<PAGE>

                                                                    Exhibit 10.9

                                   AGREEMENT


     THIS AGREEMENT (this "Agreement") dated as of February 26, 1997 is made by
                           ---------
and between AMERICAN CYANAMID COMPANY, a Maine corporation ("ACY"), and
                                                             ---
ORAPHARMA, INC., a Delaware corporation ("OraPharma").
                                          ---------


                                 RECITALS:
                                 --------

     A.  OraPharma is engaged, among other things, in the business of developing
and commercializing pharmaceutical products for the treatment of diseases of the
oral cavity, including dental and periodontal applications.

     B.  ACY owns and has developed certain technologies relating to a
pharmaceutical product known as Minocin Periodontal, which product and
technologies may be used in the treatment of diseases of the oral cavity.  ACY's
technologies include certain drug delivery technologies that may be used in
connection with other pharmaceutical products for the treatment of diseases both
within and outside of the oral cavity.

     C.  ACY is the owner of certain patent rights having claims covering
inventions and improvements relating to Minocin Periodontal and ACY's related
drug delivery technologies.

     D.  ACY and OraPharma desire to enter into an agreement pursuant to which
(i) ACY shall transfer to OraPharma certain technologies and other assets
related to Minocin Periodontal and ACY's related drug delivery technologies and
(ii) OraPharma shall obtain from ACY, upon the terms and subject to the
conditions set forth below, (a) certain exclusive license rights to make, have
made, use, sell, have sold and otherwise commercialize Minocin Periodontal and
other products for use in the oral cavity and (b) certain non-exclusive license
rights to make, have made, use, sell, have sold and otherwise commercialize
products for use outside of the oral cavity.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
herein contained, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Parties hereby agree as
follows:

     1.  DEFINITIONS.  Whenever used in this Agreement, the following terms
shall have the following respective meanings (such meanings to be equally
applicable to both the singular and plural forms of the terms defined):

          1.1  "ACY Patent Rights" means (i) the patents listed on Schedule 1
                -----------------                                  ----------
     hereto, (ii) the patent applications listed on Schedule 1 hereto and any
                                                    ----------
     and all United States and
<PAGE>

     foreign patents based on any such patent application, (iii) any and all
     United States and foreign patents and patent applications owned or
     controlled by ACY that have one or more claims which cover any improvement
     or other enhancement to any of the inventions or subject matter claimed in
     the patents and patent applications described in clauses (i) and (ii) above
     and which is dependent upon or derivative of any such patent or patent
     application, and (iv) any and all divisions, continuations,
     continuations-in-part, renewals, reissues and extensions of any of the
     items described in clauses (i) - (iii) above.

          1.2  "ACY Product" means any product or component thereof for use
                -----------
     outside of the oral cavity and made, used or sold by ACY or any Affiliate
     or permitted sublicensee of ACY that incorporates or otherwise utilizes an
     Improvement or is otherwise subject to an Improvement License.

          1.3  "ACY Technology" means (i) any and all technology, manufacturing
                --------------
     and other know-how, technical information, inventions, discoveries,
     methods, specifications and trade secrets in the possession of ACY and/or
     its Affiliates as of the Effective Date and relating to the development,
     use and/or manufacture of MP, including, without limitation, the MP
     formulation, microencapsulation and/or polymer technology related to MP,
     the MP dispenser technology, the MP manufacturing process and the controls
     for MP, and (ii) any and all ACY improvements or other enhancements to any
     of the foregoing that are conceived or first reduced to practice by ACY at
     any time following the Effective Date and which are covered by any claim
     included within the ACY Patent Rights, but only to the extent such
     improvements or enhancements are intended for use in the oral cavity.

          1.4  "Affiliate" means, with respect to any Entity, any other Entity
                ---------
     that directly, or indirectly through one or more intermediaries, controls
     or is controlled by or is under common control with such Entity.  For
     purposes hereof, the term "control" (including, with its correlative
                                -------
     meanings, the terms "controlled by" and "under common control with") with
                          -------------       -------------------------
     respect to any Entity, means the possession, directly or indirectly, of the
     power to direct or cause the direction of the management and policies of
     such Entity (whether through the ownership of voting securities, by
     contract or otherwise); provided, that in each event in which any Entity
                             --------
     owns directly or indirectly more than 50% of the securities having ordinary
     voting power for the election of directors or other governing body of a
     corporation or more than 50% of the ownership interest of any other Entity,
     such Entity shall be deemed to control such corporation or other Entity.
     However, "Affiliates" do not include subsidiaries of an Entity in which
               ----------
     such Entity owns a majority of the ordinary voting power to elect a
     majority of the board of directors but is restricted from electing such
     majority or from otherwise having control over such subsidiary pursuant to
     a written agreement, until such time as such restrictions are no longer in
     effect.

          1.5  "Applicable Indication" means either (i) any indication in the
                ---------------------
     oral cavity or (ii) any indication outside of the oral cavity for which
     OraPharma has commenced

                                       2
<PAGE>

     research or development efforts or the manufacture, marketing and/or sale
     of one or more products.

          1.6  "Cash Reserves" means all cash and cash equivalents of OraPharma
                -------------
     as of an NDA Submission Achievement Date.

          1.7  "Confidential Information" means any and all information (in any
                ------------------------
     and every form and media) not generally known in the relevant trade or
     industry, which was obtained from either Party or any Affiliate thereof in
     connection with this Agreement or the respective rights and obligations of
     the Parties hereunder, including, without limitation, (i) information
     relating to trade secrets of such Party or any Affiliate thereof, (ii)
     information relating to existing or contemplated products, services,
     technology, designs, processes, formulae, regulatory filings relating to
     minocycline, research and development (in any and all stages) of such Party
     or any Affiliate thereof, (iii) information relating to the ACY Technology,
     the ACY Patent Rights, any Product or any Improvement, and (iv) information
     relating to business plans, methods of doing business, sales or marketing
     methods, customer lists, customer usages and/or requirements and supplier
     information of such Party or any Affiliate thereof, except that
                                                         ------
     "Confidential Information" shall not include any information which (a) at
     the time of disclosure, is generally known to the public, (b) after
     disclosure, becomes part of the public knowledge (by publication or
     otherwise) other than by breach of this Agreement by the receiving Party,
     (c) the receiving Party can verify by written documentation was in its
     possession at the time of disclosure and which was not obtained, directly
     or indirectly, from the other Party or any Affiliate thereof, (d) the
     receiving Party can verify by written documentation results from research
     and development by the receiving Party or any Affiliate thereof independent
     of disclosures by the other Party or any Affiliate thereof or (e) the
     receiving Party can prove was obtained from any Entity who had the legal
     right to disclose such information; provided, that such information was not
                                         --------
     obtained to the knowledge of the receiving Party or any Affiliate thereof
     by such Entity, directly or indirectly, from the other Party or any
     Affiliate thereof on a confidential basis.

          1.8  "Effective Date" means the date of this Agreement.
                --------------

          1.9  "Entity" means any individual, estate, trust, partnership, joint
                ------
     venture, association, limited liability company, firm, corporation or
     company, or any governmental body, agency or official, or any other entity.

          1.10  "FDA" means the United States Food and Drug Administration, and
                 ---
     any successor thereto.

          1.11  "First Commercial Sale" means the first commercial sale of a
                 ---------------------
     Product anywhere in the world.

                                       3
<PAGE>

          1.12  "Improvement" means an improvement or other enhancement to any
                 -----------
     of the inventions or subject matter claimed in any of the ACY Patent Rights
     that is (i) dependent on or derivative of such ACY Patent Right, (ii)
     patentable, and (iii) conceived or first reduced to practice by OraPharma
     or any of its Affiliates after the Effective Date.

          1.13  "Improvement License" has the meaning given to such term under
                 -------------------
     subsection 7.1.

          1.14  "Milestone Event" means either (i) an NDA Submission Milestone
                 ---------------
     or (ii) an NDA Approval Milestone.

          1.15  "MP" means the poly-glycolide-lactide micro capsules containing
                 --
     minocycline, as more particularly described on Schedule 2 hereto.
                                                    ----------

          1.16  "MP IND" means the documents filed by ACY with the FDA on May 6,
                 ------
     1988 and identified by the Number 31,597, including any amendments thereto.

          1.17  "NDA" means a New Drug Application for approval to market MP and
                 ---
     all supplements thereto filed with the FDA in accordance with 21 C.F.R.
     314.101, and that has been determined by the FDA as being sufficient to
     commence review thereof.

          1.18  "NDA Approval Achievement Date" means the date upon which an NDA
                 -----------------------------
     Approval Milestone is achieved.

          1.19  "NDA Approval Milestone" means the date upon which the FDA
                 ----------------------
     approves and authorizes OraPharma or its Affiliates to market MP for any
     indication in the oral cavity pursuant to 21 C.F.R. 314.105.

          1.20  "NDA Approval Milestone Payment" has the meaning given to such
                 ------------------------------
     term under subsection 5.4.2.

          1.21  "NDA Submission Achievement Date" means the date upon which an
                 -------------------------------
     NDA Submission Milestone is achieved.

          1.22  "NDA Submission Milestone" means the date upon which the FDA
                 ------------------------
     accepts the submission of an NDA for the marketing of MP by OraPharma or
     its Affiliates for any indication in the oral cavity in accordance with 21
     C.F.R. 314.105.

          1.23  "Net Sales" means, with respect to the sale of Products by
                 ---------
     OraPharma, its Affiliates or its sublicensees, the amount invoiced by
     OraPharma, its Affiliates and its sublicensees for the commercial sale of
     Products, less the following deductions (at the time such deductions are
     accrued or arise and to the extent not recovered or recoverable from any
     Entity): (i) trade and/or quantity discounts actually allowed and taken in

                                       4
<PAGE>

     amounts as are customary in the trade, (ii) sales and other excise taxes
     and customs duties paid, absorbed or allowed, (iii) transportation, postage
     and insurance costs that are invoiced separately or are separately stated
     in any invoice for Products, (iv) amounts repaid, credited or allowed by
     reason of rejections, defects or returns or because of retroactive price
     reductions, (v) commissions paid or allowed to brokers, distributors,
     dealers, sales representatives and agents, and (vi) invoiced amounts that
     are not paid and are written off such Entity's books as uncollectible
     (collectively, "Permitted Deductions").  In the event of any sale or other
                     --------------------
     disposition of any Product by OraPharma to any Affiliate thereof for resale
     to its customers, "Net Sales" shall be based on the greater of the amount
                        ---------
     actually received by OraPharma from its Affiliates or the amount actually
     received by such Affiliate from its customers for the sale of such
     Products, less (in either such case) the Permitted Deductions.  Any amounts
               ----
     deducted pursuant to clause (vi) above which are subsequently collected
     shall be included in Net Sales for the period in which such amounts are
     collected.

          If OraPharma or any of its Affiliates or sublicensees sells any
     Product in combination with other items which are not Products ("Other
                                                                      -----
     Items") at a single invoice price, "Net Sales" for purposes of computing
     -----                               ---------
     royalty payments on the combination shall be determined as follows:

               (i) if all Products and Other Items contained in the combination
          are available separately, "Net Sales" for purposes of computing
                                     ---------
          royalty payments shall be determined by multiplying Net Sales of the
          combination by the fraction A/A+B, where A is the selling price of all
          Products in the combination and B is the selling price of all Other
          Items in the combination;

               (ii) if the combination includes Other Items which are not sold
          separately (but all Products contained in the combination are
          available separately), "Net Sales" for purposes of computing royalty
                                  ---------
          payments shall be determined by multiplying Net Sales of the
          combination by A/C, where A is as defined in clause (i) above and C is
          the selling price of the combination; and

               (iii)  if neither the Products nor the Other Items contained in
          the combination are sold separately, the Parties agree to negotiate in
          good faith an appropriate allocation and "Net Sales" for purposes of
                                                    ---------
          computing royalty payments shall be determined by mutual agreement of
          the Parties.

          1.24  "Non-Exclusive Product" means any Non-Oral Cavity Product and
                 ---------------------
     any Oral Cavity Product for which OraPharma's license hereunder has become
     non-exclusive in accordance with the provisions of subsection 4.1 or
     subsection 4.2 hereof.

          1.25  "Non-Oral Cavity Product" means any product or component thereof
                 -----------------------
     for use outside of the oral cavity made, used or sold by OraPharma, its
     Affiliates or its

                                       5
<PAGE>

     sublicensees using any of the ACY Technology or which is covered by any
     claim included within the ACY Patent Rights.

          1.26  "Oral Cavity Product" means any product or component thereof for
                 -------------------
     use in the oral cavity made, used or sold by OraPharma, its Affiliates or
     its sublicensees using any of the ACY Technology or which is covered by any
     claim included within the ACY Patent Rights.

          1.27  "OraPharma Stock" means the voting common stock of OraPharma.
                 ---------------

          1.28  "OraPharma Stock FMV" means, with respect to the date of
                 -------------------
     determination thereof, the value of a share of OraPharma Stock, determined
     for the purposes of this Agreement as follows:

               (i) If OraPharma Stock is traded publicly on any stock exchange
          or over-the-counter market on the date a Milestone Event is achieved
          or a Royalty Credit is to be determined, then the OraPharma Stock FMV
          shall be the last ask price at which a share of OraPharma Stock may be
          purchased by an Entity on the principal stock exchange or over-the-
          counter market on which the OraPharma Stock may be purchased on such
          date.

               (ii) If OraPharma Stock is not traded publicly on any stock
          exchange or over-the-counter market on the date a Milestone Event is
          achieved or a Royalty Credit is to be determined, then the OraPharma
          Stock FMV shall be equal to the fair market value of a share of the
          last series of preferred stock issued by OraPharma and shall be
          determined as follows:

                    (a) If OraPharma consummates an equity financing during the
          period commencing on the date that is ninety (90) days prior to, and
          ending on the date that is ninety (90) days following, the achievement
          of the applicable Milestone Event or a Royalty Credit, then the
          OraPharma Stock FMV shall be the purchase price of a share of
          OraPharma preferred stock issued in the last equity financing, if any,
          consummated during such period.

                    (b) If no equity financing is consummated by OraPharma
          during the period described in clause (a) above, then the OraPharma
          Stock FMV shall be determined by OraPharma's Board of Directors and
          ACY shall be notified thereof in writing.  ACY may, upon written
          notice to OraPharma, appoint an independent certified public
          accountant or investment banking firm (an "Independent Appraiser")
                                                     ---------------------
          reasonably acceptable to OraPharma to determine the OraPharma Stock
          FMV.  If ACY fails to notify OraPharma of its election to exercise its
          valuation right within thirty (30) days after its receipt of the
          initial determination by OraPharma's Board of Directors, then the
          OraPharma Stock

                                       6
<PAGE>

          FMV shall be the amount as determined by OraPharma's Board of
          Directors. If ACY exercises its valuation right, ACY shall cause the
          Independent Appraiser appointed by ACY to provide its determination of
          the OraPharma Stock FMV in writing to OraPharma and ACY. Following
          receipt of such determination, the Parties shall, in good faith,
          attempt to mutually agree upon the OraPharma Stock FMV. If the Parties
          are unable to so agree within thirty (30) days following their receipt
          of such determination, the Parties shall appoint a mutually acceptable
          Independent Appraiser to determine the OraPharma Stock FMV. In such
          case, the determinations made by OraPharma's Board of Directors, the
          Independent Appraiser appointed by ACY and the Independent Appraiser
          jointly appointed by the Parties shall be compared, and the OraPharma
          Stock FMV shall be the middle determination (and not an average
          thereof). Any Independent Appraiser appointed by ACY or appointed
          jointly by ACY and OraPharma shall be subject to an obligation of
          confidentiality in favor of OraPharma and shall disclose to ACY only
          its determination of the OraPharma Stock FMV. The costs and expenses
          of the Independent Appraisers appointed by ACY and mutually selected
          by the parties shall be paid as follows: (I) if the OraPharma Stock
          FMV as determined by reference to the appraisals shall be less than
          eighty percent (80%) than the OraPharma Stock FMV as determined by
          OraPharma's Board of Directors, then the costs and expenses of such
          Independent Appraisers shall be shared equally by ACY and OraPharma,
          and (ii) except as provided in clause (I) of this sentence, such costs
          and expenses shall be paid solely by ACY.

          1.29  "Party" means either OraPharma and/or ACY (individually and
                 -----
     collectively).

          1.30  "Product" means any Oral Cavity Product or Non-Oral Cavity
                 -------
     Product.

          1.31  "Royalty Credits" means
                 ---------------

     [the confidential material contained herein has been omitted and has been
     separately filed with the commission.]

          1.32  "Royalty Period" means, with respect to Net Sales resulting from
                 --------------
     the commercial sale of each Product in each country, a period equal to the
     longer of (i) ten (10) years following the date of the first commercial
     sale of the applicable Product in the applicable country, or (ii) the
     period beginning on the date of the first commercial sale of the applicable
     Product in the applicable country and ending on the expiration date of the
     last to expire of any issued patent included within the ACY Patent Rights
     having a valid claim covering the manufacture, use of sale of such Product
     in such country. Royalty Periods shall be determined for each Product on a
     country-by-country basis.

          1.33  "U.S. Dollars" and the sign "$" each means the lawful currency
                 ------------                -
     of the United States of America.

                                       7
<PAGE>

     2.   LICENSES.

          2.1  Oral Cavity Products.  ACY hereby grants to OraPharma an
               --------------------
exclusive worldwide license under the ACY Patent Rights and the ACY Technology
to make, have made, use, sell, have sold and otherwise commercialize Oral Cavity
Products, which exclusive license shall be exclusive as to all other Entities
including, without limitation, ACY.  OraPharma shall have the right to grant
sublicenses to other Entities under the license granted to OraPharma pursuant to
this subsection 2.1; provided, that each sublicense granted by OraPharma shall
                     --------
be limited to one or more particular existing or proposed products or projects
of OraPharma that will be pursued in collaboration with the sublicensee.
Without limiting the foregoing, any sublicense granted by OraPharma may apply to
all of OraPharma's rights hereunder with respect to a particular existing or
proposed product or project or may be limited to one or more specific purposes
related thereto (such as, for example, development and/or manufacturing and/or
marketing).

          2.2  Non-Oral Cavity Products.  ACY hereby grants to OraPharma a non-
               ------------------------
exclusive worldwide license under the ACY Patent Rights and the ACY Technology
to make, have made, use, sell, have sold and otherwise commercialize Non-Oral
Cavity Products.  OraPharma shall have the right to grant sublicenses to other
Entities under the license granted to OraPharma pursuant to this subsection 2.2;
provided, that each sublicense granted by OraPharma shall be limited to one or
--------
more particular existing or proposed products or projects of OraPharma that will
be pursued in collaboration with the sublicensee in any field that OraPharma has
identified for the research, development, manufacture, marketing and/or sale of
products (whether or not OraPharma has then commenced any such activities in
such field).  Without limiting the foregoing, any sublicense granted by
OraPharma may apply to all of OraPharma's rights hereunder with respect to a
particular existing or proposed product or project or may be limited to one or
more specific purposes related thereto (such as, for example, development and/or
manufacturing and/or marketing).


     3.  TRANSFER OF TECHNOLOGY AND OTHER ASSETS.

         3.1  Technology Transfer.  Within forty-five (45) days following the
              -------------------
Effective Date, ACY shall disclose, convey, sell, assign and transfer to
OraPharma all ACY Technology in existence on the Effective Date.  Thereafter,
ACY shall, upon the request of OraPharma, use reasonable efforts to disclose,
convey, sell, assign and transfer to OraPharma all ACY Technology conceived or
first reduced to practice by ACY, or otherwise discovered or developed by ACY,
following the Effective Date.  Upon the reasonable request of OraPharma and for
a reasonable period of time, ACY shall cause certain of its personnel (such as
regulatory, patent, legal and research and development personnel) involved with
MP and any other ACY Technology to consult and otherwise cooperate with
OraPharma regarding the MP program and any technology related thereto.  ACY
acknowledges that such consultation and cooperation is

                                       8
<PAGE>

necessary to successfully transfer technology to OraPharma and to otherwise
enable OraPharma to perform its obligations hereunder.

          3.2  Purchase and Sale of Equipment.  ACY shall sell and transfer to
               ------------------------------
OraPharma, and OraPharma shall purchase, the equipment described on Schedule 3
                                                                    ----------
hereto (the "Equipment"), together with all drawings, manuals, operating
             ---------
instructions and operating logs related thereto, for a purchase price of $12,500
payable within thirty (30) days after the delivery date thereof.  ACY shall
deliver the Equipment and all related items to OraPharma upon such date as shall
be mutually agreed to by the Parties, but in no event sooner than thirty (30)
days following the Effective Date or later than one hundred eighty (180) days
following the Effective Date.  The Equipment shall be sold on an "AS-IS, WHERE-
IS" basis.  On the Effective Date, ACY shall execute and deliver to OraPharma a
Bill of Sale in the form of Exhibit A hereto, pursuant to which ACY shall convey
                            ---------
to OraPharma good title to the Equipment, free and clear of all liens, claims,
security interests, other encumbrances and other rights of other Entities
(except that the foregoing shall not apply to claims for patent infringement).
ACY shall also assign to OraPharma all warranties of manufacturers, if any,
respecting the Equipment by an assignment in form and content reasonably
satisfactory to OraPharma.  ACY makes no representations or warranties with
respect to the Equipment, including, but not necessarily limited to, any and all
representations or warranties with regard to merchantability and/or fitness for
a particular purpose.

          3.3  Regulatory Approvals, Reports and Records.  Within thirty (30)
               -----------------------------------------
days following the Effective Date, ACY shall transfer and deliver the following
items to OraPharma:

               (i) true and complete copies of all correspondence to the FDA or
     received from the FDA relating to MP;

               (ii) true and complete copies of any and all of the following
     reports and records relating to MP:  toxicity study reports, clinical study
     reports, case record forms, stability reports, relevant passages from
     laboratory notebooks, and product and raw material specifications;

               (iii)  the MP IND, by assignment in a form reasonably acceptable
     to OraPharma, together with a true and complete copy of the written notice
     of such transfer to OraPharma sent by ACY to the FDA;

               (iv) samples of polymer and product from ACY's retention files
     for MP as they currently exist;

               (v) true and complete copies of any and all batch records from
     clinical and toxicology batches of MP; and

                                       9
<PAGE>

               (vi) any and all data and other information (in all media and
     forms) related to the commercialization of MP or any of the ACY Technology.

During any period that ACY is providing OraPharma with minocycline pursuant to
Section 6 hereof, ACY shall provide OraPharma with cross-referencing rights to
the New Drug Application filed with the FDA for minocycline and any other
regulatory approvals, licenses or other authorizations of, or applications or
registrations filed with, any governmental authority in any country relating to
minocycline.  ACY shall maintain some of its retention samples of all clinical
samples of MP provided by ACY.  ACY shall, upon the request of OraPharma, make
available to OraPharma or any governmental authority any samples, records,
reports or other items relating to MP which are retained by ACY.

          3.4  Use of Certain Assets.  The parties agree that ACY owns
               ---------------------
trademarks, copyrights, trade dress, product shapes, packaging, label, product
and other designs and indicia of ownership associated with minocycline and the
cartons and containers therefor used for advertising and other materials
associated therewith as well as various registrations thereof, all as more fully
described in Schedule 4 hereto (hereinafter collectively, "Indicia").  OraPharma
             ----------                                    -------
hereby acknowledges the validity and ownership by ACY of any and all such
indicia and any and all registrations thereof and hereby agrees that except as
expressly provided for in this Agreement, OraPharma shall not directly or
indirectly associate, register, use, or apply or permit the association,
registration, use or application of any of such Indicia or registrations or
anything imitative of or which resembles or is confusingly similar to or with
any of such Indicia or registrations in connection with any business of or
associated with OraPharma or is sublicensees or to or with any products
manufactured, permitted, or distributed by or for OraPharma or its sublicensees.


     4.  DEVELOPMENT.

         4.1  Minocin Periodontal.  OraPharma shall use reasonable commercial
              -------------------
efforts to develop MP in accordance with the following milestone schedule:

              (i) commencement of Phase III studies not later than eighteen
     (18) months following the Effective Date;

              (ii) submission to the FDA of an NDA not later than four (4)
     years following the Effective Date; and

              (iii)  the First Commercial Sale of MP not later than six (6)
     years following the Effective Date.

The level of effort required to be expended hereunder by OraPharma to develop MP
shall be determined by OraPharma's Board of Directors in good faith after taking
into account the costs

                                       10
<PAGE>

and complexity of development, the potential profitability to OraPharma of MP,
the existence of competing products (if any) and other relevant factors. The
final dates for achievement of the milestones set forth above shall be extended
to the extent of any unreasonable delay by ACY in performing its obligations
under Section 3. If OraPharma fails to meet a milestone set forth above,
representatives of the Parties shall meet and consider the status of OraPharma's
development efforts and the circumstances underlying OraPharma's inability to
meet the applicable milestone. The Parties shall then negotiate in good faith an
extension of the applicable milestone and any remaining milestones. Any
extension shall be memorialized in an amendment to this Agreement. If the
Parties are unable to agree to an extension within six (6) months following the
final date set forth above for the achievement of the applicable milestone, and
OraPharma has not achieved the applicable milestone within such six (6) month
period, then as ACY's sole remedy therefor, the exclusive license granted to
OraPharma under subsection 2.1 shall convert automatically to a non-exclusive
license, unless ACY waives conversion under this subsection 4.1 by giving
written notice thereof to OraPharma within fifteen (15) days following the end
of such six (6) month period.

          4.2  Additional Products.  OraPharma shall use reasonable commercial
               -------------------
efforts to develop an Oral Cavity Product in addition to MP.  The level of
effort required to be expended hereunder by OraPharma to develop an additional
Oral Cavity Product shall be determined by OraPharma's Board of Directors in
good faith after taking into account the costs and complexity of development,
the stage of development, the potential profitability to OraPharma of the
particular Oral Cavity Product, the existence of competing products (if any) and
other relevant factors.  Notwithstanding the foregoing, OraPharma may satisfy
its obligations under this Section 4.2 by developing a Non-Oral Cavity Product
(which it shall have no obligation to do).  If the First Commercial Sale of an
Oral Cavity Product (other than MP) or a Non-Oral Cavity Product (which
OraPharma shall have no obligation to develop) does not occur within ten (10)
years following the Effective Date, then as ACY's sole remedy therefor, the
exclusive license granted to OraPharma under subsection 2.1 shall convert
automatically to a non-exclusive license in the case of all Oral Cavity Products
other than MP (as to which the license granted to OraPharma under subsection 2.1
shall remain exclusive), unless ACY waives conversion under this subsection 4.2
by giving written notice thereof to OraPharma  within  thirty (30) days
following the end of such ten (10) year period.

          4.3  Notification of Milestones.  Within thirty (30) days following
               --------------------------
OraPharma's achievement of any milestone described in subsections 4.1 or 4.2,
OraPharma shall notify ACY thereof in writing.


     5.  PAYMENTS.  In consideration of the transfers by ACY to OraPharma
hereunder and the grant by ACY to OraPharma of the licenses and other rights
hereunder, OraPharma shall make the following payments to ACY:

                                       11
<PAGE>

          5.1  Initial Payment.  Simultaneously with the execution and delivery
               ---------------
of this Agreement by the Parties, OraPharma shall pay to ACY Two Hundred Fifty
Thousand Dollars ($250,000) by wire transfer of immediately available funds to
an account designated by ACY.

          5.2  Equity.  ACY shall receive an equity position in OraPharma
               ------
pursuant to the terms and conditions of a Stock Purchase Agreement dated as of
the Effective Date among the Parties and certain other Entities party thereto.

          5.3  Equipment.  OraPharma shall purchase the Equipment and all items
               ---------
related thereto for a purchase price of $12,500.  The purchase price for the
Equipment shall be paid to ACY by wire transfer of immediately available funds
within thirty (30) days following the delivery of the Equipment to OraPharma.

          5.4  Milestone Payments.
               ------------------

               5.4.1  NDA Submission for Periodontal Indication.  Subject to
                      -----------------------------------------
subsection 5.4.3 hereof, ACY shall be entitled to receive a milestone payment in
the amount of Five Hundred Thousand Dollars ($500,000) upon the first
achievement of an NDA Submission Milestone for the marketing of MP for a
periodontal disease therapy; provided, that if OraPharma's Cash Reserves are
                             --------
less than Five Million Dollars ($5,000,000) on the NDA Submission Achievement
Date for such Milestone Event, OraPharma may elect, in its sole discretion, to
make such payment in either of the following forms, in lieu of the cash payment
described above:

               (i) ACY shall be entitled to receive an interest-bearing
     promissory note in the amount of Five Hundred Thousand Dollars ($500,000)
     and substantially in the form of Exhibit B hereto (the "NDA Submission
                                      ---------              --------------
     Note").  The principal amount of the NDA Submission Note shall be due and
     payable on the earlier to occur of either (a) five (5) business days
     following the consummation of a public offering by OraPharma of equity
     securities registered under the Securities Act of 1933 (as amended), if
     any, after the date of the NDA Submission Note, or (b) the date that is
     three (3) years following the date of the NDA Submission Note.  Such
     principal amount may be prepaid, in whole or in part, at any time without
     premium or penalty.  Interest shall accrue thereon at a fluctuating rate
     per annum equal to the prime rate of CitiBank, N.A. (or any successor
     thereto) in effect on the first business day of each calendar quarter, and
     shall be due and payable in arrears on the last business day of each
     calendar quarter during the term of the NDA Submission Note, with a final
     interest payment due and payable on the maturity date.  ACY shall also be
     entitled to receive warrants to purchase One Hundred Twenty Five Thousand
     Dollars ($125,000) of OraPharma Stock based upon the OraPharma Stock FMV as
     of such NDA Submission Achievement Date (the "Option 1 Warrants").  The
                                                   -----------------
     Option 1 Warrants shall be non-transferrable and may be exercised at any
     time during a period of five (5) years following the date of issuance
     thereof at a price equal to the OraPharma Stock FMV on such NDA Submission
     Achievement Date.  The number of

                                       12
<PAGE>

     shares of OraPharma Stock that ACY may purchase upon the exercise of the
     Option 1 Warrants shall be equal to the result of $125,000 divided by the
                                                                ----------
     OraPharma Stock FMV on such NDA Submission Achievement Date. For example,
     if the OraPharma Stock FMV is Five Dollars ($5.00) on such NDA Submission
     Achievement Date, ACY would receive Option 1 Warrants to purchase 25,000
     shares of OraPharma Stock at Five Dollars ($5.00) per share; or

               (ii) ACY shall be entitled to receive warrants to purchase One
     Million Dollars ($1,000,000) of OraPharma Stock based upon the OraPharma
     Stock FMV as of such NDA Submission Achievement Date (the "Option 2
                                                                --------
     Warrants").  The Option 2 Warrants shall be non-transferrable and may be
     --------
     exercised at any time during a period of five (5) years following the date
     of issuance thereof at a price equal to the OraPharma Stock FMV on such NDA
     Submission Achievement Date.  The number of shares of OraPharma Stock that
     ACY may purchase upon the exercise of the Option 2 Warrants shall be equal
     to the result of $1,000,000 divided by the OraPharma Stock FMV on such NDA
                                 ----------
     Submission Achievement Date.  For example, if the OraPharma Stock FMV is
     Five Dollars ($5.00) on such NDA Submission Achievement Date, ACY would
     receive Option 2 Warrants to purchase 200,000 shares of OraPharma Stock at
     Five Dollars ($5.00) per share.

The Parties acknowledge and agree that only one milestone payment shall be
required to be made to ACY under this subsection 5.4.1 (regardless of whether
OraPharma achieves additional NDA Submission Milestones).

          5.4.2  NDA Approval for Periodontal Indication.  Subject to subsection
                 ---------------------------------------
5.4.3 hereof, ACY shall be entitled to receive a milestone payment upon the
first achievement of an NDA Approval Milestone for the marketing of MP for a
periodontal disease therapy (the "NDA Approval Milestone Payment"), in either of
                                  ------------------------------
the following forms, as selected by OraPharma in its sole discretion:

               (i) Two Million Five Hundred Thousand Dollars ($2,500,000) by
     wire transfer of immediately available funds; or

               (ii) ACY shall be entitled to receive warrants to purchase Five
     Million Dollars ($5,000,000) of OraPharma Stock based upon the OraPharma
     Stock FMV as of the NDA Approval Achievement Date for such Milestone Event
     (the "Approval Warrants").  The Approval Warrants shall be non-
           -----------------
     transferrable and may be exercised at any time during a period of five (5)
     years following the date of issuance thereof at a price equal to the
     OraPharma Stock FMV on such NDA Approval Achievement Date.  The number of
     shares of OraPharma Stock that ACY may purchase upon the exercise of the
     Approval Warrants shall be equal to the result of $5,000,000 divided by the
                                                                  ----------
     OraPharma Stock FMV on such NDA Approval Achievement Date.  For example, if
     the OraPharma Stock FMV is Ten Dollars ($10.00) on such NDA Approval
     Achievement Date, then

                                       13
<PAGE>

     ACY would receive Approval Warrants to purchase 500,000 shares of OraPharma
     Stock at Ten Dollars ($10.00) per share.

The Parties acknowledge and agree that only one milestone payment shall be
required to be made to ACY under this subsection 5.4.2 (regardless of whether
OraPharma achieves additional NDA Approval Milestones).

          5.4.3  Milestone Events for Other Indications.  If OraPharma achieves
                 --------------------------------------
a particular Milestone Event for the marketing of MP for a non-periodontal
disease therapy indication prior to achieving the same Milestone Event for a
periodontal disease therapy indication, then ACY shall be entitled to receive a
milestone payment (a "Non-Periodontal Milestone Payment") upon the first
                      ---------------------------------
achievement thereof.  Any Non-Periodontal Milestone Payment shall be made in
accordance with the provisions of subsection 5.4.1 (in the case of an NDA
Submission Milestone) or subsection 5.4.2 (in the case of an NDA Approval
Milestone) as if the provisions thereof were applicable to a non-periodontal
disease therapy indication; provided, that the amount of any payment (including
                            --------
the principal amount of any promissory note or the U.S. Dollar amount of
OraPharma Stock, but excluding the amount of Cash Reserves) shall be fifty
percent (50%) of the applicable amount(s) set forth for periodontal disease
therapy under subsection 5.4.1 or 5.4.2, as the case may be.  If OraPharma
achieves a Milestone Event for the use of MP for a periodontal disease therapy
and, thereafter, achieves the same Milestone Event for the use of MP for any
other indication, OraPharma shall not be obligated to make additional milestone
payments under this subsection 5.4.3. If OraPharma makes any Non-Periodontal
Milestone Payment, the amount thereof shall be credited to the amount of any
milestone payment required to be made by OraPharma for the corresponding
Milestone Event for the use of MP for a periodontal disease therapy.  The
Parties acknowledge and agree that only one Non-Periodontal Milestone Payment,
if applicable, shall be made under this subsection 5.4.3 with respect to each
Milestone Event (regardless of whether OraPharma achieves additional non-
periodontal disease therapy Milestone Events).

          5.4.4  Payment.  Each milestone payment required to be made by
                 -------
OraPharma pursuant to subsections 5.4.1, 5.4.2 or 5.4.3 shall be made not later
than (i) in the case of any payment made in cash, thirty (30) days following the
achievement of the applicable Milestone Event, or (ii) in the case of any
payment made in a form other than cash, the later of ninety (90) days following
the achievement of the applicable Milestone Event or ten (10) days following the
determination of the OraPharma Stock FMV in accordance with clause (ii) of
subsection 5.4.5. Any milestone payment made in the form of cash shall be paid
by wire transfer of immediately available funds.

          5.4.5  Warrants.  Any warrants issued to ACY by OraPharma pursuant to
                 --------
this subsection 5.4 shall be in the form of Exhibit C hereto with appropriate
                                            ---------
insertions therein.

          5.5  Royalties.
               ---------

                                       14
<PAGE>

          5.5.1  Minocin Periodontal.  Subject to subsection 5.7, OraPharma
                 -------------------
shall pay to ACY a royalty on Net Sales resulting from the sale of MP during the
Royalty Period applicable to sales of MP in each country, as follows:

                    (i) Except as otherwise provided in clause (iii) below, if
          the NDA Approval Milestone Payment (for the use of MP for a
          periodontal disease therapy) is made by OraPharma pursuant to clause
          (i) of subsection 5.4.2 (i.e., $2,500,000 in cash), OraPharma shall
                                   ----
          pay to ACY a royalty in the amount of [the confidential material
          contained herein has been omitted and has been separately filed with
          the commission.]  Thereafter, OraPharma shall pay to ACY a royalty in
          the amount of [the confidential material contained herein has been
          omitted and has been separately filed with the commission.]

                    (ii) Except as otherwise provided in clause (iii) below, if
          the NDA Approval Milestone Payment (for the use of MP for a
          periodontal disease therapy) is made by OraPharma pursuant to clause
          (ii) of subsection 5.4.2 (i.e., by the issuance of the Approval
                                    ----
          Warrants) , OraPharma shall pay to ACY a royalty in the amount of [the
          confidential material contained herein has been omitted and has been
          separately filed with the commission.]

                    (iii)  If the exclusive license granted to OraPharma under
          subsection 2.1 is converted to a non-exclusive license in accordance
          with subsection 4.1 hereof, then in lieu of the royalty amounts set
          forth in clauses (i) and (ii) above, OraPharma shall pay to ACY a
          royalty in the amount of [the confidential material contained herein
          has been omitted and has been separately filed with the commission.]

             5.5.2  Other Products.  Subject to subsection 5.7, OraPharma shall
                    --------------
pay to ACY a royalty in the amount of [the confidential material contained
herein has been omitted and has been separately filed with the commission.]

          5.6  Capital Gains\Appreciation Credit.  OraPharma shall be entitled
               ---------------------------------
to a credit against any royalties payable hereunder on Net Sales resulting from
the sale of any Product by OraPharma or its Affiliates or sublicensees in an
amount equal to the aggregate Royalty Credits; provided, that the aggregate
                                               --------
amount of all credits pursuant to this subsection 5.6 shall not exceed [the
confidential material contained herein has been omitted and has been separately
filed with the commission.]  The Royalty Credits may be applied against all of
the royalties payable by OraPharma hereunder following the realization of any
capital gain or the determination of any unrealized appreciation constituting a
Royalty Credit, and until such time as the full amount of each Royalty Credit is
applied in full.

          5.7  Royalty Provisions.
               ------------------

                                       15
<PAGE>

          5.7.1  Sales to Affiliates.  Notwithstanding anything to the contrary
                 -------------------
contained herein, no royalties shall be payable by OraPharma hereunder with
respect to sales of any Product to any of its Affiliates or by any of
OraPharma's Affiliates to any other Affiliate thereof.  ACY shall be entitled to
royalties on any Product sold by OraPharma or its Affiliates to third parties as
provided in Section 5.5.

          5.7.2  No Patents.  The royalties payable under subsection 5.5 on
                 ----------
sales of any Product to a third party located in a country or countries in which
ACY has not obtained an issued patent then having one or more valid current
claims covering such Product shall be reduced, on a country-by-country basis, to
(i) [the confidential material contained herein has been omitted and has been
separately filed with the commission.] and (ii) [the confidential material
contained herein has been omitted and has been separately filed with the
commission.] provided that the reduction shall apply only during the period in
             --------
which such patent is not issued or does not have one or more valid current
claims covering such Product.

          5.7.3  No Multiple Royalties.  If a Product, or the manufacture, use
                 ---------------------
or sale thereof, is covered by more than one ACY Patent Right or by more than
one license granted hereunder, OraPharma shall be responsible for payment of
only one royalty based on the Net Sales thereof, such royalty to be equal to the
highest applicable royalty rate on a Product-by-Product and country-by-country
basis.  If OraPharma has paid a royalty to ACY with respect to any component of
a Product that is incorporated into a finished Product that is manufactured and
sold by a sublicensee, OraPharma shall be entitled to a credit against any
royalty payable to ACY on Net Sales of the finished Product by OraPharma's
sublicensee in the amount of the total royalty paid by OraPharma with respect to
such component.

          5.7.4  Third Party Patents.  If OraPharma shall be required by a third
                 -------------------
party or an Affiliate in an arms-length transaction to obtain a license under
any patent or other rights or to make other arrangements in order for OraPharma
to make, have made, use, sell, have sold or otherwise commercialize any Product
in any geographical area in which such Entity has an issued patent then existing
having one or more valid current claims covering the manufacture, use or sale of
such Product, then OraPharma shall be entitled to a credit against the royalty
payments due hereunder in an amount equal to the royalty payments or other
amounts payable to such other Entity, provided, that such offset shall not
                                      --------
exceed [the confidential treatment contained herein has been omitted and has
been separately filed with the commission.]  It is the intention of the parties
that the credit defined in this Section 5.7.4 shall apply to royalty payments
payable to the Debiopharm Companies pursuant to an agreement dated February 13,
1997 (a copy of which is attached as Exhibit E hereto) and to Gary R. Jernberg,
D.D.S., M.S.D. pursuant to an agreement dated December 19, 1996   (a copy of
which is attached as Exhibit F hereto).

          5.7.5  Most Favored Licensee.  Except for the Agreement referred to in
                 ---------------------
Section 10.2 (iv) hereof, it is the intention of the Parties that OraPharma
receive most favored licensee status and treatment under this Agreement with
respect to Non-Exclusive Products.

                                       16
<PAGE>

Accordingly, if any non-exclusive license granted by ACY to another Entity
(other than an Affiliate of ACY) under the ACY Patent Rights or the ACY
Technology to make, use or sell any product that is ultimately sold to consumers
by prescription, on the one hand, or over-the- counter, on the other, provides
for payments and/or rates of royalties applicable to the sale of any such
product(s) in any country or countries which (calculated on an equivalent basis
with respect to the ACY Patent Rights) are lower than those provided in this
Agreement, ACY shall (i) promptly notify OraPharma in writing of such license,
and (ii) extend to OraPharma such lower payments and/or rates of royalty with
respect to Net Sales by OraPharma and its Affiliates and sublicensees of
Non-Exclusive Products that are ultimately sold to consumers by prescription or
over-the-counter, as the case may be, in the same country or countries effective
as of the date or dates on which such payments and/or rates of royalty shall
become effective with respect to such products pursuant to such license.

          5.8  Payment of Royalties.  Royalties payable by OraPharma hereunder
               --------------------
shall be paid within sixty (60) days after the end of each calendar quarter
based on the Net Sales resulting from sales of Products by OraPharma, its
Affiliates and sublicensees during the preceding calendar quarter.  Such
payments shall be accompanied by a statement setting forth the Net Sales of
Products by OraPharma, its Affiliates and sublicensees.

          5.9  Accounting; Foreign Currency.  The aggregate amount of the Net
               ----------------------------
Sales used for computing the royalties payable by OraPharma hereunder shall be
computed in U.S. Dollars, and all payments of such royalties shall be made in
U.S. Dollars.  For purposes of determining the amount of royalties due, the
amount of Net Sales in any foreign currency (the "Other Currency") shall be
                                                  --------------
computed generally by converting such amount into U.S. Dollars at the prevailing
commercial rate of exchange for purchasing U.S. Dollars as quoted in The Wall
Street Journal (International Edition) on the last business day of the calendar
quarter with respect to which such royalty payment is payable by OraPharma.  In
the event that any Other Currency shall, at the time that a royalty payment in
respect of Net Sales in such Other Currency is due, not be convertible into
Dollars and freely transferable by reason of any governmental regulation or any
moratorium, embargo, banking restriction or other restriction, the obligation of
OraPharma to make payment of such royalties shall, upon notice thereof given by
OraPharma to ACY, be suspended until such time as such Other Currency shall be
convertible into Dollars and freely transferable to the United States; provided,
                                                                       --------
further, that, in such event, ACY may, by written notice to OraPharma, request
-------
that such royalties be paid by OraPharma in such Other Currency (calculated on
the basis of Net Sales in such Other Currency) and deposited in a local bank
account in the relevant country specified by ACY, in the name of ACY.  During
any period of non-payment of royalties hereunder, the amount of Net Sales on
which royalties are due and payable by OraPharma shall accrue in the Other
Currency in which they were paid. OraPharma shall pay to ACY the amount of
accrued royalties in respect of any such Net Sales, plus any interest actually
accrued thereon, within a reasonable period of time after the date on which the
relevant Other Currency shall become convertible into U.S. Dollars and freely
transferable to the United States.

                                       17
<PAGE>

          5.10  Withholding Taxes.  The Parties acknowledge and agree that there
                -----------------
may be deducted from any payments or royalties otherwise due and payable
hereunder any taxes or other payments required to be withheld under applicable
law with respect to such payments or royalties or otherwise relating to
Products.  OraPharma shall promptly submit to ACY any official receipt received
by OraPharma for such tax or other payments.

          5.11  Records.  OraPharma shall keep for three (3) years complete and
                -------
accurate records of Net Sales from sales of Products by OraPharma and its
Affiliates in sufficient detail to allow the royalties payable by OraPharma
hereunder to be accurately determined.  Each sublicense agreement entered into
by OraPharma shall expressly require OraPharma's sublicensee also to maintain
such records.  ACY shall have the right for a period of three (3) years after
receiving any report or statement with respect to royalties due and payable
hereunder to appoint an independent accounting firm reasonably acceptable to
OraPharma to inspect and audit the relevant records of OraPharma, its Affiliates
or sublicensees to verify such report or statement.  OraPharma, its Affiliates
and their sublicensees shall make their records available for inspection and
audit by such independent accounting firm during regular business hours at such
place or places where such records are customarily kept, upon reasonable notice
to OraPharma, its Affiliate or its sublicensee to the extent reasonably
necessary to verify the accuracy of the reports and payments required hereunder;

provided, that such inspection and audit right shall not be exercised more than
--------
once in any calendar year.  ACY shall be responsible for the cost of any such
inspection and audit by an independent accounting firm, unless such inspection
and audit discloses for any calendar quarter examined that there shall have been
a discrepancy in favor of OraPharma of greater than 10% between the royalties
payable by OraPharma hereunder and the royalties actually paid to ACY with
respect to such calendar quarter, in which case OraPharma shall be responsible
for the payment of the reasonable cost of such inspection and audit.


     60  SUPPLY OF MINOCYCLINE.  OraPharma shall have the right, but not the
obligation, to purchase from ACY minocycline in micronized bulk form or milled
bulk form, at OraPharma's option, so long as ACY continues to manufacture
minocycline; provided, that nothing contained herein shall obligate ACY to
             --------
continue the manufacture of minocycline.  ACY shall provide OraPharma with at
least twelve (12) months prior written notice if ACY intends to cease the
manufacture of minocycline.  The purchase price for any minocycline sold to
OraPharma by ACY shall be the lowest amount that ACY charges any Entity, other
than an Affiliate, for minocycline in the form purchased by OraPharma, and shall
be payable upon such terms as shall be agreed to by the Parties in a separate
Supply Agreement.  Upon request, ACY agrees to manufacture and sell to OraPharma
such quantities of minocycline as OraPharma may from time to time require and in
such form as OraPharma shall request.  ACY shall use reasonable commercial
efforts to deliver to OraPharma all minocycline reasonably requested by
OraPharma in the form, in the quantity, at the time or times and at the
destination specified by OraPharma.  If any shipment of minocycline may be
delayed for any reason, ACY agrees to promptly notify OraPharma of the delay and
the expected duration.  ACY shall perform a final quality control test on
minocycline before shipment to OraPharma and shall furnish to

                                       18
<PAGE>

OraPharma a certificate of analysis with each shipment of minocycline.
OraPharma's right to purchase minocycline pursuant to this Section 6 shall
extend to all Affiliates and sublicensees of OraPharma, but only for the use of
minocycline in the manufacture of MP.

     70   IMPROVEMENTS.

          7.1  Option.  OraPharma hereby grants to ACY a non-exclusive option to
               ------
acquire a worldwide non-exclusive royalty bearing license with respect to each
Improvement solely for use in fields outside of the oral cavity (an "Improvement
                                                                     -----------
License"), exercisable as provided below in subsection 7.2. OraPharma shall
-------
promptly notify ACY of each Improvement after OraPharma has filed or caused to
be filed a patent application with respect thereto.  Each notice of an
Improvement shall describe the Improvement in reasonable detail.  ACY shall have
a period of ninety (90) days after receipt of each such notice (the "Option
                                                                     ------
Period") to evaluate the applicable Improvement and to exercise its option.
------

          7.2  Exercise of Option.  If ACY desires to exercise its option to
               ------------------
obtain an Improvement License with respect to any Improvement, ACY shall notify
OraPharma thereof in writing not later than the last day of the applicable
Option Period.  If ACY exercises its option, the Parties agree to negotiate in
good faith the terms and conditions of the Improvement License providing for ACY
to make, have made, use, sell, have sold and otherwise commercialize ACY
Products.  Each Improvement License shall provide (i) that ACY shall pay to
OraPharma a royalty of [the confidential material contained herein has been
omitted and has been separately filed with the commission.] and (ii) such other
terms and conditions as shall be mutually agreed to by the Parties.


     80   TERM.

          8.1  Term.  This Agreement shall be effective from the Effective Date
               ----
and, unless sooner terminated in accordance with the provisions of this Section
8, shall continue until the expiration date of the last to expire of any issued
patent included within the ACY Patent Rights having claims covering the
manufacture, use or sale of any Product, at which time OraPharma shall have a
fully paid-up non-cancellable license under all ACY Patent Rights and ACY
Technology.

          8.2  Events of Default.  Each Party shall have the right to terminate
               -----------------
this Agreement upon the occurrence of any of the following events (each, an
"Event of Default") with respect to the other (the "Defaulting Party"):  (i) a
-----------------                                   ----------------
decree or order shall have been entered by a court of competent jurisdiction
adjudging the Defaulting Party bankrupt or insolvent, or approving as properly
filed a petition seeking reorganization, readjustment, arrangement, composition
or similar relief for the Defaulting Party under any bankruptcy law or any other
similar applicable statute, law or regulation, or a decree or order of a court
of competent jurisdiction shall have been entered for the appointment of a
receiver or liquidator or trustee or

                                       19
<PAGE>

assignee in bankruptcy or insolvency of the Defaulting Party or a substantial
part of its property, or for the winding up or liquidation of its affairs; or
(ii) the Defaulting Party shall institute proceedings to be adjudicated a
voluntary bankrupt, or shall consent to the filing of a bankruptcy petition
against it, or shall file a petition or answer or consent seeking
reorganization, readjustment, arrangement, composition, liquidation or similar
relief under any bankruptcy law or any other similar applicable statute, law or
regulation, or shall consent to the appointment of a receiver or liquidator or
trustee or assignee in bankruptcy or insolvency of it or of a substantial part
of its property, or shall make an assignment for the benefit of creditors, or
shall be unable to pay its debts generally as they become due; or (iii) any
representation or warranty made by the Defaulting Party in this Agreement shall
be incorrect or untrue in any material respect; or (iv) the Defaulting Party
dissolves or ceases to exist (without a successor or assign) as a going concern;
or (v) the Defaulting Party shall commit a material breach of the terms of this
Agreement and such material breach is not cured within thirty (30) days after
written notice thereof is given by the other Party to the Defaulting Party. The
failure by OraPharma to pay ACY any royalties or other payments when due and
payable in accordance with the provisions of Section 5 hereof shall be deemed a
material breach of this Agreement.

          8.3  Termination.  Each Party may terminate this Agreement upon the
               -----------
occurrence of any Event of Default by or with respect to the other Party by
giving written notice thereof to the other Party, which notice shall
specifically identify the reason(s) for such termination.  OraPharma shall have
the right to terminate this Agreement for any reason, with or without cause,
upon not less than sixty (60) days' prior written notice to ACY.  In addition,
either Party may terminate this Agreement, by giving written notice to the other
party, in the event that the other Party shall (i) commence or participate in
any action or proceeding (including, without limitation, any patent opposition
or re-examination proceeding), or otherwise assert in writing any claim,
challenging or denying the validity of any patent right of such Party or any
claim thereof or (ii) solicit or encourage any other Entity to commence any
action or proceeding (including, without limitation, any patent opposition or
re-examination proceeding) challenging or denying the validity of, or in any
manner infringe, any patent right of such Party or any claim thereof.  This
Agreement shall terminate effective immediately upon the giving of such notice,
or such later time as the notice of termination may specify.

          8.4  Consequences of Termination.  The termination of this Agreement
               ---------------------------
for any reason shall be without prejudice to (i) the right of ACY to receive all
amounts accrued under Section 5 hereof prior to the effective date of such
termination, (ii) the rights and obligations of the Parties pursuant to Sections
5 and 11 hereof (which shall survive the termination of this Agreement), (iii)
the confidentiality and nondisclosure obligations of the Parties pursuant to
Section 9 hereof (which shall survive the termination of this Agreement), and
(iv) any other remedies as may now or hereafter be available to any Party,
whether under this Agreement, at law, in equity or otherwise.  If this Agreement
is terminated by either Party pursuant to this Section 8, (a) OraPharma, its
Affiliates and its sublicensees shall discontinue the development, manufacture,
use and sale of Products as provided herein and (b) OraPharma, its Affiliates
and its sublicensees shall (1) cease the use of all Confidential Information of
ACY and (2) return to

                                       20
<PAGE>

ACY all documents and materials containing any Confidential Information of ACY;
provided, however, that OraPharma, its Affiliates and its sublicensees may
------------------
complete the manufacture of any work-in- process and retain and sell their
inventory of all Products then on hand or in production, subject to the
obligation of OraPharma to pay to ACY all royalties with respect to Net Sales
resulting from the sale of such Products as though this Agreement had not been
terminated.


     90   CONFIDENTIAL INFORMATION.  The Parties each recognize that the
Confidential Information of the other Party and any and all Affiliates thereof
constitutes valuable confidential and proprietary information.  Accordingly, the
Parties each agree that they and their respective Affiliates shall, during the
term of this Agreement and for a period of five (5) years after the termination
thereof for any reason, hold in confidence all Confidential Information of the
other Party (including the terms hereof) and not use the same for any purpose
other than as set forth in this Agreement nor disclose the same to any other
Entity except to the extent that it is necessary for such Party to enforce its
       ------
rights under this Agreement or if required by law or any governmental authority
(including, without limitation, any stock exchange upon which such Party's
shares or other equity securities may be traded); provided, however, if any
                                                  --------  -------
Party shall be required by law to disclose any such Confidential Information to
any other Entity, such Party shall give prompt written notice thereof to the
other Party and impose upon any Entity entitled to obtain such Confidential
Information such obligations of confidentiality as may be lawfully available;
and provided, further, that the Parties shall each be permitted to disclose such
    --------  -------
Confidential Information to the extent reasonably necessary (i) to such Party's
attorneys, accountants, consultants and other professional advisors under an
obligation of confidentiality to such Party, (ii) to such Party's banks,
financial institutions or other Entities for the purpose of raising capital or
borrowing money or maintaining compliance with agreements, arrangements and
understandings relating thereto, (iii) to regulatory authorities, (iv) to
Affiliates and sublicensees of such Party, if such Entity agrees to maintain the
confidentiality of such Confidential Information pursuant to a written
agreement, and (v) to any Entity who proposes to purchase or otherwise succeed
(by merger, operation of law or otherwise) to all of such Party's right, title
and interest in, to and under this Agreement, if such Entity agrees to maintain
the confidentiality of such Confidential Information pursuant to a written
agreement in form and substance reasonably satisfactory to the Parties.  The
standard of care required to be observed hereunder shall be not less than the
degree of care which each Party or Affiliate thereof uses to protect its own
information of a confidential nature.


     100  REPRESENTATIONS AND WARRANTIES.

          10.1  By OraPharma.  OraPharma hereby represents and warrants to ACY
                ------------
that (i) OraPharma has full legal right, power and authority to execute, deliver
and perform its obligations under this Agreement, (ii) the execution, delivery
and performance by OraPharma of this Agreement do not contravene or constitute a
default under any provision of applicable law or

                                       21
<PAGE>

of its certificate of incorporation or by-laws (or equivalent governing
documents) or of any agreement, judgment, injunction, order, decree or other
instrument binding upon OraPharma, (iii) all licenses, consents, authorizations
and approvals, if any, required for the execution, delivery and performance by
OraPharma of this Agreement have been obtained and are in full force and effect
and all conditions thereof have been complied with, and no other action by or
with respect to, or filing with, any governmental authority or any other Entity
is required in connection with the execution, delivery and performance by
OraPharma of this Agreement, except for licenses, consents, authorizations and
approvals of any regulatory or other governmental or quasi-governmental
authority necessary to manufacture, use, sell, market, import, export or
otherwise commercialize any Product, and (iv) this Agreement constitutes a valid
and binding agreement of OraPharma, enforceable against OraPharma in accordance
with its terms.

          10.2  By ACY.  ACY hereby represents and warrants to OraPharma that
                ------
(i) ACY has full legal right, power and authority to execute, deliver and
perform its obligations under this Agreement, (ii) the execution, delivery and
performance by ACY of this Agreement do not contravene or constitute a default
under any provision of applicable law or of its certificate of incorporation or
by-laws (or equivalent governing documents) or of any agreement, judgment,
injunction, order, decree or other instrument binding upon ACY or relating to
the ACY Patent Rights, (iii) all licenses, consents, authorizations and
approvals, if any, required for the execution, delivery and performance by ACY
of this Agreement have been obtained and are in full force and effect and all
conditions thereof have been complied with, and no other action by or with
respect to, or filing with, any governmental authority or any other Entity is
required in connection with the execution, delivery and performance by ACY of
this Agreement, (iv) ACY is the exclusive owner of all legal and beneficial
right, title and interest in and to the ACY Patent Rights, the ACY Technology
and the Equipment, free and clear of any lien, claim or encumbrance or other
rights of any other Entity, except that (A) ACY makes no representation or
warranty regarding patent infringement, and (B) with respect to the ACY Patent
Rights, ACY has granted to Technical Developments and Investments, Est. ("TD")
                                                                          --
certain non-exclusive license rights to its microencapsulation delivery system
pursuant to an Agreement dated as of June 26, 1986 between ACY and TD (a copy of
which Agreement is attached as Exhibit D hereto), (v) this Agreement constitutes
                               ---------
a valid and binding agreement of ACY, enforceable against ACY in accordance with
its terms, and (vi) to the best of ACY's knowledge, after diligent inquiry, none
of the information or documentation furnished to OraPharma in connection with or
otherwise relating to the ACY Patent Rights contains any untrue statement of a
material fact or omits to state a material fact necessary to make such
information or documentation not misleading.

          10.3  Survival of Representations and Warranties.  The representations
                ------------------------------------------
and warranties contained herein shall survive the execution, delivery and
performance of this Agreement by the Parties for a period of two (2) years
following the Effective Date, notwithstanding any investigation at any time made
by or on behalf of either Party.


     110  PATENTS; INFRINGEMENT OF ACY PATENT RIGHTS.

                                       22
<PAGE>

          11.1  Patents.  ACY shall file, prosecute and maintain all ACY Patents
                -------
throughout the world at its sole cost and expense.  ACY shall promptly furnish
to OraPharma copies of all patent applications, documents and correspondence
relating to all patent office actions and responses thereto and other material
correspondence from or to ACY relating to any of the ACY Patent Rights.

          11.2  Infringement Claims.
                -------------------

          11.2.1  Legal Proceedings.  Each Party will promptly advise the other
                  -----------------
of any infringements or suspected infringements of any ACY Patent Rights of
which OraPharma or ACY, as the case may be, becomes aware.  Subject to
subsection 11.2.2 below, ACY shall retain the right to elect, in its sole
discretion, which remedies to adopt with respect to any infringement or
suspected infringement of the ACY Patent Rights; and should ACY elect not to
take such action as may be reasonably requested by OraPharma to protect its
rights with respect to the Products, OraPharma may take such action as it may
desire to protect its licenses and other rights granted hereunder and otherwise
with respect to the Products, including, without limitation, the commencement or
participation in legal and patent office proceedings at OraPharma's cost and
expense.  Any proceedings commenced by OraPharma may be brought in the name of
OraPharma.  All damages and other amounts recovered by ACY as a result of legal
proceedings commenced by ACY relating to any Applicable Indication (whether
pursuant to a final judgment, by settlement or otherwise) shall be applied first
to all of the expenses paid by ACY to prosecute such proceedings, and the
remaining balance of any such recovery shall be divided equally between the
Parties.  If OraPharma elects to commence any legal proceedings with respect to
any infringement or suspected infringement of any ACY Patent Rights, OraPharma
shall be entitled to retain all damages and other amounts recovered by OraPharma
as a result of such proceedings (whether pursuant to a final judgment, by
settlement or otherwise).  ACY may, at its sole expense, participate in any
proceedings commenced by OraPharma.  If either ACY or OraPharma initiates any
action for the prosecution of infringement of any ACY Patent Rights, the other
Party shall, at the initiating Party's cost and expense, join in any legal
proceedings commenced by the other if required by law.  If ACY initiates any
action for the prosecution of infringement of any ACY Patent Rights, OraPharma
shall, at ACY's cost and expense, fully cooperate with and assist ACY in
connection therewith (including, to the extent reasonably possible, having its
employees testify and make available relevant records, papers, information,
samples and the like).  If OraPharma initiates any action for the prosecution of
infringement of any ACY Patent Rights, ACY shall provide reasonable cooperation
to OraPharma in connection therewith (including, to the extent reasonably
possible, having its employees testify and make available relevant records,
papers, information, samples and the like).

          11.2.2  ACY Obligations.  ACY shall use its diligent efforts in good
                  ---------------
faith to cause the termination of any suspected infringement by any Entity (a

"Competitor") making, using or selling a Competitive Product (as defined below)
-----------
or a process for the manufacture of a Competitive Product after becoming aware
of such infringement.  For the purpose of this subsection 11.2.2, a "Competitive
                                                                     -----------
Product" shall mean any product for use in connection with
-------
                                       23
<PAGE>

any Applicable Indication and the manufacture, use or sale of which infringes
one or more valid current claims included within the ACY Patent Rights. In the
case of suspected infringements affecting a Non-Exclusive Product only, ACY may
cause an infringement to terminate by entering into a license agreement with the
Competitor (subject to subsection 5.7.5). OraPharma shall promptly notify ACY,
in writing, of any suspected infringement by any Competitor of which it becomes
aware. If ACY has not caused a suspected infringement to cease within three (3)
months following ACY's receipt of actual knowledge thereof (the "Waiting
                                                                 -------
Period"), then the following shall apply:
------

               (i) If ACY fails to commence legal proceedings against the
     Competitor on or before the expiration of the Waiting Period and,
     thereafter, to diligently prosecute the legal proceedings to completion,
     then until such infringement is terminated, the royalties payable under
     subsection 5.5 in respect of sales of Products manufactured, used or sold
     in the country or countries in which such infringement has occurred shall
     be reduced to (a) in the case of MP [the confidential material contained
     herein has been omitted and has been separately filed with the commission.]
     and (b) in the case of all Products other than MP [the confidential
     material contained herein has been omitted and has been separately filed
     with the commission.]

               (ii) If ACY commences and diligently prosecutes legal proceedings
     against the Competitor, but the infringement by the Competitor shall not
     have terminated within two (2) years following ACY's receipt of actual
     knowledge thereof, then all royalties otherwise payable by OraPharma
     hereunder in respect of sales of Products manufactured, used or sold in the
     country or countries in which such infringement has occurred shall be
     deposited by OraPharma into an interest-bearing escrow account established
     for such purpose until the matter is finally resolved by settlement or a
     final non-appealable judgment of a court of competent jurisdiction.  If ACY
     prevails and causes the suspected infringement by a Competitor to terminate
     or if any patent in the ACY Patent Rights is held valid but is not
     infringed, then the amounts paid into escrow shall be released and paid to
     ACY.  If any of the ACY Patent Rights that provide substantial protection
     for any Product are determined to be invalid, then the amounts paid into
     escrow shall be released and paid to OraPharma.

If ACY is unable to commence legal proceedings in any country or jurisdiction
due to procedural requirements which require ACY to take certain actions prior
to the commencement of legal proceedings, then ACY shall be deemed to have
commenced legal proceedings for the purpose of this subsection 11.2.2 if ACY has
commenced and diligently pursues all actions necessary or desirable to commence
legal proceedings as soon as possible thereafter.  The Waiting Period may be
extended for a period not to exceed an additional three (3) months if ACY
represents to OraPharma, in writing, that it is preparing to commence legal
proceedings, or that it is negotiating in good faith with the Competitor, to
cause such suspected infringement to cease and that ACY reasonably believes that
it can cause the suspected infringement to cease within the extended period.

                                       24
<PAGE>

     120  INDEMNIFICATION.

          12.1  Indemnification by OraPharma.  OraPharma agrees to indemnify,
                ----------------------------
defend and hold harmless ACY and its Affiliates, and their respective directors,
officers, employees and agents (collectively, "Related Parties"), from and
                                               ---------------
against any and all claims, demands, losses, liabilities, damages, costs and
expenses (including the cost of settlement, reasonable legal and accounting fees
and any other expense for investigating or defending any actions or threatened
actions) arising out of, relating to, resulting from or otherwise in connection
with (i) any actual or alleged injury or death of any Entity or damage to any
property caused or claimed to be caused by any Product developed, manufactured
or sold by OraPharma, except to the extent that such injury, death or damage is
                      ------
caused by the negligence or willful conduct of the ACY or any of its Affiliates,
or any of their respective Related Parties, (ii) any actual or alleged injury or
death of any person or physical damage to any property caused or claimed to be
caused by the Equipment, (iii) the breach of any representation or warranty made
by OraPharma herein, (iv) the default by OraPharma in the performance or
observance of any of its obligations to be performed or observed hereunder, and
(v) any action, suit or other proceeding, or compromise, settlement or judgment,
relating to any of the foregoing matters with respect to which ACY or any of its
Affiliates, or any of their respective Related Parties, is entitled to
indemnification hereunder.  In the event such claim is made or such an action is
commenced by a third party against any such Entity entitled to seek
indemnification pursuant to this subsection 12.1, such Entity shall promptly
notify OraPharma of such claim or action and OraPharma may, at its option, elect
to assume control of the defense of such claim or action; provided, however,
                                                          --------  -------
that (a) such Entity shall be entitled to participate therein (through counsel
of its or his own choosing) at such Entity's sole cost and expense, and (b)
OraPharma shall not settle or compromise any such claim or action without the
prior written consent of such Entity (which consent shall not be unreasonably
withheld or delayed), unless such settlement or compromise includes a general
release of such Entity from any and all liability with respect thereto.

          12.2  Indemnification by ACY.  ACY agrees to indemnify, defend and
                ----------------------
hold harmless OraPharma, its Affiliates and its sublicensees, and their
respective Related Parties, from and against any and all claims, demands,
losses, liabilities, damages, costs and expenses (including the cost of
settlement, reasonable legal and accounting fees and any other expense for
investigating or defending any actions or threatened actions) arising out of,
relating to, resulting from or otherwise in connection with (i) the breach of
any representation or warranty made by ACY herein, (ii) the default by ACY in
the performance or observance of any of its obligations to be performed or
observed hereunder, and (iii) any action, suit or other proceeding, or
compromise, settlement or judgment, relating to any of the foregoing matters
with respect to which OraPharma, any of its Affiliates or any of its
sublicensees, or any of their respective Related Parties, is entitled to
indemnification hereunder.  In the event such claim is made or such an action is
commenced by a third party against any such Entity entitled to seek
indemnification pursuant to this subsection 12.2, such Entity shall promptly
notify ACY of such claim or action and ACY may, at its option, elect to assume
control of the defense of such claim or action;

                                       25
<PAGE>

provided, however, that (a) such Entity shall be entitled to participate therein
--------- --------
(through counsel of its or his own choosing) at such Entity's sole cost and
expense, and (b) ACY shall not settle or compromise any such claim or action
without the prior written consent of such Entity (which consent shall not be
unreasonably withheld or delayed), unless such settlement or compromise includes
a general release of such Entity from any and all liability with respect
thereto.


     130  LIMITATIONS ON LIABILITY.

          13.1  No Warranties.  Except as expressly set forth in Section 10 of
                -------------
this Agreement, neither Party makes any representations or warranties as to any
matter whatsoever.

          13.2  Limitations of Liability.  UNDER NO CIRCUMSTANCES SHALL EITHER
                ------------------------
PARTY BE LIABLE TO THE OTHER PARTY OR ANY OTHER ENTITY FOR ANY LOSS OF PROFITS
OR SPECIAL, CONSEQUENTIAL OR INDIRECT DAMAGES OF ANY KIND WHATSOEVER.

          13.3  Force Majeure.  No Party shall be liable for failure or delay in
                -------------
performing any of its obligations hereunder if such failure or delay is
occasioned by compliance with any governmental regulation, request or order, or
by circumstances beyond the reasonable control of the Party so failing or
delaying, including, without limitation, Acts of God, war, insurrection, fire,
flood, accident, labor strikes, work stoppage or slowdown (whether or not such
labor event is within the reasonable control of the Parties), or inability to
obtain raw materials, supplies, power or equipment necessary to enable such
Party to perform its obligations hereunder.  Each Party shall (i) promptly
notify the other Party in writing of any such event of force majeure, the
expected duration thereof and its anticipated effect on the ability of such
Party to perform its obligations hereunder, and (ii) make reasonable efforts to
remedy any such event of force majeure.


     140  MISCELLANEOUS.

          14.1  All notices, consents and other communications required or which
may be given under this Agreement shall be deemed to have been duly given (i)
when delivered by hand, (ii) three (3) days after being mailed by registered or
certified mail, return receipt requested, or (iii) when received by the
addressee, if sent by facsimile transmission or by Express Mail, Federal Express
or other express delivery service (receipt requested), in each case addressed to
a Party at its address set forth below (or to such other address as such Party
may hereafter designate as to itself by notice to the other Party hereto) :


          If to OraPharma:  OraPharma, Inc.
                            1200 Route 22 East

                                       26
<PAGE>

                            Suite 2000
                            Bridgewater, NJ 08807
                            Attn:  Chief Executive Officer
                            Telecopy:  908-806-6199

          with a copy to:   Sills Cummis Zuckerman Radin
                            Tischman Epstein & Gross, P.A.
                            One Riverfront Plaza
                            Newark, New Jersey 07102
                            Attn:  Ira A. Rosenberg
                            Telecopy: 201-643-6500

          If to ACY:        American Cyanamid Company
                            555 E. Lancaster Avenue
                            St. Davids, PA 19087
                            Attn:  President
                            Telecopy:  610-995-3390

          with a copy to:   American Cyanamid Company
                            P.O. box 8299
                            Philadelphia, PA 19101
                            Attn:  Director, Legal Division
                            Telecopy:  610-964-3811

          14.2  Amendments, etc.  This Agreement may not be amended or modified,
                ----------------
nor may any right or remedy of any Party be waived, unless the same is in
writing and signed by such Party or a duly authorized representative of such
Party.  The waiver by any Party of the breach of any term or provision hereof by
any other Party will not be construed as a waiver of any other or subsequent
breach.

          14.3  No Waiver; Remedies.  No failure or delay by any Party in
                -------------------
exercising any of its rights or remedies hereunder will operate as a waiver
thereof, nor will any single or partial exercise of any such right or remedy
preclude any other or further exercise thereof or the exercise of any other
right or remedy.  The rights and remedies of the Parties provided in this
Agreement are cumulative and not exclusive of any rights or remedies provided by
law, in equity or otherwise.

          14.4  Successors and Assigns.  This Agreement shall be binding upon
                ----------------------
and inure to the benefit of the Parties and their respective legal
representatives, successors and permitted assigns; provided, that, subject to
                                                   --------
OraPharma's rights to grant sublicenses hereunder, neither Party may assign or
otherwise transfer any of its rights, duties or obligations under this Agreement
without the prior written consent of the other Party.  Notwithstanding the
foregoing, either Party, upon prior written notice to the other Party (but
without any obligation to obtain the

                                       27
<PAGE>

consent of such other Party), may assign this Agreement or any of its rights
hereunder (i) to any Affiliate of such Party, or (ii) to any Entity who succeeds
(by purchase, merger, operation of law or otherwise) to all or substantially all
of the capital stock, assets or business of such Party, if such Entity agrees in
writing to assume and be bound by all of the obligations of such Party under
this Agreement.

          14.5  Relationship of Parties.  OraPharma and ACY are not (and nothing
                -----------------------
in this Agreement shall be construed to constitute them) partners, joint
venturers, agents, representatives or employees of the other Party, nor to
create any relationship between them other than that of an independent
contractor.  Neither Party shall have any responsibility or liability for the
actions of the other Party except as specifically provided herein.  Neither
                           ------
Party shall have any right or authority to bind or obligate the other Party in
any manner or make any representation or warranty on behalf of the other Party.

          14.6  Expenses; Further Assurances.  Unless otherwise provided herein,
                ----------------------------
all costs and expenses incurred in connection with this Agreement and the
transactions contemplated hereby shall be paid by the Party which shall have
incurred the same, and the other Party shall have no liability relating thereto.
Without limiting the generality of any provision of this Agreement, each Party
agrees that upon request of any other Party, it shall, from time to time, do any
and all other acts and things as may reasonably be required to carry out its
obligations hereunder, to consummate the transactions contemplated hereby, and
to effectuate the purposes hereof.

          14.7  Entire Agreement.  This Agreement constitutes the entire
                ----------------
agreement between the Parties and supersedes all prior proposals,
communications, representations and agreements, whether oral or written, with
respect to the subject matter hereof.

          14.8  Severability. Any term or provision of this Agreement which is
                ------------
invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such invalidity or unenforceability without
rendering invalid or unenforceable the remaining terms and provisions of this
Agreement or affecting the validity or enforceability of any of the terms or
provisions hereof in any other jurisdiction.

          14.9  Counterparts. This Agreement may be signed in any number of
                ------------
counterparts, each of which shall be deemed an original, with the same effect as
if the signatures thereto and hereto were upon the same instrument.

          14.10  Headings. The headings used in this Agreement are for
                 --------
convenience of reference only and shall not affect the meaning or construction
of this Agreement.

          14.11  Governing Law. This Agreement, including the performance and
                 -------------
enforceability hereof, shall be governed by and construed in accordance with the
laws of the State of New Jersey, without reference to the principles of
conflicts of law.  Each Party hereby

                                       28
<PAGE>

submits itself for the sole purpose of this Agreement and any controversy
arising hereunder to the exclusive jurisdiction of the courts located in the
State of New Jersey, and any courts of appeal therefrom, and waives any
objection (on the grounds of lack of jurisdiction, or forum non conveniens or
otherwise) to the exercise of such jurisdiction over it by any such courts.

     IN WITNESS WHEREOF, the Parties hereto have executed or caused their
authorized representatives to execute this Agreement as of the date first above
written.


ATTEST:                                           AMERICAN CYANAMID COMPANY


By:            /s/ Robert Dougan            By:           /s/ Robert Essner
   -------------------------------------       ---------------------------------
   Robert Dougan                                  Name: Robert Essner
                                                  Title: Vice President


ATTEST:                                           ORAPHARMA, INC.


By:   /s/ Signature illegible                     By:     /s/  Michael Kishbauch
   ----------------------------------------          ---------------------------
                                                     Name:
                                                     Title:

                                       29