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Prospectus Supplement No. 2
Filed pursuant to Rule 424(b)(3)
File No. 333-56941
_______________________________
AMERICAN DENTAL PARTNERS, INC.
750,000 SHARES OF COMMON STOCK
AND
$25,000,000 AGGREGATE PRINCIPAL AMOUNT OF
SUBORDINATED PROMISSORY NOTES
September 23, 1999
_______________________________
This prospectus supplement relates to the prospectus dated May 28,
1999 (the "Prospectus"), as supplemented by the prospectus supplement dated
August 13, 1999, covering our offer and sale of up to 750,000 shares of our
Common Stock and up to $25,000,000 aggregate principal amount of our
Subordinated Promissory Notes which we may issue from time to time in connection
with future direct and indirect acquisition and affiliation transactions.
As of September 22, 1999, 679,878 shares of our Common Stock and
$22,015,000 of our Subordinated Promissory Notes remain available for issuance.
Recent Developments
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Since June 30, 1999, we have acquired substantially all the assets of
six dental practices and simultaneously entered into 40-year service agreements
with four of the affiliated dental groups. The dentists of the other two dental
practices joined existing affiliates in Pittsburgh and Houston. The six dental
practices are Kenneth P. Dick, D.M.D. in Johnstown, Pennsylvania; Gary R.
Christman, D.D.S. in Humble and Kingwood, Texas; and Riverside Dental Group,
Dental Associates of Riverside, Dental Associates of Moreno Valley and Dental
Associates of Corona in southern California. The aggregate purchase price paid
in connection with these transactions consisted of approximately $10.8 million
in cash, $1.7 million in Subordinated Promissory Notes and $0.2 million in
deferred payments.
In addition, we are currently in discussions with a number of dentists
and owners of dental group practices about possible affiliations with us. There
can be no assurance that we will consummate any of these possible affiliations.
_______________________________
Our Common Stock trades on the Nasdaq National Market under the symbol
"ADPI." On September 22, 1999, the last reported sale price of our Common Stock
was $9.875 per share.
INVESTING IN THE COMMON STOCK AND THE SUBORDINATED PROMISSORY NOTES
ISSUED UNDER THE PROSPECTUS AND THIS PROSPECTUS SUPPLEMENT INVOLVES RISK.
BEFORE MAKING ANY INVESTMENT IN OUR COMPANY, YOU SHOULD CONSIDER CAREFULLY THE
RISK FACTORS BEGINNING ON PAGE 7 OF THE PROSPECTUS.
NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE
SECURITIES COMMISSION HAS APPROVED ANY OF THE SECURITIES OFFERED BY THE
PROSPECTUS OR THIS PROSPECTUS SUPPLEMENT OR DETERMINED THAT THE PROSPECTUS OR
THIS PROSPECTUS SUPPLEMENT ARE ACCURATE OR COMPLETE. ANY REPRESENTATION TO THE
CONTRARY IS A CRIMINAL OFFENSE.
