Procera® Titanium
Implant Bridge

New
Precision of Fit–Procera® Implant Frameworks
Fit of Implant Framework Fabricated by Different Techniques
The Effect of Firing Cycles Wtih and Without the Addition of Porcelain on the Fit of a Long-Span Implant Framework
Silane to Enhance the Bond Between Polymethyl Methlmethacrylate and Titanium
Shear Bond Strength of Metal-Bonding Acrylic Resin to Ti
The Shear Strength of Polymethyl Methlmethacrylate Bonded to Titanium Partial Denture Framework Material

Abstract: The precision of fit between the implant components and the implant framework units has been reported in the literature using the conventional centroid measurement method. However, the accuracy of this method has been questioned because it evaluates only the centroids of the matched implant/framework bearing surfaces. It does not consider the influence of the angular orientations of the matched bearing surfaces. This presentation will describe a new method for measuring precision of fit called the MinGap best fit matching method that evaluates both the centroid gap size and the effect of the bearing surface angulations. The three-dimensional relationship of two matched bearing surfaces by the conventional centroid best-fit orientation method (cast vs. framework) involving six components were measured and centroid z-axis displacement data were collected. The same data sets were measured using the MinGap measurement method. The precision of fit between the cast and framework as measured by the two methods was compared. The angular orientations of the match bearing surfaces in many match data sets prevented the z-axis closure that occurs when using the conventional centroid measurement method. The overall average in the z-axis gap size as determined by the conventional centroid method was 80% of the gap size measured by the MinGap method.
Conclusions: The MinGap method for measuring the precision of fit between implants and their matched implant framework components provide a more accurate measurement of the z-axis gaps present.

Abstract: This study involved the evaluation of the precision of fit between an implant framework and a patient simulation model consisting of five implant abutments located in the mandibular symphysis area. One-piece cast frameworks were compared to Procera machined and laser welded frameworks using laser videography. Five frameworks of each type were measured using a laser digitizer and a graphics computer to determine a single point represented as the "Centroid" for each framework component and each implant abutment. Differences between the paired centroids for each framework/abutment interface are reported as x- and y-axis displacements, and z-axis gaps. The direction of the x- and y-axis displacements was determined.
Conclusions: There were significant differences (P=0.05) in the precision of fit between both the one-piece cast frameworks and the Procera framework when compared to the abutments in the patient simulation model. The laser welded framework exhibited a more precise fit than the one-piece casting with significant differences at three of the five prosthodontic interfaces when evaluated by the mean z-axis gap at the Centroid points.

Abstract: The fit of the implant framework to the implant within the jawbone has been suggested as contributing to the lifetime survival rate of the dental implant. It has also been suggested that the firing cycle used to fuse the veneering porcelain to the implant framework will affect the precision of fit of the framework to the implant abutment. The purpose of this study was to examine the influence of the firing cycle with and without the fusing of veneering porcelain on the precision of fit of the framework. Three duplicate laser-welded, titanium long-span implant frameworks formed the experimental population for this investigation. Three-dimensional data representing the six bearing surfaces within each framework were used to compute six single points called “centroid.” The displacements and angular gaps formed by the centroids and their respective bearing surface before firing were compared with data after multiple firing cycles and after the addition of the veneering porcelain. The comparison data were analyzed using a newly patented Polar coordinate system statistical analysis method. In the present paper only the centroid displacement will be reported. The three-dimensional distortion of the laser-welded titanium bearing surface occurred intermittently, and the magnitude was considerably different among the six locations in both linear and direction relationships.
Conclusions: The mean values (± Standard Deviation) of the three dimensional ray length of the means of six centroids, before firing and as the results of the third, fifth, tenth firing cycles and the porcelain addition were 0.013 mm (± 0.005), 0.097 mm (±0.030), 0.077 mm (±0.027), 0.082 mm (±0.035) and 0.046 mm (±0.011), respectively. The linear three-dimensional displacement of the centroid was deduced to almost half after the porcelain addition compared with during the multiple firing cycles.

Abstract: This study evaluated a new bonding material (Rocatec, ESPE) to determine its effect on the bond strength between titanium and polymethyl methylmethacrylate. Twenty rod shaped specimens of Grade-2 titanium (7.6 x 0.3 cm dia.) were divided into two groups consisting of 10 samples in each group. Group A received no pretreatment prior to the polymerization of the PMMA, while Group B was pretreated with 110 µm alumina air abrasive and the Rocatec material. Heat-cured denture base resin was processed around each titanium sample in a cylindrical shape approximately 0.9 x 1.5 cm. A Shell-Nielsen shear test was performed using the Universal Instron machine at a cross-head speed of 0.5 mm/minute to determine the bond strength in megapascals (MPa). Group B specimens (23.8 ± 1.78 MPa) had a shear strength 68% higher than Group A (16.1 ± 1.61 MPa) (P=0.001).
Conclusions: The results of this study indicated that surface pretreatment of Grade-2 titanium with 110 µm alumina air abrasive plus the Rocatec silane agent significantly enhanced the shear bond strength to PMMA.

Abstract: The purpose of this study was to determine if a specific metal-bonding denture base resin provided favorable bond strength to machined Ti. Fifteen rod-shaped specimens of commercially pure Grade-2 titanium were divided into two groups. Five specimens formed Group A or the control, while 10 specimens were placed in experimental Group B. Group A received no pretreatment prior to the polymerization of the denture base resin, while Group B was pretreated with 110 µm alumina air abrasive. Meta-Dent™ was processed around each titanium sample in a secondary cylindrical shape approximately 0.9 x 1.0 cm with the rods extending from each end. A Shell-Nielsen shear test was performed using the Universal Instron machine at a cross-head speed of 0.5 mm/minute to determine bond strength.
Conclusions: Group B shear strength (45.1 MPa) was 3.7 times greater than Group A (P? 0.01).

Abstract: This study determined whether three different surface management techniques for titanium improved the bond shear strength with polymethyl methacrylate. Thirty rod shaped specimens of titanium were divided into three equal groups: Group 1 received no pretreatment prior to the processing of the denture base material to its surface, Group 2 was pretreated with 110 µm alumina air abrasive, and Group 3 was pretreated with 110 µm alumina air abrasive plus silane (clear). Denture resin was processed around each specimen. A Shell-Nielsen shear test was then performed using the Universal Instron machine at a cross-head speed of 0.5 mm/minute to determine the bond shear strength in kilograms per square centimeter.
Conclusions: The bond shear strength of Group 3 was 63% greater than Group 1 (P<0.01; ANOVA-Scheffé interval 63 kg/cm2). The results of this study indicated that surface pretreatment of titanium with 110 µm alumina air abrasive plus silane coating significantly enhanced the bond shear strength of polymethyl methacrylate to titanium.