Notice is hereby given that a class action lawsuit was filed in the United States District Court for the District of Massachusetts on behalf of all purchasers of securities of American Dental Partners, Inc. ("ADPI" or the "Company") between August 10 2005 through December 13, 2007, inclusive (the "Class Period").

If you wish to discuss this action or have any questions concerning this notice or your rights or interests with respect to these matters, please contact Schiffrin Barroway Topaz & Kessler, LLP (Darren J. Check, Esq. or Richard A. Maniskas, Esq.) toll free at 1-888-299-7706 or 1-610-667-7706, or via e-mail at info@sbtklaw.com.

The Complaint charges ADPI and certain of its officers and directors with violations of the Securities Exchange Act of 1934. ADPI is a business partner and provider of services to dental group practices. More specifically, the Complaint alleges that the Company failed to disclose and misrepresented the following material adverse facts which were known to defendants or recklessly disregarded by them: (1) that the Company engaged in tortious and unlawful conduct towards Park Dental Group ("PDG"); (2) that as a result of this conduct, the Company booked a large portion of earnings and revenue which materially inflated financial figures; (3) that the Company's financial statements were not prepared in accordance with Generally Accepted Accounting Principles; (4) that the Company lacked adequate internal and financial controls; and (5) that, as a result of the foregoing, the Company's financial statements were materially false and misleading at all relevant times.

Beginning on January 1, 1999, ADPI subsidiary PDHC, Ltd. ("PDHC") entered into a Service Agreement (the "Service Agreement") with PDG. The Service Agreement was amended January 1, 2001 and again on August 10, 2005. According to the Company's financial statements, the relationship with PDG accounted for approximately 30% of the Company's consolidated net revenue between 2004 and 2006. No other customer of ADPI accounted for more than 10% of the Company's consolidated net revenue.

On December 12, 2007, investors were shocked to learn that a judgment had been awarded in favor of PDG, against PDHC and ADPI. The jury in the case awarded PDG $88,290,647 in damages, broken down as follows: $9,413,397 in compensatory damages for breach of the Service Agreement; $11,500,000 for breach of implied covenants of good faith and fair dealing; $200,000 for breach of fiduciary duty; $67,000,000 for tortious interference with contract or prospective advantage; and $177,250 for defamation. Upon the release of this news, the Company's shares declined $5.36 per share, or 27.21 percent, to close on December 12, 2007 at $14.34 per share, on unusually heavy trading volume.

The following day, as the public continued to learn of the December 12, 2007 judgment against ADPI, investors were further shocked and appalled to learn that due to ADPI's egregious conduct and actions, the jury had awarded PDG $42,250,000 in punitive damages. Upon the release of this news, the Company's shares declined $9.72 per share, or 67.78 percent, to close on December 13, 2007 at $4.62 per share, on unusually heavy trading volume.

Plaintiff seeks to recover damages on behalf of class members and is represented by the law firm of Schiffrin Barroway Topaz & Kessler which prosecutes class actions in both state and federal courts throughout the country. Schiffrin Barroway Topaz & Kessler is a driving force behind corporate governance reform, and has recovered billions of dollars on behalf of institutional and individual investors from the United States and around the world.

For more information about Schiffrin Barroway Topaz & Kessler or to sign up to participate in this action online, please visit www.sbtklaw.com

If you are a member of the class described above, you may, not later than March 31, 2008, move the Court to serve as lead plaintiff of the class, if you so choose. A lead plaintiff is a representative party that acts on behalf of other class members in directing the litigation. In order to be appointed lead plaintiff, the Court must determine that the class member's claim is typical of the claims of other class members, and that the class member will adequately represent the class. Your ability to share in any recovery is not, however, affected by the decision whether or not to serve as a lead plaintiff. Any member of the purported class may move the court to serve as lead plaintiff through counsel of their choice, or may choose to do nothing and remain an absent class member.