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Veneering ceramic to the core is considered to be the weakest part of all-ceramic restorations. Zirconium dioxide, owing to its favorable properties such as high strength, chemical stability, and superior aesthetics, is the material of choice for fabrication of a core. The adhesion between the core and veneering porcelain is based on the same manner in which the connection occurs in metal-ceramic structures. However, the standard procedures for connecting zirconia to hard dental tissues and veneering materials do not achieve the required strength of bonding. The aim of this study was to investigate different surface treatments of the zirconium dioxide ceramic core for achieving highest adhesive bonding values to veneering porcelain. The study was primarily designed to investigate the bonding strength of the veneering porcelain to zirconia with in vitro macro shear bond strength test. The samples of zirconia were divided into four groups of 10 specimens, each according to the treatment of zirconium surface, and the results showed the highest bonding values for samples that were treated with the sandblasted group. AbstractKeywords ► shear bond strength ► zirconium dioxide ► CAD/CAM ► SEM Dent J Adv Stud 2018;6:14-19

A hybrid denture is fabricated over a metal framework that is retained by screws into the implants. The anterior part of a hybrid denture is fixed on implants and the posterior part of the denture is cantilevered. This case report presents the fabrication of a maxillary implant retained hybrid prosthesis. Four implants were placed in the maxillary arch. Framework was waxed, castable abutments were used, after-casting denture teeth were waxed to the hybrid framework, and a final try-in was done to verify and correct maxillomandibular relations before processing. The prosthesis was inserted after verifying fit of the framework. AbstractKeywords ► framework hybrid prosthesis ► implant ► screw retained prosthesis Dent J Adv Stud 2018;6:122-125

Abstract“The best of friends fall out with time and so do teeth.”Thus, there is a need to replace the lost teeth and the supporting structures for the patient's social demands and functional rehabilitation. Prosthetic treatment with complete dentures is a very common treatment modality; the biggest challenge in its fabrication is to duplicate the normal vertical dimension. Failure can be avoided by completing the treatment without changing the vertical dimension and obtaining an optimal facial proportion. There are many methods to record VD. Radiographic cephalometry has been used as a diagnostic tool in Prosthodontics for over five decades and numerous authors, like Ricketts (1981), McNamara (1984) and Slavicek (1984) developed and computerized these techniques to co-relate and record VD in patients. However cephalometric analysis can help to visualize skeletal and facial proportion relation. The present study was done to use the lateral radiographs with cephalometric analysis, as it could be a simple, non-technique sensitive, non-invasive and atraumatic way to determine VD for complete denture patients and also to compare physiologic methods (swallowing/phonetics) with cephalometric method to record lower facial height.

Introduction Provisional restoration is a critical component of fixed prosthodontics treatment, which must satisfy many inter-relative factors such as biological, mechanical, and esthetic. These restorations should have accurate marginal adaptation and optimum strength to maintain functional demands. The present “in vitro” study was conducted to evaluate the effect of water temperature and duration of immersion, on the marginal adaptation and microhardness of four different commercially available provisional restorative materials. Materials and Methods The 240 specimens were then seated on the stainless-steel die which simulated the prepared tooth, and evaluated for the marginal gap for four different provisional restorative materials and divided into four different groups A, B, C, and D. Each group was further divided into six subgroups according to temperature of water and time of immersion. In each group the samples were immersed in water at 20, 30, and 40 degrees, respectively for 5 and 10-minutes duration. Four different temporary restorative materials for crown fabrication were loaded each time to make temporary crowns. Results Each sample was placed under travelling stereoscopic microscope (20× magnification) and photographed. Results for each surface were obtained, and the average of three surfaces was calculated. Knoop hardness was measured using a microhardness tester. The study was subjected to statistical analysis, to know the statistical significance, of the effect of difference in time and temperature changes at the time of final polymerization on surface microhardness and marginal integrity of four different provisional restorative materials. Discussion The mean marginal discrepancies of bis-GMA (group B) at 20, 30, and 40°C for 5 and 10 minutes in water were smaller than the results of other groups. Microhardness evaluation showed that the poly ethyl methacrylate (PEMA) type resin exhibited significantly lower microhardness than the bis-acryl resin composites (Protemp 4 and Systemp.c&b) at both time and temperature intervals. Conclusion The bis-acryl composites material has the least marginal discrepancy in comparison with PEMA and polymethyl methacrylate (PMMA). The bis-acryl composites materials exhibit superior surface microhardness followed by PEMA and PMMA.