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                                                                        EXH. 4.3


                               ORTHALLIANCE, INC.
                       1999 ORTHODONTIST STOCK OPTION PLAN

ARTICLE I.     DEFINITIONS

        As used herein, the following terms have the following meanings unless
the context clearly indicates to the contrary:

        1.1 "Allied Orthodontist" shall mean an orthodontist or dentist who (i)
holds an equity interest in an Allied Practice, or (ii) is a party to an
existing employment agreement with an Allied Practice.

        1.2 "Allied Practice" shall mean a professional business entity that
provides orthodontic or dental services to the public and is a party to an
existing (i) service agreement or (ii) consulting and business services
agreement with the Company or a subsidiary, whereby the Company or a subsidiary
provides management or consulting services to such entity in exchange for a
service or consulting fee.

        1.3 "Board" shall mean the Board of Directors of the Company.

        1.4 "Change in Control" shall mean the occurrence of any of the
following events:

               (a) a reorganization, merger or consolidation of the Company with
        one or more other corporations (except with respect to a transaction in
        which the sole purpose is to change the domicile or name of the
        Company), as a result of which the Company ceases to exist or becomes a
        subsidiary of another corporation (which shall be deemed to have
        occurred if another corporation shall own, directly or indirectly, more
        than fifty percent (50%) of the aggregate voting power of all
        outstanding equity securities of the Company);

               (b) a sale of all or substantially all of the Company's assets;
          or

               (c) Any "person" (as such term is used in Sections 13(d) and
        14(d) of the Exchange Act), other than any person who is a stockholder
        of the Company on or before the effective date of the Plan, by the
        acquisition or aggregation of securities is or becomes the beneficial
        owner, directly or indirectly, of securities of the Company representing
        fifty percent (50%) or more of the combined voting power of the
        Company's then outstanding securities ordinarily (and apart from rights
        accruing under special circumstances) having the right to vote at
        elections of directors (the "Base Capital Stock"); except that any
        change in the relative beneficial ownership of the Company's securities
        by any person resulting solely from a reduction in the aggregate number
        of outstanding shares of Base Capital Stock, and any decrease thereafter
        in such person's ownership of securities, shall be disregarded until
        such person increases in any manner, directly or indirectly, such
        person's beneficial ownership of any securities of the Company.

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        1.5. "Code" shall mean the Internal Revenue Code of 1986, as amended,
including effective date and transition rules (whether or not codified). Any
reference herein to a specific section of the Code shall be deemed to include a
reference to any applicable corresponding provision of future law.

        1.6 "Committee" shall mean a committee of at least two (2) Directors
appointed from time to time by the Board, having the duties and authority set
forth herein in addition to any other authority granted by the Board, provided,
however, that with respect to any Options granted to an individual who is also a
Section 16 Insider, the Committee shall consist of at least two (2) Directors
who are Non-Employee Directors (within the meaning of Rule 16b-3). At any time
that the Board shall not have appointed a committee as described above, any
reference herein to the Committee shall mean a reference to the Board.

        1.7    "Company" shall mean OrthAlliance, Inc., a Delaware corporation.

        1.8 "Director" shall mean a member of the Board and any person who is an
advisory, honorary or emeritus director of the Company if such person is
considered a director for the purposes of Section 16 of the Exchange Act, as
determined by reference to such Section 16 and to the rules, regulations,
judicial decisions, and interpretative or "no-action" positions with respect
thereto of the Securities and Exchange Commission, as the same may be in effect
or set forth from time to time.

        1.9 "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended. Any reference herein to a specific section of the Exchange Act shall be
deemed to include a reference to any applicable corresponding provision of
future law.

        1.10 "Exercise Price" shall mean the price at which an Optionee may
purchase a share of Stock under a Stock Option Agreement.

        1.11 "Fair Market Value" on any date shall mean (i) the average closing
sales price of the Stock for the immediately preceding five (5) trading days;
(ii) if the Stock is not traded on any national securities exchange, the average
of the closing high bid and low asked prices of the Stock on the Nasdaq National
Market or other over-the-counter market on the date such value is to be
determined, or in the absence of closing bids on such date, the closing bids on
the next preceding date on which there were bids; or (iii) if the Stock is not
traded on a national securities exchange or the over-the-counter market, the
fair market value as determined in good faith by the Board or the Committee
based on such relevant facts as may be available, including, without limitation,
the price at which recent sales of Stock have been made, the book value of the
Stock and the Company's current and future earnings.

        1.12 "Officer" shall mean a person who constitutes an officer of the
Company for the purposes of Section 16 of the Exchange Act, as determined by
reference to such Section 16 and to the rules, regulations, judicial decisions,
and interpretative or "no-action" positions with respect thereto of the
Securities and Exchange


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Commission, as the same may be in effect or set forth from time to time.

        1.13 "Option" shall mean an option to purchase Stock granted pursuant to
the provisions of Article VI hereof.

        1.14 "Optionee" shall mean an Allied Orthodontist to whom an Option has
been granted hereunder or their permitted assign.

        1.15 "Plan" shall mean the OrthAlliance, Inc. 1999 Orthodontist Stock
Option Plan, the terms of which are set forth herein.

        1.16 "Section 16 Insider" shall mean any person who is subject to the
provisions of Section 16 of the Exchange Act.

        1.17 "Stock" shall mean the Class A Common Stock, $.001 par value per
share, of the Company, subject to applicable provisions of Section 5.2.

        1.18 "Stock Option Agreement" shall mean a written agreement between the
Company and an Optionee under which the Optionee may purchase Stock hereunder,
as provided in Article VI hereof.

        1.19 "Subsidiary" shall mean any corporation in which the Company
directly or indirectly owns stock possessing fifty percent (50%) or more of the
total combined voting power of all classes of stock of such corporation.

ARTICLE II.    THE PLAN

        2.1. Name. This Plan shall be known as the "OrthAlliance, Inc. 1999
Orthodontist Stock Option Plan."

        2.2 Purpose. The purpose of the Plan is to advance the interests of the
Company, its Subsidiaries and its stockholders by affording certain Allied
Orthodontists an opportunity to acquire or increase their proprietary interests
in the Company. The objective of the Options is to promote the growth and
profitability of the Company and its Subsidiaries by providing Allied
Orthodontists with an additional incentive to achieve the Company's objectives
through participation in its success and growth.

        2.3. Effective Date. The effective date of this Plan is December 30,
1999.

ARTICLE III. PARTICIPANTS

        The Allied Orthodontists listed on Schedule A to this Plan shall be
eligible to participate in the Plan. Participation by other Allied Orthodontists
shall be as determined by the Committee, in its sole discretion.

ARTICLE IV. ADMINISTRATION

        4.1 Duties and Powers of the Committee. This Plan shall be administered
by the Committee. The Committee shall hold its meetings at such times and places
as it may determine and shall keep minutes of



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such meetings. The Committee shall make such rules and regulations for the
conduct of its business as it may deem necessary. The Committee shall have the
power to act by unanimous written consent in lieu of a meeting, and to meet
telephonically. In administering this Plan, the Committee's actions and
determinations shall be binding on all interested parties. Only the Committee
shall have the power to grant Options in accordance with the provisions of this
Plan. Subject to the provisions of this Plan, the Committee shall have the
discretion and authority to determine those Allied Orthodontists to whom Options
will be granted, the number of shares of Stock subject to each Option, such
other matters as are specified herein, and any other terms and conditions of a
Stock Option Agreement. To the extent not inconsistent with the provisions of
this Plan, the Committee may give an Optionee an election to surrender an Option
in exchange for the grant of a new Option, and shall have the authority to amend
or modify an outstanding Stock Option Agreement or to waive any provision
thereof, provided that the Optionee consents to such action.

        4.2 Interpretation; Rules. Subject to the express provisions of the
Plan, the Committee shall have complete authority to interpret the Plan, to
prescribe, amend and rescind rules and regulations relating to it, to determine
the details and provisions of each Stock Option Agreement, and to make all other
determinations necessary or advisable for the administration of the Plan,
including, without limitation, the amending or altering of the Plan and any
Options granted hereunder as may be required to comply with or to conform to any
federal, state or local laws or regulations.

        4.3 No Liability. Neither any Director nor any member of the Committee
shall be liable to any person for any act or determination made in good faith
with respect to the Plan or any Option granted hereunder.

        4.4 Majority Rule. A majority of the members of the Committee shall
constitute a quorum, and any action taken by a majority at a meeting at which a
quorum is present, or any action taken without a meeting evidenced by a writing
executed by all the members of the Committee, shall constitute the action of the
Committee.

        4.5 Company Assistance. The Company shall supply full and timely
information to the Committee on all matters relating to the eligibility of
Allied Orthodontists to receive a grant under the Plan, their death, disability,
or other termination of status as an Allied Orthodontist and such other
pertinent facts as the Committee may require. The Company shall furnish the
Committee with such clerical and other assistance as is necessary in the
performance of its duties.

ARTICLE V.     SHARES OF STOCK SUBJECT TO PLAN

        5.1 Limitations. Subject to any antidilution adjustment pursuant to the
provisions of Section 5.2 hereof, the maximum number of shares of Stock that may
be issued hereunder shall be Two Hundred Eighty Thousand (280,000). The amount
of Stock subject to the Plan may be increased from time to time in accordance
with Article VIII hereof. Shares of Stock subject to an Option may be either
authorized and unissued shares or shares issued and later acquired by the
Company. The shares covered by any unexercised portion of an Option that has

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terminated for any reason (except as set forth in the following paragraph) may
again be optioned under this Plan, and such shares shall not be considered as
having been optioned or issued in computing the number of shares of Stock
remaining available for Options hereunder.

        If Options are issued in respect of options to acquire stock of any
entity acquired, by merger or otherwise, by the Company or any Subsidiary, to
the extent that such issuance shall not be inconsistent with the terms,
limitations and conditions of Rule 16b-3 promulgated pursuant to the Exchange
Act, the aggregate number of shares of Stock for which Options may be granted
hereunder shall automatically be increased by the number of shares subject to
the Options so issued.

        5.2 Antidilution.

               (a) If (i) the outstanding shares of Stock are increased,
        decreased or changed into or exchanged for a different number or kind of
        shares or other securities of the Company by reason of merger,
        consolidation, reorganization, recapitalization, reclassification,
        combination or exchange of shares, or stock split or stock dividend
        (excluding the conversion of the Company's Class B Common Stock into
        shares of Stock as set forth in the Company's Amended and Restated
        Certificate of Incorporation), (ii) any spin-off, split-off or other
        distribution of assets materially affects the price of the Company's
        stock, or (iii) there is any assumption and conversion to this Plan by
        the Company of an acquired company's outstanding option grants, then:

                      (A) the aggregate number and kind of shares of Stock for
               which Options may be granted hereunder shall be adjusted
               appropriately by the Committee; and

                      (B) the rights of Optionees (concerning the number of
               shares of Stock subject to Options and the Exercise Price) under
               outstanding Options shall be adjusted appropriately by the
               Committee.

               (b) If a Change in Control occurs, the Committee, in its
        discretion, may provide notice to all Optionees that all Options granted
        under this Plan shall be assumed by the successor corporation or
        substituted on an equitable basis with options issued by such successor
        corporation.

               (c) If the Company is to be liquidated or dissolved, the adoption
        of a plan of dissolution or liquidation of the Company shall cause every
        Option outstanding under the Plan to terminate to the extent not
        exercised prior to the adoption of such plan of dissolution or
        liquidation by the stockholders, provided, however, that,
        notwithstanding any other provisions hereof, the Committee may declare
        all Options granted under the Plan to be exercisable at any time on or
        before the fifth (5th) business day following such adoption.

               (d) The adjustments described in paragraphs (a) through (c) of
        this Section 5.2, and the manner of their application, shall be
        determined solely by the Committee, and any such

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        adjustment may provide for the elimination of fractional share
        interests. The adjustments required under this Article V shall apply to
        any successors of the Company and shall be made regardless of the number
        or type of successive events requiring such adjustments.

ARTICLE VI. OPTIONS

        6.1 Types of Options Granted. The Committee may, under this Plan, grant
only non-qualified Options. Neither the Company, any Subsidiary nor any other
person warrants or otherwise represents that favorable or desirable tax
treatment or characterization will be applicable in respect of any Option or
shares of Stock relating thereto.

        6.2 Option Grant and Agreement. Each Option granted hereunder shall be
evidenced by minutes of a meeting or the written consent of the Committee and by
a written Stock Option Agreement executed by the Company and the Optionee. The
terms of the Option, including the Option's duration and exercise price, shall
be stated in the Stock Option Agreement. Every Optionee shall be given a copy of
the Plan.

        6.3 Exercise Price. The Exercise Price of the Stock subject to each
Option shall be, for the Allied Orthodontists specified in Schedule A, as
specified in Schedule A. For other Allied Orthodontists, or for other Option
grants to the Allied Orthodontists specified in Schedule A, the Exercise Price
of the Stock subject to each Option shall be determined by the Committee, but
shall not be less than the Fair Market Value of the Stock as of the date such
Option is granted.

        6.4 Exercise Period. The period for the exercise of each Option granted
hereunder shall commence immediately upon the grant date and remain exercisable
until such Option expires and is no longer exercisable after the third
anniversary of the grant date of such Option.

        6.5 Option Exercise.

               (a) Unless otherwise provided in the Stock Option Agreement or
        this Section, an Option may be exercised at any time or from time to
        time during the term of the Option as to any or all full shares subject
        to the Option, but not at any time as to less than one hundred (100)
        shares unless the remaining shares subject to the Option are less than
        one hundred (100) shares. The Committee shall have the authority to
        prescribe in any Stock Option Agreement that the Option may be exercised
        only in accordance with a vesting schedule during the term of the
        Option.

               (b) An Option shall be exercised by (i) delivery to the Company
        at its principal office of a written notice of exercise with respect to
        a specified number of shares of Stock and (ii) payment to the Company at
        that office of the full amount of the Exercise Price for such number of
        shares in accordance with Section 6.5(c).



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               (c) The Exercise Price is to be paid in full in cash by a
        certified or cashier's check payable to the Company upon the exercise of
        the Option and the Company shall not be required to deliver certificates
        for the shares purchased until such payment has been made; provided,
        however, that the Committee may provide in a Stock Option Agreement (or
        may otherwise determine in its sole discretion at the time of exercise)
        that in lieu of cash, all or any portion of the Exercise Price may be
        paid by tendering to the Company shares of Stock duly endorsed for
        transfer and owned by the Optionee, or by authorization to the Company
        to withhold shares of Stock otherwise issuable upon exercise of the
        Option, in each case to be credited against the Exercise Price at the
        Fair Market Value of such shares on the date of exercise (however, no
        fractional shares may be so transferred, and the Company shall not be
        obligated to make any cash payments in consideration of any excess of
        the aggregate Fair Market Value of shares transferred over the aggregate
        Exercise Price).

               (d) In addition to and at the time of payment of the Exercise
        Price, the Company may withhold, or require the Optionee to pay to the
        Company in cash, the amount of any federal, state and local income,
        employment or other withholding taxes which the Committee determines are
        required to be withheld under federal, state or local law in connection
        with the exercise of an Option; provided, however, the Committee may
        provide in a Stock Option Agreement (or may otherwise determine in its
        sole discretion at the time of exercise) that all or any portion of such
        tax obligations may, upon the election of the Optionee, be paid by
        tendering to the Company whole shares of Stock duly endorsed for
        transfer and owned by the Optionee, or by authorization to the Company
        to withhold shares of Stock otherwise issuable upon exercise of the
        Option, in either case in that number of shares having a Fair Market
        Value on the date of exercise equal to the amount of such taxes thereby
        being paid, and subject to such restrictions as to the approval and
        timing of any such election as the Committee may from time to time
        determine to be necessary or appropriate to satisfy the conditions of
        the exemption set forth in Rule 16b-3 under the Exchange Act, if such
        rule is applicable.

               (e) The holder of an Option shall not have any of the rights of a
        stockholder with respect to the shares of Stock subject to the Option
        until such shares have been issued and transferred to the Optionee upon
        the exercise of the Option.

        6.6 Nontransferability of Option. No Option shall be transferable by an
Optionee other than by will or the laws of descent and distribution.

ARTICLE VII. STOCK CERTIFICATES

        The Company shall not be required to issue or deliver any certificate
for shares of Stock purchased upon the exercise of any Option granted hereunder
or any portion thereof, prior to fulfillment of all of the following conditions:
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        (a) The admission of such shares to listing on the stock exchange,
Nasdaq National Market or other over-the-counter market on which the Stock is
then listed;

        (b) The completion of any registration or other qualification of such
shares which the Committee shall deem necessary or advisable under any federal
or state law or under the rulings or regulations of the Securities and Exchange
Commission or any other governmental regulatory body;

        (c) The obtaining of any approval or other clearance from any federal or
state governmental agency or body which the Committee shall determine to be
necessary or advisable; and

        (d) The lapse of such reasonable period of time following the exercise
of the Option as the Board from time to time may establish for reasons of
administrative convenience.

        Stock certificates issued and delivered to Optionees shall bear such
restrictive legends as the Company shall deem necessary or advisable pursuant to
applicable federal and state securities laws.

ARTICLE VIII. TERMINATION AND AMENDMENT OF PLAN

        8.1 Termination and Amendment. The Board may at any time terminate the
Plan, and may at any time and from time to time and in any respect amend the
Plan with or without approval of or ratification by the stockholders of the
Company.

        8.2 Effect on Optionee's Rights. No termination, amendment or
modification of the Plan shall affect adversely an Optionee's rights under a
Stock Option Agreement without the consent of the Optionee or his legal
representative, unless such termination, amendment or modification is required
to comply with applicable state and federal laws.

ARTICLE IX. RELATIONSHIP TO OTHER COMPENSATION PLANS

        The adoption of the Plan shall not affect any other stock option,
incentive, or other compensation plans in effect for the Company or any of its
Subsidiaries; nor shall the adoption of the Plan preclude the Company or any of
its Subsidiaries from establishing any other form of incentive or other
compensation plan for employees or Directors of the Company or any of its
Subsidiaries.

ARTICLE X. MISCELLANEOUS

        10.1 Replacement or Amended Grants. At the sole discretion of the
Committee, and subject to the terms of the Plan, the Committee may modify
outstanding Options or accept the surrender of outstanding Options and grant new
Options in substitution for them. However no modification of an Option shall
adversely affect an Optionee's rights under a Stock Option Agreement without the
consent of the Optionee or his legal representative, unless such modification is
required to comply with applicable state and federal laws.


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        10.2 Plan Binding on Successors. The Plan shall be binding upon the
successors and assigns of the Company.

        10.3 Headings Not Part of Plan. Headings of Articles and Sections hereof
are inserted for convenience and reference and do not constitute part of the
Plan.

        10.4 Interpretation. With respect to Section 16 Insiders, transactions
under this Plan, are intended to comply with all applicable conditions of Rule
16b-3 or its successors under the Exchange Act. To the extent any provision of
the Plan or action by the Plan administrators fails to so comply, it shall be
deemed void to the extent permitted by law and deemed advisable by the Plan
administrators.

        10.5 Governing Law. This Plan shall be governed by, and construed in
accordance with, the laws of the State of Delaware without regard to conflicts
of laws principles.


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