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                                                                     EXHIBIT 4.3

                           CERTIFICATE OF DESIGNATION
                                       OF
                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK
                                       OF
                      ORTHODONTIC CENTERS OF AMERICA, INC.

                     Pursuant to Section 151 of the General
                    Corporation Law of the State of Delaware

         Orthodontic Centers of America, Inc., a Delaware corporation ("OCA"),
through the undersigned duly authorized officer, in accordance with the
provisions of Sections 103 and 151 of the General Corporation Law of the State
of Delaware, DOES HEREBY CERTIFY:

         That, the Board of Directors of OCA on March 3, 2004, pursuant to the
authority conferred upon the Board of Directors by the Restated Certificate of
Incorporation of OCA (the "Certificate of Incorporation") and in accordance with
the provisions of Section 151 of the General Corporation Law of the State of
Delaware, adopted the following resolution creating a series of Preferred Stock,
par value $.01 per share:

         RESOLVED, that, pursuant to the authority expressly granted to and
vested in the Board of Directors of OCA in accordance with the provisions of
Article 4(b) of the Restated Certificate of Incorporation, a series of 500,000
shares of the Preferred Stock of the Company, par value $.01 per share, be, and
it hereby is, created and that the voting powers, designations, preferences and
relative, participating, optional and other special rights of the shares of such
series, and the qualifications, limitations or restrictions thereof are as
follows:

SERIES A JUNIOR PARTICIPATING PREFERRED STOCK:

         (a)      DESIGNATION AND AMOUNT. The shares of such series shall be
designated as "Series A Junior Participating Preferred Stock" (the "Series A
Junior Preferred Stock") and the number of shares constituting the Series A
Junior Preferred Stock shall be 500,000. Such number of shares may be increased
or decreased by resolution of the Board of Directors; PROVIDED, that no decrease
shall reduce the number of shares of Series A Junior Preferred Stock to a number
less than the number of shares then outstanding plus the number of shares
reserved for issuance upon the exercise of outstanding options, rights or
warrants or upon the conversion of any outstanding securities issued by OCA
convertible into Series A Junior Preferred Stock.

         (b)      DIVIDENDS AND DISTRIBUTIONS.

                  (i)      Subject to the rights of the holders of any shares of
         any series of Preferred Stock (or any similar stock) ranking prior and
         superior to the Series A Junior Preferred Stock with respect to
         dividends, the holders of shares of Series A Junior Preferred Stock, in
         preference to the holders of Common Stock, $.01 par value per share
         (the "Common Stock"), of OCA, and of any other junior stock, shall be
         entitled to receive, when, as and if declared by the Board of Directors
         out of funds legally available for the purpose, quarterly dividends
         payable on the first business day of February, May, August and November
         in each year (each such date being referred to herein as a "Quarterly
         Dividend Payment Date") as provided in paragraphs (ii) and (iii) of
         this Section (b) in an amount per share (rounded to the nearest cent)
         equal to the greater of (A) $1.00 in cash or (B) subject to the
         provision for adjustment hereinafter set forth, 1,000 times the
         aggregate per share amount (payable in cash) of all cash dividends, and
         1,000 times the aggregate per share amount (payable in kind) of all
         non-cash dividends or other distributions, other than a dividend
         payable in shares of Common Stock or a subdivision of the outstanding
         shares of Common Stock (by reclassification or otherwise), declared on
         the Common Stock since the immediately preceding Quarterly Dividend
         Payment Date or with respect to the first Quarterly Dividend Payment
         Date, since the first issuance of any share or fraction of a share of
         Series A Junior Preferred Stock. If OCA shall at any time declare or
         pay any dividend on the Common Stock payable in shares of Common Stock,
         or effect a subdivision or combination or consolidation of the
         outstanding shares of Common Stock (by reclassification or otherwise)
         into a greater or lesser number of shares of Common Stock, then in each
         such

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         case the amount to which holders of shares of Series A Junior Preferred
         Stock were entitled immediately prior to such event under clause (B) of
         the preceding sentence shall be adjusted by multiplying such amount by
         a fraction, the numerator of which is the number of shares of Common
         Stock outstanding immediately after such event and the denominator of
         which is the number of shares of Common Stock that was outstanding
         immediately prior to such event.

                  (ii)     OCA shall declare a dividend or distribution on the
         Series A Junior Preferred Stock as provided in paragraph (i) of this
         Section (b) immediately after it declares a dividend or distribution on
         the Common Stock (other than a dividend payable in shares of Common
         Stock); PROVIDED that, if no dividend or distribution shall have been
         declared on the Common Stock during the period between any Quarterly
         Dividend Payment Date and the next subsequent Quarterly Dividend
         Payment Date, a dividend of $1.00 per share payable in cash on the
         Series A Junior Preferred Stock shall nevertheless accrue and be
         cumulative on the outstanding shares of Series A Junior Preferred Stock
         as provided in paragraph (iii) of this Section (b).

                  (iii)    Dividends shall begin to accrue and be cumulative on
         outstanding shares of Series A Junior Preferred Stock from the
         Quarterly Dividend Payment Date next preceding the date of issue of
         such shares, unless the date of issue of such shares is prior to the
         record date for the first Quarterly Dividend Payment Date, in which
         case dividends on such shares shall begin to accrue from the date of
         issue of such shares, or unless the date of issue is a Quarterly
         Dividend Payment Date or is a date after the record date for the
         determination of holders of shares of Series A Junior Preferred Stock
         entitled to receive a quarterly dividend and before such Quarterly
         Dividend Payment Date, in either of which events such dividends shall
         begin to accrue and be cumulative from such Quarterly Dividend Payment
         Date. Accrued but unpaid dividends shall not bear interest. Dividends
         paid on the shares of Series A Junior Preferred Stock in an amount less
         than the total amount of such dividends at the time accrued and payable
         on such shares shall be allocated pro rata on a share-by-share basis
         among all such shares at the time outstanding. The Board of Directors
         may fix a record date for the determination of holders of shares of
         Series A Junior Preferred Stock entitled to receive payment of a
         dividend or distribution declared thereon, which record date shall be
         not more than 60 days prior to the date fixed for the payment thereof.

         (c)      VOTING RIGHTS. The holders of shares of Series A Junior
Preferred Stock shall have the following voting rights:

                  (i)      Subject to the provisions for adjustment hereinafter
         set forth, each share of Series A Junior Preferred Stock shall entitle
         the holder thereof to 1,000 votes on all matters submitted to a vote of
         the stockholders of OCA. If OCA shall at any time declare or pay any
         dividend on Common Stock payable in shares of Common Stock, or effect a
         subdivision or combination of the outstanding shares of Common Stock
         (by reclassification or otherwise) into a greater or lesser number of
         shares of Common Stock, then in each such case the number of votes per
         share to which holders of shares of Series A Junior Preferred Stock
         were entitled immediately prior to such event shall be adjusted by
         multiplying such number by a fraction the numerator of which is the
         number of shares of Common Stock outstanding immediately after such
         event and the denominator of which is the number of shares of Common
         Stock that was outstanding immediately prior to such event.

                  (ii)     Except as otherwise provided herein, in the
         Certificate of Incorporation, as it may be amended from time to time,
         in any other Certificate of Designation creating a series of Preferred
         Stock or any similar stock, or by law, the holders of shares of Series
         A Junior Preferred Stock and the holders of shares of Common Stock and
         any other capital stock of OCA having general voting rights shall vote
         together as one class on all matters submitted to a vote of
         stockholders of OCA.

                  (iii)    Except as set forth herein or as otherwise provided
         by law, holders of Series A Junior Preferred Stock shall have no
         special voting rights and their consent shall not be required (except
         to the extent they are entitled to vote with holders of Common Stock as
         set forth herein) for taking any corporate action.



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         (d)      CERTAIN RESTRICTIONS.

                  (i)      Whenever quarterly dividends or other dividends or
         distributions payable on the Series A Junior Preferred Stock as
         provided in Section (b) are in arrears, thereafter and until all
         accrued and unpaid dividends and distributions, whether or not
         declared, on shares of Series A Junior Preferred Stock outstanding
         shall have been paid in full, or declared and a sum sufficient for the
         payment therefor be set apart for payment and be in the process of
         payment, OCA shall not:

                           (A)      declare or pay dividends, or make any other
                  distributions, on any shares of stock ranking junior (either
                  as to dividends or upon liquidation, dissolution or winding
                  up) to the Series A Junior Preferred Stock;

                           (B)      declare or pay dividends, or make any other
                  distributions, on any shares of stock ranking on a parity
                  (either as to dividends or upon liquidation, dissolution or
                  winding up) with the Series A Junior Preferred Stock, except
                  dividends paid ratably on the Series A Junior Preferred Stock
                  and all such parity stock on which dividends are payable or in
                  arrears in proportion to the total amounts to which the
                  holders of all such shares are then entitled;

                           (C)      redeem or purchase or otherwise acquire for
                  consideration shares of any stock ranking junior (either as to
                  dividends or upon liquidation, dissolution or winding up) to
                  the Series A Junior Preferred Stock, PROVIDED that OCA may at
                  any time redeem, purchase or otherwise acquire shares of any
                  such junior stock in exchange for shares of any stock of OCA
                  ranking junior (as to both dividends and upon dissolution,
                  liquidation or winding up) to the Series A Junior Preferred
                  Stock; or

                           (D)      redeem or purchase or otherwise acquire for
                  consideration any shares of Series A Junior Preferred Stock or
                  any shares of stock ranking on a parity (either as to
                  dividends or upon liquidation, dissolution or winding up) with
                  the Series A Junior Preferred Stock, except in accordance with
                  a purchase offer made in writing or by publication (as
                  determined by the Board of Directors) to all holders of such
                  shares upon such terms as the Board of Directors, after
                  consideration of the respective annual dividend rates and
                  other relative rights and preferences of the respective series
                  and classes, shall determine in good faith will result in fair
                  and equitable treatment among the holders of the respective
                  series or classes.

                  (ii)     OCA shall not permit any subsidiary of OCA to
         purchase or otherwise acquire for consideration any shares of stock of
         OCA unless OCA could, under paragraph (i) of this Section (d), purchase
         or otherwise acquire such shares at such time and in such manner.

         (e)      REACQUIRED SHARES. Any shares of Series A Junior Preferred
Stock purchased or otherwise acquired by OCA in any manner whatsoever shall be
retired and canceled promptly after the acquisition thereof. All such shares
shall upon their cancellation become authorized but unissued shares of Preferred
Stock and may be reissued as part of a new series of Preferred Stock subject to
the conditions and restrictions on issuance set forth herein, in the Certificate
of Incorporation, or in any other Certificate of Designation creating a series
of Preferred Stock or any similar stock or as otherwise required by law.

         (f)      LIQUIDATION, DISSOLUTION OR WINDING UP. Upon any liquidation,
dissolution or winding up of OCA, no distribution shall be made (i) to the
holders of shares of stock ranking junior (either as to dividends or as to
amounts payable upon liquidation, dissolution or winding up) to the Series A
Junior Preferred Stock unless, prior thereto, the holders of Series A Junior
Preferred Stock shall have received an amount per share (rounded to the nearest
cent) equal to the greater of (A) $1,000 per share, or (B) an amount per share,
subject to the provision for adjustment hereinafter set forth, equal to 1,000
times the aggregate amount to be distributed per share to holders of Common
Stock, plus, in either case, an amount equal to accrued and unpaid dividends and
distributions thereon, whether or not declared, to the date of such payment, or
(ii) to the holders of stock ranking on a parity (either as to dividends or as
to amounts payable upon liquidation, dissolution or winding up) with the Series
A Junior Preferred Stock, except distributions made ratably on the Series A
Junior Preferred Stock and all such parity stock in proportion to the total
amounts to which the holders of all such Shares are entitled upon such
liquidation, dissolution or winding up. If OCA shall at any time declare or pay
any dividend on Common Stock payable in shares of Common Stock, or effect a
subdivision or combination or consolidation of the outstanding shares of Common
Stock (by reclassification or otherwise) into a greater or lesser number of
shares of Common Stock, then in


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each such case the aggregate amount to which holders of shares of Series A
Junior Preferred Stock were entitled immediately prior to such event under the
proviso in clause (i)(B) of the preceding sentence shall be adjusted by
multiplying such amount by a fraction the numerator of which is the number of
shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that was
outstanding immediately prior to such event.

         (g)      CONSOLIDATION, MERGER, ETC. If OCA shall enter into any
consolidation, merger, combination or other transaction in which the shares of
Common Stock are exchanged for or changed into other stock or securities, cash
or any other property, or any combination thereof, then in any such case each
share of Series A Junior Preferred Stock shall at the same time be similarly
exchanged or changed into an amount per share, subject to the provision for
adjustment hereinafter set forth, equal to 1,000 times the aggregate amount of
stock, securities, cash or any other property (payable in kind), or any
combination thereof, as the case may be, into which or for which each share of
Common Stock is changed or exchanged. If OCA shall at any time declare or pay
any dividend on the Common Stock payable in shares of Common Stock, or effect a
subdivision or combination or consolidation of the outstanding shares of Common
Stock (by reclassification or otherwise) into a greater or lesser number of
shares of Common Stock, then in each such case the amount set forth in the
preceding sentence with respect to the exchange or change of shares of Series A
Junior Preferred Stock shall be adjusted by multiplying such amount by a
fraction, the numerator of which is the number of shares of Common Stock
outstanding immediately after such event and the denominator of which is the
number of shares of Common Stock that was outstanding immediately prior to such
event.

         (h)      REDEMPTION. The shares of Series A Junior Preferred Stock
shall not be redeemable. So long as any shares of Series A Junior Preferred
Stock remain outstanding, OCA shall not purchase or otherwise acquire for
consideration any shares of stock ranking junior (either as to dividends or upon
liquidation, dissolution or winding up) to the Series A Junior Preferred Stock
unless OCA shall substantially concurrently also purchase or acquire for
consideration a proportionate number of shares of Series A Junior Preferred
Stock.

         (i)      RANK. The Series A Junior Preferred Stock shall rank, with
respect to payment of dividends and the distribution of assets, junior to all
series of any other class of OCA's Preferred Stock; provided that any class or
series of OCA's Preferred Stock hereafter created may expressly provide that
such class or series shall be pari passu with the Series A Preferred Stock with
respect to the payment of dividends and distributions, voting rights and/or
distributions upon liquidation, dissolution or winding up of OCA.

         (j)      AMENDMENT. The Certificate of Incorporation of OCA shall not
be amended in any manner which would materially alter or change the powers,
preferences, privileges or special rights of the Series A Junior Preferred Stock
so as to affect them adversely without the affirmative vote of the holders of at
least two-thirds of the outstanding shares of Series A Junior Preferred Stock,
voting together as a single class.

         IN WITNESS WHEREOF, this Certificate of Designation is executed on
behalf of OCA by its Chairman of the Board, President and Chief Executive
Officer, and attested by its Secretary, this 3rd day of March, 2004.

                             ORTHODONTIC CENTERS OF AMERICA, INC.

                             By: /s/ Bartholomew F. Palmisano, Sr.
                                 -------------------------------------------
                                 Bartholomew F. Palmisano, Sr.
                                 Chairman of the Board, President and
                                  Chief Executive Officer

ATTEST:

/s/ Bartholomew F. Palmisano, Jr.
-----------------------------------
Bartholomew F. Palmisano, Jr.
Secretary


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