Ioana Codruta Mirica

Background: Peri-implant infections remain a major cause of dental implant failure, largely due to bacterial adhesion and biofilm formation on implant surfaces. This study aimed to investigate how surface topography influences bacterial colonisation and osteoblastic response. Methods: Titanium discs with machined (Ma), sandblasted, large-grit, and acid-etched (SLA), and nanostructured (Nano) surfaces were prepared, sterilised, and seeded with pre-differentiated dental follicle mesenchymal stem cells. Co-cultures with Enterococcus faecalis (E. faecalis) and Streptococcus oralis (S. oralis) were established under CO₂-free conditions, and cell–bacteria interactions were evaluated using fluorescence microscopy and quantitative image analysis. Results: Nano surfaces showed the highest osteoblastic adhesion and viability, while significantly reducing bacterial proliferation and biofilm formation compared with Ma and SLA surfaces. The sequence of colonisation influenced cell–bacteria dynamics, with early cell attachment limiting subsequent bacterial adhesion. Conclusions: Nano titanium surfaces may offer a dual benefit by promoting osseointegration while limiting bacterial adhesion. These findings support their potential use as surface modifications to reduce peri-implant infection risk and improve long-term implant success.

Background/Objectives: Polymeric barrier membranes (BMs) are usually used in guided bone regeneration to isolate the bone defect from the surrounding tissue, favoring bone apposition. This study proposes a third-generation BM made of polycaprolactone (PCL), loaded with different concentrations of nano-hidroxyapatite (nHAP) and gentamicin (GEN), and fabricated by electrospinning. Methods: The mechanical properties of the polymer, together with the fabrication procedure, offer porosity with interconnectivity to permit cell adhesion and proliferation. Bacterial contamination of the BM can induce infection at the bone level, leading to unfavorable clinical outcomes of the regeneration procedure. Results: Therefore, BMs have been proposed as carriers for local GEN antibiotic therapy, demonstrating antibacterial properties against S. aureus, S. mutans, and P. aeruginosa, depending on the drug concentration, while being negligibly affected by the nHAP content. X-ray diffraction, FTIR-ATR, and SEM allowed for BM structural characterization, demonstrating the presence of GEN/nHAP and establishing the fiber diameter, which influences the mechanical properties in dry and wet conditions and the drug release behaviorA BM cytotoxicity assessment, performed over 1 and 5 days, revealed that a high nHAP concentration provided protection against cytotoxicity, in contrast to GEN, and that cell proliferation and cell adhesion increased in the presence of nHAP. The BM’s bioactivity was demonstrated by mineralization after 21 days in simulated body fluid in an SEM/EDX analysis. Conclusions: The electrospun 15 wt.% nHAP and 2 wt.% GEN-loaded third-generation BM could be a promising alternative for guided bone regeneration.

The aim of this research is to develop new nanocomposite membranes (NMs) for guided bone regeneration from polycaprolactone (PCL), with different concentrations of gentamicin sulfate (GEN) and nano-hydroxyapatite (nHAP) through electrospinning. The obtained NMs were characterized for structure through SEM and AFM, which revealed the influence of GEN and nHAP on the fiber diameter. The addition of GEN lowered the fiber diameter, and the addition of nHAP increased the diameter of the fibers. The NMs demonstrated antibacterial properties against P. aeruginosa, S. aureus, B. cereus, and E. coli depending on the drug concentration, while being negligibly affected by the nHAP content. NM cytotoxicity assessment, performed once using the MTT assay, revealed no cytotoxicity. The developed NMs could be a promising alternative for guided bone regeneration.

(1) Background: The demands of patients for aesthetic and functional rehabilitation of edentulous areas led to the use of dental implants as therapeutic means on an increasingly large scale. This aspect determined the appearance of some infectious pathologies with a peri-implant starting point that can be complicated by various sinus diseases. The purpose of this review article is to synthesize the existing information in the specialized literature regarding the existing correlations between peri-implant and maxillary sinusitis. (2) Methods: The articles published in five databases were researched using different combinations of search terms. We selected 12 articles from the 250 found, by applying the inclusion and exclusion criteria and removing duplicates. (3) Results: We analyzed the included studies and we found that all of them reported a positive correlation between maxillary sinusitis and peri-implant infectious diseases. There are also reported other pathologies with a peri-implant infectious disease as a starting point such as abscesses, oro-antral communications, or foreign body reactions due to implant or bone graft materials migration. (4) Conclusions: This scoping review highlighted the existence of correlations between peri-implant and sinus pathology and the importance of preventing peri-implant diseases of an infectious nature to avoid the occurrence of these complications.

Medical implants have improved the quality of life of many patients. However, surgical intervention may eventually lead to implant microbial contamination. The aims of this research were to develop an easy, robust, quantitative assay to assess surface antimicrobial activities, especially the anti-nascent biofilm activity, and to identify control surfaces, allowing for international comparisons. Using new antimicrobial assays to assess the inhibition of nascent biofilm during persistent contact or after transient contact with bacteria, we show that the 5 cent Euro coin or other metal-based antibacterial coins can be used as positive controls, as more than 4 log reduction on bacterial survival was observed when using either S. aureus or P. aeruginosa as targets. The methods and controls described here could be useful to develop an easy, flexible and standardizable assay to assess relevant antimicrobial activities of new implant materials developed by industries and academics.

Periodontitis is an inflammatory disease that, if not treated, can cause a lot of harm to the oral cavity, to the patients’ quality of life, and to the entire community. There is no predictable standardized treatment for periodontitis, but there have been many attempts, using antibiotics, tissue regeneration techniques, dental scaling, or root planning. Due to the limits of the above-mentioned treatment, the future seems to be local drug delivery systems, which could gradually release antibiotics and tissue regeneration inducers at the same time. Local gradual release of antibiotics proved to be more efficient than systemic administration. In this review, we have made a literature search to identify the articles related to this topic and to find out which carriers have been tested for drug release as an adjuvant in the treatment of periodontitis. Considering the inclusion and exclusion criteria, 12 articles were chosen to be part of this review. The selected articles indicated that the drug-releasing carriers in periodontitis treatment were membranes and films fabricated from different types of materials and through various methods. Some of the drugs released by the films and membranes in the selected articles include doxycycline, tetracycline, metronidazole, levofloxacin, and minocycline, all used with good outcome regarding their bactericide effect; BMP-2, Zinc–hydroxyapatite nanoparticles with regenerative effect. The conclusion derived from the selected studies was that gradual drug release in the periodontal pockets is a promising strategy as an adjuvant for the treatment of periodontal disease.

(1) Background: Periimplantitis is an infectious condition that affects the periimplant tissue and is of bacterial etiology. However, to date, the exact bacterial flora involved in its occurrence is not known. The aim of this literature review was to summarize the articles published on this topic and to identify the main bacterial species isolated in periimplantitis. (2) Methods: The articles published in three databases were researched: Pubmed, Embase and Web of Science using Prisma guides and combinations of MeSH terms. We selected 25 items from the 980 found by applying the inclusion and exclusion criteria. (3) Results: We quantified the results of the 25 studies included in this review. In general, the most commonly identified bacterial species were Gram-negative anaerobic species, as Prevotella, Streptococcus, Fusobacterium and Treponema. (4) Conclusion: The most frequent bacteria in the periimplantitis sites identified in this review are Gram-negative anaerobic species, also involved in the pathogenesis of the periodontal disease.

Due to the impact of the Covid-19 pandemic on dental treatments, the present research aimed to assess the infection rate among dental practitioners from Romania and to analyze the economic impact of Covid-19 on dental offices. We designed a web-based survey distributed to dental practitioners from Romania. The survey included questions that assessed demographic data from the dentists who completed the questionnaire, along with economic aspects and epidemiological aspects related to the impact of the COVID-19 pandemic on dental practitioners. Five hundred and seven dentists completed the survey. Three-quarters of the assessed dental offices reported a decrease in the income and patient volume compared to 2019. More than half of the patients visiting the dental office paid more attention to the risk of infection and to prevention methods. Most dental offices implemented specific protective equipment for doctors. Three thousand seven hundred thirty-five dental practitioners were working in the 507 assessed dental offices, and among them, 238 COVID-19 cases of contamination were recorded. High contamination rates were registered in October (48, 20.1%), November (66, 27.7%), and December 2020 (52, 21.85%). Contamination mostly took place at home (114 cases, 47.8%) or resulted from event attendance. This study underlines an overall greater level of safety and an increased patient addressability in dental offices.

The aim of this research was to develop new electrospun membranes (EMs) based on polycaprolactone (PCL) with or without metronidazole (MET)/nano-hydroxyapatite (nHAP) content. New nHAP with a mean diameter of 34 nm in length was synthesized. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) were used for structural characterization of precursors and EMs. The highest mechanical properties (the force at maximum load, Young’s modulus and tensile strength) were found for the PCL membranes, and these properties decreased for the other samples in the following order: 95% PCL + 5% nHAP > 80% PCL + 20% MET > 75% PCL + 5% nHAP + 20% MET. The stiffness increased with the addition of 5 wt.% nHAP. The SEM images of EMs showed randomly oriented bead-free fibers that generated a porous structure with interconnected macropores. The fiber diameter showed values between 2 and 16 µm. The fiber diameter increased with the addition of nHAP filler and decreased when MET was added. New EMs with nHAP and MET could be promising materials for guided bone regeneration or tissue engineering.