Aim:To evaluate the effect of the implant's thread cross sectional design on the micromotion of the implants in different bone qualities. Materials and methods:In this finite element analysis study, four implant models exhibiting four different thread designs were created using Solidworks software.Each model was assembled in four different bone quality models resulting in 16 groups.Each group was examined for micromotion under 100N force using ANSYS software.Results: D1 bone showed the lowest micromotion while D4 bone showed the highest, regardless the thread design.In D1 and D2 bone, v-shaped thread showed the lowest micromotion, which was lower than the square thread and the buttress was lower than the reverse buttress.While in D3 and D4 bone, the lowest micromotion was observed with the square thread, which was lower than the v-shaped and the reverse buttress thread was lower than the buttress thread.Conclusion: Micromotion decreases as the bone quality increases irrelevant of the implant thread design.In D1 and D2 bone, the best thread to be used is the v-shaped thread, while in D3 and D4 bone, the best is the square shaped thread.

Aim:This study aimed to compare the adhesion of Candida Albicans to the fitting surface of Bre-Flex Versus PEEK removable partial denture bases and mucosa beneath them, , in patients with maxillary class III modified 1 Kennedy's classification Subjects and methods: Eighteen patients having Kennedy class III modification I Maxillary partially edentulous ridges with fully dentate mandibular arch were divided into two equal groups to fabricate the thermoplastic materials. The first group received Bre.Flex material. The second group received PEEK material. For each studied group, microbiological evaluation was carried-out according to the follow-up recall visits: at the denture insertion, three weeks and four weeks after denture insertion. The collected data were tabulated and statistically analysed. Results: showed that the difference between the two groups was statistically significant was reported between two groups regarding microbiological evaluation. Conclusion: Candida Albicans can grow on both denture base material (Bre-Flex and PEEK). Swabs collected from oral mucosa in Bre-Flex group shows higher number of Candida colonies in comparison to the number of colonies in PEEK group

Statement of the problem: Flexible denture is usually chosen by patients whom esthetics is their top priority, who refuse preparation of the abutment teeth or who have allergy to the metal. Patients are looking for restoring their lost teeth. However, the purpose of denture construction should involve the maintenance of the surrounding tissue health. Aim of study: to correlate the type of denture base with the distribution of masticatory forces through examining the histological changes in the alveolar mucosa. Methods: 12 partially edentulous patients with the same missing teeth were selected from Prosthodontics outpatient clinic, Faculty of Dentistry, Cairo University. 6 Patients received metallic partial denture while the rest received flexible partial denture. 2 smear biopsies were taken on the day of delivery and 6 month after denture insertion, stained with PAP and examined histologically to assess the number of keratinized cells. Results: by Using paired-t-test it show that both types of denture bases altered alveolar mucosal keratinization but there was a significant difference in number of keratinized cells among pretreatment, after-metallic, and after-flexible denture insertion. Flexible partial denture showed thinner and less keratinized epithelium. Conclusion: Any prosthetic restoration placed in the oral cavity will induce some mucosal changes .The biocompatibility of the prosthesis with oral tissue should be considered in addition to patient’s and dentist’s preference

Statement of problem: marginal inaccuracy causes a space between restoration and prepared tooth, which accelerates cement dissolution, leading to secondary caries, pulpal lesions, postoperative sensitivity, periodontal disease and marginal discoloration. Marginal gap should be less than 120µm. Aim: to evaluate vertical marginal gap of PEEK (Bio-HPP) veneered with CAD/CAM composite veneer (HIPC) as compared to zirconia veneered with CAD-On lithium disilicate glass ceramic. And the effect of ageing on the gap of both restorations. Material and methods: 40 extracted molars were prepared, divided into two groups, control group (ZR) (n=20), teeth restored with IPS e.max ZirCAD copings veneered with IPS e.max CAD and intervention group (PEEK) (n=20), teeth restored with breCAM BioHPP copings veneered with BreCAM.HIPC. Each specimen was photographed using Leica S8 APO stereomicroscope under magnification 32X and image analysis was done. Measurements were taken twice before and after thermo-mechanical cycling. Results: PEEK group recorded higher gap mean values (49.88±7.97um) than zirconia (18.39±3.1um). This was significantly (p < 0.05) as confirmed by Mann-Whitney test, but all measurements were clinically acceptable. And Thermo-mechanical cycling had no effect of on both groups. Conclusion: PEEK veneered with composite can be used intra orally for single crown restorations.

Background: Most of the available therapeutics of oral lichen planus are associated with adverse effects and there is no sufficient evidence to support the effectiveness of these modalities over placebo or over each other. Micronutrients including antioxidants modify the immune system function and are considered promising alternatives in management of OLP with negligible side effects. The current trial assessed the effect of adjunctive use of systemic vitamin E in symptomatic oral lichen planus patients. Methods: This randomized controlled clinical trial includes 30 symptomatic (erosive and atrophic) oral lichen planus patients in two parallel groups (intervention – topical triamcinolone acetonide adhesive paste and Vitamin E, control - topical triamcinolone acetonide adhesive paste and placebo), with allocation ratio 1:1. Outcome measures were pain intensity, clinical improvement and salivary level of total antioxidant capacity. Results: Mean amount of pain reduction and clinical improvement were greater in the experimental group with statistically significant difference. Mean amount of total antioxidant capacity upregulation was greater in the control group with no statistical difference. Conclusion: Adjunctive use of systemic vitamin E has shown promising results in management of OLP with no side effects.

Background: The relation between diabetes mellitus and periodontitis has been discussed for years. Many adipokines were reported to play a major role in periodontal inflammation. Chemerin is one of these adipokines which is blamed to be involved in inflammatory conditions such as diabetes. Fibroblast growth factor 21 (FGF21) is another adipokine which is believed to induce regulation of glucose. The current study aimed to spot the light on the potential role of gingival crevicular fluid (GCF) level of FGF21 and chemerin as biomarkers of periodontal disease activity and an attempt to understand their role in the link between periodontitis and diabetes. Methods: The study was conducted on 45 individuals, 15 diabetic patients with periodontitis, 15 periodontitis patients and 15 healthy controls. GCF samples were collected from all participants for assessment of chemerin and FGF 21. Samples were analysed using enzyme linked immunosorbent assay (ELISA). Results: Periodontitis patients with diabetes had significant higher levels of chemerin and FGF21 than the periodontitis patients without diabetes followed by healthy controls. ROC analysis showed a 100% diagnostic accuracy for chemerin and FGF21. Conclusion: FGF21 and chemerin in GCF are valuable biomarkers of periodontal disease suggesting a role in the link between diabetes and periodontitis.