SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE TO/A
                                (AMENDMENT NO. 4)

        TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR SECTION 13(E)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                    INTEGRA LIFESCIENCES HOLDINGS CORPORATION
                                (Name of Issuer)

               INTEGRA LIFESCIENCES HOLDINGS CORPORATION (ISSUER)
 (Name of Filing Person (Identifying Status as Offeror, Issuer or Other Person))

            2 1/2% CONTINGENT CONVERTIBLE SUBORDINATED NOTES DUE 2008
                         (Title of Class of Securities)

                      (CUSIP NOS. 457985AA7 AND 457985AB5)
                      (CUSIP Number of Class of Securities)

                              MAUREEN B. BELLANTONI
              EXECUTIVE VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
                    INTEGRA LIFESCIENCES HOLDINGS CORPORATION
                              311 ENTERPRISE DRIVE
                          PLAINSBORO, NEW JERSEY 08536
                                 (609) 275-0500

       (Name, Address and Telephone Number of Person Authorized to Receive
          Notices and Communications on Behalf of the Filing Person(s))

                                    COPY TO:
                              PETER LABONSKI, ESQ.
                              LATHAM & WATKINS LLP
                                885 THIRD AVENUE
                               NEW YORK, NY 10022
                                 (212) 906-1200


                            CALCULATION OF FILING FEE

         TRANSACTION VALUATION*                         AMOUNT OF FILING FEE**
              $120,000,000                                     $12,840

*    Calculated  solely for the purpose of determining  the amount of the filing
     fee, based upon the exchange of $120,000,000  aggregate principal amount of
     the Issuer's 2 1/2% Contingent  Convertible  Subordinated Notes due 2008 in
     exchange for Integra LifeSciences Holdings  Corporation's 2 1/2% Contingent
     Convertible Subordinated Notes due 2008.


**   Previously paid.


[ ]  Check box if any part of the fee is offset as provided by Rule 0-11(a)(2)
     and identify the filing with which the offsetting fee was previously  paid.
     Identify the previous filing by registration  statement number, or the form
     or schedule and the date of its filing.

     Amount Previously Paid: Not applicable.       Filing party: Not applicable.
     Form or Registration No.: Not applicable.     Date Filed: Not applicable.

[ ]  Check the box if  the filing relates solely  to  preliminary communications
     made before the commencement of a tender offer.

Check the  appropriate  boxes below to designate any  transactions  to which the
statement relates:

         [ ]  third-party tender offer subject to Rule 14d-1

         [x]  issuer tender offer subject to Rule 13e-4

         [ ]  going private transaction subject to Rule 13e-3

         [ ]  amendment to Schedule 13D under Rule 13d-2


Check the following box if the filing is a final amendment reporting the results
of the tender offer [x]


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     This  Amendment  No.  4  to  Schedule  TO  (this  "Amendment")  amends  and
supplements  the  Tender  Offer  Statement  on  Schedule  TO  filed  by  Integra
LifeSciences  Holdings Corporation,  a Delaware  corporation,  (the "Issuer") on
July 17, 2006,  and amended by Amendment  No. 1 thereto  filed on July 31, 2006,
Amendment  No. 2 thereto  filed on August 15, 2006 and  Amendment  No. 3 thereto
filed on August 28, 2006 (as so amended,  the  "Schedule  TO").  This  Amendment
relates to the offer by the Issuer (i) to exchange $1,000 in principal amount of
2 1/2% Contingent Convertible  Subordinated Notes due 2008 (the "New Notes") and
(ii) a one time cash payment (an "Exchange  Fee") equal to $2.50 for each $1,000
in principal  amount of the Issuer's  outstanding 2 1/2% Contingent  Convertible
Subordinated  Notes due 2008 (the "Old Notes" and  together  with the New Notes,
the "Notes") that is properly  tendered and accepted for exchange upon the terms
and subject to the conditions set forth in the Offer to Exchange (this "Offer to
Exchange")  and  in  the  related   Letter  of   Transmittal   (the  "Letter  of
Transmittal"),  as each may be amended from time to time.  The offer to exchange
the Notes  (including  the payment of an Exchange  Fee) pursuant to the Offer to
Exchange  is  referred  to herein  as an  "Offer."  This  Amendment  amends  and
supplements  Schedule TO as set forth below.  This Amendment is filed to satisfy
the reporting  requirements  of Rule 13e-4 under the Securities  Exchange Act of
1934, as amended.

     The  information  in the  Offer  to  Exchange  and the  related  Letter  of
Transmittal,  copies of which were  previously  filed on Schedule TO as exhibits
(a)(1)(i)  and  (a)(1)(ii)   thereto,  is  incorporated  in  this  Amendment  by
reference,  except that such  information is hereby amended and  supplemented to
the extent specifically provided herein.

ITEM 11. ADDITIONAL INFORMATION

     Item 11 of the Schedule TO is hereby amended and supplemented by adding the
     following language:

     On October 2, 2006,  the  Company  issued a press  release  announcing  the
     results of the exchange offer,  which expired on September 26, 2006. A copy
     of this press release is filed as Exhibit  (a)(5)(v) to the Schedule TO and
     is incorporated herein by reference.

ITEM 12.  EXHIBITS.

     Item 12 of the Schedule TO is hereby amended and supplemented by adding the
     following exhibits:

(a)(5)(v) Press Release, dated October 2, 2006.


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SIGNATURE

     After due inquiry  and to the best of my  knowledge  and belief,  I certify
that the information set forth in this statement is true, complete and correct.

Dated:  October 3, 2006             INTEGRA LIFESCIENCES HOLDINGS
                                    CORPORATION

                                     By: /s/ MAUREEN B. BELLANTONI
                                         ---------------------------------------
                                         Name:  Maureen B. Bellantoni
                                         Title: Executive Vice President and
                                                Chief Financial Officer


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EXHIBIT INDEX

EXHIBIT
NUMBER         DESCRIPTION
------         -----------
(a)(1)(i)      Offer to Exchange, dated July 17, 2006.*

(a)(1)(ii)     Letter of Transmittal.*

(a)(1)(iii)    Notice of Guaranteed Delivery.*

(a)(1)(iv)     Letter to Brokers, Dealers, Commercial Banks, Trust Companies and
               Other Nominees.*

(a)(1)(v)      Letter to Clients for use by Brokers, Dealers, Commercial Banks,
               Trust Companies and Other Nominees.*

(a)(1)(vi)     Supplement to Offer to Exchange, dated July 31, 2006.*

(a)(1)(vii)    Supplement No. 2 to Offer to Exchange, dated August 28, 2006.*

(a)(5)(i)      Press Release, dated July 17, 2006.*

(a)(5)(ii)     Press Release, dated July 31, 2006.*

(a)(5)(iii)    Press Release, dated August 14, 2006.*

(a)(5)(iv)     Press Release, dated August 28, 2006.*

(a)(5)(v)      Press Release, dated October 2, 2006.





* Previously filed.




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