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                                                                     EXHIBIT 2.3


             TRADE NAME ASSIGNMENT AND TRANSITIONAL TRADE NAME USE,
                              AND LICENSE AGREEMENT

         This TRADE NAME ASSIGNMENT AND TRANSITIONAL TRADE NAME USE, AND LICENSE
AGREEMENT (this "Agreement") dated December 11, 2000, is made by and between
SYBRON INTERNATIONAL CORPORATION, a Wisconsin corporation ("Sybron"), and SYBRON
DENTAL SPECIALITIES, INC. (formerly known as "SDS Holding Co."), a Delaware
corporation ("SDS").

                                    RECITALS

         WHEREAS, pursuant to the Contribution Agreement, Plan and Agreement of
Reorganization and Distribution between the parties dated as of November 28,
2000 (the "Contribution Agreement") and pursuant to certain other agreements of
even date herewith, Sybron is transferring, or will transfer, to SDS, all of the
Dental Assets (as defined in the General Assignment, Assumption and Agreement
regarding Litigation, Claims and Other Liabilities (executed by the parties of
even date herewith);

         WHEREAS, SDS is desirous of acquiring all of Sybron's right, title and
interest to the corporate name "Sybron" (the "Trade Name"); and

         WHEREAS, the parties hereto intend hereby to provide for the license to
Sybron of the right to use the Trade Name for an interim period during which
Sybron will adopt a new corporate name.

         NOW, THEREFORE, in consideration of the premises and the mutual
promises contained in this Agreement and the other Contribution Documents (as
defined in the Contribution Agreement), the parties hereto agree as follows:

         1. Assignment. Sybron hereby sells, assigns and transfers to SDS, its
successors and assigns, and SDS hereby accepts, all of Sybron's entire right,
title and interest in and to the Trade Name, and all of Sybron's entire right,
title and interest in and to any and all claims and demands it may have, at law
or in equity, for past infringement of the Trade Name.

         2. Transitional Trade Name License and Transitional Use of Trade Name.

                  (a)      For the purpose of enabling Sybron to make a
                           transition from the Trade Name to a new corporate
                           name to be adopted by Sybron, SDS grants to Sybron,
                           for a period of one (1) year from the date of this
                           Agreement, a royalty free, nontransferable, and
                           nonexclusive license to use the Trade Name in
                           Sybron's business operations, including in connection
                           with any advertising or promotional materials,
                           subject to the quality control provision of Section 3
                           of this Agreement; provided that the license granted
                           hereunder shall be extended for an additional one (1)
                           year period in the event that Sybron is not able to
                           change its corporate name by the first anniversary of
                           this Agreement.



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                  (b)      Sybron and SDS recognize that Sybron and the
                           Laboratory Business Subsidiaries (as defined in the
                           Contribution Agreement) have acquired and produced
                           and currently possess various assets (including
                           inventory, products, packaging, and promotional
                           materials) bearing the Trade Name (the "Products").
                           Pursuant to the license granted in subsection (a)
                           above, Sybron and its subsidiaries shall have the
                           right and license to continue to acquire and produce
                           Products until the first anniversary of the date of
                           this Agreement and shall have the right and license
                           to use and sell Products until Sybron's supplies
                           thereof are exhausted.

         3. Quality Control. Sybron and the Laboratory Business Subsidiaries
shall use the Products in the same manner as they had prior to the Effective
Date. The use of the Trade Name on Products shall be in appearance and quality
reasonably satisfactory to SDS.

         4. Limitations. No license or rights under any other trademark, trade
name, trade dress, trade designation or any other property right of SDS or its
subsidiaries is granted by this Agreement. Sybron has no right to assign,
transfer or sublicense any of its rights acquired or obligations assumed under
this Agreement. Any such attempted assignment, transfer or sublicense shall be
void. Sybron and the Laboratory Business Subsidiaries shall not use or permit
the use of any trademarks or trade dress that are confusingly similar to the
Trade Name. Sybron will promptly notify SDS of any conflicting use of or acts of
infringement concerning the Trade Name and will cooperate as SDS reasonably may
deem advisable to protect SDS's rights.

         5. Dispute Resolution. In the event that any dispute or difference
arises between the parties relating to the interpretation or performance of this
Agreement, the parties shall comply with the dispute resolution procedures
prescribed in Article V of the Contribution Agreement.

         6. Miscellaneous.

                  (a)      Entire Agreement. This Agreement and the other
                           Contribution Documents constitute the entire
                           understanding of the parties hereto with respect to
                           the subject matter hereof, superseding all
                           negotiations, prior discussions and prior agreements
                           and understandings relating to their subject matter;
                           provided, however, that the specific provisions of
                           any other agreement between the parties executed and
                           delivered by the parties in connection with the
                           closing under the Contribution Agreement shall not be
                           superseded by this Agreement and to the extent any
                           such other agreement is in conflict herewith, such
                           specific agreement shall control.

                  (b)      Assignment. This Agreement and all the provisions
                           hereof shall be binding upon and inure to the benefit
                           of the parties and their respective successors and
                           permitted assigns, but neither this Agreement nor any
                           of the rights, interests or obligations hereunder
                           shall be assigned by either party without the prior
                           written

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                           consent of the other party; except that this
                           Agreement may be assigned to a parent or subsidiary
                           of a party, or to a third party acquiring
                           substantially all of the assets of a party, without
                           such prior written consent to such an assignment,
                           provided that any such third party expressly assumes,
                           and agrees to be bound by the terms of, this
                           Agreement, and provided further that the assigning
                           party shall not be relieved of any of its obligations
                           hereunder in the event of such an assignment.

                  (c)      No Third Party Beneficiaries. This Agreement is
                           solely for the benefit of the parties and is not
                           intended to confer upon any person except the parties
                           any rights or remedies hereunder. There are no third
                           party beneficiaries to this Agreement.

                  (d)      Written Amendment and Waiver. This Agreement may not
                           be altered or amended nor any rights hereunder be
                           waived, except by an instrument in writing executed
                           by the party or parties to be charged with the
                           amendment or waiver.

                  (e)      Limited Amendment or Waiver. No waiver of any term,
                           provision or condition of this Agreement or failure
                           to exercise any right, power or remedy or failure to
                           enforce any provision of this Agreement, in any one
                           or more instances, shall be deemed to be a further or
                           continuing waiver of any such term, provision or
                           condition or as a waiver of any other term, provision
                           or condition or enforcement right of this Agreement
                           or deemed to be an impairment of any right, power or
                           remedy or acquiescence to any breach.

                  (f)      Reformation and Severability. If any provision of
                           this Agreement shall be held to be invalid,
                           unenforceable or illegal in any jurisdiction under
                           any circumstances for any reason, (a) that provision
                           shall be reformed to the minimum extent necessary to
                           cause such provision to be valid, enforceable and
                           legal and preserve the original intent of the
                           parties, or (b) if that provision cannot be so
                           reformed, it shall be severed from this Agreement.
                           The holding shall not affect or impair the validity,
                           enforceability or legality of the provision in any
                           other jurisdiction or under any other circumstances.
                           Neither the holding nor the reformation or severance
                           shall affect or impair the legality, validity or
                           enforceability of any other provision of this
                           Agreement to the extent that the other provision is
                           not itself actually in conflict with any applicable
                           law. Upon a determination that any term or provision
                           is invalid, unenforceable or illegal, the parties
                           hereto shall negotiate in good faith to modify this
                           Agreement so as to effect the original intent of the
                           parties as closely as possible.

                  (g)      Jurisdiction. This Agreement shall be governed and
                           construed and enforced in accordance with the
                           internal laws of the State of Wisconsin (without
                           regard to

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                           conflict of law principles) as to all matters
                           including, without limitation, matters of validity,
                           construction, effect, performance and remedies.

                  (h)      Titles and Headings. All titles and headings have
                           been inserted solely for the convenience of the
                           parties and are not intended to be a part of this
                           Agreement or to affect its meaning or interpretation.

                  (i)      Counterparts. This Agreement, and any other agreement
                           to be executed in connection herewith, may be
                           executed in two or more counterparts, each of which
                           shall be deemed an original, but all of which
                           together shall constitute one and the same
                           instrument.

                  (j)      Effectiveness. This Agreement shall become effective
                           at the Effective Date and may be terminated by Sybron
                           at any time prior thereto without any liability on
                           either party's part.



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         IN WITNESS WHEREOF the parties have caused this Agreement to be
executed as of the date first above written by their duly authorized officers.

                                    SYBRON INTERNATIONAL CORPORATION


                                    By:  /s/ KENNETH F. YONTZ
                                       -----------------------------------------
                                    Name:  Kenneth F. Yontz
                                    Title: President and Chief Executive Officer



                                    SYBRON DENTAL SPECIALTIES, INC.



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



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