Medical Device Daily Associate

Astra Tech (Waltham, Massachusetts), a unit of the AstraZeneca (London) group, reported FDA approval and U.S. availability of its OsseoSpeed product, a fluoride modification to its popular TiOblast surface that the company said promotes faster bone growth and improves on the clinically documented TiOblast surface for improved treatment outcomes in dental implant surgery.

OsseoSpeed was designed to provide more rapid bone growth during the crucial healing period immediately following implant placement. And Astra Tech said that studies have shown that the new implant improves bone growth speed, surface contact area and bonding strength by 30% to 50% over un-modified roughened titanium implants.

The company said the new material is designed to offer dental professionals faster osseointegration – meaning anchorage of the implant in new bone – even in patients with sub-optimal or marginal bone quality.

"OsseoSpeed and the other key features of the Astra Tech Dental Implant System provide optimal long-term results in which surgeons and patients alike can have confidence," said Anders Holm n, dental medical director at Astra Tech AB (M lndal, Sweden), where the subsidiary has its international headquarters. "We are proud to make this technology available in the United States."

Holm n told Medical Device Daily that the OsseoSpeed is a further enhancement to the company's breakthrough TiOblast rough surface and represents roughly 12 years of research to improve upon an already well received implant improvement. The new fluoride-modified surface improves on the TiOblast surface to further stimulate bone healing and allow for more effective and reliable early loading, he added.

The micro-roughened TiOblast surface is created by blasting the implant with titanium dioxide particles to create a surface topography that transfers physiological loads and enhances bone stimulation, resulting in increased bone-to-implant contact area and better implant/bone interlock.

Aside from more rapid bone development, Holm n said, "The great benefit now with this OsseoSpeed surface [is] . . . increased confidence and security of the quality of predictability of the treatment that can take [dental implants] to another level."

"Our research has shown that the fluoride-modified surface leads to faster osteoblast differentiation that may be advantageous in sub-optimal clinical situations," said Lyndon Cooper, DDS, PhD, Department of Prosthodontics, University of North Carolina at Chapel Hill, School of Dentistry. "More bone growth more rapidly may enable dental professionals to perform implant surgery with greater confidence."

Once the implant is firmly attached to the bone, the dental professional selects and places an abutment onto which prosthetic teeth can be attached. The result of the procedure is replacement teeth that very closely match the patient's original teeth in terms of look, feel and function, according to Astra Tech.

Other features included in the company's implants that further enhance healing are its Conical Seal Design and MicroThread retention elements. The tight and precise-fitting implant-abutment relation of the Conical Seal Design is designed to make abutment connection a quick and simple procedure. To maintain bone, dental implants must be designed to mechanically stimulate the surrounding bone. The neck of the implant, which is the most critical part of the implant-bone interface, stimulates surrounding bone with MicroThread retention elements – tiny threads that offer optimal load distribution and lower stress values.

"The Astra Tech Dental Implant System is backed by a 10-year record of clinical and preclinical research," said Clark Stanford, DDS, PhD, University of Iowa, College of Dentistry (Iowa City, Iowa) in a statement. "And ongoing studies of the OsseoSpeed surface have demonstrated enhanced qualities compared to other rough implant surfaces in terms of the speed of bone growth, surface contact area, and bonding strength – the primary factors in a successful implant placement."

In two studies, Holm n reported, TiOblast implants, and TiOblast implants with fluoride modification, were exposed to solutions containing calcium and phosphate. The implants with fluoride-modified surfaces absorbed significantly more calcium phosphate, indicating a significantly greater capacity to promote bone formation and bone bonding, he said.

Holm n also noted that fluoride-modified fixtures have been implanted into bone in a number of studies. Histological analysis of the bone-to-implant interface has illustrated superior bone response and attachment to the OsseoSpeed implant surface with higher bone-to-implant contact documented as early as one month after implant placement.

In a study with two months' observation before histological analysis, new bone formation was identified on OsseoSpeed surfaces that had been placed in the bone marrow of rabbit tibia. This study also tested implant stability, as measured by removal torque, with OsseoSpeed demonstrating significantly higher retention in bone compared to machined or rough surface implants.

The OsseoSpeed surface is available in four diameters (3.5 mm, 4 mm, 4.5 mm and 5 mm), all of which include internal "double-hex" to provide anti-rotation and allow for convenient indexing of the abutment.

According to the company, the U.S. market for dental implants is approaching $400 million and it estimates it to grow by as much as 20% each year for the next five years to nearly $1 billion in 2011. Astra Tech reports more than 500,000 dental implants placed in the U.S. last year.

In addition to dental implants, Astra Tech makes catheters, blood recycling systems, respiratory devices and diagnostic imaging products.