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                                                                     EXHIBIT 4.4

LINE OF CREDIT AGREEMENT
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Bank One, Michigan (the "Bank"), whose address is 611 Woodward Avenue, Detroit,
Michigan 48226-3947, has approved the credit facilities listed below
(collectively, the "Credit Facilities," and, individually, as designated below)
to American Dental Technologies, Inc. (the "Borrower"), whose address is 5555
Bear Lane, Corpus Christi, TX 78405 subject to the terms and conditions set
forth in this agreement.

1.0  CREDIT FACILITIES.

     1.1  FACILITY A.  The Bank has approved a credit facility to the Borrower
          in the principal sum not to exceed $7,500,000.00 in the aggregate at
          any one time outstanding ("Facility A"). Credit under Facility A shall
          be in the form of disbursements evidenced by credits to the Borrower's
          account and shall be repayable as set forth in a Master Business
          Credit Note executed concurrently (referred to in this agreement both
          singularly and together with any other promissory notes referenced in
          this Section 1 as the "Notes"). The proceeds of Facility A shall be
          used for the following purpose: working capital. Facility A shall
          expire September 30, 2001 unless earlier withdrawn.

          The Bank agrees to review Facility A on or before September 30 of each
          year to determine whether it desires to extend Facility A for an
          additional year. The performance of the review will not obligate the
          Bank to grant any extension. Such an extension will take place at the
          Bank's sole discretion and may be conditioned upon any changes in the
          terms of Facility A which the Bank may require in its sole discretion.

     1.2  FACILITY B (PURCHASE MONEY TERM LOANS AND/OR LEASES).  The Bank has
          approved a credit facility to the Borrower in the principal sum not to
          exceed $250,000.00 in the aggregate at any one time outstanding
          ("Facility B"). Facility B shall be in the form of loans evidenced by
          the Borrower's notes on the Bank's form (referred to in this agreement
          both singularly and together with any other promissory notes
          referenced in this Section 1 as the "Notes") or lease agreements on
          the Bank's standard lease form (referred to in this agreement as the
          "Leases"), the proceeds of which shall be used to purchase equipment.
          Interest on each loan shall accrue at a rate to be agreed upon by the
          Bank and the Borrower at the time the loan is made. Rent under any
          Lease shall be in an amount to be negotiated by the Borrower and the
          Bank prior to finding of the Lease. The maturity of each note or the
          term of any Lease shall not exceed 60 months from the note date or
          lease commencement date. Notwithstanding the aggregate amount of
          Facility B stated above, the original principal amount of each loan
          shall not exceed the lesser of 80% of the cost of the equipment
          purchased with loan proceeds or $250,000.00, and the amount funded
          under each Lease shall not exceed the cost of the equipment. Facility
          B shall expire on September 30, 2000 unless earlier withdrawn.

2.0  CONDITIONS PRECEDENT.

     2.1  CONDITIONS PRECEDENT TO INITIAL EXTENSION OF CREDIT.  Before the first
          extension of credit under this agreement, whether by disbursement of a
          loan, issuance of a letter of credit, the funding of a Lease or
          otherwise, the Borrower shall deliver to the Bank, in form and
          substance to the Bank:

          A.   LOAN DOCUMENTS.  The Notes, and if applicable, the Leases, the
               letter of credit applications, the security agreement, financing
               statements, mortgage, guaranties, subordination agreements and
               any other loan documents which the Bank may reasonably require to
               give effect to the transactions described by this agreement;

          B.   EVIDENCE OF DUE ORGANIZATION AND GOOD STANDING.  Evidence
               satisfactory to the Bank of the due organization and good
               standing of the Borrower and every other business entity that is
               a party to this agreement or any other loan document required by
               this agreement;

          C.   EVIDENCE OF AUTHORITY TO ENTER INTO LOAN DOCUMENTS.  Evidence
               satisfactory to the bank that (i) each party to this agreement
               and any other loan document required by this agreement is
               authorized to enter into the transaction described by this
               agreement and the other loan documents, and (ii) the person
               signing on behalf of each party is authorized to do so; and

          D.   YEAR 2000 ASSESSMENT.  If requested by the Bank, information
               satisfactory to the Bank regarding the Borrower's plan for
               addressing Year 2000 issues. "Year 2000 Issues" means anticipated
               costs, problems and uncertainties associated with the inability
               of certain computer applications to effectively handle data
               including dates on and after January 1, 2000, as such inability
               affects the business, operations, and financial condition of the
               Borrower and of the Borrower's material customers, suppliers and
               vendors.

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     2.2  CONDITIONS PRECEDENT TO EACH EXTENSION OF CREDIT. Before any
          extension of credit under this agreement, whether by disbursement of a
          loan, issuance of a letter of credit, the funding of a Lease or
          otherwise, the following conditions shall have been satisfied:

          A.   REPRESENTATIONS. The Representations contained in this agreement
               shall be true on and as of the date of the extension of credit;

          B.   NO EVENT OF DEFAULT. No event of default shall have occurred and
               be continuing or would result from the extension of credit;

          C.   ADDITIONAL APPROVALS, OPINIONS, AND DOCUMENTS. The Bank shall
               have received such other approvals, opinions and documents as it
               may reasonably request.

3.0  FEES AND EXPENSES.

     3.1  NONUSAGE FEE. The Borrower shall pay the Bank a nonusage fee on the
          average daily unused portion of Facility A at a rate of 1/8% per
          annum, payable quarterly in arrears within 30 days of the end of the
          quarter for which the fee is owing.

     3.2  OUT-OF-POCKET EXPENSES. The Borrower shall reimburse the Bank for its
          out-of-pocket expenses, and reasonable attorney's fees (including the
          fees of in-house counsel) allocated to the Credit Facilities.

4.0  SECURITY.

     4.1  Payment of the borrowings and all other obligations under the Credit
          Facilities shall be accrued by a first security interest and/or real
          estate mortgage, as the case may be, covering the following property
          and all its additions, substitutions, increments, proceeds and
          products, whether now owned or later acquired ("Collateral"):

          A.   ACCOUNTS RECEIVABLE. All of the Borrower's accounts, chatal
               paper, general intangibles, instruments and documents (as those
               terms are defined in the Michigan Uniform Commercial Code),
               rights to refunds of taxes paid at any time to any governmental
               entity, and any letters of credit and drafts under them given in
               support of the foregoing, wherever located. The Borrower shall
               deliver to the Bank executed security agreements and financing
               statements in form and substance satisfactory to the Bank.

          B.   INVENTORY. All of the Borrower's inventory, wherever located.
               The Borrower shall deliver to the Bank executed security
               agreements and financing statements in form and substance
               satisfactory to the Bank.

          C.   EQUIPMENT. All of the Borrower's equipment, wherever located.
               The Borrower shall deliver to the Bank executed security
               agreements and financing statements in form and substance
               satisfactory to the Bank.

          D.   PATENTS, COPYRIGHTS, TRADEMARKS. All of the Borrower's present
               and future patents, copyrights and trademarks. The Borrow shall
               deliver to the Bank executed assignments, pledges and financing
               statements satisfactory to the Bank.

     4.2  No forbearance or extension of time granted any subsequent owner of
          the Collateral shall release the Borrower from liability.

     4.3  ADDITIONAL COLLATERAL/SETOFF. To further secure payment of the
          borrowings and all other obligations under the Credit Facilities and
          all of the Borrower's other liabilities to the Bank, the Borrower
          grants to the Bank a continuing security interest in: (i) all
          securities and other property of the Borrower in the custody,
          possession or control of the Bank (other than property held by the
          Bank solely in a fiduciary capacity) and (ii) all balances of deposit
          accounts of the Borrower with the Bank. The Bank shall have the right
          at any time to apply its own debt or liability to the Borrower, or to
          any other party liable for payment of the obligations under the Credit
          Facilities, in whole or partial payment of such obligations or other
          present or future liabilities, without any requirement of mutual
          maturity.




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     4.4  CROSS LIEN. Any of the Borrower's other property in which the Bank has
          a security interest to secure payment of any other debt, whether
          absolute, contingent, direct or indirect, including the Borrower's
          guaranties of the debts of others, shall also secure payment of and be
          part of the Collateral for the Credit Facilities.

5.0  AFFIRMATIVE COVENANTS. So long as any debt or obligation remains
     outstanding under the Credit Facilities, the Borrower, and each of its
     subsidiaries, if any, shall:

     5.1  INSURANCE. Maintain insurance with financially sound and reputable
          insurers covering its properties and business against those casualties
          and contingencies and in the types and amounts as shall be in
          accordance with sound business and industry practices.

     5.2  EXISTENCE. Maintain its existence and business operations as presently
          in effect in accordance with all applicable laws and regulations, pay
          its debts and obligations when due under normal terms, and pay on or
          before their due date, all taxes, assessments, fees and other
          governmental monetary obligations, except as they may be contested in
          good faith if they have been properly reflected on its books and, at
          the Bank's request, adequate funds or security has been pledged to
          insure payment.

     5.3  FINANCIAL RECORDS. Maintain proper books and records of account, in
          accordance with generally accepted accounting principles where
          applicable, and consistent with financial statements previously
          submitted to the Bank. The Bank retains the right to inspect the
          Collateral and business records related to it at such times and at
          such intervals as the Bank may reasonably require.

     5.4  NOTICE. Give prompt notice to the Bank of the occurrence of (i) any
          Event of Default, and (ii) any other development, financial or
          otherwise, which would affect the Borrower's business, properties or
          affairs in a materially adverse manner.

     5.5  COLLATERAL AUDITS. Permit the Bank or its agents to perform periodic
          audits of the Collateral. The Borrower shall compensate the Bank for
          such audits in accordance with the Bank's schedule of fees as amended
          from time to time.

     5.6  MANAGEMENT. Maintain current management.

     5.7  FINANCIAL REPORTS. Furnish to the Bank whatever information, books,
          and records the Bank may reasonably request, including at a minimum:
          (If the Borrower has subsidiaries, all financial statements required
          will be provided on a consolidated and on a separate basis.)

          A. Promptly upon (i) furnishing to the shareholders of the Borrower,
             copies of all financial statements, reports and proxy statements
             and (ii) filing with the Securities and Exchange Commission, copies
             of all registration statements and annual, quarterly, monthly or
             other regular reports, including but not limited to, the Borrower's
             and any subsidiary's 10Qs and 10Ks.

          B. Within five (5) days after filing, a signed copy of the annual tax
             return, with exhibits, of the Borrower.

     5.8  YEAR 2000 ISSUES. The Borrower will take all actions reasonably
          necessary to assure that Year 2000 Issues will not have a material
          adverse effect on the business operations or financial condition of
          the Borrower. Upon the Bank's request, the Borrower will provide the
          Bank with a description of its plan to address Year 2000 Issues,
          including updates and progress reports. Borrower will advise the Bank
          of any reasonably anticipated material adverse effect on the business
          operations or financial condition of the Borrower as a result of Year
          2000 Issues.

6.0  NEGATIVE COVENANTS.

     6.1  DEFINITIONS. As used in this agreement, the following terms shall have
          the following respective meanings:

          A. "Debt Service" means for any period, principal and interest
             payments either paid or due during that period on all debt of the
             Borrower.

          B. "EBITDA" means for any period, net income plus to the extent
             deducted in determining net income, interest expense (including but
             not limited to imputed interest on capital leases), tax expense,
             depreciation, and amortization.


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          C. "Subordinated Debt" means debt subordinated to the Bank in manner
             and agreement satisfactory to the Bank.

          D. "Tangible Net Worth" means total assets less intangible assets,
             total liabilities, and all sums owing from stockholders, members,
             or partners, as the case may be, and from officers, managers, and
             directors. Intangible assets include goodwill, patents, copyrights,
             mailing lists, catalogs, trademarks, bond discount and underwriter
             expenses, organization expenses, and all other intangibles.

      6.2 Unless otherwise noted, the financial requirements set forth in this
          section shall be computed in accordance with generally accepted
          accounting principles applied on a basis consistent with financial
          statements previously submitted by the Borrower to the Bank.

      6.3 Without the written consent of the Bank, so long as any debt or
          obligation remains outstanding under the Credit Facilities, the
          Borrower shall not: (where appropriate, covenants apply on a
          consolidated basis).

          A. DEBT. Incur, or permit to remain outstanding, debt for borrowed
             money or installment obligations, except (i) debt reflected in the
             latest financial statement of the Borrower furnished to the Bank
             prior to execution of this agreement and not to be paid with
             proceeds of borrowings or leases under the Credit Facilities and
             (ii) purchase money term loans and/or leases to acquire equipment
             in an aggregate, annual amount not to exceed $300,000.00. For
             purposes of this covenant, the sale of any accounts receivable
             shall be deemed the incurring of debt for borrowed money.

          B. GUARANTIES. Guaranties or otherwise become or remain secondarily
             liable on the undertaking of another, except for endorsement of
             drafts for deposit an collection in the ordinary course of
             business.

          C. LIENS. Create or permit to exist any lien on any of its property,
             real or personal, including but not limited to copyrights, patents
             and trademarks, except: existing liens known to the Bank; liens to
             the Bank; liens incurred in the ordinary course of business
             securing current nondelinquent liabilities for taxes, worker's
             compensation, unemployment insurance, social security and pension
             liabilities; and liens for taxes being contested in good faith.

          D. TANGIBLE NET WORTH PLUS SUBORDINATED DEBT. Permit its Tangible Net
             Worth plus Subordinated Debt to be less than $7,500,000.00.

          E. LEVERAGE RATIO. Permit the ratio of its total liabilities to its
             Tangible Net Worth plus Subordinated Debt to exceed 1.50 to 1.00.

          F. CASH FLOW COVERAGE RATIO. For each fiscal quarter, permit the ratio
             of the Borrower's EBITA to its Debt Service, determined as of the
             end of that quarter, to be less than 2.00 to 1.00.

7.0    REPRESENTATIONS BY BORROWER. Each Borrower represents that: (a) the
       execution and delivery of this agreement, the Notes, and the Leases and
       the performance of the obligations they impose do not violate any law,
       conflict with any agreement by which the Borrower is bound, or require
       the consent or approval of any governmental authority or other third
       party; (b) this agreement, the Notes, and the Leases are valid and
       binding agreements, enforceable in accordance with their terms; and (c)
       all balance sheets, profit and loss statements, and other financial
       statements furnished to the Bank are accurate and fairly reflect the
       financial condition of the organizations and persons to which they apply
       on their effective dates, including contingent liabilities of every type,
       which financial condition has not changed materially and adversely since
       those dates. Each Borrower, if other than a natural person, further
       represents that: (a) it is duly organized, existing and in good standing
       under the laws of the jurisdiction under which it was organized; and (b)
       the execution and delivery of this agreement, the Notes, and the Leases
       and the performance of the obligations they impose (i) are within its
       powers; (ii) have been duly authorized by all necessary action of its
       governing body; and (iii) do not contravene the terms of its articles of
       incorporation or organization, its bylaws, or any partnership, operating
       or other agreement governing its affairs.

8.0    DEFAULT/ACCELERATION.

     8.1  EVENTS OF DEFAULT/ACCELERATION. If any of the following events occurs,
          the Credit Facilities shall terminate and all borrowings and other
          obligations under them shall be due immediately, without notice, at
          the Bank's option whether or not the Bank has made demand.

          A. The Borrower or any guarantor of any of the Credit Facilities, the
             Notes or the Leases ("Guarantor") fails to pay when due any amount
             payable under the Credit Facilities or under any agreement or
             instrument evidencing debt to any creditor.



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          B.   The Borrower or any Guarantor (a) fails to observe or perform any
               other term of this agreement, the Notes, or the Leases; (b) makes
               any materially incorrect or misleading representation, warranty,
               or certificate to the Bank; (c) makes any materially incorrect or
               misleading representation in any financial statement or other
               information delivered to the Bank; or (d) defaults under terms of
               any agreement or instrument relating to any debt for borrowed
               money (other than borrowings under the Credit Facilities) such
               that the creditor declares the debt due before its maturity;

          C.   There is a default under the terms of any loan agreement,
               mortgage, security agreement or any other document executed as
               part of the Credit Facilities, or any guaranty of the obligations
               under the Credit Facilities becomes unenforceable in whole or in
               part, or any Guarantor fails to promptly perform under its
               guaranty;

          D.   A "reportable event" (as defined in the Employee Retirement
               Income Security Act of 1974 as amended) occurs that would permit
               the Pension Benefit Guaranty Corporation to terminate any
               employee benefit plan of the Borrower or any affiliate of the
               Borrower;

          E.   The Borrower or any Guarantor becomes insolvent or unable to pay
               its debts as they become due;

          F.   The Borrower or any Guarantor (a) makes an assignment for the
               benefit of creditors; (b) consents to the appointment of a
               custodian, receiver or trustee for it or for a substantial part
               of its assets; or (c) commences any proceeding under any
               bankruptcy, reorganization, liquidation or similar laws of any
               jurisdiction;

          G.   A custodian, receiver or trustee is appointed for the Borrower
               or any Guarantor or for a substantial part of its assets without
               its consent and is not removed within 60 days after such
               appointment;

          H.  Proceedings are commenced against the Borrower or any Guarantor
              under any bankruptcy, reorganization, liquidation, or similar
              laws of any jurisdiction, and such proceedings remain undismissed
              for 60 days after commencement; or the Borrower or Guarantor
              consents to the commencement of such proceedings;

          I.  Any judgment is entered against the Borrower or any Guarantor, or
              any attachment, levy or garnishment is issued against any property
              of the Borrower or any Guarantor;

          J.  The Borrower or any Guarantor dies;

          K.  The Borrower or any Guarantor, without the Bank's written
              consent, (a) is dissolved, (b) merges or consolidates with any
              third party, (c) leases, sells or otherwise conveys a material
              part of its assets or business outside the ordinary course of
              business, (d) leases, purchases, or otherwise acquires a material
              part of the assets of any other corporation or business entity,
              except in the ordinary course of business, or (e) agrees to do any
              of the foregoing, (notwithstanding the foregoing, any subsidiary
              may merge or consolidate with any other subsidiary, or with the
              Borrower, so long as the Borrower is the survivor);

          L.  The loan-to-value ratio of any pledged securities at any time
              exceeds N/A%, and such excess continues for five (5) days after
              notice from the Bank to the Borrower;

          M.  There is a substantial change in the existing or prospective
              financial condition of the Borrower or any Guarantor which the
              Bank in good faith determines to be materially adverse; or

          N.  The Bank in good faith shall deem itself insecure;

          O.  The acquisition by any Person (as defined below), or two or more
              Persons acting in concert, of beneficial ownership (within the
              meaning of Rule 13d.3 of the Securities and Exchange Commission
              under the Securities Exchange Act of 1934) of 20% or more of the
              outstanding shares of voting stock of the Borrower. For purposes
              of this covenant, "Person" means any  natural person, corporation,
              firm, joint venture, partnership, association, limited liability
              company, enterprise, trust or other entity or organization, or any
              government or political subdivision or any agency, department of
              instrumentality thereof.

     8.2  REMEDIES. If the borrowings and all other obligations under the
Credit Facilities are not paid at maturity, whether by demand, acceleration or
otherwise, the Bank shall have all of the rights and remedies provided by any
law or agreement. Any requirement of reasonable notice shall be met if the Bank
sends the notice to the Borrower at least seven (7) days prior to the date of
sale, disposition or other event giving rise to the required notice. The Bank
is authorized to cause all or any part of the Collateral to be transferred to
or registered in its name or in the name of any other person, firm or
corporation, with or without designation of the capacity of such nominee. The
Borrower shall be liable for any deficiency remaining after disposition of any
Collateral. The Borrower is liable to the Bank for all reasonable costs and
expenses of every kind incurred in the making or collection of the Credit
Facilities, including, without limitation, reasonable attorney's fees and court
costs (whether attributable to the Bank's in-house or outside counsel). These
costs and expenses shall include, without limitation, any costs or expenses
incurred by the Bank in any bankruptcy, reorganization, insolvency or other
similar proceeding.

9.0  MISCELLANEOUS.

     9.1  Notice from one party to another relating to this agreement shall be
deemed effective if made in writing (including telecommunications) and
delivered to the recipient's address, telex number or fax number set forth
under its name below by any of the following means: (a) hand delivery, (b)
registered or certified mail, postage prepaid, with return receipt requested,
(c) first class or express mail, postage prepaid, (d) Federal Express or like
overnight courier service

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          or (e) fax, telex, or other wire transmission with request for
          assurance of receipts in a manner typical with respect to
          communication of that type. Notices made in accordance with this
          section shall be deemed delivered upon receipt, if delivered by hand
          or wire transmission, 3 business days after mailing if mailed by first
          class, registered of certified mail, or one business day after mailing
          or deposit with an overnight courier service if delivered by express
          mail or overnight courier.

     9.2  No delay on the part of the Bank in the exercise of any right or
          remedy shall operate as a waiver. No singer or partial exercise by the
          Bank of any right or remedy shall preclude any other future exercise
          of it or the exercise of any other right or remedy. No waiver or
          indulgence by the Bank of any default shall be effective unless in
          writing and signed by the Bank, nor shall a waiver on one occasion be
          construed as a bar to or waiver of that right on any future occasion.

     9.3  This agreement, the Notes, the Leases and any related loan documents
          embody the entire agreement and understanding between the Borrower and
          the Bank and supersede all prior agreements and understandings
          relating to their subject matter. If any one or more of the
          obligations of the Borrower under this agreement, the Notes or the
          Leases shall be invalid, illegal or unenforceable in any jurisdiction,
          the validity, legality and enforceability of the remaining obligations
          of the Borrower shall not in any way be affected or impaired, and such
          invalidity, illegality or unenforceability in one jurisdiction shall
          not affect the validity, legality or enforceability of the obligations
          of the Borrower under this agreement, the Notes or the Leases in any
          other jurisdiction.

     9.4  The Borrower, if more than one, shall be jointly and severally liable.

     9.5  This agreement is delivered in the State of Michigan and governed by
          Michigan law. This agreement is binding on the Borrower and its
          successors, and shall inure to the benefit of the Bank, its successors
          and assigns.

     9.6  Section headings are for convenience of reference only and shall not
          affect the interpretation of this agreement.

10.0 Waiver of Jury Trial. The Bank and the Borrower knowingly and voluntarily
     waive any right either of them have to a trial by jury in any proceeding
     (whether sounding in contract or tort) which is in any way connected with
     this or any related agreement, or the relationship established under them.
     This provision may only be modified in a written instrument executed by the
     Bank and the Borrower.

Executed by the parties on: September 30, 1999.

Bank One, Michigan                      Borrower: American Dental Technologies,
                                                  Inc.

By: /s/ JAMES E. WOLFINGTON             By: /s/ BEN J. GALLENT
    -------------------------------         -----------------------------------
    James E. Wolfington,                    Ben J. Gallent, President
    Vice President


Address for Notices                     Address for Notices

28660 Northwestern Highway              5555 Bear Lane
Southfield, Michigan 48034              Corpus Christi, Texas 78405

Fax/Telex No. (248) 799-5826            Fax/Telex No.



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