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                                                                     EXHIBIT 2.4

                           INSURANCE MATTERS AGREEMENT

         This INSURANCE MATTERS AGREEMENT (this "Agreement"), is made as of
December 11, 2000, 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, prior to the Effective Date (as defined in the Contribution
Agreement), Sybron, its subsidiaries, or its or their predecessors in interest,
as listed on Schedule 1 hereto (the "Sybron Insurance Parties" or "SIPs") and
SDS and the Dental Subsidiaries maintained various policies of insurance,
including but not limited to those listed on Schedule 2 hereto (the "Policies"),
covering, among other things, risks associated with, or arising out of, the
assets, business or operations of the Dental Business;

         WHEREAS, without relinquishing its rights as an owner of, and insured
under, the Policies, the SIPs wish to permit SDS to retain, after the Effective
Date, the same rights and benefits it enjoyed under the Policies as it had prior
to the Effective Date, and SDS wishes to assume certain of the SIPs'
responsibilities, under the Policies; and

         WHEREAS, the parties hereto intend for this Agreement to govern the
rights and obligations of the SIPs and SDS with respect to various pre-existing
contracts insuring Sybron and its subsidiaries and covering risks associated
with, or arising out of, the assets, business or operations of the Dental
Business.

         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:

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                                    ARTICLE I
                               INSURANCE COVERAGE

         1.1. Continuing Ownership. The SIPs and SDS and the Dental Subsidiaries
shall continue at all times as respective owners of, and beneficiaries under,
the Policies to the same extent each party enjoyed prior to the Effective Date,
and this Agreement shall not be construed as an attempted assignment of the
Policies or as a contract of insurance.

         1.2. List of Policies. The Policies which are listed on Schedule 1 were
obtained by the SIPs at various times prior to the date of this Agreement and
may cover risks associated with, or arising out of, the Dental Business. Neither
Sybron nor any of the other SIPs warrant that Schedule 1 contains or will
contain an accurate or complete list of the insurance potentially available to
cover the Dental Business, and state only that they have compiled the list to
the best of their abilities based on currently available information. Neither
Sybron nor any of the other SIPs shall have any obligation to undertake any
further search of their records, or the records of any third parties, to seek
additional policies or information about policies not found on Schedule 1. The
SIPs will permit SDS to review or search their records concerning policies not
available on Schedule 1, and will take reasonable steps to give SDS access to
third parties. However, each party agrees that it will share with the other any
information it gathers about additional existing policies, and that such
additional policies which are found potentially to provide coverage for risks
associated with the Dental Business shall be subject to the provisions of this
Agreement as if listed on Schedule 1 and shall be deemed within the definition
of Policies. The parties agree to generally cooperate with one another in
connection with exchanging information regarding coverage limits.

         1.3. No Warranty of Coverage. Neither Sybron nor any of the other SIPs
warrant that the Policies or any other policies of insurance provide any
coverage to SDS or the SIPs generally, or with respect to any particular risk.

         1.4. Obligation to Continue. Neither any of the SIPs nor SDS or any of
its affiliates shall cancel any Policy under which any of SDS or any of its
affiliates or any SIP, respectively, remains a beneficiary. After the Effective
Date, SDS shall be solely responsible for obtaining and maintaining all policies
of insurance covering its business and other activities after such date.

         1.5. D&O Run-Off Policy. Prior to the Effective Date, Sybron shall be
required to acquire an insurance policy covering all directors and officers of
Sybron in office as of the Effective Date for wrongful acts committed prior to
the Effective Date. Sybron shall be required to maintain such insurance policy
after the Effective Date.


                                   ARTICLE II
                           PENDING INSURED LITIGATION

         2.1. List of Pending Insured Litigation. SDS has compiled Schedule 3
which contains a list of the litigation, if any, allegedly associated with, or
arising out of, the Dental Business prior to


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the date of this Agreement for which SDS believes there may be insurance
coverage under the Policies. This litigation, together with all threatened
litigation and claims arising out of the Dental Business, shall be referred to
as "Pending Insured Litigation." SDS does not warrant that Schedule 2 contains
or will contain an accurate or complete list of the Pending Insured Litigation,
and states only that it has compiled and will compile the list to the best of
its abilities based on currently available information. Additional litigation
and threatened litigation determined by SDS at a later date as having been
omitted from Schedule 2 shall be subject to this Agreement as if listed on
Schedule 2 and shall be deemed included within the definition of Pending Insured
Litigation.

         2.2. Notice to Insurers. SDS warrants that, to the best of its
knowledge, all appropriate insurance carriers have been or will be placed on
notice concerning the Pending Insured Litigation in a timely fashion, as or if
required by the terms of the Policies.


                                  ARTICLE III
                             NEW INSURED LITIGATION

         3.1. Further Litigation or Claims. The parties acknowledge that after
the Effective Date there may be further litigation or other claims made, filed,
commenced or threatened against SDS or Sybron allegedly associated with, or
arising out of, the Dental Business ("New Insured Litigation").

         3.2. New Insured Litigation Notification. SDS shall notify Sybron of
any New Insured Litigation which may be covered under the SIP's insurance
policies.

         3.3. Notification to Sybron. SDS shall be solely responsible for
notifying all appropriate insurance carriers providing coverage to SDS or for
the activities and operations of the Dental Business, if any, regarding New
Insured Litigation and all other litigation and claims, except in cases where
the insurance carriers have refused in writing to deal directly with SDS, in
which case SDS shall promptly notify Sybron. SDS shall notify Sybron of any
litigation and claims SDS has submitted to Sybron's insurers. SDS also shall
notify Sybron promptly if it appears that New Insured Litigation may involve the
assets, business or operations of Sybron.


                                   ARTICLE IV
                          CASE HANDLING AND COOPERATION

         4.1. Cooperation with Insurers and Sybron. SDS agrees that it shall
notify, report to, and cooperate fully with the insurance carriers and Sybron
with respect to Pending Insured Litigation and New Insured Litigation as though
SDS were the named insured under the policies of insurance.

         4.2. SDS as Case Handler. The parties acknowledge that SDS has been
designated the case handler for all Pending Insured Litigation and, likewise,
may be designated by Sybron as the case handler for some or all New Insured
Litigation, under the terms of the General Assignment,


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Assumption and Agreement Regarding Litigation, Claims and Other Liabilities
between the parties of even date herewith (the "Assignment Agreement").

         4.3. Notification to Insurers. Sybron will notify the insurance
carriers issuing the Policies of the terms of this Agreement, the Contribution
Agreement, and the Assignment Agreement, and will request that the insurance
carriers deal directly with SDS, as case handler, regarding the management of
any Pending Insured Litigation and any New Insured Litigation.

         4.4. SDS to Continue as Case Handler. In the event that an insurance
carrier shall refuse or fail to deal directly with SDS, SDS shall continue as
case handler and Sybron shall provide reasonable support to SDS in communicating
with the insurance carrier.

         4.5. Actions Against Insurers. In the event SDS wishes to commence an
action against an insurance carrier for failure to provide defense or
indemnification for Pending Insured Litigation or New Insured Litigation under
one or more of the Policies, it shall not do so without informing Sybron and
obtaining Sybron's consent. Upon receipt of Sybron's consent, SDS may prosecute
such an action in the name of Sybron, in which case SDS shall bear all expenses
of the litigation and shall hold Sybron harmless from any costs of such
litigation, including without limitation fees, expenses, charges, awards of any
type or judgments which may be assessed against Sybron. Sybron's consent to the
prosecution of such an action will not be withheld or delayed unreasonably.


                                    ARTICLE V
                          PAYMENT OF COSTS AND PROCEEDS

         5.1. Payment to SDS.

                (a) To the extent that an insurance carrier pays one of the SIPs
for all or any portion of the costs of defense of, or pays all or any portion of
the amounts in settlement of, or in satisfaction of a judgment for, Pending
Insured Litigation or New Insured Litigation, for which SDS provided one of the
SIPs or itself with defense and indemnification as required by the Assignment
Agreement, such SIP shall pay over (or cause to be paid over) to SDS or for its
benefit such sums in excess of such SIP's own reasonable expenses and costs
within thirty (30) days of their receipt.

                (b) If SDS fails to defend and indemnify a SIP for a Pending
Insured Litigation matter or New Insured Litigation matter as required under the
Assignment Agreement, that SIP shall have no obligation to pay over to SDS any
portion of the payments received with respect to that matter from the insurance
carriers; provided, however, that receipt of such payments by that SIP shall not
relieve SDS of its obligations to defend or indemnify that SIP to the extent
such proceeds are insufficient to meet SDS's obligations.

         5.2. Obligation to Defend and Indemnify. It is understood between the
parties that SDS's obligation to defend, indemnify, save and hold harmless
Sybron under the Assignment Agreement shall arise at a time specified in that
Agreement which will often be prior to the time insurance


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proceeds will be available. The parties acknowledge that SDS's obligation to
provide a defense and indemnification under the Assignment Agreement shall not
be delayed pending the results of any claims made under insurance policies and
that Sybron and SDS shall account between themselves at the conclusion of a
matter if any financial adjustments are required due to the receipt of such
proceeds.

         5.3. Allocation of Deductible. To the extent a non-claim specific
deductible or self-insured retention applies, the parties agree that the
deductible or self-insured retention will be allocated proportionately among SDS
and Sybron based upon the total amount claimed by each party in any respective
insurance period.


                                   ARTICLE VI
                               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.


                                   ARTICLE VII
                                     NOTICES

         7.1. General. All notices and communications required or permitted
under this Agreement shall be in writing and any communication or delivery of
them shall be deemed to have been duly made if actually delivered, or if mailed
by first class or certified mail, postage prepaid, or by air express service,
with charges prepaid. Except for notices to insurance carriers under Section 3.2
and 3.3 and for bills and payments under Article V of this Agreement, all
notices and communications shall be addressed as follows:

                      If to any SIP:            Sybron International Corporation
                                                411 East Wisconsin Avenue
                                                Milwaukee, Wisconsin 53202
                                                Attention: General Counsel

                      If to SDS:                Sybron Dental Specialities, Inc.
                                                1717 West Collins Avenue
                                                Orange, California 92867
                                                Attention: General Counsel

         7.2. Change of Address. Either party may by written notice so delivered
to the other, change the address to which future delivery shall be made.


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                                  ARTICLE VIII
                                  MISCELLANEOUS

         8.1. 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.

         8.2. 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 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.

         8.3. 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.

         8.4. 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.

         8.5 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.

         8.6. 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


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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.

         8.7. Jurisdiction. This Agreement shall be governed and construed and
enforced in accordance with the internal laws of the State of Wisconsin (without
regard to conflict of law principles) as to all matters including, without
limitation, matters of validity, construction, effect, performance and remedies.

         8.8. 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.

         8.9. 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.

         8.10. 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 J. YONTZ
                                           -------------------------------------
                                    Name:  Kenneth J. 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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                                   SCHEDULE 1
                            SYBRON INSURANCE PARTIES


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                                   SCHEDULE 2
                               INSURANCE POLICIES


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                                   SCHEDULE 3
                           PENDING INSURED LITIGATION