Computer-based implant planning involving a prefabricated custom tray with alumina landmark structures.

The purpose of this technical report was to describe a method for the fabrication of a custom tray with landmark structures to coordinate cone beam computed tomography and scan data for use in guided implant surgery in patients with numerous artifact-causing metal prostheses. The fabricated custom tray can be used to coordinate cone beam computed tomography data and scan data from the dentition, as well as to fabricate the prostheses.

Effect of air-particle pressures on the surface topography and bond strengths of resin cement to the hybrid ceramics.

This study aimed to determine the appropriate pressure for airborne-abrasion by comparing the shear bond strength values for different hybrid ceramic surfaces. Two materials were used to produce hybrid ceramic specimens: Lava Ultimate and MAZIC Duro. The group of specimens whose surfaces were not subjected to airborne-abrasion was set as the control group. In the experimental group, airborne-abrasion was performed at pressures of 0.1, 0.2, and 0.3 MPa. After the adhesive and resin cement was applied, an SBS test was performed. For the MAZIC Duro block, the SBS increased monotonically with the airborne-abrasion pressure increased, peaking at 0.3 MPa. For the Lava Ultimate block, the SBS increased as the airborne-abrasion pressure increased to 0.2 MPa, and then decreased in the 0.3-MPa group, thereby peaking at 0.2 MPa. This study has confirmed that the bonding strength varies with the material used even when applying the same surface treatment.

Effect of Surface Treatment on Shear Bond Strength between Resin Cement and Ce-TZP/Al2O3.

Purpose. Although several studies evaluating the mechanical properties of Ce-TZP/Al2O3 have been published, to date, no study has been published investigating the bonding protocol between Ce-TZP/Al2O3 and resin cement. The aim of this study was to evaluate the shear bond strength to air-abraded Ce-TZP/Al2O3 when primers and two different cement types were used. Materials and Methods. Two types of zirconia (Y-TZP and Ce-TZP/Al2O3) specimens were further divided into four subgroups according to primer application and the cement used. Shear bond strength was measured after water storage for 3 days or 5,000 times thermocycling for artificial aging. Results. The Y-TZP block showed significantly higher shear bond strength than the Ce-TZP/Al2O3 block generally. Primer application promoted high bond strength and less effect on bond strength reduction after thermocycling, regardless of the type of cement, zirconia block, or aging time. Conclusions. Depending on the type of the primer or resin cement used after air-abrasion, different wettability of the zirconia surface can be observed. Application of primer affected the values of shear bond strength after the thermocycling procedure. In the case of using the same bonding protocol, Y-TZP could obtain significantly higher bond strength compared with Ce-TZP/Al2O3.

The influence of ceramic surface treatments on the tensile bond strength of composite resin to all-ceramic coping materials.

STATEMENT OF PROBLEM: An increasing demand for esthetic restorations has resulted in the development of new ceramic systems, but the fracture of veneering ceramics still remains the primary cause of failure. Porcelain repair frequently involves replacement with composite resin, but the bond strength between composite resin and all-ceramic coping materials has not been studied extensively. PURPOSE: The purpose of this study was to evaluate the tensile bond strength of composite resin to 3 different all-ceramic coping materials with various surface treatments. MATERIAL AND METHODS: Thirty specimens (10 x 10 x 2 mm) each of lithium-disilicate ceramic (IPS Empress2 [E]), alumina ceramic (In-Ceram Alumina [I]), and zirconia ceramic (Zi-Ceram [Z]) were fabricated. Feldspathic ceramic (Duceram Plus [F]) was used as the control. Each material was divided into 3 groups (n=10), and 3 different surface treatments were performed: airborne-particle abrasion with 50-microm alumina particles (Ab); airborne-particle abrasion with 50-microm alumina particles and acid etching with 4% hydrofluoric acid (Ae); or airborne-particle abrasion with 30-microm alumina particles modified with silica acid (Si). After surface treatment of ceramic specimens, composite resin cylinders (5-mm diameter x 10-mm height) were light polymerized onto the ceramic specimens. Each specimen was subjected to a tensile load at a crosshead speed of 2 mm/min until fracture. The fracture sites were examined with scanning electron microscopy to determine the location of failure during debonding and to examine the surface treatment effects. Two-way analysis of variance and the Duncan multiple comparison test (alpha=.05) were used to analyze the bond strength values. RESULTS: There were significant differences in the bond strengths for both ceramics (P<.001) and surface treatments (P<.001) and the interaction (P<.001). The Duncan analysis yielded the following statistical subsets of the bond strength values: (FAe, ISi, EAe, ZSi) > FAb > (FSi, EAb, ESi) (IAb, IAe) > (ZAe, ZAb). The results illustrate no differences within the parentheses but statistically significant differences among the groups. CONCLUSION: Alumina and zirconia ceramic specimens treated with a silica coating technique, and lithium disilicate ceramic specimens treated with airborne-particle abrasion and acid etching yielded the highest tensile bond strength values to a composite resin for the materials tested.