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                                                                   EXHIBIT 10.43
                                                                (CONFORMED COPY)
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                            UNITED DENTAL CARE, INC.
                             STOCK OPTION AGREEMENT

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        THIS STOCK OPTION AGREEMENT ("Agreement") made as of December 17, 1997 
and amended as of March 26, 1998 between United Dental Care, Inc. (the
"Company"), a Delaware corporation, and Robert J. Nettinga ("Optionee"), a
director of the Company.

        NOW, THEREFORE, in consideration of the premises and the mutual 
covenants hereinafter set forth and for other good and valuable consideration,
the parties hereto agree as follows:
           
        1. Grant of Option.  The Company hereby grants to the Optionee a stock 
option (the "Option") to purchase, subject to and upon the terms and conditions
hereinafter set forth, 12,000 shares of the Common Stock, $.10 par value, of
the Company. The date of this Agreement is the date of the grant of this
Option.

        2. Purchase Price.  Subject to Section 9 hereof, the purchase price of 
the Common Stock subject to the Option shall be $11.25 per share (the "Option
Price").

        3. Time to Exercise.  This Option shall vest and be exercisable in 
installments as follows:


<TABLE>
<S>                                                                             <C>
          (a)Upon the re-election of the Optionee as a Director of the                      
             Company at its Annual Meeting held in 1999                         3,000 shares
          (b)Upon the re-election of the Optionee as a Director of the                      
             Company at its Annual Meeting held in 2000                         3,000 shares
          (c)Upon the re-election of the Optionee as a Director of the
             Company at its Annual Meeting held in 2001                         3,000 shares
          (d)Upon the e-election of the Optionee as a Director of the
             Company at its Annual Meeting held on 2002                         3,000 shares

</TABLE>

        To the extent not exercised, installments shall accumulate and be
exercisable, in whole or in part, in any subsequent period.  Anything in this
Agreement to the contrary notwithstanding, this Option shall terminate and no
part of the Option may be exercised after 5:00 p.m. on December 17, 2007.

        4.Term.

          (a)   If the Optionee shall die while he is a director of the Company
                holding the Option granted under Section 1 hereof, the Executor
                or Administrator of the Optionee's
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                                                                   EXHIBIT 10.43

                estate or the person or persons acquiring the Option upon the
                death of the Optionee may exercise such Option (to the extent
                that the Optionee shall have been entitled to do so on the date
                of his death) at any time within one (1) year after the
                Optionee's death, subject to the other terms and conditions of
                the Plan and this Agreement, and any remaining portion of such
                Option not exercisable by the Optionee on the date of his death
                shall terminate immediately and cease to exist; provided,
                however, that no Option shall be exercisable after the time set
                forth in the last sentence of Section 3 hereof.

         (b)    If the Optionee shall hereafter cease for any reason (other
                than death, which shall be governed by Section 4(a) hereof) to
                be a director of the Company, then the Option shall terminate
                on the effective date of such termination as to any unexercised
                portion thereof.

         5.   Restrictions on Exercise.  The Option may not be exercised and no
certificates representing shares subject to such Option shall be delivered if
any requisite approval or consent of any governmental authority of any kind
having jurisdiction over the exercise of Options shall not have been secured.
The Option may only be exercised with respect to full shares and not for any
fractional shares.

         6.   Manner of Exercise.  Subject to such administrative regulations
as the Committee administering the Plan may from time to time adopt, the
Optionee shall exercise the option by giving written notice to the Company of
the number of shares being purchased and the Option Price to be paid therefor
accompanied by the following:

          (a)   full payment in cash of the Option Price; provided, however
                that in lieu of cash an Optionee may, upon approval by the
                Committee exercise his Option by tendering to the Company
                shares of the Common Stock of the Company owned by him having a
                fair market value equal to the cash Option Price, or, by a
                combination of both cash and stock;

          (b)   an undertaking to furnish or execute such documents as the
                Company in its discretion shall deem necessary (1) to evidence
                the exercise, in whole or in part, of the Option evidenced by
                this Agreement, (2) to determine whether registration is then
                required under the Securities Act of 1933, as then in effect,
                under (3) to comply with or satisfy the requirements of the
                Securities Act of 1933, or any other law, as then in effect and
                (4) to notify the Company in writing of any disposition made of
                any shares issued pursuant to the exercise of the Option
                evidenced by this Agreement within a period of thirty (30) days
                after the day of the transfer of any such shares by the
                Optionee.

         7.   Non-Assignability.  This Option is not assignable or transferable
by Optionee except by will or by the laws of descent and distribution.
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                                                                   EXHIBIT 10.43

         8.          Rights as Stockholder.  The Optionee shall have no
rights as a stockholder with respect to any shares covered by the Option
evidenced by this Agreement until the issuance of one or more certificates to
him for such shares upon due exercise of the Option. Except as provided in
Section 9, no adjustment shall be made for dividends or other rights for which
the record date is prior to the issuance of certificates.

         9.    Capital Adjustments.  The number of shares of Common Stock
covered by the unexercised portion of the Option evidenced by this Agreement,
and in the Option Price thereof, shall be subject to such adjustment as
appropriate or necessary to reflect any stock dividend, stock split, reverse
stock split, share combination, exchange of shares, recapitalization,
reclassification, merger, consolidation, separation, reorganization,
liquidation or the like of or by the Company, so that the rights of the holder
hereof shall remain proportionate to the rights held hereunder immediately
prior to such event.

         10.  Acceleration Upon Change In Control.  In the event of a Change In
Control (as defined below) of the Company, then the holder of the options
evidenced by this Agreement shall have the right, immediately prior to the
consummation of such transaction constituting the Change In Control, to
exercise such options, to the extent not theretofore exercised, without regard
to any of the requirements as to the time periods and installments of
exercisability set forth in this Agreement if (and only if) such options have
not expired or otherwise been terminated prior to such vesting and the date of
such transaction.  Notwithstanding the foregoing, such acceleration of
exercisability shall not apply if a majority of the board of directors of the
acquiring or surviving corporation (or a parent corporation thereof)
immediately after such Change in Control transaction consists of individuals
who constitute a majority of the board of directors of the Company immediately
prior to such transaction and such surviving or acquiring corporation agrees to
assume such options in connection with such transaction.

         A Change of Control" means (a) the acquisition by any individual,
entity or group (within the meaning of Section 12(d)(3) or 14 (d)(2) of the
Exchange Act) (an "Acquiring Person") of beneficial ownership (within the
meaning of the rule 13d-e promulgated under the Exchange Act) of 50% or more of
either (i) the then outstanding shares of Common Stock of the Corporation (the
"Outstanding Corporation common stock") or (ii) the combined voting power of
the then outstanding voting securities of the Corporation entitled to vote
generally in the election of directors (the "Outstanding Corporation Voting
Securities"); (b) individuals who, as of the date hereof, constitute the Board
(the Incumbent Board) cease for any reason to constitute at least a majority of
the Board; provided, however, that any individual becoming a director
subsequent to the date hereof, whose election, or nomination for election by
the Corporations shareholders, was approved by a vote of at least a majority of
the directors then comprising the Incumbent Board shall be considered as though
such individual were a member of the Incumbent Board, but excluding, for this
purpose, any such individual whose initial assumption of office occurs as a
result of an actual or threatened election contest with respect to the election
or removal of directors or other actual or threatened solicitation of proxies
or consents by or on behalf of an Acquiring Person other than the Board; or (c)
approval by the shareholders of the Corporation of a complete liquidation or
dissolution of the Corporation.
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                                                                   EXHIBIT 10.43

         In addition to the foregoing, in the event a Change In Control
transaction occurs and the options evidenced by this Agreement become subject
to such acceleration of exercisability but the holder of such options elects
not to exercise such options, all such options shall terminate upon
consummation of such Change In Control transaction.

         11.  Investment Purpose.  This Option is granted on the condition that
the purchases of Common Stock thereunder shall be for investment purposes, and
not with a view to resale or distribution except that in the event the Common
Stock subject to such Option is registered under the Securities Act of 1933, as
amended, or in the event a resale of such stock without such registration would
otherwise be permissible such condition shall be inoperative if in the opinion
of counsel for the Company such condition is not required under the Securities
Act of 1933 or  regulation, or rule of any governmental agency.

         12.  Law Governing.  This Agreement is intended to be performed in the
State of Texas and shall be construed and enforced in accordance with and
governed by the laws of the State of Texas.

         13.  Binding Effect.  This Agreement shall insure to the benefit of
and be binding upon the parties hereto and their personal representatives,
successors, heirs, and assigns.

         14.  Defined Terms.  Certain capitalized terms used herein have the
              meanings as set forth in the Plan.

         IN WITNESS WHEREOF, the Company has caused this Agreement to be signed
by its duly authorized officer and the Optionee has duly signed this Agreement
on the day and year first above written.



                                             Robert J. Nettinga                
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                                 OPTIONEE
                                 
                                 
                                 
                                 UNITED DENTAL CARE, INC.
                                 
                                 
                                 
                                                William H. Wilcox              
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                                 William H. Wilcox
                                 Chief Executive Officer