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                                                                   EXHIBIT 10.46

                       UNITED DENTAL CARE OF ARIZONA, INC.
                            FAMILY DENTIST AGREEMENT

     This Agreement is made this 31st day of December, 1997, by and between
United Dental Care of Arizona, Inc. (the "Plan"), and Associated Dental Care
Providers, P.C., an Arizona professional corporation (the "Dental Group").

                             Background Information

     A. The Plan has organized a Managed Dental Benefits program in the State of
Arizona and desires to make contractual arrangements for its Members
(hereinafter defined) under which Dental Group agrees to provide dental care to
Members.

     B. The Plan and the Dental Group (the "Parties") are currently parties to a
Family Dentist Agreement dated January 21, 1997 (the "Provider Agreement") and
an Agreement Regarding Facility Financing dated January 21, 1997 (the "Facility
Financing Agreement"). The Parties desire to modify their relationship for the
mutual benefit of each of them and are entering into this Agreement for that
purpose.

     C. Dental Group is willing to enter into this Agreement with the Plan and
provide dental care to Members upon the terms and conditions herein contained.

                                    Agreement

     The Parties acknowledge the accuracy of the foregoing Background
Information and hereby agree as follows:

                             ARTICLE I - DEFINITIONS

1.1  Dental Group: shall mean Associated Dental Care Providers, P.C., an Arizona
     professional corporation.

1.2  Dental Director: shall mean the dentist appointed by the Plan to promulgate
     and maintain professional standards for the dentists contracting with the
     Plan.

1.3  Dental Service Agreement: shall mean the dental service agreement between
     the Plan and an employer group or, in the case of an individual, the
     agreement between a Member and the Plan.

1.4  Emergency Dental Services: shall mean those services required for
     alleviation of severe pain, bleeding and swelling, or immediate diagnosis
     and treatment of unforeseen dental conditions which, if not treated, would
     jeopardize or impair the dental health of the Member.

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1.5  United Dental Care of Arizona, Inc.: (herein referred to as the "Plan")
     shall mean an Arizona corporation operating pursuant to statutes and
     regulations of the state which arranges for the provision of dental
     services to Members that are set forth herein.

1.6  Member: shall mean subscriber and all eligible dependents enrolled pursuant
     to Dental Service Agreement.

                      ARTICLE II - RELATIONSHIP OF PARTIES

2.1  Basic Relationship: The Plan and the Dental Group are separate and
     independent entities. Dental Group shall render its services under this
     Agreement as an independent contractor. As independent contracting parties,
     the Plan and the Dental Group maintain separate and independent management,
     and each has full unrestricted authority and responsibility regarding its
     own organization and structure. Nothing contained herein shall be deemed or
     construed to make Dental Group, or any of its employees or other persons
     acting under its direction or control, an agent, employee, servant,
     partner, or joint venturer of or with the Plan.

                      ARTICLE III - DUTIES OF DENTAL GROUP

3.1  Duties: Dental Group agrees to:

     A.   Subject to Section 7.4, below, provide those dental services set forth
          in Exhibit A hereto, for all Members selecting or assigned to Dental
          Group, subject to any Exclusions and Limitations;

     B.   Refer Members for appropriate specialty care, where needed, and not
          provided by Dental Group, as set forth in Exhibit A. Any such
          referrals for specialty care must be in compliance with the Plan's
          specialty care referral system (as currently in effect and as modified
          as required by applicable law, with prompt notice of such modification
          provided in writing to Dental Group, or as mutually agreed upon by the
          Parties in writing) and authorization in advance by Dental Director or
          his designee;

     C.   Provide twenty-four (24) hour Emergency Dental Services coverage at
          all times. In the event that, upon proper notification of Dental Group
          by a Member requiring Emergency Dental Services, Dental Group is not
          available to provide any such Emergency Dental Service required by
          such Member, and the Plan incurs any expenses for such covered
          Emergency Dental Service, Dental Group will be responsible for
          reimbursing Plan for any such reasonable expenses, if so deemed by the
          Plan's Provider Relations Manager or Provider Relations
          Representative.

     D.   Conduct its relationship with the Plan and Members in a professional
          and positive manner, and not make untruthful or otherwise disparaging
          statements regarding its relationship with the Plan, Members or the
          Plan's business;


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          provided that this provision shall not prevent the Dental Group from
          making any disclosures or statements required by applicable law.

     E.   Comply with all provisions of the Plan's Dentist Office Reference
          Manual, as currently in effect and as modified as required by
          applicable law, with prompt notice of such modification provided in
          writing to Dental Group, or as mutually agreed upon by the Parties in
          writing.

3.2  Discrimination: Dental Group shall not differentiate or discriminate in the
     treatment of its patients by reason of the fact that certain of those
     patients are Members. Dental Group shall render dental services to Members
     in the same manner, in accordance with the same standards, and with the
     same time availability as offered its other patients, subject to any
     contrary requirements of the Dental Service Agreement or this Agreement.

3.3  Administration. To enable the Plan to implement appropriate quality
     assurance programs, Dental Group shall:

     A.   Cooperate with the Plan in maintaining and providing such dental,
          financial, administrative and other records relating to a Member as
          may be reasonably requested by the Plan. When Plan requests records,
          the Plan shall have obtained the proper releases from the Patient.
          When provided to the Plan, these records shall maintain the
          confidential nature they had while in the possession of Dental Group;

     B.   Cooperate and participate with the Plan in quality assurance, peer
          review and audit systems, service standards and grievance procedures,
          as reasonably set forth by the Plan, and, to the extent required by
          applicable law, comply with all final determinations rendered by the
          peer review process and grievance resolution process established by
          the Plan, provided that the Plan hereby acknowledges that, as of the
          date of this Agreement, Dental Group is in full compliance with the
          requirements of this Section 3.3B; and

     C.   Cooperate with the Plan in maintaining records and files relating to
          Dental Group by informing the Plan in writing of any changes to the
          information provided to the Plan on the Dental Group Application.

     The foregoing requirements of this section shall be subject in all cases to
     the requirements of applicable law, including without limitation
     confidentiality requirements.

3.4  Confidentiality: Dental records of Members shall be treated as confidential
     in order to comply with all federal and state laws and regulations
     regarding the confidentiality of patient records. Dental Group and Plan
     agree to maintain the confidentiality of the Members' records and
     enrollment information, and prevent unauthorized disclosure, as required by
     applicable law.


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3.5  Dental Audit. Subject to the requirements of applicable law, Dental Group
     agrees to permit, upon reasonable prior notice from the Plan, reasonable
     inspection and audit of dental records of Members by the Plan, and to
     comply with reasonable requirements issued as a result of such inspection
     or audit; provided that Plan shall cause legally adequate permission to
     inspect dental records to be granted by all Members by their signature on
     the company Plan enrollment form, in accordance with federal and state laws
     and regulations.

3.7  Utilization and Specialty Referrals. Dental Group agrees to submit
     utilization information on at least a monthly basis, in a mutually agreed
     upon electronic format, and to comply with all material requirements of the
     Plan's specialty care referral system, as currently in effect and as
     modified as required by applicable law, with prompt notice of such
     modification provided in writing to Dental Group, or as mutually agreed
     upon by the Parties in writing.

3.8  Grievance. Dental Group agrees to comply with the Plan's grievance
     resolution procedures as currently in effect and as modified as required by
     applicable law, with prompt notice of such modification provided in writing
     to Dental Group, or as mutually agreed upon by the Parties in writing;
     provided that the Plan hereby acknowledges that, as of the date of this
     Agreement, Dental Group is in full compliance with the requirements of this
     Section 3.8. Dental Group shall abide by the decisions of the Plan's
     grievance review committee to the extent required by applicable law.

3.9  License: The Dental Group represents and warrants that the Dental Group and
     all other dentists, technicians, hygienists and assistants (collectively,
     "Professional Personnel") at the Dental Group's facilities are duly and
     appropriately licensed under applicable state law, and shall maintain such
     licenses in good standing throughout the term of this Agreement; that all
     equipment used in the rendering of dental services under this Agreement and
     required to be licensed or certified is duly and appropriately licensed
     under state law; and that the Dental Group has the staff, personnel and
     facilities to provide dental services as described in this Agreement and
     the Dental Service Agreements. If any Professional Personnel not affiliated
     with Dental Group as of the date of this agreement become affiliated with
     Dental Group after the date of this agreement (whether as an employee,
     independent contractor, or otherwise), Dental Group shall, within 30 days
     after such affiliation begins, provide Plan with evidence that such
     Professional Personnel are duly and appropriately licensed under applicable
     state law; provided that Dental Group's obligation under this sentence
     shall be deemed satisfied, such 30-day period notwithstanding, if Dental
     Group provides such evidence at any time in compliance with Plan's
     credentialing policies and procedures as contemplated by other provisions
     of this agreement. The Parties understand and agree that inclusion of
     Dental Group on Plan's panel of dentists is not a recommendation of Dental
     Group.




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3.10 Telephone Eligibility Confirmation. If a patient claiming to be a Member
     but not listed in the then-most-recent eligibility list provided by the
     Plan to the Dental Group requests dental services from the Dental Group,
     the Dental Group shall telephone the Plan, and the Plan shall inform the
     Dental Group as to whether the patient is or is not a Member assigned to
     Dental Group and shall immediately send written confirmation of such to the
     Dental Group by fax. If the patient is a Member, Plan shall promptly pay
     Dental Group any unpaid capitation on a per member per month basis for such
     Member retroactive to the date the Member was assigned to Dental Group.
     Dental Group shall not unreasonably withhold dental treatment from any
     Member so verified and shall schedule appointments pursuant to Section 3.2.

3.11 Complaint Ratio. The Dental Group shall have a rate of complaints per
     Member assigned to Dental Group that does not exceed the customary rate of
     other dentists located in the community.

                         ARTICLE IV - DUTIES OF THE PLAN

4.1  Eligibility List: The Plan agrees to provide the Dental Group, by the fifth
     of each calendar month, with a listing of Members eligible for services in
     the Dental Group's facilities for the current month. In addition, the Plan
     agrees to provide the Dental Group, from time to time at the reasonable
     request of the Dental Group, with an audit to validate the accuracy of the
     eligibility list.

4.2  Eligibility Audit: The Plan agrees to permit the Dental Group, upon
     reasonable prior notice, to inspect and audit Plan Member's records
     relating to eligibility and capitation or other payments of the Dental
     Group, and to comply with reasonable requirements issued as a result of
     such inspection or audit.

4.3  License: The Plan represents and warrants to the Dental Group that the Plan
     is a duly licensed prepaid dental plan organization in the State of Arizona
     with full power and authority to perform its obligations under this
     Agreement and the Dental Service Agreements and shall continue to be so
     licensed and maintain such license during the term of this Agreement.

                        ARTICLE V - SELECTION OF DENTIST

5.1  Selection: At the time of enrollment, all Members are requested to select a
     dentist who will provide or arrange for the provision of all covered dental
     services. The Plan agrees to list the Dental Group and any affiliated
     dentists, if applicable, as authorized dentists of the Plan in its
     materials to all Members, and dentists under the control of Dental Group
     hereby agree to allow the Plan to so list them.


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5.2  Acceptance of Members: Dental Group agrees to accept all Members under the
     Plan's dental benefits plans currently covered by this Agreement and
     hereafter approved by the Dental Group. In the event that any Dental Group
     facility becomes too full to accommodate additional new patients, Dental
     Group may request the Plan to inactivate such facility from further new
     Member selection (subject to Exhibit A, Paragraph 3). In the event that
     Dental Group has met all material obligations of this Agreement and
     continues in material compliance, the Plan shall not unreasonably withhold
     approval of such a request. Dental Group shall then provide a 90-day
     inactivation notice to the Plan with respect to such facility and such
     inactivation shall be effective the first of the month following the
     completion of the 90-day period, or such earlier date that Dental Group and
     the Plan may mutually agree in writing. In the event that the Plan
     authorizes such inactivation for such facility, such facility will then be
     removed from all future lists of selectable dentists in the Plan's
     materials, subsequent to the effective date of such notice, and Dental
     Group may only then refuse to accept Members at such facility other than
     those who have already selected, or been assigned to, it. Prior to the
     effective date of any such approval by the Plan and during that 90-day
     notice period, Dental Group shall accept any and all new Members selecting
     Dental Group at such facility, and shall render treatment and services to
     all Members subject to the terms of this Agreement.

5.3  Patient Relationship. The Dental Group shall be solely responsible for all
     dental advice and services rendered to a Member. The Dental Group shall
     maintain a dentist-patient relationship, without any interference by the
     Plan whatsoever, with each Member served.

5.4  Transfer of Patients. Subject to Section 12.2, below, because the
     dentist-patient relationship is personal and may become unacceptable to
     either of them, Member or Dental Group may request in writing or via phone
     call to the customer service center that the Member be transferred to
     another provider. Where practical, such transfer will be made, as solely
     determined by the Plan.

                         ARTICLE VI - QUALITY ASSURANCE

6.1  Standards. Dental Group agrees to provide services to Members with the same
     standards of care, skill and diligence that are customarily used by
     dentists located in the community where such services are rendered, in
     accordance with the policies and procedures established by the Dental
     Director of the Plan as currently in effect and as modified as required by
     applicable law, with prompt notice of such modification provided in writing
     to Dental Group, or as mutually agreed upon by the Parties in writing, and
     in accordance with "Principles of Ethics of the American Dental
     Association" and the laws of the State of Arizona, provided that the Plan
     hereby acknowledges that, as of the date of this Agreement, Dental Group is
     in full compliance with the requirements of this Section 6.1.

6.2  Quality Assurance. The Plan, in consulting with its Dental Director, shall
     develop, implement and maintain a quality assurance program, policies and
     procedures and service standards consistent with other programs, policies,
     procedures and standards required by Plan of other dental care providers in
     the Plan's provider network. Dental Group shall be


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     bound by and comply with such policies and procedures and service standards
     as currently in effect and as modified as required by applicable law, with
     prompt notice of such modification provided in writing to Dental Group, or
     as mutually agreed upon by the Parties in writing.

                           ARTICLE VII - COMPENSATION

7.1  Eligible Members. The Plan shall determine each Member who is eligible to
     receive from Dental Group the dental services set forth in Exhibit A of the
     Agreement. The Plan will notify Dental Group of Members' eligibility.
     Dental Group's obligations to provide care hereunder shall extend and be
     limited to those Members who have selected or been assigned to the Dental
     Group, who have been determined to be eligible by the Plan, and with
     respect to whom proper capitation payment has been received by Dental
     Group.

7.2  Fees. In exchange for agreeing to the provision of services to Members, the
     Plan shall pay the Dental Group the amounts shown on Exhibit A attached.
     Dental Group further agrees that all the Members are entitled to their Plan
     benefits regardless of other dental coverage. Accordingly, all Member
     copayments are due Dental Group at the time service is rendered. Dental
     Group further agrees not to charge, nor collect from, any Member fees for
     non-dental service expenses the Dental Group may incur in the normal course
     of rendering dental treatment services.

     Such non-dental service items may include, but are not limited to,
     sterilization methods and materials; office or dental supplies with the
     exception of gold; any equipment or instruments necessary for treatment; or
     other general overhead expenses.

     Dental Group hereby agrees that in no event, including, but not limited to
     non-payment by the Plan, Plan insolvency or breach of this Agreement, shall
     Dental Group bill, charge, collect a deposit from, seek compensation,
     remuneration or reimbursement from, or have any recourse against any Member
     or person other than the Plan acting on their behalf for services provided
     pursuant to this Agreement. This provision shall not prohibit collection of
     supplemental charges or copayments on the Plan's behalf made in accordance
     with the terms of the Dental Service Agreement.

     Dental Group further agrees that (1) this provision shall survive the
     termination of this Agreement regardless of the cause giving rise to
     termination and shall be construed to be for the benefit of the Plan
     Member, and (2) this provision supersedes any oral or written contrary
     agreement now existing between Dental Group, Member or persons acting on
     their behalf.

7.3  Payment. Payment by the Plan shall be made monthly, by the fifth day of the
     month for which Member is eligible. Dental Group accepts compensation per
     Exhibit A and all applicable Member copayments as payment in full for
     services rendered to such Members.



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7.4  Additional Plans. The Plan may, from time to time, amend, delete or add to
     its various Dental Service Agreements, and, in such event, the Plan shall
     send Dental Group an amended Exhibit A to reflect those amendments,
     deletions or additions at the address in Section 11.0B. If Dental Group
     does not agree with any such amendments, deletions or additions, Dental
     Group shall, within 30 days after receipt of written notification from
     Plan, notify Plan in writing at the address set forth in Section 11.0A,
     and, in such event, such amendments, deletions or additions shall not
     become part of this Agreement. If Dental Group does not so notify Plan,
     then such amendments, deletions or additions shall become part of this
     Agreement.

                ARTICLE VIII - TERM AND TERMINATION OF AGREEMENT

8.1  Term. The Parties' respective obligations pursuant to this Agreement shall
     begin on January 1, 1998, and shall end on December 31, 2001 (the "Initial
     Term"), unless sooner terminated pursuant to Section 8.2, below. This
     Agreement shall automatically renew for successive one-year periods after
     the Initial Term (each, a "Renewal Term") unless and until terminated
     pursuant to Section 8.2, below.

8.2  Termination.

     A.   This Agreement may be terminated by either Party only for cause upon
          written notice, except that either Party may terminate this Agreement
          at the end of the Initial Term or any Renewal Term without cause upon
          written notice at least 90 days in advance of the end of such Term.
          After termination of this Agreement, the Dental Group shall no longer
          be obligated to provide any dental services pursuant to this Agreement
          (except as described in Section 8.3B), and the Dental Group's name
          will be removed from all future printings of Plan materials. During
          any notice period preceding termination of this Agreement, Dental
          Group shall render treatment and services to all Members of record
          subject to the terms of this Agreement.

     B.   For purposes of termination of this Agreement by the Plan, "for cause"
          shall mean a breach by the Dental Group of the representations and
          warranties set forth in the first paragraph of Section 3.9, which
          breach has or is reasonably likely to have a material adverse effect
          on the Plan and which remains uncured for 30 days after receipt by the
          Dental Group from the Plan of notice thereof. The termination of this
          Agreement by Plan shall not be deemed to be an election of remedies
          and Plan may pursue any or all other rights and/or remedies, either
          separately or cumulatively.

     C.   For purposes of termination of this Agreement by the Dental Group,
          "for cause" shall mean the Plan's failure to make any payment provided
          for by this Agreement within 10 days after it becomes due. The
          termination of this Agreement by Dental Group shall not be deemed to
          be an election of remedies and Dental Group may pursue any or all
          other rights and/or remedies, either separately or cumulatively.


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     D.   This Agreement may be terminated at any time upon the mutual written
          agreement of the Parties.

     E.   The Plan may inactivate Dental Group from further Member selection in
          the event of notice of termination of this Agreement for any reason
          permitted by this Agreement.

     F.   The Plan may transfer Members and the corresponding capitation to
          alternate Plan dentists subsequent to any termination notice but not
          prior to the termination effective date, unless Plan and Dental Group
          have mutually agreed to a transfer prior to termination effective
          date, or if termination is a result of breach by Dental Group of the
          representations and warranties set forth in Section 3.9.

8.3  Effect of Termination.

     A.   Notwithstanding any other provision in this contract, any termination
          of this Agreement shall have no effect upon the rights and obligations
          of the Parties arising out of any transactions occurring prior to the
          effective date of such termination as set forth herein.

     B.   In the event of the termination of this Agreement, Dental Group shall
          complete work started prior to the effective date of termination as
          follows:

          1.   If tooth preparation has occurred and/or an impression has been
               taken, Dental Group will complete a fixed or removable denture.

          2.   On every tooth upon which work has been started by modification
               of tooth structure.

     C.   In the event of termination of this Agreement, subject to the
          requirements of applicable law: (i) Dental Group agrees to transfer
          patient records within the guidelines and precedence of the Dental
          Group's community at the request of the Member's newly-assigned
          dentist; (ii) copies of all Member patient records and x-rays shall be
          sent within 30 days after such request; (iii) Dental Group shall be
          able to charge a reasonable fee for duplication of records and x-rays;
          and (iv) Dental Group further agrees to return all Plan materials to
          the Plan including the Dental Office Reference Manual.

     D.   Dental Group agrees to notify Members who may continue to seek
          treatment from Dental Group, subsequent to the Dental Group's
          termination date that Dental Group is no longer a participating Plan
          provider, prior to rendering any service. If such


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          notice is not given to the Member, Dental Group agrees to charge the
          Member no more for its services than would have been payable by the
          Member had this Agreement not terminated.

                   ARTICLE IX - INSURANCE AND INDEMNIFICATION

9.1  Liability Insurance. Dental Group shall carry malpractice insurance in
     amount of not less than $300,000 in the aggregate covering all dentists,
     technicians, hygienists, assistants and other employees and contractors
     engaged at the facility. At any time upon the request of Plan, Dental Group
     shall provide Plan with a Certificate of Insurance evidencing such coverage
     and providing for not less than thirty (30) days notice of reduction in
     limits, cancellation or non-renewal. Failure to deliver such certificate of
     insurance to Plan or failure to inform Plan immediately of reduction in
     limits, cancellation, or non-renewal of coverage shall be cured by Dental
     Group within 10 days.

9.2  Indemnity. The Plan agrees to indemnify and hold Dental Group harmless with
     regards to any claim, demand, liability, judgment, suit, cause of action,
     or costs and expenses (including without limitation reasonable attorneys'
     fees) arising in connection with claims made by any persons that the Plan
     or its agents acted illegally, negligently or improperly or misrepresented
     any material fact.

     In addition, Dental Group agrees to indemnify and hold Plan harmless with
     regards to any claim, demand, liability, judgment, suit, cause of action,
     or costs and expenses (including without limitation reasonable attorneys'
     fees) arising out of, or made by any person or persons in connection with
     the professional services or other acts performed by dentist and/or failure
     of dentist to complete professional services undertaken by Dental Group.

                         ARTICLE X - GENERAL PROVISIONS

10.1 Waiver. The waiver by either Party of any breach of any provision hereof on
     the part of the other shall not be construed to operate as a waiver of any
     other or subsequent breach of the same or any other term, condition or
     covenant contained in the Agreement. All rights and remedies of each Party
     under this Agreement shall be cumulative and in addition to all other
     rights and remedies which may be available to that Party from time to time,
     whether under any other agreement, at law, or in equity.

10.2 Entire Agreement. This Agreement represents the entire understanding
     between the Parties and supersedes any prior agreements or understandings
     with respect to the subject matter hereof, including without limitation the
     Provider Agreement and the Facility Financing Agreement, which are hereby
     terminated as of the commencement of the Initial Term. All amendments or
     modifications hereto shall be mutually agreed to in writing by the Plan and
     Dental Group, except as specified in Section 7.4.



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10.3  Invalidity. The invalidity or unenforceability of any term or provision of
      this Agreement shall not invalidate or render unenforceable any other term
      or provision of this Agreement.

10.4  Successors; Assignment. This Agreement shall be binding upon, inure to the
      benefit of, and be enforceable by and against the Parties and their
      respective successors and assigns, including without limitation any
      successor to either Party pursuant to a change in control of such Party.
      This Agreement shall not be assigned in whole or in part by either Party
      without the written consent of both Parties, which shall not be
      unreasonably withheld.

10.5  Terms. For simplicity of expression, pronouns and other terms are
      sometimes expressed in one number and gender, but where appropriate to the
      context these terms shall be deemed to include each of the other numbers
      and genders.

10.6  Headings. The underlined headings are for convenience and shall not be
      deemed to include each of the other numbers and genders.

10.7  Governing Law. This Agreement is governed by and shall be construed
      according to Arizona laws. Any action to enforce this Agreement shall be
      brought in Superior Court of Arizona in Pima County.

10.8  Financial Records. Dental Group and the Plan shall cooperate in keeping
      financial statistical records which may be necessary for the proper
      administration of the Plan or as required by state or federal laws and
      regulations. Such records shall be retained for a period of 5 years. Such
      obligations shall not terminate upon termination of the Agreement whether
      by rescission or otherwise.

10.9  Surcharges. Dental Group is not permitted to surcharge any Member for
      covered services and shall, whenever a surcharge has erroneously occurred,
      upon notice by that Member or the Plan, refund such charge within 5 days.

10.10 Service After Termination. Upon termination of the Agreement, the Plan
      shall be liable for covered services rendered by Dental Group (other than
      for copayments) to Members who retain eligibility in the Plan subject to
      the limitations of Section 8.3D or by operation of law who are under the
      care of Dental Group at the time of such dentally-appropriate provisions
      for the assumption of such services by another contracting dentist. Dental
      Group shall request prior approval of the Plan to perform any such
      services above.

10.11 Patient Records. Subject to the requirements of applicable law: (i) Dental
      Group shall maintain up-to-date records in accordance with accepted
      professional standards, sound dental accounting procedures and sound
      internal practices; (ii) said records shall reflect the date each Member
      was seen, the procedures followed, and the name, address, and specialty of
      each specialist or another dentist to whom he was referred; (iii) such
      records shall be made available for inspection by the Plan during regular
      business hours and other reasonable times; and (v) the Plan shall from
      time to time provide forms for keeping utilization records, which shall be
      submitted to the Plan as requested by the Plan.


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10.12 Non-Solicitation. Dental Group agrees that, during the term of this
      Agreement and for the one-year period following termination of this
      Agreement (other than termination by Dental Group for cause pursuant to
      Section 8.2C), Dental Group shall not solicit or otherwise approach then
      current Members of the Plan to become members in a prepaid dental plan,
      preferred provider organization or any other managed dental delivery
      system (other than the Plan) to which Dental Group is a provider or has an
      ownership interest, nor shall Dental Group in any fashion encourage any
      Member to terminate from the Plan; provided that Dental Group shall not be
      prohibited from soliciting any Member for the purpose of providing dental
      services to such Member on a fee-for-service basis; and provided further
      that this Section 10.12 shall not prohibit Dental Group from soliciting
      then current Members at any time after the Plan has been given notice of
      termination of the Dental Service Agreement applicable to such Member.

10.13 Dentist Manual. Dental Group acknowledges that prior to or concurrent with
      the execution of this Agreement Dental Group received a Dental Office
      Reference Manual. Dental Group understands and agrees that Manual is
      proprietary to Plan and confidential in nature. Dental Group agrees not to
      reproduce any portion of the Manual or otherwise disclose any of its terms
      or provisions to any person not directly affiliated with the facility
      absent the express written permission of the Plan. Upon termination of
      this Agreement, Dental Group agrees to promptly return Dental Group's copy
      of the Manual, and any and all supplements, to the Plan.

10.14 Radiology Equipment. If Dental Group utilizes radiological or radiographic
      equipment at its facilities in rendering services pursuant to this
      Agreement, Dental Group shall have such equipment regularly checked by
      local or state health authorities or a radiation physicist to insure that
      such equipment is environmentally safe and technologically accurate. Any
      hazards identified by such inspections or at any time shall be promptly
      corrected. Dental Group shall maintain equipment maintenance and
      calibration records and all inspection certificates or reports which shall
      be available for review by Plan upon request.

10.15 Arizona Regulatory Matters. Dental Group understands and acknowledges
      that, pursuant to applicable Arizona law, the Plan is required to file
      this agreement with the Arizona Department of Insurance (or such other
      Arizona government agency as may be appropriate) (the "Arizona DOI"). In
      the event that the Arizona DOI makes a determination based on such filing
      that this agreement is unlawful, or in the event of any change in any
      statute, law, regulation, legislation, rule, policy, or general
      instruction subject to the administration of the Arizona DOI
      (collectively, a "ruling"), which materially and adversely affects, or is
      reasonably likely so to affect, the manner in which either Party is to
      perform or be compensated for its services under this agreement or which
      shall make this agreement unlawful, the Parties shall immediately use
      their best efforts to enter in a new agreement that complies with such
      determination or ruling and approximates as closely as possible the
      obligations and economic position of the Parties prior to such
      determination or ruling.


<PAGE>   13



                              ARTICLE XI - NOTICES

11.0  Notices. All notices and other communications under this agreement to any
      Party shall be in writing and shall be deemed given when delivered
      personally, telecopied (which is confirmed) to that Party at the telecopy
      number for that Party set forth below, mailed by certified mail (return
      receipt requested) to that Party at the address for that Party (or at such
      other address for such Party as such Party shall have specified in notice
      to the other Party) or delivered to Federal Express, UPS, or any similar
      express delivery service for delivery to that Party at that address:

      A.    If to the Plan:               United Dental Care of Arizona, Inc.
                                          1702 E. Highland Avenue, Suite 110
                                          Phoenix, AZ 85016
                                          Telecopy: (602) 263-0187

            Or:                           United Dental Care, Inc.
                                          13601 Preston Road, Suite 500
                                          Dallas, Texas 75240
                                          Attn: President
                                          Telecopy: (972) 458-7963

      B.    If to the Dental Group:       Joseph V. Errante, D.D.S.
                                          Associated Dental Care Providers, P.C.
                                          2100 N. Kolb Rd., Ste. 105
                                          Tucson, Arizona 85715
                                          Telecopy: (520) 290-9317

            With a copy to:               Gregory A. Serrao, President
                                          American Dental Partners, Inc.
                                          301 Edgewater Place, Suite 320
                                          Wakefield, Massachusetts 01880-1249
                                          Telecopy: (781) 224-4216


                       ARTICLE XII - ADDITIONAL PROVISIONS

12.1  Prior Loans. Plan hereby forgives the outstanding principal balance on the
      loans made pursuant to the Facility Financing Agreement.

<PAGE>   14


12.2  Assignment of Additional Members. The Parties agree and acknowledge that,
      as of the date of this Agreement, there are approximately 32,000 Members
      assigned to the Dental Group's current facilities. By April 1, 1998, Plan
      shall assign at least 20,000 additional Members to Dental Group's current
      facilities. Both Parties shall cooperate in the selection of Dental Group
      facilities to which such additional Members are assigned, and, except at
      the Member's request, Plan shall not reassign any Member that has selected
      one of Dental Group's facilities and/or a dentist employed by or
      associated with Dental Group.

12.3  Maintenance of Provider Network. Dental Group shall continue to support
      Plan's efforts to maintain an attractive provider network in Arizona and
      shall assist Plan in increasing its membership.

12.4  Non-Exclusivity. Except as described in Exhibit A, Paragraph 7, the
      Parties' relationship pursuant to this Agreement shall not be exclusive.

12.5  Contingency. Each Party's obligations under this Agreement shall be
      contingent upon completion of the purchase of all of the outstanding
      capital stock of Innovative Practice Concepts, Inc., an Arizona
      corporation, by American Dental Partners, Inc., a Delaware corporation,
      and in the event such purchase is not completed the Provider Agreement and
      Facility Financing Agreement shall not be terminated and shall remain in
      full force and effect.

THIS AGREEMENT is executed in several counterparts. Each is hereby declared to
be an original; however, all shall constitute but one and the same Agreement.

IN WITNESS WHEREOF, the Parties have duly executed this Agreement on the day and
year first written above.


UNITED DENTAL CARE OF ARIZONA, INC.       ASSOCIATED DENTAL CARE PROVIDERS, P.C.


By         William H. Wilcox               By         Joseph V. Erante
  -----------------------------------        -----------------------------------
Its            Director                    Its           Secretary
   ----------------------------------         ----------------------------------

<PAGE>   15


                                   EXHIBIT A
                                       TO
                               UNITED DENTAL CARE
                                    CONTRACT
                            Effective January 1, 1998

1.    Dental Services to be provided, or arranged for, by Dental Group include
      all those dental services specified in the applicable Dental Service
      Agreements and schedules thereto, as currently in effect, as those
      schedules are applicable to any and all Members who select, or are
      assigned to, Dental Group.

2.    Dental Group will arrange for, but not be required to perform, specialty
      dental services for the Plan's Members. The specialty dental services
      shall include, but not be limited to, difficult endodontic therapy,
      periodontal osseous or soft tissue surgery, difficult oral surgery,
      difficult pediatric dental procedures, orthodontics and any other
      procedure not routinely performed by Dental Group. Such specialty care
      shall not be paid for by Dental Group.

3.    Subject to Section 5.2 of the attached Agreement, Dental Group will remain
      on active status. Notwithstanding Section 5.2, however, between January 1,
      1998 and December 31, 1999, Dental Group shall remain on active status
      until the Standard Capitation (as defined in Paragraph 6, below) exceeds
      $265,000.

4.    The Plan shall pay the Dental Group the following amounts per month for
      each member who selects or is assigned to the Dental Group:

<TABLE>
<CAPTION>
                               Employee     Employee and   Family
                               Only         One Dependent
-----------------------------  -----------  -------------  -----------
<S>                            <C>          <C>            <C>
All Members current and
future covered under an        $8.00*       $12.50*        $17.25*
AHP Plan

All current Members under
plans formally sold by         no change**  no change**    no change**
entities then named U.S.
Dental Plan

All current Members under
plans formally sold by         no change**  no change**    no change**
entities then named National
Dental Health Plan

</TABLE>

*     These capitation rates will be paid to Dental Group for all Members,
      current and future. If employer groups covered under AHP plans as of
      January 21, 1997, are switched to United


<PAGE>   16


      Dental Care, Inc., National Dental Plan, U.S. Dental Plan, or any other
      plan under Plan's control, this capitation rate will be in force. For new
      Members in these employer groups selecting or assigned to Dental Group
      this capitation rate will be in force. As these employer groups renew to
      UDC Arizona Plans, Members will be capitated at the then-prevailing UDC
      capitation rates.

**    "no change" denotes that the currently used capitation will be paid on
      those Members covered under these plans currently. If any additional
      members are accepted under these plans it would be at the AHP capitation
      rate unless mutually agreed to by Plan and Dental Group.


5.    With respect to all patients of Dental Group that as of January 21, 1997
      were Members of UDC Arizona Plans under group agreements existing as of
      that date the capitation rates then in effect between Dental Group and
      Plan (or any subsidiaries of Plan) for such Members shall remain in effect
      until, with respect to each such group agreement, the expiration date of
      the current term thereof. Upon renewal of each such group agreement with
      any of the UDC Arizona Plans set forth on the chart below, the capitation
      rate for Members subject to such group agreement shall be as set forth on
      the chart below for such UDC Arizona Plan.


<TABLE>
<CAPTION>
UDC Arizona Plans                    Per Member Per Month
                                     Capitation Payment
-----------------------------------  --------------------
<S>                                  <C>       
185-A                                $5.00 PMPM

355AZ                                $4.10 PMPM

385AZ                                $3.90 PMPM

555-A                                $4.30 PMPM

555AZ-A                              $4.30 PMPM

555AZ-B                              $4.30 PMPM
</TABLE>

6.    Notwithstanding the foregoing provisions of this Exhibit A or the attached
      Agreement to the contrary:

      A.    The Plan shall pay Dental Group according to the following monthly
            schedule of guaranteed capitation payments:

<PAGE>   17


            1.    For the period beginning January 1, 1998 and ending December
                  31, 1999, Plan shall pay Dental Group the greater of $265,000
                  per month or the Standard Capitation for such month. For
                  purposes of this Agreement, "Standard Capitation" shall mean,
                  for any given month, the sum of the per member per month
                  rates, determined as provided pursuant to the preceding
                  provisions of this Exhibit A or, if greater, pursuant to
                  Plan's then-current applicable provider payment schedules, for
                  all Members assigned to Dental Group's facilities.

            2.    After January 1, 2000, the Plan shall pay Dental Group, per
                  month, the greater of 80% of the monthly premium received by
                  Plan or any of its affiliates for all Members assigned to
                  Dental Group's facilities or the Standard Capitation for such
                  month.

      B.    Plan shall permit Dental Group, at all reasonable times and upon the
            request of Dental Group, to inspect Plan's books and records
            relating to the determination or calculation of payments due or made
            to Dental Group under this Agreement.

7.    Agreements with Competing Plans. Notwithstanding Section 12.4 of the
      attached Agreement, if, during the 24-month period from January 1, 1998
      through December 31, 1999: (a) the Dental Group enters into an agreement
      with either Employers Dental Service, Inc. or United Concordia Companies,
      Inc. (each, a "Competing Company") for the provision of dental care to
      members of plans of such Competing Company ("Competing Plans"); (b) after
      the date of any such agreement, an employer group terminates its Dental
      Service Agreement with the Plan and enters into a dental service agreement
      with a Competing Plan; and (c) any Members belonging to such employer
      group are, at the time of such termination, assigned to any facilities of
      the Dental Group; then, for the remainder of such 24-month period, the
      minimum monthly payment guaranteed to the Dental Group under Section 6A1,
      above, shall be reduced by the amount of the monthly premium in effect
      between the employer group and the Plan at the time of such termination;
      provided that (1) if no Members belonging to such employer group are, at
      the time of such termination, assigned to any facilities of the Dental
      Group, there shall be no such reduction of such minimum monthly payment
      guarantee; and (2) if, after entering into an agreement for the provision
      of dental care with Dental Group, a Competing Company enters into any
      acquisition, merger, consolidation, joint venture, or other business
      combination with any person or entity that is, at that time, a party to a
      dental care provision agreement with Dental Group (an "Acquisition") which
      results in such Competing Company's shareholders immediately before the
      consummation of such Acquisition owning, immediately after the
      consummation of such


<PAGE>   18


      Acquisition, less than 50% of the issued and outstanding capital stock of
      such Competing Company, the provisions of this Paragraph 7 shall no longer
      apply with respect to such Competing Company.

UNITED DENTAL CARE OF ARIZONA, INC.       ASSOCIATED DENTAL CARE PROVIDERS, P.C.


By          William H. Wilcox              By         Joseph V. Errante
  -----------------------------------        -----------------------------------
Its             Director                   Its            Secretary
   ----------------------------------         ----------------------------------