American Dental Partners to Present at the William Blair & Company Small-Cap Growth Stock Conference

Market Wire, September, 2008

American Dental Partners, Inc. (NASDAQ: ADPI) announced today that Breht T. Feigh, Executive Vice President, Chief Financial Officer and Treasurer, will present at the William Blair & Company Small-Cap Growth Stock Conference in New York City on Tuesday, October 7, 2008, at 11:20 a.m. EDT.

The presentation will be webcast live and will be available in the Investor Relations section of the Company's website at www.amdpi.com . An archived version of the presentation will also be available through the Company's website for seven days following the conference.

American Dental Partners is one of the nation's leading business partners to dental group practices. The Company is affiliated with 27 dental groups which have 242 dental facilities with approximately 2,097 operatories located in 18 states.

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: With the exception of the historical information contained in this news release, the matters described herein contain "forward-looking" statements that involve risk and uncertainties that may individually or collectively impact the matters herein described, including but not limited to the possibility that we may not realize the benefits expected from our acquisition and affiliation strategy, economic, regulatory and/or other factors outside the control of the Company, which are detailed from time to time in the "Risk Factors" section of the Company's SEC reports, including the annual report on Form 10-K for the year ended December 31, 2007.

Contacts: Gregory A. Serrao Chairman, President and Chief Executive Officer 781-224-0880 Breht T. Feigh Executive Vice President, Chief Financial Officer and Treasurer 781-224-0880 American Dental Partners, Inc. 401 Edgewater Drive, Suite 430 Wakefield, MA 01880 Phone: 781-224-0880 Fax: 781-224-4216