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                                                                    EXHIBIT 10.8

                      ORTHODONTIC CENTERS OF AMERICA, INC.

                            PARTICIPATION AGREEMENT




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                                                                    EXHIBIT 10.8


                      ORTHODONTIC CENTERS OF AMERICA, INC.

                             PARTICIPATION AGREEMENT


         This Participation Agreement ("Agreement") is made and entered into as
of ______________, 2001, by and between Orthodontic Centers of America, Inc., a
Delaware corporation ("OCA"), and _______________________, an individual
residing in the State of ______________ (the "Participant").

                                    RECITALS:

         WHEREAS, OCA adopted the Programs (as defined below) through
resolutions adopted by OCA's Board of Directors; and

         WHEREAS, the Participant desires to participate in the Programs,
subject to the terms and conditions therein and herein;

         NOW, THEREFORE, in consideration of the mutual covenants contained in
this agreement, the parties agree as follows:

                                   AGREEMENT:

1. Election to Participate. The Participant hereby elects to participate in (i)
the Orthodontic Centers of America, Inc. Stock Pool Program, (ii) the
Orthodontic Centers of America, Inc. Target Stock Program, (iii) the Orthodontic
Centers of America, Inc. OrthAlliance Stockholder Bonus Program, (iv) the
Orthodontic Centers of America, Inc. High Participation Bonus Program, (v) the
Orthodontic Centers of America, Inc. OrthAlliance Stockholder Value Program,
(vi) the Orthodontic Centers of America, Inc. Conversion Incentive Program, and
(vii) the Orthodontic Centers of America, Inc. Doctors Trust Program
(collectively, the "Programs"), in accordance with and subject to all of the
terms, conditions and provisions of each such Program and this Agreement, as
such may be amended from time to time. OCA hereby permits the Participant to
participate in the Programs (subject to the Participant's fulfillment and
compliance with all of the criteria for participation specified in each such
Program), as and to the extent provided in each such Program and on the terms,
conditions and provisions specified therein and herein, as such may be amended
from time to time.

2. Qualification to Participate. The Participant represents and warrants to OCA
that the Participant has, along with his or her respective OrthAlliance
Affiliated PC (as defined in the Programs), executed and delivered to
OrthAlliance their respective (i) Amendments (as defined in the Programs) and/or
(ii) OCA Business Services Agreement (as defined in the Programs), as
applicable, on the date(s) specified on Schedule 1 hereto. The Participant
further represents and warrants to OCA that he or she is an OrthAlliance
Affiliated Practitioner (as defined in the Programs). The Participant also
represents and warrants to OCA that the execution, delivery and performance of
this Agreement by the Participant has been duly authorized by all necessary
laws, resolutions and corporate action, and that this Agreement constitutes the
valid and enforceable obligations of the Participant in accordance with its
terms.




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3. Program Document Controls. The Participant acknowledges and agrees that his
or her participation in the Programs, and any and all awards, grants, shares or
rights granted or awarded to the Participant under any of the Programs, will be
governed by and subject to all of the terms, conditions, and provisions of this
Agreement and the relevant Program, as such exist on the date of this Agreement
and as such may be amended from time to time hereafter. A copy of each of the
Programs, as it exists on the date hereof, has been and/or is being provided or
made available to the Participant, and the Participant hereby acknowledges the
receipt thereof. In the event of any conflict between the provisions of this
Agreement and the provisions of any of the Programs, the terms of such Program,
as such may be amended, shall control, except as expressly stated otherwise
therein.

4. Notice. Whenever any notice is required or permitted hereunder, such notice
must be in writing and personally delivered or sent by mail or a delivery
service that is approved by OCA. Any notice required or permitted to be
delivered hereunder shall be deemed to be delivered on the date which it is
personally delivered, or, whether actually received or not, on the third
business day after it is deposited in the United States mail, certified or
registered, postage prepaid, return receipt requested, addressed to the person
who is to receive it at the address identified in this Section. OCA or the
Participant may change, by written notice to the other, the address specified
for receiving notices. Notices to OCA shall be addressed as follows:

                                    Orthodontic Centers of America, Inc.
                                    3850 N. Causeway Boulevard
                                    Suite 1040
                                    Metairie, Louisiana  70002
                                    Attention: Bartholomew F. Palmisano, Jr.

Notices to the Participant shall be hand delivered to the Participant on the
premises of OCA or its subsidiaries, or addressed to the latest address shown on
the records of OCA.

5. Information Confidential. As partial consideration for the Participant's
participation in the Programs, the Participant agrees that he or she will keep
confidential all information and knowledge that the Participant has relating to
the manner and amount of his or her participation in the Programs; provided,
however, that such information may be disclosed as required by law and may be
given in confidence to the Participant's spouse, tax and financial advisors, or
to a financial institution to the extent that such information is necessary to
secure a loan.

6. No Assignment. The Participant may not assign or transfer this Agreement, any
of his or her rights hereunder, his or her participation in any of the Programs
nor, except as provided in the Programs, any of his or her rights, benefits or
awards under any of the Programs.

7. Miscellaneous. This Agreement shall be construed and interpreted according to
the laws of the State of Louisiana, without regard to the principles of
conflicts of law thereof. This Agreement (together with the Programs) contains
the entire and only agreement between the parties respecting the subject matter
hereof. The headings of the various sections of this Agreement are for
convenience of reference only, and shall not modify, define, limit or expand the
express provisions of this Agreement. This Agreement shall be binding upon and
inure to the benefit of any successor or successors of OCA. This Agreement may
be executed in any number of counterparts and by the different parties hereto on
separate counterparts, each of which when executed and delivered shall be deemed
an original effective for binding the parties hereto, but all of which shall
together constitute one and the same instrument.



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         IN WITNESS WHEREOF, OCA has caused this Agreement to be executed and
the Participant has set his hand hereto on the day and year first written above.



                                            ORTHODONTIC CENTERS OF AMERICA, INC.



                                            By:
                                               ---------------------------------
                                            Name:
                                            Title:



                                            "PARTICIPANT"



                                            ------------------------------------
                                            Name:




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