William Blair & Company Initiates Coverage of Two Leading Dental Supply Companies.

CHICAGO -- William Blair & Company initiated research coverage of Sirona Dental Systems, Inc. (Nasdaq:SIRO) ($37.43; Outperform rating) and Patterson Companies, Inc. (Nasdaq:PDCO) ($37.28; Market Perform rating), two leaders in the dental market.

Analyst John Kreger estimated that Sirona, which has a dominant position in both digital imaging and CAD/CAM, would earn $0.75 per share in fiscal 2006 and $1.24 per share in fiscal 2007. In addition, he noted that he expects Sirona to issue fiscal 2007 guidance when the company releases its fourth-quarter results on December 8, 2007, and he will update his estimates following that call. He estimated Patterson, which boasts one of the broadest product offerings of consumables, equipment, technology, and support to the dental, veterinary, and rehabilitation markets, would earn $1.56 per share in fiscal 2007 and $1.77 in fiscal 2008.

"With the recently completed merger with Schick, Sirona now has a dominant position in both digital imaging and CAD/CAM, two of the areas with perhaps the greatest growth potential in the dental market over the next five to 10 years, in our view," Kreger said. "We believe Sirona (as a leader in high-end equipment) could offer investors one of the higher longer-term growth rates among the dental stocks."

Kreger added, "We believe the fundamental strength of the dental market, particularly the strong growth in equipment, should be a favorable driver of shares of Patterson, a recognized leader in dental equipment distribution, over the long term. Our outlook for Patterson is tempered somewhat in the near term, however, by ongoing challenges that are limiting revenue growth and pressuring margins (management changes, a slowdown in CEREC sales, increased cost structure)."

William Blair & Company, L.L.C. has received compensation for investment banking services from Patterson Companies, Inc. and Sirona Dental Systems, Inc. within the past 12 months, or expects to receive or intends to seek compensation for investment banking services in the next 3 months.

William Blair & Company, L.L.C. is a market maker in the securities of Patterson Companies, Inc. and Sirona Dental Systems, Inc. and may have a long or short position.

William Blair & Company, L.L.C. (www.williamblair.com) is a Chicago-based investment firm offering investment banking, asset management, equity research, institutional and private brokerage, and private capital to individual, institutional, and issuing clients. Since 1935, we have been committed to helping clients achieve their financial objectives. As an independent, employee-owned firm, our philosophy is to serve our clients' interests first and foremost.

For important disclosures and information regarding the firm's rating system, valuation methods and potential conflicts of interest, please visit: http://www.williamblair.com/Pages/news_story_dept.asp?uid=1126&depID=4

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