Objective: Three-dimensional (3D) printing technology represents a novel method for manufacturing aligners. The aim of the present study was to assess the in-vitro cytotoxicity of 3D-printed aligners using different post-polymerisation conditions. Materials: Aligners were printed using the same 3D-print resin (TC-85DAC, Graphy, Seoul, Korea) and printer (AccuFab-L4D, Shining 3D Tech. Co., Hangzhou, China), followed by different post-curing procedures. Six aligners were post-polymerised for 14 min using the Tera Harz Cure and a nitrogen generator curing machine (THC2, Graphy, Seoul, Korea) (P1). A further six aligners were post-cured for 30 min on each side using the Form Cure machine (FormLabs Inc, Somerville, USA) (P2). The aligners were cut into smaller specimens (2 mm×2 mm) and sterilised at 121°C. The specimens were placed in 96-well plates containing Dulbecco’s Modified Eagle’s Medium (DMEM) at 37° for 7 or 14 days. The viability of MC3T3E-1 pre-osteoblasts cultured with DMEM was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The optical density of each cell culture was measured to assess cell viability, following which the data were statistically analysed using two-way and one-way ANOVA (α = 0.05). Results: The comparison of cytotoxicity revealed statistically significant differences between post-curing procedures and MTT timings ( P < 0.001). After 7 and 14 days, the cell viability of P2 was significantly reduced compared to P1 and the control groups ( P < 0.001), while P1 showed no significant differences compared to the controls. Overall, P2 post-curing exhibited moderate cytotoxicity, while P1 post-polymerisation was highly biocompatible. Conclusions: Different post-curing procedures may affect the in-vitro cytotoxicity of 3D-printed aligners. Clinicians should adhere to the manufacturer’s recommendations when using 3D-print resin.

Since the worldwide spread of SARS-CoV-2 infection, the management of COVID-19 has been a challenge for healthcare professionals. Although the respiratory system has primarily been affected with symptoms ranging from mild pneumonia to acute respiratory distress syndrome, other organs or systems have also been targets of the virus. The mouth represents an important route of entry for SARS-CoV-2. Cells in the oral epithelium, taste buds, and minor and major salivary glands express cellular entry factors for the virus, such as ACE2, TMPRSS2 and Furin. This leads to symptoms such as deterioration of taste, salivary dysfunction, mucosal ulcers, before systemic manifestation of the disease. In this review we report and discuss the prevalence and socio-demographics of taste disturbances in COVID-19 patients, analysing the current international data. Importantly, we also take stock of the various hypothesized pathogenetic mechanisms and their impact on the reported symptoms. The literature indicated that COVID-19 patients frequently present with gustatory dysfunction, whose prevalence varies by country, age and sex. Furthermore, this dysfunction also has a variable duration in relation to the severity of the disease. The pathogenetic action is intricately linked to viral action which can be expressed in several ways. However, in many cases these are only hypotheses that need further confirmation.

Background. Orthodontic appliances induce significant changes in the oral microbiome, but this shift in microbial composition has not been well established by the available evidence yet. Objectives. To perform a systematic review of existing literature in order to assess the taxonomic microbial changes in orthodontic patients during Fixed Appliance Treatment (FAT) and Clear Aligner Treatment (CAT), using next-generation sequencing (NGS) technique of the bacterial 16S rRNA gene. Search Methods and Selection Criteria. The search for articles was carried out in PubMed, including articles published in English until May 2021. They included every human study report potentially relevant to the review. Data Collection and Analysis. After duplicate study selection and data extraction procedures according to the PICOS scheme, the methodological quality of the included papers was assessed by the Swedish Council on Technology Assessment in Health Care Criteria for Grading Assessed Studies (SBU) method. Results. The initial search identified 393 articles, 74 of which were selected by title and After full-text reading, six articles were selected according to inclusion criteria. The evidence quality for all the studies was moderate. Conclusions. Orthodontic treatment seems to transiently affect the composition of subgingival microbiome, although not salivary, maintaining a stable microbial diversity. Different results were found in the shift of microbiome between plaque and saliva, depending on the type of orthodontic treatment. This review should be interpreted with some caution because of the number, quality, and heterogeneity of the included studies.

A large percentage of coronavirus disease 2019 (COVID-19) patients have taste dysfunction. Interleukin 6 (IL-6) levels in mild and moderate COVID-19 patients with the type (quantitative or qualitative) of taste disorders were compared in this observational study. The 208 COVID-19 patients (118 men and 90 women) revealing only taste dysfunctions as prodromic symptoms were classified as mild and moderate patients. Survey results were used to evaluate the taste disorder. The IL-6 levels were measured using a chemiluminescence assay. Statistical analysis was conducted using the Wilcoxon rank, Welch’s, and Mann–Whitney tests. The findings revealed that neither the presence of dysgeusia or phantogeusia nor the perception of sour and salty, differed statistically significantly between moderate and mild patients (P > 0.05). But between moderate and mild patients, there were statistically significant differences in how umami, bitter, sweet, and parageusia were perceived (P < 0.05). There was an impairment of multiple tastes up to ageusia in patients with high IL-6 levels. The findings demonstrated that parageusia and dysfunctions in umami, bitter, and sweet taste perception can be indicators of more severe forms of COVID-19.

The complexity of the use of antimicrobials for dental use (such as antibiotics) is directly related not only to the mode of onset of an oral infection (linked to numerous factors of local causality and comorbidity) but also to the predisposing risk for the general health of the patient with putative serious consequences related to the neck district. The abuse and misuse of antibiotics may lead to resistance to certain bacterial strains. In this regard, the evaluation of the risk/benefit of their use (especially in pregnant women) can be divided into two phases: risk analysis and subsequently risk management for the benefit of the patient for the oral pathology to be prevented or treated, respectively. This study seeks to focus on the issues and management of patients with certain antimicrobials during dental practice, placing special emphasis on new classes of antibiotics. Specific Aims: This study seeks to focus on the issues and management of patients with certain antimicrobials during dental practice, placing special emphasis on new classes of antibiotics.