduction in airborne viable bioaerosols. As a passive, self-sterilizing engineering control, the LfCF offers a highly reliable intervention for mitigating occupational bioaerosol exposures. Full article