Scientific Studies

BruxZir® Scientific Studies

The comprehensive reports that follow evaluate the integrity and performance of BruxZir® Solid Zirconia. Biomaterials research, university studies and clinician reports were completed in order to examine how well a variety of materials embody the characteristics vital to high-quality dental restorations. Performance assessments, including long-term data, show that BruxZir restorations are excellent alternatives to PFMs and cast gold restorations. Furthermore, tests that evaluate strength, wear and translucency affirm the advantages of BruxZir Solid Zirconia compared to other all-ceramic restorations.

BruxZir Solid Zirconia Crowns and Bridges 5-year Clinical Performance Report

Conclusions: Over the five-year evaluation period, BruxZir Solid Zirconia Crowns and Bridges has proven to be an excellent restoration with respect to esthetics and dependability. It is highly recommended for posterior crowns and three- and four-unit bridges as well as implant-supported crowns and bridges. In select cases, in can be used confidently for anterior restorations. It received a 97% clinical rating.

Esthetics
92%
Resistance to fracture or chipping
96%
Resistance to marginal discoloration
99%
Wear Resistance
91%
Retention
90%

Translucent Zirconias: Tooth Reduction & Chairside Adjustment Issues

In the push to create translucent, colored, and partial zirconia formulations, the flexural strength and the transformation toughening unique to zirconia have been sacrificed. Clinicians are advised to: 1) avoid excessive chairside adjustments, 2) adhere to manufacturer’s recommendations for preparation design, and 3) for now, use the esthetic translucent zirconias only for anterior teeth. BruxZir Full-Strength, however, is the most durable of 118 white materials studied in clinical trials performed by Gordon J. Christensen Clinicians Report® in the past 40 years. A six-year clinical study of BruxZir Full-Strength used on molar crowns had a fracture rate of zero percent. The BruxZir cases received minimal tooth preparation (less than 1.0 mm occlusal reduction with a slight chamfer margin), RMGI cementation, and were placed on subjects with bruxing/clenching habits.

BruxZir Anterior Placement and One-Year Recall

At one year with over 300 restorations seated, Bruxzir Anterior has performed exceptionally well in the area of esthetics, lack of fracture or chipping, lack of marginal discoloration, and wear resistance. It is highly recommended for use in anterior restorations and selected posterior restoration. Its flexural strength surpasses most silica-based ceramic materials available to the dental profession. At one-year recall, BruxZir Anterior received a clinical performance rating of 100%.

0%
Rating at placement
0%
Rating at recall

BruxZir Anterior® Flexural Strength Tests

BruxZir Anterior® exhibited an average flexural strength exceeding 730 MPa in this recent study. The report joins a suite of evaluations that BruxZir Anterior has undergone in multiple test arenas, where data measurements can vary by method.

For this test, conducted at an accredited facility in Germany, the higher flexural strength values are related to a rare machine-polishing process for sample preparation. The time investment is extensive and a specialized machine is required, as only a few microns are removed in each pass. Although this polishing method diverges from standard milling and sintering processes, the test demonstrates the optimal strength that the BruxZir Anterior material can yield.

BruxZir Solid Zirconia: Superior Clinical Performance at 3+ Years

The clinical performance of BruxZir molar crowns was superior to all other tooth-colored materials studied previously by the TRAC research division of Clinicians Report® over the course of 39 years. Based on scanning electron microcoscope (SEM), clinical and laboratory examinations performed three-and-a-half years after placement, BruxZir crowns exhibited 23 percent less wear than the pressed ceramic-over-zirconia control group. Over the course of the study, BruxZir crowns received more wear than they caused, with no reports of microcracks, surface cratering or adverse occlusal system effects.

Translucency of CAD/CAM Ceramics

Specimens of the zirconia products were more translucent at 0.5 mm thickness than at 1.0 mm thickness. At the 0.5 mm thickness, the translucency parameter ranged from 10.3 to 10.7, and BruxZir was significantly more translucent than the other three products. At the 1.0 mm thickness, the translucency parameter ranged from 7.1 to 7.8, and BruxZir was significantly more translucent than Zenostar® Zr and Lava Plus. Translucency parameter was a function of wavelength when measured between 360–750 nm in reflection.

Zirconia VS. Porcelain Wear Study

Although conventional belief might suggest that zirconia’s high fracture strength and surface hardness would cause a greater degree of wear on enamel, a recent study found that the degree of wear on the opposing tooth was actually four times greater in dental porcelain than in polished, unglazed zirconia, suggesting that zirconia restorations are not only more fracture-resistant than porcelain restorations, but also gentler in their functional interaction with natural dentition.

BruxZir vs. Ceramco® 3 — A Comparative Wear Study

BruxZir Solid Zirconia and Ceramco 3 were recently tested in a comparative wear study. Each material was tested using the Willytech Chewing Simulator, which simulated the clinical performance of the material over a period of five years. After 1.2 million wear cycles under a load of 5 kg, BruxZir compared favorably to Ceramco 3 with barely detectable wear.

BruxZir vs. IPS e.max® Enamel Wear Test

Some dentists are concerned about the wear of enamel when opposing BruxZir full-contour zirconia crowns and bridges. In a recent study to measure the volumetric loss of enamel, glazed BruxZir was found to wear compatible with enamel and virtually identical to glazed IPS e.max.

Natural Enamel
0.29 ± 0.12 mm3
Glazed BruxZir
0.37 ± 0.23 mm3
Glazed IPS e.Max
0.41 ± 0.15 mm3

Transmission vs. Wavelength Graph

BruxZir materials exhibit higher light transmission resulting in a more natural shade value.

Scanning Electron Microscope Images

SEM of sintered colloidally processed BruxZir Solid Zirconia vs. sintered isostatically pressed zirconia.

High Flexural Strength

Lithium Disilicate ceramics have 400 MPa and typical zirconia materials have a flexural strength of more than 1200 MPa. However, because of post-powder processing, BruxZir Solid Zirconia dental restorations are able to exceed that strength threshold, with flexural strengths up to 1465 MPa.

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