Moving within the second wave of the coronavirus (COVID-19) pandemic, dental education delivery has been profoundly affected by this crisis, so has the structure, evaluation, and future of dental education. Both pre-clinical and clinical dental education have experienced challenges ranging from fully online educational content to limited dental training for senior dental students. This crisis appears to be a tipping point that produced confusion in dental teaching especially clinical sciences. Although medical institutions immediately started to adapt to the unexpected COVID-19 crisis, dental and oral health educational services are profoundly impaired due to the dental team’s propinquity to the patient and the aerosols generated during routine dental therapeutic procedures. Dental students unlike other medical students are considered to be at the highest risk due to the nature of their clinical training that includes working in the oral cavity of patients using aerosol-generating equipment. Some dental schools have taken the leadership and documented their modifications during this pandemic; however, there is a serious need for further investigation and wide range screening of the situation in the dental schools during the COVID-19 crisis. The aim of this mini-review is to present these challenges and how academic dental institutions have implemented strategies to overcome them. Keywords: dental school

1 Main text

Coronavirus pandemic has affected all medical institutions, and dental schools are no exception [1]. Dentists including dental students have been considered as a very high-risk group by the Occupational Safety and Health Administration (OSHA) due to the potential for exposure to SARS-CoV-2 through aerosolgenerating clinical procedures [2]. The transmission mode of SARS-CoV-2 (the causative agent of COVID19) via respiratory droplets exposes dental healthcare providers to a high risk of infection. For this reason, many of the dental academic institutions have either closed temporarily or applied localized closures during the early wave of the pandemic. The reaction toward the COVID-19 crisis varied observing the available resources, institutional settings, and national (local) safety guidelines. Dental education has been affected given the application of various response strategies, including but not limited to transitioning from in-person classes into distant learning, changing the policies toward the in-patient care, canceling and modifying clinical rotations, professional meetings, and finally rescheduling of licensure examinations [3].

      Academic dental schools are known to be demanding and highly competitive learning environments. COVID-19 pandemic highlighted the differences between medical and dental institutions in the practical and clinical educational activities. Academic dental institutions are known as competitive and demanding learning communities, where students study preclinical and clinical dental courses designed to equip them with the essential knowledge and skills for licensure and clinical practice [4]. Clinical dental interventions require the integration of students’ technical and intellectual skills which require clinically oriented education in both basic medical and dental sciences, in addition to refined practice-based education in clinical dental care.

       As we are starting the third wave of COVID-19 pandemic, dental academic institutions in Egypt must learn from previous experiences and take the professional responsibility to share information. We hope that dental schools will be able to maintain adequate training in a safe clinical setting. Regarding clinical training, it is important to answer many questions that may help in understanding our future actions like are dental schools considered among high-risk workplaces or they should be treated like other educational in-campus settings? What will be the basic infection control standards? Are there any plans regarding the COVID-19 vaccination? Are there expected modifications on the future designs and infrastructure of educational dental settings including waiting areas, and spacing of dental units, and the central air ventilation? Although hybrid learning will probably be a keystone of future dental education, it is crucial to study extensively the possible pedagogical effects of the sudden change in dental educational strategies caused by the COVID-19 crisis. Finally, as an educator, I wish to go back soon to normal interactive dental education, but I believe that dental education might change significantly in the near future.

ABSTRACT

Background: There is little number of studies that address the inter-relationship of gestational diabetes mellitus (GDM) and periodontitis during pregnancy. Hence, this study was conducted to provide further evidence in the possible association between chronic periodontitis and GDM by evaluating the level of Tumor necrosis factor-alpha (TNF-α) of chronic periodontitis patients with GDM after phase I periodontal therapy.

Subjects and methods: This study was conducted on 40 subjects divided into 2 groups: 20 pregnant females suffering from gestational diabetes mellitus associated with moderate to severe chronic periodontitis and 20 systemically free pregnant females suffering from moderate to severe chronic periodontitis. The periodontal status of the subjects was assessed at baseline before phase I periodontal therapy and 2 months after completion of the treatment: All subjects have been screened by comprehensive periodontal examination and full periodontal charts were obtained. The following clinical parameters were assessed to determine the clinical periodontal status of patients: Plaque Index (PI), Gingival Index (GI), Probing Pocket Depth (PPD), and Clinical Attachment Level (CAL). Gingival crevicular fluid (GCF) and serum samples were collected from both study groups to detect TNF-α levels. Regarding the assessment of TNF-α, Real-time reverse-transcriptase Polymerase Chain Reaction (RT) PCR technique was used.

Results: Results of the present study observed statistically significant reduction in TNF-α levels after 2 months from phase I periodontal therapy. The current study showed that, there was a statistically significant positive (direct) correlation between TNF-α level, PI, GI, PPD and CAL measurement at baseline and after 2 months from phase I periodontal therapy.

Conclusion: It is shown that the levels of TNF-α in GCF and serum before treatment were higher in GDM group (group 1) than in the control group. Thus, the examination of TNF-α may enhance the understanding of pathogenesis of periodontitis and GDM and its assessment in the treatment process may result in better control of the disease.

This in vitro study was conducted to evaluate effect of surface treatment of zirconia and two resin cements on retentive force of zirconia crowns. Materials and Methods: Forty zirconia crowns (Amann Girrbach AG, Austria) were fabricated and divided into 2 groups according to type of resin cement, group (1) 1 Rely x ultimate clicker (3M Deutschland, Germany) and group (2) Rely x unicem (3M ESPE, USA), each group was then subdivided into 4 groups according to type of surface treatment, no surface treatment, sandblasting, sandblasting with silane and sand blasting with MDP. After cementation retention was measured by Materials Testing Machine (Instron Industrial Products, Norwood, USA) with a load cell of 5 kN. Data were recorded using computer software (Bluehill Lite; Instron Instruments). Results: Group (2) showed higher significant mean of retentive force than group (1). Self-adhesive resin cement showed higher mean of retention (82.72 ± 1 6.91) and (128.21 ± 19.88), compared to conventional (43.86 ± 5.89) and (92.95 ± 5.70), the difference was statistically significant. Sandblasting with MDP showed higher mean of retention (153.88 ± 12.07) and (166.19 ± 12.66), compared to group with no surface treatment (43.86 ± 5.89) and (82.72 ± 6.91) and the difference was statistically significant. Conclusions: Group (1) Rely x ultimate clicker resin cement (conventional resin cement) showed less mean of retentive force than group (2) Rely x unicem resin cement (self-adhesive).

Abstract

Objectives: This study was undertaken as an attempt to assess radiographic temporomandibular joint (TMJ) changes in relation to rheumatoid factor (RF), anticitrullinated protein (ACCP) antibodies and disease activity score 28 (DAS28) in rheumatoid arthritis (RA) patients to find the best predictor of rheumatoid affection of the TMJ with the ultimate goal of maintaining TMJ function and preventing joint damage.

Methods: 20 Rheumatoid Arthritis patients as well as 20 volunteers were included in this study. RA group were assessed for RF, ACCP, DAS28. Both groups were assessed by CBCT for TMJ dimensions and radiographic osteoarthritic changes. All data were statistically analyzed.

Results: Rheumatoid Arthritis group showed significantly less condylar height and more radiographic osteoarthritic changes than the control group. RF showed no significant correlation with either TMJ measurements or TMJ radiographic osteoarthritic changes. ACCP showed significant inverse correlation with condylar height and anteroposterior (AP) dimensions, but non-significant relation with mediolateral dimension and radiographic osteoarthritic changes. DAS28 showed significant inverse correlation with condylar AP and mediolateral dimensions. It also showed significant correlation with flattening of the TMJ condylar head and flattening of the articular fossa. Patients with high and moderate disease activity showed significantly smaller AP TMJ dimension than patients with low disease activity. Disease activity showed statistically significant direct correlation with all osteoarthritic changes except for erosions of the glenoid fossa and condyle.

Conclusion: Disease Activity Score28 score and disease activity are strong indicators of TMJ affection in RA patients when compared to RF and ACCP. ACCP is a better indicator of changes in condylar measurements than TMJ osteoarthritic changes. While RF is the least efficient indicator of TMJ involvement in RA patients.

the topical application of CoQ10 as an adjunct to non-surgical periodontal therapy improve the clinical and immunologic outcomes, but it not considered a strong modality for periodontal therapy. Tumor Necrosis Factor- α could be considered as strong laboratorymarker for periodontal disease activity. In addition, conventional periodontal therapy remains the cornerstone as basicand initial periodontal therapy.

ABSTRACT

Aim: This study aims to evaluate the effect of and compare between the piezosurgical ridge splitting and osseodensification in implant primary stability.

Subjects and Methods: 28 implants were divided into two groups. Group I: 14 implants in sites received piezosurgery technique. Group II: 14 implants in sites received osseodensification technique. Then, all implants were evaluated clinically for primary stability after implant insertion by Osstell mentor magnetic resonance device and radiographically for peri-implant bone density.

Results: unpaired t-test between the two groups showed moderate statistical significant difference in group II when compared with group I in both primary stability and bone density

Conclusion: The primary stability in both piezosurgical ridge splitting and osseodensification techniques is within normal range but in favor of osseodensification technique suggesting that osseodensification enhance the bone density thereby improve the implant primary stability.

Abstract

Aim: The aim of this study is to investigate the DNA ploidy and S-Phase Fraction (SPF) of some Salivary Gland Tumors (SGTs) in Egyptian patients and to investigate the correlation between these two biological parameters and the presumptive behavior of these neoplasms.

Methods: Flow cytometric analysis of DNA pliody and S-Phase Fraction (SPF) was done in 50 fresh tumor tissue sections of SGTs which diagnosed as 15 benign and 35 malignant tumors.

Results: 93.3% of the benign SGTs tumors were diploid, while only 34% of malignant tumors were diploid and 66% were aneuploid. The malignant SGTs had higher SPF than the benign tumors but with no significant difference. There was no significant correlation of ploidy status or SPF with the tumor grades of mucoepidermoid carcinomas.

Conclusion: DNA aneuploidy may be a key indicator for tumors activity and malignancy in SGTs, while the SPF has a minor role in the evaluation of SGTs activity.