Clinical Research Directory

PICN Versus Bioactive Composite for Cervical Restorations in Ballet Dancers

Background and Objectives: Professional ballet dancers endure high occlusal loads, increasing cervical defect prevalence. Conventional composites fail frequently under such conditions. This randomized clinical trial (RCT) compared 24 month performance of a polymer infiltrated ceramic network (PICN, VITA Enamic) versus a self curing bioactive composite (Stela) for cervical restorations. Materials and Methods: Twenty professional ballet dancers (40 cervical defects: 21 carious, 19 abfraction) were enrolled in a split mouth RCT. Each received one PICN inlay and one self curing composite restoration on two non adjacent defects. Restorations were assessed at 6, 12, and 24 months using United States Public Health Service (USPHS) criteria (primary: marginal integrity) and a dye penetration test. Secondary outcomes included secondary caries, hypersensitivity, and Oral Health Impact Profile-14 (OHIP 14). Statistical tests: McNemar, Fisher's exact, Kaplan-Meier, log rank (α=0.05). Results: At 24 months, no PICN restoration failed (0%). Self curing composite failures were 20% (carious) and 30% (abfraction) (exploratory uncorrected p=0.031; non significant after correction). Dye penetration was lower for PICN in abfraction defects (11% vs. 60%, adjusted p=0.048) but not in carious defects (9% vs. 30%, adjusted p=0.317). Kaplan-Meier survival favoured PICN (log rank p=0.001); 24 month survival probability: PICN 100% (95% CI: 83-100%), self curing composite 75% (95% CI: 55-95%). No secondary caries or serious adverse events occurred. Conclusions: PICN hybrid ceramic provided superior marginal integrity and zero failures over 24 months in cervical restorations of professional ballet dancers, outperforming the self curing composite. PICN inlays are recommended for abfraction defects. The self curing composite may be considered for carious defects when light curing is problematic, but patients should be informed of higher failure risk. Longer studies are needed.

Recycling of Three Pressable Ceramics With Different Weight Percentage

Introduction: Green dentistry, is high-technology approach that reduces the environmental impact of dental practices, improper disposal of dental materials wastes results in environmental hazards. Aim of the study: This studied will be performed o evaluate the effect of repressing of three different types of pressable ceramics, Ips Emax press, Lisi press and Celtra press with different weight percentages on patient satisfaction, mechanical properties, microstructural features and composition of these pressable ceramics. Materials \& Methods: Seventy five ( N=75) pressable ceramic discs will be constructed ,The samples will be divided to three groups (n=25 each) according to types and composition of pressed and repressed ceramics .Group 1: IPS Emax press .Group 2: Gc Lisipress Group 3: Celtrapress . Each group willbe divided into 5 sub-groups (n=5) according to the weight percentage of newly pressed and repressed ceramics. Subgroup A: 100% new ceramics. Subgroup B: 75% new and 25 % repressed ceramic .Subgroup C: 50% new and 50% repressed ceramics. Subgroup D:25%new and 75% repressed ceramics. Subgroup E: 100% repressed ceramics. Biaxial flexural strength will be measured using universal testing machine. X-ray diffraction will be performed to identify the crystalline phases, and a scanning electron microscope will be used to describe microstructural features. Energy dispersive X-ray analysis will be used to evaluate change in composition Also surface hardness will be evaluated. Patient satisfaction, plaque, cervical caries and marginal discoloration will be evaluated in a follow- up of one year (in vivo part).