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                                                                  EXHIBIT 3.1(b)



                   CERTIFICATE OF DESIGNATION, PREFERENCES AND
                       RIGHTS OF SERIES A PREFERRED STOCK

                                       of

                         SYBRON DENTAL SPECIALTIES, INC.


         Pursuant to Section 151 of the Delaware General Corporation Law


         We, Floyd W. Pickrell, Jr., President and Chief Executive Officer, and
Stephen J. Tomassi, Vice President-General Counsel and Secretary, the
undersigned officers of Sybron Dental Specialties, Inc., a corporation organized
and existing under the Delaware General Corporation Law, in accordance with the
provisions of Section 151 thereof, DO HEREBY CERTIFY:

         That pursuant to the authority conferred upon the Board of Directors by
the Restated Certificate of Incorporation of the said Corporation, the said
Board of Directors on December 8, 2000, adopted the following resolution
creating a series of 2,500,000 shares of Preferred Stock, par value $.01 per
share, designated as Series A Preferred Stock (of which none of the shares of
such series has been issued):

         RESOLVED, that pursuant to the authority vested in the Board of
Directors of this Corporation in accordance with the provisions of its Restated
Certificate of Incorporation, a series of Preferred Stock of the Corporation be
and it hereby is created, and that the designation and amount thereof and the
voting powers, preferences and relative, participating, optional and other
special rights of the shares of such series, and the qualifications, limitations
or restrictions thereof are as follows:

         Section 1. Designation and Amount. The shares of such series shall be
designated as "Series A Preferred Stock" and the number of shares constituting
such series shall be 2,500,000.

         Section 2. Dividends and Distributions.

         (A) The holders of shares of Series A Preferred Stock shall be entitled
to receive, when, as and if declared by the Board of Directors out of funds
legally available for the purpose, quarterly dividends payable in cash on the
last business day of March, June, September and December in each year (each such
date being referred to herein as a "Quarterly Dividend Payment Date"),
commencing on the first Quarterly Dividend Payment Date after the first



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issuance of a share or fraction of a share of Series A Preferred Stock, in an
amount per share (rounded to the nearest cent) equal to the greater of (a) $1.00
or (b) subject to the provision for adjustment hereinafter set forth, 100 times
the aggregate per share amount of all cash dividends, and 100 times the
aggregate per share amount (payable in kind) of all noncash dividends or other
distributions other than a dividend payable in shares of Common Stock or a
subdivision of the outstanding shares of Common Stock (by reclassification or
otherwise), declared on the Common Stock, par value $.01 per share, of the
Corporation (the "Common Stock") since the immediately preceding Quarterly
Dividend Payment Date, or, with respect to the first Quarterly Dividend Payment
Date, since the first issuance of any share or fraction of a share of Series A
Preferred Stock. In the event the Corporation shall at any time after December
8, 2000 (the "Rights Dividend Declaration Date") (i) declare any dividend on
Common Stock payable in shares of Common Stock, (ii) subdivide the outstanding
Common Stock, or (iii) combine the outstanding Common Stock into a smaller
number of shares, then in each such case the amount to which holders of shares
of Series A Preferred Stock were entitled immediately prior to such event under
clause (b) of the preceding sentence shall be adjusted by multiplying such
amount by a fraction the numerator of which is the number of shares of Common
Stock outstanding immediately after such event and the denominator of which is
the number of shares of Common Stock that were outstanding immediately prior to
such event.

         (B) The Corporation shall declare a dividend or distribution on the
Series A Preferred Stock as provided in Paragraph (A) above immediately after it
declares a dividend or distribution on the Common Stock (other than a dividend
payable in shares of Common Stock); provided that, in the event no dividend or
distribution shall have been declared on the Common Stock during the period
between any Quarterly Dividend Payment Date and the next subsequent Quarterly
Dividend Payment Date, a dividend of $1.00 per share on the Series A Preferred
Stock shall nevertheless be payable on such subsequent Quarterly Dividend
Payment Date.

         (C) Dividends shall begin to accrue and be cumulative on outstanding
shares of Series A Preferred Stock from the Quarterly Dividend Payment Date next
preceding the date of issue of such shares of Series A Preferred Stock, unless
the date of issue of such shares is prior to the record date for the first
Quarterly Dividend Payment Date, in which case dividends on such shares shall
begin to accrue from the date of issue of such shares, or unless the date of
issue is a Quarterly Dividend Payment Date or is a date after the record date
for the determination of holders of shares of Series A Preferred Stock entitled
to receive a quarterly dividend and before such Quarterly Dividend Payment Date,
in either of which events such dividends shall begin to accrue and be cumulative
from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall
not bear interest. Dividends paid on the shares of Series A Preferred Stock in
an amount less than the total amount of such dividends at the time accrued and
payable on such shares shall be allocated pro rata on a share-by-share basis
among all such shares at the time outstanding. The Board of Directors may fix a
record date for the determination of holders of shares of Series A Preferred
Stock entitled to receive payment of a dividend or distribution declared
thereon, which record date shall be no more than 30 days prior to the date fixed
for the payment thereof.



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         Section 3. Voting Rights. The holders of shares of Series A Preferred
Stock shall have the following voting rights:

         (A) Subject to the provision for adjustment hereinafter set forth, each
share of Series A Preferred Stock shall entitle the holder thereof to 100 votes
on all matters submitted to a vote of the stockholders of the Corporation. In
the event the Corporation shall at any time after the Rights Dividend
Declaration Date (i) declare any dividend on Common Stock payable in shares of
Common Stock, (ii) subdivide the outstanding Common Stock, or (iii) combine the
outstanding Common Stock into a smaller number of shares, then in each such case
the number of votes per share to which holders of shares of Series A Preferred
Stock were entitled immediately prior to such event shall be adjusted by
multiplying such number by a fraction the numerator of which is the number of
shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

         (B) Except as otherwise provided herein or by law, the holders of
shares of Series A Preferred Stock and the holders of shares of Common Stock
shall vote together as one class on all matters submitted to a vote of
stockholders of the Corporation.

         (C)  (i) If at any time dividends on any Series A Preferred Stock shall
    be in arrears in an amount equal to six (6) quarterly dividends thereon, the
    occurrence of such contingency shall mark the beginning of a period (herein
    called a "default period") which shall extend until such time when all
    accrued and unpaid dividends for all previous quarterly dividend periods and
    for the current quarterly dividend period on all shares of Series A
    Preferred Stock then outstanding shall have been declared and paid or set
    apart for payment. During each default period, all holders of Preferred
    Stock (including holders of the Series A Preferred Stock) with dividends in
    arrears in an amount equal to six (6) quarterly dividends thereon, voting as
    a class, irrespective of series, shall have the right to elect two (2)
    directors.

              (ii) During any default period, such voting right of the holders
    of Series A Preferred Stock may be exercised initially at a special meeting
    called pursuant to subparagraph (iii) of this Section 3(C) or at any annual
    meeting of stockholders, and thereafter at annual meetings of stockholders,
    provided that neither such voting right nor the right of the holders of any
    other series of Preferred Stock, if any, to increase, in certain cases, the
    authorized number of directors shall be exercised unless the holders of ten
    percent (10%) in number of shares of Preferred Stock outstanding shall be
    present in person or by proxy. The absence of a quorum of the holders of
    Common Stock shall not affect the exercise by the holders of Preferred Stock
    of such voting right. At any meeting at which the holders of Preferred Stock
    shall exercise such voting right initially during an existing default
    period, they shall have the right, voting as a class, to elect directors to
    fill such vacancies, if any, in the Board of Directors as may then exist up
    to two (2) directors or, if such right is exercised at an annual meeting, to
    elect



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    two (2) directors. If the number which may be so elected at any special
    meeting does not amount to the required number, the holders of the Preferred
    Stock shall have the right to make such increase in the number of directors
    as shall be necessary to permit the election by them of the required number.
    After the holders of the Preferred Stock shall have exercised their right to
    elect directors in any default period and during the continuance of such
    period, the number of directors shall not be increased or decreased except
    by vote of the holders of Preferred Stock as herein provided or pursuant to
    the rights of any equity securities ranking senior to or pari passu with the
    Series A Preferred Stock.

            (iii) Unless the holders of Preferred Stock shall, during an
    existing default period, have previously exercised their right to elect
    directors, the Board of Directors may order, or any stockholder or
    stockholders owning in the aggregate not less than ten percent (10%) of the
    total number of shares of Preferred Stock outstanding, irrespective of
    series, may request, the calling of a special meeting of the holders of
    Preferred Stock, which meeting shall thereupon be called by the President, a
    Vice-President or the Secretary of the Corporation. Notice of such meeting
    and of any annual meeting at which holders of Preferred Stock are entitled
    to vote pursuant to this Paragraph (C)(iii) shall be given to each holder of
    record of Preferred Stock by mailing a copy of such notice to him at his
    last address as the same appears on the books of the Corporation. Such
    meeting shall be called for a time not earlier than 20 days and not later
    than 60 days after such order or request or in default of the calling of
    such meeting within 60 days after such order or request, such meeting may be
    called on similar notice by any stockholder or stockholders owning in the
    aggregate not less than ten percent (10%) of the total number of shares of
    Preferred Stock outstanding. Notwithstanding the provisions of this
    Paragraph (C)(iii), no such special meeting shall be called during the
    period within 60 days immediately preceding the date fixed for the next
    annual meeting of the stockholders.

            (iv) In any default period, the holders of Common Stock, and other
    classes of stock of the Corporation if applicable, shall continue to be
    entitled to elect the whole number of directors until the holders of
    Preferred Stock shall have exercised their right to elect two (2) directors
    voting as a class, after the exercise of which right (x) the directors so
    elected by the holders of Preferred Stock shall continue in office until
    their successors shall have been elected by such holders or until the
    expiration of the default period, and (y) any vacancy in the Board of
    Directors may (except as provided in Paragraph (C)(ii) of this Section 3) be
    filled by vote of a majority of the remaining directors theretofore elected
    by the holders of the class of stock which elected the director whose office
    shall have become vacant. References in this Paragraph (C) to directors
    elected by the holders of a particular class of stock shall include
    directors elected by such directors to fill vacancies as provided in clause
    (y) of the foregoing sentence.



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            (v) Immediately upon the expiration of a default period, (x) the
    right of the holders of Preferred Stock as a class to elect directors shall
    cease, (y) the term of any directors elected by the holders of Preferred
    Stock as a class shall terminate, and (z) the number of directors shall be
    such number as may be provided for in the certificate of incorporation or
    by-laws irrespective of any increase made pursuant to the provisions of
    Paragraph (C)(ii) of this Section 3 (such number being subject, however, to
    change thereafter in any manner provided by law or in the certificate of
    incorporation or by-laws). Any vacancies in the Board of Directors effected
    by the provisions of clauses (y) and (z) in the preceding sentence may be
    filled by a majority of the remaining directors.

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

         Section 4. Certain Restrictions.

         (A) Whenever quarterly dividends or other dividends or distributions
payable on the Series A Preferred Stock as provided in Section 2 are in arrears,
thereafter and until all accrued and unpaid dividends and distributions, whether
or not declared, on shares of Series A Preferred Stock outstanding shall have
been paid in full, the Corporation shall not

                         (i) declare or pay dividends on, make any other
    distributions on, or redeem or purchase or otherwise acquire for
    consideration any shares of stock ranking junior (either as to dividends or
    upon liquidation, dissolution or winding up) to the Series A Preferred
    Stock;

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

                         (iii) redeem or purchase or otherwise acquire for
    consideration shares of any stock ranking on a parity (either as to
    dividends or upon liquidation, dissolution or winding up) with the Series A
    Preferred Stock, provided that the Corporation may at any time redeem,
    purchase or otherwise acquire shares of any such parity stock in exchange
    for shares of any stock of the Corporation ranking junior (either as to
    dividends or upon dissolution, liquidation or winding up) to the Series A
    Preferred Stock; or

                         (iv) purchase or otherwise acquire for consideration
    any shares of Series A Preferred Stock, or any shares of stock ranking on a
    parity with the Series A Preferred Stock, except in accordance with a
    purchase offer made in



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    writing or by publication (as determined by the Board of Directors) to all
    holders of such shares upon such terms as the Board of Directors, after
    consideration of the respective annual dividend rates and other relative
    rights and preferences of the respective series and classes, shall determine
    in good faith will result in fair and equitable treatment among the
    respective series or classes.

         (B) The Corporation shall not permit any subsidiary of the Corporation
to purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under Paragraph (A) of this Section 4,
purchase or otherwise acquire such shares at such time and in such manner.

         Section 5. Reacquired Shares. Any shares of Series A Preferred Stock
purchased or otherwise acquired by the Corporation in any manner whatsoever
shall be retired and cancelled promptly after the acquisition thereof. All such
shares shall upon their cancellation become authorized but unissued shares of
Preferred Stock and may be reissued as part of a new series of Preferred Stock
to be created by resolution or resolutions of the Board of Directors, subject to
the conditions and restrictions on issuance set forth herein.

         Section 6. Liquidation, Dissolution or Winding Up. (A) Upon any
liquidation (voluntary or otherwise), dissolution or winding up of the
Corporation, no distribution shall be made to the holders of shares of stock
ranking junior (either as to dividends or upon liquidation, dissolution or
winding up) to the Series A Preferred Stock unless, prior thereto, the holders
of shares of Series A Preferred Stock shall have received an amount equal to
$100 per share of Series A Stock, plus an amount equal to accrued and unpaid
dividends and distributions thereon, whether or not declared, to the date of
such payment (the "Series A Liquidation Preference"). Following the payment of
the full amount of the Series A Liquidation Preference, no additional
distributions shall be made to the holders of shares of Series A Preferred Stock
unless, prior thereto, the holders of shares of Common Stock shall have received
an amount per share (the "Common Adjustment") equal to the quotient obtained by
dividing (i) the Series A Liquidation Preference by (ii) 100 (as appropriately
adjusted as set forth in subparagraph (C) below to reflect such events as stock
splits, stock dividends and recapitalizations with respect to the Common Stock)
(such number in clause (ii), the "Adjustment Number"). Following the payment of
the full amount of the Series A Liquidation Preference and the Common Adjustment
in respect of all outstanding shares of Series A Preferred Stock and Common
Stock, respectively, holders of Series A Preferred Stock and holders of shares
of Common Stock shall receive their ratable and proportionate share of the
remaining assets to be distributed in the ratio of the Adjustment Number to 1
with respect to such Preferred Stock and Common Stock, on a per share basis,
respectively.

         (B) In the event, however, that there are not sufficient assets
available to permit payment in full of the Series A Liquidation Preference and
the liquidation preferences of all other series of preferred stock, if any,
which rank on a parity with the Series A Preferred Stock, then such remaining
assets shall be distributed ratably to the holders of such parity shares in
proportion to their respective liquidation preferences. In the event, however,
that there are not




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sufficient assets available to permit payment in full of the Common Adjustment,
then such remaining assets shall be distributed ratably to the holders of Common
Stock.

         (C) In the event the Corporation shall at any time after the Rights
Dividend Declaration Date (i) declare any dividend on Common Stock payable in
shares of Common Stock, (ii) subdivide the outstanding Common Stock, or (iii)
combine the outstanding Common Stock into a smaller number of shares, then in
each such case the Adjustment Number in effect immediately prior to such event
shall be adjusted by multiplying such Adjustment Number by a fraction the
numerator of which is the number of shares of Common Stock outstanding
immediately after such event and the denominator of which is the number of
shares of Common Stock that were outstanding immediately prior to such event.

         Section 7. Consolidation, Merger, etc. In case the Corporation shall
enter into any consolidation, merger, combination or other transaction in which
the shares of Common Stock are exchanged for or changed into other stock or
securities, cash and/or any other property, then in any such case the shares of
Series A Preferred Stock shall at the same time be similarly exchanged or
changed in an amount per share (subject to the provision for adjustment
hereinafter set forth) equal to 100 times the aggregate amount of stock,
securities, cash and/or any other property (payable in kind), as the case may
be, into which or for which each share of Common Stock is changed or exchanged.
In the event the Corporation shall at any time after the Rights Dividend
Declaration Date (i) declare any dividend on Common Stock payable in shares of
Common Stock, (ii) subdivide the outstanding Common Stock, or (iii) combine the
outstanding Common Stock into a smaller number of shares, then in each such case
the amount set forth in the preceding sentence with respect to the exchange or
change of shares of Series A Preferred Stock shall be adjusted by multiplying
such amount by a fraction the numerator of which is the number of shares of
Common Stock outstanding immediately after such event and the denominator of
which is the number of shares of Common Stock that were outstanding immediately
prior to such event.

         Section 8. Ranking. The Series A Preferred Stock shall rank junior to
all other series of the Corporation's Preferred Stock as to the payment of
dividends and the distribution of assets, unless the terms of any such series
shall provide otherwise.

         Section 9. No Redemption. The shares of Series A Preferred Stock shall
not be redeemable.

         Section 10. Amendment. At any time when any shares of Series A
Preferred Stock are outstanding, neither the Restated Certificate of
Incorporation of the Corporation nor this Certificate of Designation shall be
amended in any manner which would materially alter or change the powers,
preferences or special rights of the Series A Preferred Stock so as to affect
them adversely without the affirmative vote of the holders of a majority or more
of the outstanding shares of Series A Preferred Stock, voting separately as a
class.

         Section 11. Fractional Shares. Series A Preferred Stock may be issued
in fractions of a share which shall entitle the holder, in proportion to such
holder's fractional shares,




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to exercise voting rights, receive dividends, participate in distributions and
to have the benefit of all other rights of holders of Series A Preferred Stock.

         IN WITNESS WHEREOF, we have executed and subscribed this Certificate
and do affirm the foregoing as true under the penalties of perjury this 8th day
of December, 2000.



                                     /s/ FLOYD W. PICKRELL, JR.
                                     --------------------------
                                     Floyd W. Pickrell, Jr., President and
                                     Chief Executive Officer

Attest:




/s/ STEPHEN J. TOMASSI
----------------------
Stephen J. Tomassi
Vice President-General Counsel
and Secretary