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                                                                     EXHIBIT 4.6

                                PLEDGE AGREEMENT

     THIS PLEDGE AGREEMENT (the "Pledge Agreement"), dated as of December 11,
2000, is entered into by and between SYBRON DENTAL SPECIALTIES, INC., a Delaware
corporation ("SDS"), SYBRON DENTAL MANAGEMENT, INC., a Delaware corporation
("SDM"), KERR CORPORATION, a Delaware corporation ("Kerr") and LRS ACQUISITION
CORP., a Delaware corporation ("LRS")(each a "Pledgor" and collectively, the
"Pledgors") and ABN AMRO BANK N.V., as contractual representative (the
"Administrative Agent") for itself and for the "Holders of Secured Obligations"
under (and as defined in) the Credit Agreement defined below. Capitalized terms
used herein and not otherwise defined herein shall have the respective meanings
ascribed to such terms in the Credit Agreement (as defined below).

                                   WITNESSETH:

     WHEREAS, the Pledgors have entered into that certain Credit Agreement,
dated as of November 28, 2000, by and among the Pledgors, the Subsidiary Swing
Line Borrowers from time to time parties thereto, Ormco Corporation, a Delaware
Corporation, the financial institutions from time to time parties thereto as
lenders (the "Lenders"), the Administrative Agent, The Chase Manhattan Bank, as
Syndication Agent and First Union National Bank, as Documentation Agent (as
amended, restated, supplemented or otherwise modified from time to time, the
"Credit Agreement"), pursuant to which the Lenders have agreed, subject to
certain conditions precedent, to make loans and other financial accommodations
to the Borrowers from time to time;

     WHEREAS, the Pledgors, will benefit directly or indirectly from the loans
and other financial accommodations made to the Borrowers under the Credit
Agreement;

     WHEREAS, Schedule I hereto sets forth the Material Domestic Subsidiaries of
SDS (the "Initial Pledged Subsidiaries");

     WHEREAS, each Pledgor may from time to time execute and deliver to the
Administrative Agent a supplement to this Pledge Agreement substantially in the
form of Exhibit A hereto (each such supplement, a "Pledge Supplement") setting
forth additional Material Domestic Subsidiaries of SDS (the "Additional Pledged
Subsidiaries") (the Initial Pledged Subsidiaries and the Additional Pledged
Subsidiaries, collectively referred to herein as the "Pledged Subsidiaries");
and

     WHEREAS, the Administrative Agent and the Lenders have required, as a
condition to their entering into the Credit Agreement, that each Pledgor execute
and deliver this Pledge Agreement;

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     NOW, THEREFORE, for and in consideration of the foregoing and of any
financial accommodations or extensions of credit (including, without limitation,
any loan or advance by renewal, refinancing or extension of the agreements
described hereinabove or otherwise) heretofore, now or hereafter made to or for
the benefit of the Borrowers pursuant to the Credit Agreement or any other
agreement, instrument or document executed pursuant to or in connection
therewith, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, each Pledgor and the
Administrative Agent hereby agree as follows:

     Section 1. Pledge. Each Pledgor hereby pledges to the Agent, for the
benefit of the Agent and the Holders of Secured Obligations, and grants to the
Administrative Agent for the benefit of the Administrative Agent and the Holders
of Secured Obligations, a security interest in, the collateral described in
subsections (a) through (c) below (collectively, the "Pledged Collateral"):

     (a) (i) The shares of the capital stock of the Pledged Subsidiaries, now or
at any time or times hereafter owned by such Pledgor (such shares being
identified on Schedule I attached hereto or on any Schedule I attached to any
applicable Pledge Supplement), and the certificates representing the shares of
such capital stock, all options and warrants for the purchase of shares of the
stock of such Pledged Subsidiaries now or hereafter held in the name of such
Pledgor (all of said capital stock, options and warrants and all capital stock
held in the name of such Pledgor as a result of the exercise of such options or
warrants being hereinafter collectively referred to as the "Pledged Stock"),
herewith, or from time to time, delivered to the Administrative Agent
accompanied by stock powers in the form of Exhibit B attached hereto and made a
part hereof (the "Powers") duly executed in blank, and all dividends, cash,
instruments, investment property and other property from time to time received,
receivable or otherwise distributed in respect of, or in exchange for, any or
all of the Pledged Stock.

         (ii) All additional shares of capital stock of the Pledged Subsidiaries
described in Section 1(a)(i) above from time to time acquired by such Pledgor in
any manner, and the certificates, which shall be delivered to the Administrative
Agent, representing such additional shares (any such additional shares shall
constitute part of the Pledged Stock and the Administrative Agent is irrevocably
authorized to unilaterally amend Schedule I hereto or on any Schedule I to any
applicable Pledge Supplement to reflect such additional shares), and all
options, warrants, dividends, cash, instruments, investment property and other
rights and options from time to time received, receivable or otherwise
distributed in respect of or in exchange for any or all of such shares.

     (b) Other Property. The property and interests in property described in
Section 3 below.

     (c) Proceeds. All proceeds of the collateral described in subsections (a)
and (b) above.

     Section 2. Security for Obligations. The Pledged Collateral secures the
prompt payment, performance and observance of the Secured Obligations.

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     Section 3. Pledged Collateral Adjustments. If, during the term of this
Pledge Agreement:

     (a) Any stock dividend, reclassification, readjustment or other change is
declared or made in the capital structure of any of the Pledged Subsidiaries, or
any option included within the Pledged Collateral is exercised, or both, or

     (b) Any subscription warrants or any other rights or options shall be
issued in connection with the Pledged Collateral, then all new, substituted and
additional membership or partnership interests, certificates, shares, warrants,
rights, options, investment property or other securities, issued by reason of
any of the foregoing, shall be immediately delivered to and held by the
Administrative Agent under the terms of this Pledge Agreement and shall
constitute Pledged Collateral hereunder; provided, however, that nothing
contained in this Section 3 shall be deemed to permit any distribution or stock
dividend, issuance of additional membership or partnership interests or stock,
warrants, rights or options, reclassification, readjustment or other change in
the capital structure of any Pledged Subsidiary which is not expressly permitted
by the Credit Agreement.

     Section 4. Subsequent Changes Affecting Pledged Collateral. Each Pledgor
represents and warrants that it has made its own arrangements for keeping itself
informed of changes or potential changes affecting the Pledged Collateral
(including, but not limited to, rights to convert, rights to subscribe, payment
of dividends, cash distributions or other distributions reorganization or other
exchanges, tender offers and voting rights), and each Pledgor agrees that
neither the Administrative Agent nor any of the Holders of Secured Obligations
shall have any obligation to inform such Pledgor of any such changes or
potential changes or to take any action or omit to take any action with respect
thereto. The Administrative Agent may, after the occurrence of a Default,
without notice and at its option, transfer or register the Pledged Collateral or
any part thereof into its or its nominee's name with or without any indication
that such Pledged Collateral is subject to the security interest hereunder. In
addition, the Administrative Agent may after the occurrence of a Default
exchange certificates or instruments representing or evidencing Pledged Shares,
for certificates or instruments of smaller or larger denominations.

     Section 5. Representations and Warranties. Each Pledgor represents and
warrants as follows:

     (a) The Pledgor is the sole legal and beneficial owner of the percentage of
the issued and outstanding common stock of each of the Pledged Subsidiaries set
forth opposite the name of such Pledged Subsidiary on Schedule I hereto, free
and clear of any Lien except for the Liens in favor of the Administrative Agent;

     (b) The Pledgor has full corporate power and authority to enter into this
Pledge Agreement;

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     (c) There are no restrictions upon the voting rights associated with, or
upon the transfer of, any of the Pledged Collateral;

     (d) The Pledgor has the right to vote, pledge and grant a security interest
in or otherwise transfer such Pledged Collateral free of any Liens, other than
those Liens granted to the Administrative Agent and the Holders of Secured
Obligations;

     (e) The Pledgor owns the Pledged Collateral free and clear of any pledge,
mortgage, hypothecation, lien, charge, encumbrance or any security interest
therein, except for the Liens granted to the Administrative Agent and the
Holders of Secured Obligations;

     (f) The pledge of the Pledged Collateral does not violate (i) the articles
of incorporation or by-laws of the Pledged Subsidiaries, or any indenture,
mortgage, bank loan or credit agreement to which the Pledgor or any of the
Pledged Subsidiaries is a party or by which any of their respective properties
or assets may be bound; or (ii) any restriction on such transfer or encumbrance
of such Pledged Collateral;

     (g) The Pledgor agrees to execute and file financing statements pursuant to
the Uniform Commercial Code as the Administrative Agent may request to perfect
the security interest granted hereby;

     (h) No authorization, approval, or other action by, and no notice to or
filing with, any governmental authority or regulatory body that has not been
obtained is required either (i) for the pledge of the Pledged Collateral
pursuant to this Pledge Agreement or for the execution, delivery or performance
of this Pledge Agreement by the Pledgor (except for the filing of financing
statements contemplated by Section 5(g) hereof) or (ii) for the exercise by the
Administrative Agent of the voting or other rights provided for in this Pledge
Agreement or the remedies in respect of the Pledged Collateral pursuant to this
Pledge Agreement (except as may be required in connection with such disposition
by laws affecting the offering and sale of securities generally);

     (i) Upon delivery of each of the certificates representing the Pledged
Collateral, the pledge of the Pledged Collateral pursuant to this Pledge
Agreement will create a valid and perfected first priority security interest in
the Pledged Collateral, in favor of the Administrative Agent for the benefit of
the Administrative Agent and the Holders of Secured Obligations, securing the
payment and performance of the Secured Obligations;

     (j) The Powers are duly executed and give the Administrative Agent the
authority they purport to confer; and

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     (k) The Pledgor has no obligation to make further capital contributions or
make any other payments to the Pledged Subsidiaries with respect to its interest
therein.

     Section 6. Voting Rights. During the term of this Pledge Agreement, and
except as provided in this Section 6 below, each Pledgor shall have the right to
vote the Pledged Stock on all governing questions in a manner not inconsistent
with the terms of this Pledge Agreement, the Credit Agreement and any other
agreement, instrument or document executed pursuant thereto or in connection
therewith. After the occurrence and during the continuance of a Default, the
Administrative Agent or the Administrative Agent's nominee may, at the
Administrative Agent's or such nominee's option and following written notice
from the Administrative Agent to the applicable Pledgor, exercise all voting
powers pertaining to the Pledged Collateral, including the right to take action
by shareholder consent and as such exercise, or direct such Pledgor as to the
exercise of all voting, consent, managerial, election and other rights to the
applicable Pledged Collateral and exercise, or direct such Pledgor as to the
exercise of any and all rights of conversion, exchange, subscription or any
other rights, privileges or options pertaining to the applicable Pledged
Collateral, as if the Administrative Agent were the absolute owner thereof, all
without liability except to account for property actually received by it, but
the Administrative Agent shall have no duty to exercise any of the aforesaid
rights, privileges or options and shall not be responsible for any failure so to
do or delay in so doing. At all times when a Default exists, such authorization
shall constitute an irrevocable voting proxy from each Pledgor to the
Administrative Agent or, at the Administrative Agent's option, to the
Administrative Agent's nominee.

     Section 7. Dividends and Other Distributions.

     (a) So long as no Default shall have occurred and is continuing:

         (i) Each Pledgor shall be entitled to receive and retain any and all
dividends, cash distributions and interest paid in respect of the Pledged
Collateral to the extent such distributions are not prohibited by the Credit
Agreement, provided, however, that any and all

             (A) distributions, dividends and interest paid or payable other
         than in cash with respect to, and instruments and other property
         received, receivable or otherwise distributed with respect to, or in
         exchange for, any of the Pledged Collateral;

             (B) dividends and other distributions paid or payable in cash with
         respect to any of the Pledged Collateral on account of a partial or
         total liquidation or dissolution or in connection with a reduction of
         capital, capital surplus or paid-in surplus; and

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             (C) cash paid, payable or otherwise distributed with respect to
         principal of, or in redemption of, or in exchange for, any of the
         Pledged Collateral;

shall be Pledged Collateral, and shall be forthwith delivered to the
Administrative Agent to hold, for the benefit of the Administrative Agent and
the Holders of Secured Obligations, as Pledged Collateral and shall, if received
by any Pledgor, be received in trust for the Administrative Agent, for the
benefit of the Administrative Agent and the Holders of Secured Obligations, be
segregated from the other property or funds of such Pledgor, and be delivered
immediately to the Administrative Agent as Pledged Collateral in the same form
as so received (with any necessary endorsement); and

         (ii) The Administrative Agent shall execute and deliver (or cause to be
executed and delivered) to each Pledgor all such proxies and other instruments
as such Pledgor may reasonably request for the purpose of enabling such Pledgor
to receive the dividends or interest payments which it is authorized to receive
and retain pursuant to clause (i) above.

     (b) After the occurrence and during the continuance of a Default:

         (i) All rights of each Pledgor to receive the dividends, distributions
and interest payments which it would otherwise be authorized to receive and
retain pursuant to Section 7(a)(i) hereof shall cease, and all such rights shall
thereupon become vested in the Administrative Agent, for the benefit of the
Administrative Agent and the Holders of Secured Obligations, which shall
thereupon have the sole right to receive and hold as Pledged Collateral such
dividends, distributions and interest payments;

         (ii) All dividends, distributions and interest payments which are
received by any Pledgor contrary to the provisions of clause (i) of this Section
7(b) shall be received in trust for the Administrative Agent, for the benefit of
the Administrative Agent and the Holders of Secured Obligations, shall be
segregated from other funds of such Pledgor and shall be paid over immediately
to the Administrative Agent as Pledged Collateral in the same form as so
received (with any necessary endorsements);

         (iii) Each Pledgor shall, upon the request of the Administrative Agent,
at such Pledgor's expense, execute and deliver, and cause the Pledged
Subsidiaries and their respective officers and directors to execute and deliver,
all such instruments and documents, and do or cause to be done all such other
acts and things, as may be necessary or, in the opinion of the Administrative
Agent, such Pledgor or their respective counsel, advisable to register the
applicable Pledged Collateral under the provisions of the Securities Act of
1933, as amended (the "Securities Act") and to exercise its best efforts to
cause the registration statement relating thereto to become effective and to
remain effective for such period as prospectuses are required by law to be
furnished, and to make all amendments and supplements thereto and to the related
prospectus which, in the opinion of the Administrative Agent, such Pledgor or
their respective counsel, are necessary or advisable, all in conformity with the
requirements of the Securities Act and the rules and regulations of the
Securities and Exchange Commission applicable thereto;

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         (iv) Each Pledgor shall, upon the request of the Administrative Agent,
at such Pledgor's expense, use its best efforts to qualify the Pledged
Collateral under state securities or "Blue Sky" laws and to obtain all necessary
governmental approvals for the sale of the Pledged Collateral, as requested by
the Administrative Agent;

         (v) Each Pledgor shall, upon the request of the Administrative Agent,
at the such Pledgor's expense, cause the Pledged Subsidiaries to make available
to the holders of its securities, as soon as practicable, earnings statements
which will satisfy the provisions of Section 11(a) of the Securities Act; and

         (vi) Each Pledgor shall, upon the request of the Administrative Agent,
at the such Pledgor's expense, do or cause to be done all such other acts and
things as may be necessary to make such sale of the Pledged Collateral or any
part thereof valid and binding and in compliance with applicable law.

Each Pledgor will reimburse the Administrative Agent and/or the Holders of
Secured Obligations for all expenses incurred by the Administrative Agent and/or
the Holders of Secured Obligations, including, without limitation, reasonable
attorneys' and accountants' fees and expenses in connection with the foregoing.
Upon or at any time after the occurrence and during the continuance of a
Default, if the Administrative Agent determines that, prior to any public
offering of any securities constituting part of the Pledged Collateral, such
securities should be registered under the Securities Act and/or registered or
qualified under any other federal or state law and such registration and/or
qualification is not practicable, then each Pledgor agrees that it will be
commercially reasonable if a private sale, upon at least ten (10) Business Days'
notice to such Pledgor, is arranged so as to avoid a public offering, even
though the sales price established and/or obtained at such private sale may be
substantially less then prices which could have been obtained for such security
on any market or exchange or in any other public sale. Each Pledgor hereby
indemnifies and holds harmless the Administrative Agent and the Holders of
Secured Obligations for any and all liabilities incurred by either the
Administrative Agent or the Holders of Secured Obligations as a result of
becoming a shareholder of any of the Pledged Subsidiaries, except to the extent
caused by the Gross Negligence or willful misconduct of the Administrative Agent
or any Holder of Secured Obligations.

     Section 8. Transfers and Other Liens. Each Pledgor agrees that it will not
(a) sell or otherwise dispose of, or grant any option with respect to, any of
the Pledged Collateral without the prior written consent of the Administrative
Agent, except as permitted under the Credit Agreement, or (b) create or permit
to exist any Lien upon or with respect to any of the Pledged Collateral, except
for security interests in favor of the Administrative Agent.

     Section 9. Remedies.

     (a) The Administrative Agent shall have, in addition to any other rights
given under this Pledge Agreement or by law, all of the rights and remedies with
respect to the Pledged Collateral

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of a secured party under the Uniform Commercial Code as in effect in the State
of Illinois. At all time when a Default exists, the Administrative Agent
(personally or through an agent) is hereby authorized and empowered to transfer
and register in its name or in the name of its nominee the whole or any part of
the Pledged Collateral, to exercise all voting rights with respect thereto, to
collect and receive all cash dividends or distributions and other distributions
made thereon, and to otherwise act with respect to the Pledged Collateral as
though the Administrative Agent were the outright owner thereof. Each Pledgor
hereby irrevocably constitutes and appoints the Administrative Agent as the
proxy and attorney-in-fact of such Pledgor, with full power of substitution to
do so, provided, however, that the Administrative Agent shall have no duty to
exercise any such right or to preserve the same and shall not be liable for any
failure to do so or for any delay in doing so; provided, further, however that
the Administrative Agent agrees to exercise such proxy and powers only so long
as a Default shall have occurred and is continuing and following written notice
thereof. In addition, after the occurrence and during the continuance of a
Default, the Administrative Agent shall have such powers of sale and other
powers as may be conferred by applicable law. With respect to the Pledged
Collateral or any part thereof which shall then be in or shall thereafter come
into the possession or custody of the Administrative Agent or which the
Administrative Agent shall otherwise have the ability to transfer under
applicable law, the Administrative Agent may, in its sole discretion, without
notice except as specified below, after the occurrence and during the
continuance of a Default, sell or cause the same to be sold at any exchange,
broker's board or at public or private sale, in one or more sales or lots, at
such price as the Administrative Agent may deem best, for cash or on credit or
for future delivery, without assumption of any credit risk, and the purchaser of
any or all of the Pledged Collateral so sold shall thereafter own the same,
absolutely free from any claim, encumbrance or right of any kind whatsoever. The
Administrative Agent and each of the Holders of Secured Obligations may, in its
own name, or in the name of a designee or nominee, buy the Pledged Collateral at
any public sale and, if permitted by applicable law, buy the Pledged Collateral
at any private sale. Each Pledgor will pay to the Administrative Agent all
reasonable expenses (including, without limitation, court costs and reasonable
attorneys' and paralegals' fees and expenses) of, or incidental to, the
enforcement of any of the provisions hereof. The Administrative Agent agrees to
distribute any proceeds of the sale of the Pledged Collateral in accordance with
the Credit Agreement and such Pledgor shall remain liable for any deficiency
following the sale of the Pledged Collateral.

     (b) Unless any of the Pledged Collateral threatens to decline speedily in
value or is or becomes of a type sold on a recognized market, the Administrative
Agent will give each Pledgor reasonable notice of the time and place of any
public sale thereof, or of the time after which any private sale or other
intended disposition is to be made. Any sale of the Pledged Collateral conducted
in conformity with reasonable commercial practices of banks, commercial finance
companies, insurance companies or other financial institutions disposing of
property similar to the Pledged Collateral shall be deemed to be commercially
reasonable. Notwithstanding any provision to the contrary contained herein, each
Pledgor agrees that any requirements of reasonable notice shall be met if such
notice is received by such Pledgor as provided in Section 21 below at least ten
(10) Business Days before the time of the sale or disposition; provided,

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however, that Administrative Agent may give any shorter notice that is
commercially reasonable under the circumstances. Any other requirement of
notice, demand or advertisement for sale is waived, to the extent permitted by
law.

     (c) In view of the fact that federal and state securities laws may impose
certain restrictions on the method by which a sale of the Pledged Collateral may
be effected after a Default, each Pledgor agrees that after the occurrence and
during the continuance of a Default, the Administrative Agent may, from time to
time, attempt to sell all or any part of the Pledged Collateral by means of a
private placement restricting the bidders and prospective purchasers to those
who are qualified and will represent and agree that they are purchasing for
investment only and not for distribution. In so doing, the Administrative Agent
may solicit offers to buy the Pledged Collateral, or any part of it, from a
limited number of investors deemed by the Administrative Agent, in its
reasonable judgment, to be financially responsible parties who might be
interested in purchasing the Pledged Collateral. If the Administrative Agent
solicits such offers from not less than four (4) such investors, then the
acceptance by the Administrative Agent of the highest offer obtained therefrom
shall be deemed to be a commercially reasonable method of disposing of such
Pledged Collateral; provided, however, that this Section 9 does not impose a
requirement that the Administrative Agent solicit offers from four or more
investors in order for the sale to be commercially reasonable.

     Section 10. Administrative Agent Appointed Attorney-in-Fact. Each Pledgor
hereby appoints the Administrative Agent its attorney-in-fact, coupled with an
interest, with full authority, in the name of such Pledgor or otherwise, from
time to time in the Administrative Agent's sole discretion, to take any action
and to execute any instrument which the Administrative Agent may deem necessary
or advisable to accomplish the purposes of this Pledge Agreement, including,
without limitation, to receive, endorse and collect all instruments made payable
to such Pledgor representing any dividend, distribution, interest payment or
other distribution in respect of the Pledged Collateral or any part thereof and
to give full discharge for the same and to arrange for the transfer of all or
any part of the Pledged Collateral on the books of the Pledged Subsidiaries to
the name of the Administrative Agent or the Administrative Agent's nominee;
provided, however that the Administrative Agent agrees to exercise such powers
only so long as a Default shall have occurred and is continuing.

     Section 11. Waivers.

     (a) Each Pledgor waives presentment and demand for payment of any of the
Secured Obligations, protest and notice of dishonor or Default with respect to
any of the Secured Obligations and all other notices to which such Pledgor might
otherwise be entitled except as otherwise expressly provided herein or in the
Credit Agreement.

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     (b) Without limiting the generality of the foregoing or any other provision
hereof, each Pledgor hereby waives, to the fullest extent permitted by
applicable law in accordance with Section 2856 of the California Civil Code, all
rights and benefits under California Civil Code Sections 2787 to 2855,
inclusive(or any similar laws in other jurisdictions) and all rights and
benefits of California Civil Code Sections 2899 and 3433 (or any similar laws in
any other jurisdiction). In addition, without limiting the generality of the
foregoing or any other provision hereof, each Pledgor hereby waives, in
accordance with Section 2856 of the California Civil Code, all rights and
defenses (including, without limitation, all rights and defenses arising out of
an election of remedies by the Administrative Agent or any Holder of Secured
Obligations) that any Pledgor may have because the Secured Obligations are
secured by real property. This means, among other things:

         (i)  the Administrative Agent or any Holder of Secured Obligations may
              collect from any Pledgor without first foreclosing on any real or
              personal property collateral pledged to or for the benefit of the
              Administrative Agent or any Holder of Secured Obligations; and

         (ii) if the Administrative Agent or any Holder of Secured Obligations
              forecloses on any real property collateral pledged by a Borrower
              or Guarantor:

              (A) the amount of the debt may be reduced only by the price for
                  which that collateral is sold at the foreclosure sale, even if
                  the collateral is worth more than the sale price; and

              (B) the Administrative Agent or any Holder of Secured Obligations
                  may collect from any Pledgor even if the Administrative Agent
                  or any Holder of Secured Obligations, by foreclosing on the
                  real property collateral, has destroyed any right such Pledgor
                  may have to collect from a Borrower or Guarantor.

     (c) This is an unconditional and irrevocable waiver of any rights and
defenses each Pledgor may have because the Secured Obligations are secured by
real property. These rights and defenses include, but are not limited to, any
rights or defenses based upon Section 580a, 580b, 580d or 726 of the California
Code of Civil Procedure (or any similar laws in any other jurisdiction). In
accordance with Section 15 below, this Agreement shall be governed by, and shall
be construed and enforced in accordance with, the internal laws (as opposed to
the conflicts of laws provisions) and decisions of the State of Illinois. This
Section 11 and other referenced provisions of California law are included solely
out of an abundance of caution, and shall not be construed to mean that any of
the referenced provisions of California law are in any way applicable to this
Agreement or to any of the Secured Obligations.

     (d) Each Pledgor hereby expressly waives the benefits of Section 2815 of
the California Civil Code (or any similar law in any other jurisdiction)
purporting to allow a guarantor to revoke a

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continuing guaranty or pledge with respect to any transactions occurring after
the date of the guaranty or pledge. If, notwithstanding the foregoing, any
Pledgor shall have any right under applicable law to terminate or revoke its
pledge, such Pledgor agrees that such termination or revocation shall not be
effective until a written notice of such revocation or termination, specifically
referring hereto, signed by such Pledgor, is actually received by the
Administrative Agent. Such notice shall not affect the right and power of any
Holder of Secured Obligations or the Administrative Agent to enforce rights
arising prior to receipt thereof by the Administrative Agent.

     Section 12. Term. This Pledge Agreement shall remain in full force and
effect until the Secured Obligations have been fully and indefeasibly paid in
cash and the Credit Agreement has terminated pursuant to its terms. Upon the
termination of this Pledge Agreement as provided above (other than as a result
of the sale of the Pledged Collateral), the Administrative Agent will release
the security interest created hereunder and, if it then has possession of the
Pledged Stock, will deliver the Pledged Stock and the Powers to the applicable
Pledgor.

     Section 13. Definitions. The singular shall include the plural and vice
versa and any gender shall include any other gender as the context may require.

     Section 14. Successors and Assigns. This Pledge Agreement shall be binding
upon and inure to the benefit of each Pledgor, the Administrative Agent, for the
benefit of itself and the Holders of Secured Obligations, and their respective
successors and assigns. Each Pledgor's successors and assigns shall include,
without limitation, receivers, trustees or debtors-in-possession of or for such
Pledgor.

     Section 15. GOVERNING LAW. THIS PLEDGE AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS (INCLUDING, WITHOUT LIMITATION
735 ILCS SECTION 105/5-1 ET SEQ., BUT OTHERWISE WITHOUT REGARD TO THE CONFLICT
OF LAWS PROVISIONS) OF THE STATE OF ILLINOIS, BUT GIVING EFFECT TO FEDERAL LAWS
APPLICABLE TO NATIONAL BANKS. ANY DISPUTE BETWEEN THE PLEDGOR AND THE
ADMINISTRATIVE AGENT OR ANY LENDER, OR ANY OTHER HOLDER OF SECURED OBLIGATIONS
ARISING OUT OF, CONNECTED WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP
ESTABLISHED BETWEEN THEM IN CONNECTION WITH, THIS PLEDGE AGREEMENT, AND WHETHER
ARISING IN CONTRACT, TORT, EQUITY, OR OTHERWISE, SHALL BE RESOLVED IN ACCORDANCE
WITH THE INTERNAL LAWS (INCLUDING, WITHOUT LIMITATION, 735 ILCS SECTION 105/5-1
ET SEQ., BUT OTHERWISE WITHOUT REGARD TO THE CONFLICTS OF LAWS PROVISIONS) OF
THE STATE OF ILLINOIS, BUT GIVING EFFECT TO FEDERAL LAWS APPLICABLE TO NATIONAL
BANKS.

     Section 16. TRIAL. CONSENT TO JURISDICTION; SERVICE OF PROCESS; JURY

11

<PAGE>   12


     (a) EXCLUSIVE JURISDICTION. EXCEPT AS PROVIDED IN SUBSECTION (b), EACH OF
THE PARTIES HERETO AGREES THAT ALL DISPUTES AMONG THEM ARISING OUT OF, CONNECTED
WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED AMONG THEM IN
CONNECTION WITH, THIS AGREEMENT OR ANY OF THE OTHER LOAN DOCUMENTS WHETHER
ARISING IN CONTRACT, TORT, EQUITY, OR OTHERWISE, SHALL BE RESOLVED EXCLUSIVELY
BY STATE OR FEDERAL COURTS LOCATED IN CHICAGO, ILLINOIS, BUT THE PARTIES HERETO
ACKNOWLEDGE THAT ANY APPEALS FROM THOSE COURTS MAY HAVE TO BE HEARD BY A COURT
LOCATED OUTSIDE OF CHICAGO, ILLINOIS. EACH OF THE PARTIES HERETO WAIVES IN ALL
DISPUTES BROUGHT PURSUANT TO THIS SUBSECTION (a) ANY OBJECTION THAT IT MAY HAVE
TO THE LOCATION OF THE COURT CONSIDERING THE DISPUTE.

     (b) OTHER JURISDICTIONS. EACH PLEDGOR AGREES THAT THE ADMINISTRATIVE AGENT,
ANY LENDER OR ANY OTHER HOLDER OF SECURED OBLIGATIONS SHALL HAVE THE RIGHT TO
PROCEED AGAINST EACH PLEDGOR OR ITS RESPECTIVE PROPERTY IN A COURT IN ANY
LOCATION TO ENABLE SUCH PERSON TO (1) OBTAIN PERSONAL JURISDICTION OVER SUCH
PLEDGOR OR (2) REALIZE ON THE COLLATERAL GRANTED IN CONNECTION HEREWITH, OR (3)
IN ORDER TO ENFORCE A JUDGMENT OR OTHER COURT ORDER ENTERED IN FAVOR OF SUCH
PERSON. EACH PLEDGOR AGREES THAT IT WILL NOT ASSERT ANY PERMISSIVE COUNTERCLAIMS
IN ANY PROCEEDING BROUGHT BY SUCH PERSON IN A LOCATION OUTSIDE OF ILLINOIS TO
REALIZE ON ANY SECURITY FOR THE OBLIGATIONS OR TO ENFORCE A JUDGMENT OR OTHER
COURT ORDER IN FAVOR OF SUCH PERSON; PROVIDED THAT THE PLEDGORS' RIGHT TO ASSERT
PERMISSIVE COUNTERCLAIMS IN STATE OR FEDERAL COURTS LOCATED IN CHICAGO, ILLINOIS
SHALL BE PRESERVED. EACH PLEDGOR WAIVES ANY OBJECTION THAT IT MAY HAVE TO THE
LOCATION OF THE COURT IN WHICH SUCH PERSON HAS COMMENCED A PROCEEDING DESCRIBED
IN THIS SUBSECTION (b).

     (c) VENUE. THE LENDERS AND EACH PLEDGOR IRREVOCABLY WAIVES ANY OBJECTION
(INCLUDING, WITHOUT LIMITATION, ANY OBJECTION OF THE LAYING OF VENUE OR BASED ON
THE GROUNDS OF FORUM NON CONVENIENS) WHICH IT MAY NOW OR HEREAFTER HAVE TO THE
BRINGING OF ANY SUCH ACTION OR PROCEEDING WITH RESPECT TO THIS AGREEMENT OR ANY
OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION
HEREWITH IN ANY JURISDICTION SET FORTH ABOVE.

     (d) EACH PLEDGOR WAIVES PERSONAL SERVICE OF ANY PROCESS UPON IT AND
IRREVOCABLY APPOINTS CT CORPORATION, WITH OFFICES AT 208 SOUTH

12

<PAGE>   13


LASALLE STREET, CHICAGO, ILLINOIS 60604, AS THE PLEDGOR'S AGENT FOR THE PURPOSE
OF ACCEPTING SERVICE OF PROCESS ISSUED BY ANY COURT. NOTHING HEREIN SHALL IN ANY
WAY BE DEEMED TO LIMIT THE ABILITY OF THE ADMINISTRATIVE AGENT OR ANY LENDER TO
SERVE ANY SUCH WRITS, PROCESS OR SUMMONSES IN ANY OTHER MANNER PERMITTED BY
APPLICABLE LAW.

     (e) WAIVER OF JURY TRIAL. EACH OF THE PARTIES HERETO IRREVOCABLY WAIVES ANY
RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
CONTRACT, TORT, OR OTHERWISE, ARISING OUT OF, CONNECTED WITH, RELATED TO OR
INCIDENTAL TO THE RELATIONSHIP ESTABLISHED AMONG THEM IN CONNECTION WITH THIS
AGREEMENT OR ANY OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED
IN CONNECTION HEREWITH. EACH OF THE PARTIES HERETO AGREES AND CONSENTS THAT ANY
SUCH CLAIM, DEMAND, ACTION OR CAUSE OF ACTION SHALL BE DECIDED BY COURT TRIAL
WITHOUT A JURY AND THAT ANY PARTY HERETO MAY FILE AN ORIGINAL COUNTERPART OR A
COPY OF THIS AGREEMENT WITH ANY COURT AS WRITTEN EVIDENCE OF THE CONSENT OF THE
PARTIES HERETO TO THE WAIVER OF THEIR RIGHT TO TRIAL BY JURY.

     (f) WAIVER OF BOND. EACH PLEDGOR WAIVES THE POSTING OF ANY BOND OTHERWISE
REQUIRED OF ANY PARTY HERETO IN CONNECTION WITH ANY JUDICIAL PROCESS OR
PROCEEDING TO REALIZE ON THE COLLATERAL, ENFORCE ANY JUDGMENT OR OTHER COURT
ORDER ENTERED IN FAVOR OF SUCH PARTY, OR TO ENFORCE BY SPECIFIC PERFORMANCE,
TEMPORARY RESTRAINING ORDER, PRELIMINARY OR PERMANENT INJUNCTION, THIS PLEDGE
AGREEMENT OR ANY OTHER LOAN DOCUMENT.

     (g) ADVICE OF COUNSEL. EACH OF THE PARTIES REPRESENTS TO EACH OTHER PARTY
HERETO THAT IT HAS DISCUSSED THIS AGREEMENT AND, SPECIFICALLY, THE PROVISIONS OF
THIS SECTION 16, WITH ITS COUNSEL.

     Section 17. No Strict Construction. The parties hereto have participated
jointly in the negotiation and drafting of this Pledge Agreement. In the event
an ambiguity or question of intent or interpretation arises, this Pledge
Agreement shall be construed as if drafted jointly by the parties hereto and no
presumption or burden of proof shall arise favoring or disfavoring any party by
virtue of the authorship of any provisions of this Pledge Agreement.

     Section 18. Severability. Whenever possible, each provision of this Pledge
Agreement shall be interpreted in such manner as to be effective and valid under
applicable law, but, if any provision of this Pledge Agreement shall be held to
be prohibited or invalid under applicable law, such provision shall be
ineffective only to the extent of such prohibition or invalidity, without

13

<PAGE>   14


invalidating the remainder of such provision or the remaining provisions of this
Pledge Agreement.

     Section 19. Further Assurances. Each Pledgor agrees that it will cooperate
with the Administrative Agent and will execute and deliver, or cause to be
executed and delivered, all such other stock powers, proxies, instruments and
documents, and will take all such other actions, including, without limitation,
the execution and filing of financing statements, as the Administrative Agent
may reasonably request from time to time in order to carry out the provisions
and purposes of this Pledge Agreement.

     Section 20. The Administrative Agent's Duty of Care. The Administrative
Agent shall not be liable for any acts, omissions, errors of judgment or
mistakes of fact or law including, without limitation, acts, omissions, errors
or mistakes with respect to the Pledged Collateral, except for those arising out
of or in connection with the Administrative Agent's (i) Gross Negligence or
willful misconduct, or (ii) failure to use reasonable care with respect to the
safe custody of the Pledged Collateral in the Administrative Agent's possession.
Without limiting the generality of the foregoing, the Administrative Agent shall
be under no obligation to take any steps necessary to preserve rights in the
Pledged Collateral against any other parties but may do so at its option. Prior
to the occurrence of a Default, all reasonable expenses, and after and during
the continuance of a Default, all expenses incurred in connection therewith
shall be for the sole account of each Pledgor, and shall constitute part of the
Secured Obligations secured hereby.

     Section 21. Notices. All notices and other communications required or
desired to be served, given or delivered hereunder shall be given in the manner
and to the addresses set forth in the Credit Agreement.

     Section 22. Amendments, Waivers and Consents. No amendment or waiver of any
provision of this Pledge Agreement nor consent to any departure by any Pledgor
herefrom, shall in any event be effective unless the same shall be in writing
and signed by the Administrative Agent pursuant to the terms of the Credit
Agreement, and then such amendment, waiver or consent shall be effective only in
the specific instance and for the specific purpose for which given.

     Section 23. Section Headings. The section headings herein are for
convenience of reference only, and shall not affect in any way the
interpretation of any of the provisions hereof.

     Section 24. Execution in Counterparts. This Pledge Agreement may be
executed in any number of counterparts, each of which shall be an original, but
all of which shall together constitute one and the same agreement.

     Section 25. Merger. This Pledge Agreement and the other Loan Documents
embody the final and entire agreement and understanding among the Pledgors, the
Administrative Agent and the Holders of Secured Obligations and supersede all
prior agreements and understandings among the Pledgors, the Administrative Agent
and the Holders of Secured Obligations relating to the subject matter thereof.
This Pledge Agreement and the other Loan Documents may not be contradicted by
evidence of prior, contemporaneous or subsequent oral agreements of the parties.
There are no unwritten oral agreements between the parties hereto.

14

<PAGE>   15


     IN WITNESS WHEREOF, the Pledgors and the Administrative Agent have executed
this Pledge Agreement as of the date set forth above.


                                       SYBRON DENTAL SPECIALTIES, INC.


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


                                       SYBRON DENTAL MANAGEMENT, INC.


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


                                       KERR CORPORATION


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


                                       LRS ACQUISITION CORP.


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


                                       ABN AMRO BANK N.V., as Administrative
                                       Agent for itself and the Lenders


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

                       Signature Page to Pledge Agreement

<PAGE>   16


                                 ACKNOWLEDGMENT

     The undersigned hereby acknowledges receipt of a copy of the foregoing
Pledge Agreement, to the extent required by applicable law agrees promptly to
note on its books the security interests granted under such Pledge Agreement,
and waives any rights or requirement at any time hereafter to receive a copy of
such Pledge Agreement in connection with the registration of any Pledged
Collateral in the name of the Administrative Agent or its nominee or the
exercise of voting rights by the Administrative Agent or its nominee.

                                       SYBRON DENTAL MANAGEMENT, INC.


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


                                       PINNACLE PRODUCTS, INC.


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


                                       KERR CORPORATION


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


                                       ORMCO CORPORATION


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


                                       METREX RESEARCH CORPORATION


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



<PAGE>   17


                               FORM OF STOCK POWER

     FOR VALUE RECEIVED, the undersigned does hereby sell, assign and transfer
to _____________________________ _____ Shares of Common Stock of ___________, a
_____________ corporation, represented by Certificate No. __ (the "Stock"),
standing in the name of the undersigned on the books of said corporation and
does hereby irrevocably constitute and appoint _________________________________
as the undersigned's true and lawful attorney, for it and in its name and stead,
to sell, assign and transfer all or any of the Stock, and for that purpose to
make and execute all necessary acts of assignment and transfer thereof; and to
substitute one or more persons with like full power, hereby ratifying and
confirming all that said attorney or substitute or substitutes shall lawfully do
by virtue hereof.

Dated:
       ------------------


                                       [NAME OF SUBSIDIARY]


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


<PAGE>   18


                                   SCHEDULE I
                                       to
                                PLEDGE AGREEMENT
                          dated as of December 11, 2000

                              PLEDGED SUBSIDIARIES


                                  See attached



<PAGE>   19


                                    EXHIBIT A
                                       to
                                PLEDGE AGREEMENT
                          dated as of December 11, 2000

                            Form of Pledge Supplement

     Reference is hereby made to the Pledge Agreement (the "Pledge Agreement")
dated as of the 11th day of December, 2000, by and between SYBRON DENTAL
SPECIALTIES, INC., a Delaware corporation ("SDS"), SYBRON DENTAL MANAGEMENT,
INC., a Delaware corporation ("SDM"), KERR CORPORATION, a Delaware corporation
("Kerr") and LRS ACQUISITION CORP., a Delaware corporation ("LRS")(each a
"Pledgor" and collectively, the "Pledgors") and ABN AMRO BANK N.V., as
contractual representative (the "Administrative Agent") for itself and for the
"Holders of Secured Obligations" under (and as defined in) the Credit Agreement,
whereby each Pledgor has pledged certain capital stock, of the Material Domestic
Subsidiaries of SDM as collateral to the Administrative Agent, for the ratable
benefit of the Holders of Secured Obligations, as more fully described in the
Pledge Agreement. This Supplement is a "Pledge Supplement" as defined in the
Pledge Agreement and is, together with the acknowledgments, certificates and
Powers delivered herewith, subject in all respects to the terms and provisions
of the Pledge Agreement. Capitalized terms used herein and not defined herein
shall have the meanings given to them in the Pledge Agreement.

     By its execution below, each Pledgor hereby agrees that (i) the capital
stock of the corporations listed on the Schedule I hereto shall be pledged to
the Administrative Agent as additional collateral pursuant to Section 1 of the
Pledge Agreement, (ii) such property shall be considered Pledged Stock under the
Pledge Agreement and be a part of the Pledged Collateral pursuant to Section 1.1
of the Pledge Agreement, and (iii) each such corporation listed on Schedule I
hereto shall be considered a Pledged Subsidiary for purposes of the Pledge
Agreement.

     By its execution below, each Pledgor represents and warrants that it has
full corporate power and authority to execute this Pledge Supplement and that
the representations and warranties contained in Section 5 of the Pledge
Agreement are true and correct in all respects as of the date hereof and after
taking into account the pledge of the additional Pledged Stock relating hereto.

     IN WITNESS WHEREOF, each Pledgor has executed and delivered this Pledge
Supplement to the Pledge Agreement as of this __________ day of _________, ____.



                                       [                        ]
                                        ------------------------


                                       By:
                                           --------------------------
                                       Its:

<PAGE>   20


                                   SCHEDULE I
                                       TO
                                PLEDGE SUPPLEMENT

                            Additional Pledged Stock

<TABLE>
<CAPTION>
                                                              Shares of Stock                         Percentage of
                           Pledged                              owned by                              Stock owned by
                         Subsidiary        Jurisdiction of    Pledgor subject      Certificate       Pledgor subject
   Name of Pledgor          Name            Incorporation       to Pledge             Number            to Pledge
   ---------------       ----------        ---------------    ---------------      -----------       ---------------
<S>                         <C>             <C>                 <C>                   <C>               <C>

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------

   ---------------       ----------        ---------------    ---------------      -----------       ---------------
</TABLE>



<PAGE>   21


                                 ACKNOWLEDGMENT
                                       TO
                                PLEDGE SUPPLEMENT

     The undersigned hereby acknowledges receipt of a copy of the foregoing
Pledge Supplement together with a copy of the Pledge Agreement, to the extent
required by applicable law agrees promptly to note on its books the security
interests granted under such Pledge Agreement, and waives any rights or
requirement at any time hereafter to receive a copy of such Pledge Agreement in
connection with the registration of any Pledged Collateral in the name of the
Administrative Agent or its nominee or the exercise of voting rights by the
Administrative Agent or its nominee.


                                 [NAME[S] OF ADDITIONAL PLEDGED SUBSIDIARY[IES]]


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


<PAGE>   22


                                    EXHIBIT B
                                       to
                                PLEDGE AGREEMENT
                          dated as of December 11, 2000


                               Form of Stock Power

                                   STOCK POWER

     FOR VALUE RECEIVED, the undersigned does hereby sell, assign and transfer
to _____________________________ _____ Shares of Common Stock of ____________, a
__________ corporation, represented by Certificate No. __ (the "Stock"),
standing in the name of the undersigned on the books of said corporation and
does hereby irrevocably constitute and appoint _________________________________
as the undersigned's true and lawful attorney, for it and in its name and stead,
to sell, assign and transfer all or any of the Stock, and for that purpose to
make and execute all necessary acts of assignment and transfer thereof; and to
substitute one or more persons with like full power, hereby ratifying and
confirming all that said attorney or substitute or substitutes shall lawfully do
by virtue hereof.

Dated:
       ------------------


                                       [NAME OF SUBSIDIARY]


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