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This paper’s primary aim is to outline relevant aspects regarding the biocompatibility of PMMA (poly(methyl methacrylate))-based materials used for obtaining interim prosthetic restorations, such as the interaction with oral epithelial cells, fibroblasts or dental pulp cells, the salivary oxidative stress response, and monomer release. Additionally, the oral environment’s biochemical response to modern interim dental materials containing PMMA (obtained via subtractive or additive methods) is highlighted in this review. The studies included in this paper confirmed that PMMA-based materials interact in a complex way with the oral environment, and therefore, different concerns about the possible adverse oral effects caused by these materials were analyzed. Adjacent to these aspects, the present work describes several advantages of PMMA-based dental materials. Moreover, the paper underlines that recent scientific studies ascertain that the modern techniques used for obtaining interim prosthetic materials, milled PMMA, and 3D (three-dimensional) printed resins, have distinctive advantages compared to the conventional ones. However, considering the limited number of studies focusing on the chemical composition and biocompatibility of these modern interim prosthetic materials, especially for the 3D printed ones, more aspects regarding their interaction with the oral environment need to be further investigated.

Periodontitis represents a complex inflammatory disease that compromises the integrity of the tooth-supporting tissue through the interaction of specific periodontal pathogens and the host’s immune system. Experimental data help to outline the idea that the molecular way towards periodontitis initiation and progression presents four key steps: bacterial infection, inflammation, oxidative stress, and autophagy. The aim of this review is to outline the autophagy involvement in the pathogenesis and evolution of periodontitis from at least three points of view: periodontal pathogen invasion control, innate immune signaling pathways regulation and apoptosis inhibition in periodontal cells. The exact roles played by reactive oxygen species (ROS) inside the molecular mechanisms for autophagy initiation in periodontitis still require further investigation. However, clarifying the role and the mechanism of redox regulation of autophagy in the periodontitis context may be particularly beneficial for the elaboration of new therapeutic strategies.

A provisionalization sequence is essential for obtaining a predictable final prosthetic outcome. An assessment of the mechanical behavior of interim prosthetic materials could orient clinicians towards selecting an appropriate material for each clinical case. The aim of this study was to comparatively evaluate the mechanical behavior—with compressive and three-point flexural tests—of certain 3D-printed and conventional resins used to obtain interim fixed dental prostheses. Four interim resin materials were investigated: two 3D-printed resins and two conventional resins (an auto-polymerized resin and a pressure/heat-cured acrylic resin). Cylindrically shaped samples (25 × 25 mm/diameter × height) were obtained for the compression tests and bar-shaped samples (80 × 20 × 5 mm/length × width × thickness) were produced for the flexural tests, observing the producers’ recommendations. The resulting 40 resin samples were subjected to mechanical tests using a universal testing machine. Additionally, a fractographic analysis of failed samples in bending was performed. The results showed that the additive manufactured samples exhibited higher elastic moduli (2.4 ± 0.02 GPa and 2.6 ± 0.18 GPa) than the conventional samples (1.3 ± 0.19 GPa and 1.3 ± 0.38 GPa), as well as a higher average bending strength (141 ± 17 MPa and 143 ± 15 MPa) when compared to the conventional samples (88 ± 10 MPa and 76 ± 7 MPa); the results also suggested that the materials were more homogenous when produced via additive manufacturing.

All social and economic systems worldwide, including the educational one have been disrupted by escalating the global COVID-19 pandemic. One of the most impacted areas were the medical and dental education fields, due to the forced break from clinical practice during the lockdown, which affected both the educational part, as well as the patients. Thus, the main goal of our research was to investigate the impact of the COVID-19 pandemic on the dental students’ education as related to their perceptions and evaluations, in Carol Davila University of Medicine and Pharmacy, Bucharest, Romania. A cross-sectional study was conducted on 878 dental students who reported their perception of the psychological and educational impact of this period by completing a Google Forms questionnaire. Collected data were statistically analyzed using Stata/IC 16. There was a severe psychological impact among the respondents, the levels of stress being perceived as high and very high (33.83%, n = 297; 28.59%, n = 251), similar to high and very high anxiety feelings (26.54%, n = 233; 24.26%, n = 213). Very high educational impact from the point of view of the acquisition of practical skills (48.52%, n = 426) and future professional perspectives (38.95%, n = 342) were recorded. While online theoretical learning ability was principally low (37.93%, n = 333) despite consistently modified time allocated to the individual study (44.35%, n = 389), most of the students evaluated the efficiency of lecturers in online courses as neutral (41.12%, n = 361). New dentistry teaching programs will have to be adopted taking into account the dynamics of the pandemic and its strong impact on our students, in order to improve both their wellbeing and the sustainability of dental education.

The purpose of this study is to outline relevant elements regarding the biochemical interactions between prosthetic materials used for obtaining implant-supported restorations and the oral environment. Implant-supported prostheses have seen unprecedented development in recent years, benefiting from the emergence of both new prosthetic materials (with increased biocompatibility and very good mechanical behavior), and computerized manufacturing technologies, which offer predictability, accuracy, and reproducibility. On the other hand, the quality of conventional materials for obtaining implant-supported prostheses is acknowledged, as they have already proven their clinical performance. The properties of PMMA (poly (methyl methacrylate))—which is a representative interim material frequently used in prosthodontics—and of PEEK (polyether ether ketone)—a biomaterial which is placed on the border between interim and final prosthetic use—are highlighted in order to illustrate the complex way these materials interact with the oral environment. In regard to definitive prosthetic materials used for obtaining implant-supported prostheses, emphasis is placed on zirconia-based ceramics. Zirconia exhibits several distinctive advantages (excellent aesthetics, good mechanical behavior, biocompatibility), through which its clinical applicability has become increasingly wide. Zirconia’s interaction with the oral environment (fibroblasts, osteoblasts, dental pulp cells, macrophages) is presented in a relevant synthesis, thus revealing its good biocompatibility.

Xanthine oxidoreductase (XOR) activity plays an important role as a pivotal source of reactive oxygen species. The aim of our study was to investigate possible correlations of XOR serum levels with oxidative stress (total antioxidant capacity - TAC, anti-oxidative stress responsive 1 antibody - OXSR1) and inflammation markers (interleukin 6 - IL-6), in 20 hemodialysis diabetic patients. The present study included the hemodialysis diabetic patients group (10 males and 10 females) and the control group (20 healthy volunteers). For serum XOR (ng/mL), TAC (U/mL) and OXSR1 (ng/ml) measurements we have used the ELISA technique. Serum IL6 (pg/mL) was performed using an automatic immunoassay system (Immulite 1000, Siemens- Germany). Comparing the two groups, our results revealed significantly increased serum levels for XOR (6.2�1.5 / 3.9�1.1); OXSR1 (11.3�2.9 / 6.2�2.1) and IL6 (7.0�1.2 / 5.0�0.4). Patients� serum levels of TAC were significantly decreased compared with the control group values (25.2�3.9 / 33.5�2.8). It becomes more and more obvious that oxidative stress is an important element initiating diabetic microvascular complications, including diabetic kidney disease. Our results suggested that XOR should be regarded as an important target in the attempt to reduce oxidative stress in the context of diabetic kidney disease.

This review aims to evaluate the effectiveness of professional topical fluoride application on the prevention of dental caries in primary and permanent dentition. A web search was conducted for English papers published from 2000 to 2020, using various digital resources (Pubmed, Google Scholar, Cochrane Library, and ResearchGate). The keywords were “professionally applied fluoride”, “fluoride gel”, “fluoride varnish”, “fluoride foam”, “fluoride mouthrinses”, and “non-cavitated caries lesions”. Inclusion criteria: (a) participants: children and adolescents, treated in a dental care setting; (b) intervention: professionally applied fluorides (gel, varnish, foam, mouthrinse); (c) comparator: no professional treatment or other preventive treatments; (d) outcomes: clinical effectiveness (e.g., caries reduction, tooth remineralization); (e) study design: randomized controlled trials, systematic reviews, meta-analyses; (f) publication period: 1 January 2000–31 December 2021. Clinical studies about home-use fluoride products, discussion papers, in-vitro studies, case reports, non-English articles, and studies with unclear methodology were excluded. Topical fluoride applications are indicated for patients with active smooth surface caries and for patients in high caries risk groups. Both APF gel and fluoride varnish are effective and can be recommended for caries prevention in primary and permanent teeth. For children under the age of 6, only 2.26% fluoride varnish is recommended.