Exhibit 10(mmm)

FIRST AMENDMENT TO

AMENDED AND RESTATED EMPLOYMENT

AND NON-COMPETITION AGREEMENT

This amendment is made effective January 1, 2009, between Gregory A. Serrao (the
“Executive”) and American Dental Partners, Inc., a Delaware corporation (the
“Company”).

Background Information

A. The Executive and the Company (the “Parties”) are parties to an Amended and
Restated Employment and Non-Competition Agreement dated January 2, 2001 (the
“Agreement”).

B. The Parties desire to modify the Agreement to cause it to comply with the
final regulations promulgated under Section 409A of the Internal Revenue Code of
1986, as amended (the “Code”), which governs non-qualified deferred compensation
arrangements, and the Parties are entering into this amendment for that purpose.

Statement of the Agreement

The Parties hereby acknowledge the foregoing Background Information and agree as
follows:

1. Definitions. Any capitalized terms used but not otherwise defined in this
amendment shall have the respective meanings given those terms in the Agreement.

2. Bonus Payments. The last sentence in Section 5 of the Agreement is hereby
amended to read in its entirety as follows:

Each bonus payable to the Executive under the Bonus Plan, if any, shall be paid
not later than the first to occur of (i) 10 days after receipt of the audited
financial statements for the applicable fiscal year or (ii) the date which is 75
days after the end of such fiscal year; provided that in no event shall such
payment be made later than December 31 following the 75-day period after such
applicable fiscal year.

3. Benefits. A new last sentence is hereby added to the end of Sections 6.02 and
6.06 of the Agreement to read as follows:

If any such benefits are taxable, the Company shall ensure that terms of the
benefits will comply with Section 409A of the Code (“Section 409A”) and the
Treasury Regulations and other guidance promulgated or issued thereunder.

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4. Reimbursement of Expenses. A new last sentence is hereby added to the end of
Section 6.03 to read as follows:

Such reimbursement shall occur no later than the end of the calendar year
following the calendar year in which such expense was incurred.

5. Post-Termination Payments. New Sections 8.06, 8.07, and 8.08 are hereby added
to the Agreement to read in their entirety as follows:

Section 8.06. Specified Employee Delay. If at the time of termination of his
employment with the Company the Executive is a “specified employee” as defined
in Section 409A, any payments under this Agreement due to a separation from
service (as defined in Section 409A) and subject to Section 409A shall be
delayed until the first business day of the seventh calendar month following the
date of separation from service, or, if earlier, the date of death of the
Executive (in either case, the “Payment Date”). Payments which are delayed
pursuant to the preceding sentence (the “Delayed Payments”) shall be accumulated
and paid on the Payment Date. In addition, on the Payment Date, the Company
shall pay the Executive interest on each Delayed Payment, accrued from the
original date such payment otherwise would have been payable but for the first
sentence of this Section 8.06 (the “Original Payment Date”) to the Payment Date,
at a rate equal to the U.S. prime rate of interest, as published by The Wall
Street Journal, in effect on the Original Payment Date.

Section 8.07. Payments for Taxes. In accordance with Section 409A and the
regulations issued thereunder, this Agreement shall permit the payment of
amounts necessary to (a) satisfy the employment tax withholding obligations that
arise under this Agreement prior to the date that payment may otherwise be made
under this Agreement and/or (b) satisfy the excise tax or underpayment penalties
owed under Section 409A in the event of a violation of Section 409A under this
Agreement.

Section 8.08. Effect of Dispute. In the event of a genuine dispute between the
Company and the Executive regarding the amount or timing of benefits under this
Agreement, a delay in the payment of amounts under this Agreement shall not
cause the Executive to violate Section 409A to the extent such delay satisfies
the conditions set forth in Section 409A and applicable regulations thereunder.

6. Interpretation. In the event of any inconsistency between the provisions of
the Agreement and this amendment, the provisions of this amendment shall
control. Except as modified by this amendment, the Agreement shall continue in
full force and effect. The headings of the various sections of this amendment
are not part of the context of this amendment, are merely labels to assist in
locating those sections, and shall be ignored in construing this amendment.

 

    AMERICAN DENTAL PARTNERS, INC. /s/ Gregory A. Serrao     /s/ Breht T. Feigh
GREGORY A. SERRAO     Breht T. Feigh, Chief Financial Officer

 

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