AMENDMENT AGREEMENT NO. 6 AND WAIVER

AMENDMENT AGREEMENT NO. 6 AND WAIVER, effective as of April 13, 2001 (this "Amendment"), to the AMENDED
AND RESTATED CREDIT AGREEMENT, dated as of June 15, 1999 (as heretofore amended and as may be further amended, modified or supplemented from time to time the "Credit
Agreement"), among GENTLE DENTAL SERVICE CORPORATION, a Washington corporation ("Dental Service"), GENTLE DENTAL
MANAGEMENT, INC., a Delaware corporation ("Dental Management") and DENTAL CARE ALLIANCE, INC., a Delaware corporation
("DCA"; DCA, Dental Service and Dental Management, each a "Borrower" and collectively, the
"Borrowers"), the Guarantors named therein, the financial institutions from time to time party thereto (collectively, the
"Lenders"), UNION BANK OF CALIFORNIA, N.A., as administrative agent for the Lenders (in such capacity, the "Administrative
Agent") and THE CHASE MANHATTAN BANK ("Chase"), as syndication agent for the Lenders (in such capacity, the
"Syndication Agent").

WHEREAS,
the Borrowers, the Guarantors and the Lenders desire to amend certain provisions of the Credit Agreement as set forth herein;

WHEREAS,
the Borrowers have requested that the Lenders waive and the Lenders have agreed to waive noncompliance with certain provisions of the Credit Agreement as specified more
particularly herein;

WHEREAS,
the Borrowers have requested that the Lenders consent, and the Lenders have agreed to consent, to (i) the sale of assets of Dental Service and its subsidiary,
DentalCo. Management Services of Maryland, Inc. ("DMSM"), that are used in the operations of the Affiliated Dental Practices known as Mid-Atlantic Dental Associates of Annapolis and
Mid-Atlantic Dental Associates of Cross Keys (the "Annapolis/Cross Keys Practices") to MON Acquisition Corp., pursuant to an Asset Purchase
Agreement dated on or about April 12, 2001 (the "MON Disposition") and (ii) the sale of assets of Dental Management that are used in the
operations of the Affiliated Dental Practice conducted by Burns Dental Corporation under the name Naismith Dental Group to Villanova, LLC., pursuant to an Asset Purchase Agreement dated
April 2001 (the "Villanova Disposition"; the MON Disposition and the Villanova Disposition being herein referred to as the
"Dispositions");

WHEREAS,
in connection with the MON Disposition, Dental Service will enter into an amendment to the Management Agreement for the Annapolis/Cross Keys Practices, which amendment
requires the consent of Required Lenders; and

WHEREAS,
the Borrowers intend to enter into amendments with respect to outstanding Subordinated Indebtedness, which amendments require consent of Requisite Lenders.

NOW,
THEREFORE, the Borrowers, the Guarantors, the Lenders, the Administrative Agent and the Syndication Agent hereby agree as follows:

SECTION
1.CAPITALIZED TERMS.Capitalized terms used herein and not defined shall have the respective
meanings assigned to such terms in the Credit Agreement.

SECTION
2.AMENDMENTS TO THE CREDIT AGREEMENT.Upon the fulfillment of the conditions set forth in
Section 6 hereof, the Credit Agreement is hereby amended as follows:

2.1DEFINITIONS.  A. Section 1.01 of the Credit Agreement is hereby amended by adding the
following definitions:



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B.  Section 1.01
of the Credit Agreement is hereby further amended by deleting the definitions of the terms 'Adjusted Senior Debt', 'Capital Expenditures',
'Change of Control', 'Credit Event', 'Credits', 'Debt Service Expense', 'EBITDA', 'Excess Cash Flow', 'Final Maturity Date', 'Guarantor', 'Interest Margin', 'Interest Payment Date', 'Leverage Ratio',
'Mandatory Prepayment', 'Obligations' and 'Permitted Acquisition', and inserting the following in lieu thereof:



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C.  Section 1.01
of the Credit Agreement is hereby further amended by deleting the definitions of the terms 'Acquisition Basket', 'Acquisition Capital
Expenditures', 'Adjusted EBITDA', 'Adjusted Total Funded Debt', 'DCA Merger', 'De Novo Capital Expenditures', 'De Novo Dental Practice', 'Equity Transaction', 'Excess Proceeds', 'Fixed Charge Coverage
Ratio', 'Interest Leverage Ratio', 'Letter of Credit', 'Letter of Credit Usage', 'Net Worth', 'Permitted De Novo Capital Expenditure', 'Pro Forma Adjusted EBITDA', 'Pro Forma Adjusted Senior Funded
Debt', 'Pro Forma Adjusted Total Funded Debt', 'Pro Forma Cash Interest Expense', 'Pro Forma EBITDA', 'Pro Forma Interest Coverage Ratio', 'Pro Forma Interest Leverage Ratio' and 'Pro Forma Leverage
Ratio'.

2.2THE LOANS.

A.  The
Credit Agreement (including, without limitation, Sections 2.01, 2.06, 2.07, 2.09, 2.10, 2.12, 2.14 and 5.01 of the Credit Agreement) is hereby amended by
deleting the references to Letters of Credit and Letter of Credit Usage and any references to Sections 2.17-2.20 (as in effect prior to the Sixth Amendment Date) appearing therein.

B.  Section 2.03
of the Credit Agreement is hereby amended to read in full as follows:



C.  Section 2.04(c)
of the Credit Agreement is hereby amended to read in full as follows:



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D.  Section 2.07(d)
of the Credit Agreement is hereby amended to read in full as follows:



E.  Section 2.08(a)
of the Credit Agreement is hereby amended to read in full as follows:



F.  Section 2.09(d)
of the Credit Agreement is hereby amended to read in full as follows:



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G.  Section 2.09(e)
of the Credit Agreement is hereby amended to read in full as follows:



H.  Section 2.09(g)
of the Credit Agreement is hereby amended to read in full as follows:



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I.  Section 2.09(j)
of the Credit Agreement is hereby amended to read in full as follows, and Sections 2.09(k) and (l) are hereby deleted:



J.  Sections
2.17 and 2.18 of the Credit Agreement are hereby amended to read in full as follows, and Sections 2.19 and 2.20 of the Credit Agreement are hereby deleted:



2.3REPRESENTATIONS AND WARRANTIES.  A. Section 4.01 of the Credit Agreement is hereby amended to
read in full as follows:



B.  4.14
of the Credit Agreement is hereby amended to read in full as follows:



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C.  Article IV
of the Credit Agreement is further amended by adding the following as Section 4.25:



2.4AFFIRMATIVE COVENANTS.  A. Section 6.05(e) of the Credit Agreement is hereby amended by
deleting the reference to Section 7.11 appearing in clause (i) thereof.

B.  Section 6.05(j)
of the Credit Agreement is hereby amended to read in full as follows:



C.  Section 6.05
of the Credit Agreement is hereby further amended by adding the following as paragraphs (l), (m) and (n) thereof:



D.  Sections
6.19, 6.20 and 6.26 of the Credit Agreement are hereby deleted and Section 6.17 of the Credit Agreement is hereby amended to read in full as
follows:



E.  Section 6.18
of the Credit Agreement is hereby amended to read in full as follows:



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F.  Section 6.21
of the Credit Agreement is hereby amended by adding the following at the beginning thereof:



G.  Section 6.24
of the Credit Agreement is hereby amended by deleting the phrase 'Within 60 days of the Closing Date,' and inserting the following in
lieu thereof:



2.5NEGATIVE COVENANTS.  A. Section 7.04 of the Credit Agreement is hereby amended to read
in full as follows:



B.  Section 7.05
of the Credit Agreement is hereby amended to read in full as follows:



C.  Section 7.06
of the Credit Agreement is hereby amended by deleting paragraph (g) thereof and amending paragraphs (f) and (j) thereof to
read in full as follows:



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D.  Section 7.07 of the Credit Agreement is hereby amended to read in full as follows:



E.  Section 7.08
of the Credit Agreement is hereby amended, effective March 31, 2001, to read in full as follows:



Quarter Ending

Cash FlowMarch 31, 2001

$
4,500,000June 30, 2001


9,100,000September 30, 2001


13,700,000December 31, 2001


18,600,000March 31, 2002


19,700,000June 30, 2002


20,800,000September 30, 2002


21,900,000December 31, 2002


23,000,000March 31, 2003


24,250,000June 30, 2003 and thereafter


25,000,000


F.  Section 7.09
of the Credit Agreement is hereby amended, effective March 31, 2001, to read in full as follows:



Quarter Ending

RatioMarch 31, 2001

3.20:1.00June 30, 2001

3.20:1.00September 30, 2001

3.20:1.00December 31, 2001

3.00:1.00March 31, 2002

2.75:1.00June 30, 2002

2.50:1.00September 30, 2002

2.25:1.00December 31, 2002

1.90:1.00March 31, 2003

1.70:1.00June 30, 2003 and thereafter

1.50:1.00


G.  Section 7.10
of the Credit Agreement is hereby amended, effective March 31, 2001, to read in full as follows:



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Month

Liquidity AmountMarch 31, 2001

$
2,300,000April 30, 2001


2,300,000May 31, 2001


2,300,000June 30, 2001


3,800,000July 31, 2001


3,500,000August 31, 2001


3,200,000September 30, 2001


2,900,000October 31, 2001 and thereafter


2,500,000




H.  Section 7.11
and Section 7.21 of the Credit Agreement are hereby deleted.

I.  Section 7.17(a)
of the Credit Agreement is hereby amended to read in full as follows:



2.6MISCELLANEOUS.

A.  Section 11.01(c)
of the Credit Agreement is hereby amended to read in full as follows:



B.  Section 11.01
of the Credit Agreement is hereby amended by adding the following as subsection (e):



C.  Section 11.04(a)
of the Credit Agreement is hereby amended to read in full as follows:



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D.  SECTION 11.05
of the Credit Agreement is hereby amended to read in full as follows:



E.  SECTION 11.06
of the Credit Agreement is hereby amended to read in full as follows:



F.  Article XIII
of the Credit Agreement is hereby amended to read in full as follows:



G.Exhibit Lto the Credit Agreement (Form of Covenant Compliance Certificates) is hereby amended to read as set
forth inExhibit Lhereto.

SECTION
3.WAIVER AND CONSENT.A. Subject to the terms and conditions set forth herein and in reliance
on the representations and warranties of Borrowers herein contained, the Lenders hereby waive (i) Events of Default arising by reason of defaults existing under the Convertible Subordinated
Notes and the Senior Subordinated Notes to the extent such defaults are waived pursuant to the amendments to the Convertible Subordinated Notes and the Senior Subordinated Note delivered

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pursuant to Section 6.1 and Section 6.5 of this Amendment and (ii) noncompliance by the Borrowers with the provisions of (a) Sections 7.08, 7.09, 7.10 and 7.11, as such
provisions were in effect prior to the Sixth Amendment Date, at September 30, 2000, December 31, 2000 and March 31, 2001, and for the periods then ended and (b) Sections
6.01 and 7.05 resulting from the dissolution of SPDS DMI, Inc., Gentle Dental IF, Inc. and GMS Dental Group Management of Southern California, Inc. and the merger of Serra Park
into Dental Management,providedthat (1) each such dissolution results in the assets (if any) and liabilities (if any) of each dissolving
company being assumed by the dissolving company's immediate parent and (2) the merger of Serra Park results in the assets and liabilities of Serra Park being assumed by Dental Management. Upon
delivery of evidence of completion of a dissolution or merger to the Administrative Agent satisfactory to the Administrative Agent, the dissolving or merged company shall cease to be a "Grantor" under
the Security Agreement and a "Guarantor" under the Credit Agreement and the stock of such subsidiary shall no longer be considered "Pledged Stock" or "Collateral" under the Pledge Agreement.
Notwithstanding the foregoing, the security interest of the Administrative Agent (for the ratable benefit of the Lenders) in the assets of each subsidiary that is dissolved or merged as permitted
hereby shall continue.

B.  Subject
to the terms and conditions set forth herein and in reliance on the representations and warranties of the Borrowers herein contained, the Lenders hereby
consent to (i) the Dispositions,providedthat the Dispositions occur by April 30, 2001 and result in the Borrowers receiving cash
proceeds of not less than $3,000,000 (before deduction of expenses and taxes), an 8% $254,000 Promissory Note due March 2002, and forgiveness of Indebtedness of not less than $696,000, which
Indebtedness is evidenced by a promissory note dated February 24, 1997, (ii) the release of Liens in favor of the Lenders to the extent that such Liens encumber assets sold pursuant to
the Dispositions and (iii) the entering into by Dental Service of an amendment to the Management Agreement with Mid-Atlantic Dental Associates, P.A. that excludes the
Annapolis/Cross Keys Practices from the operation of such agreement;providedthat the cash proceeds of the Dispositions shall be applied as set forth
in Section 2.09 of the Credit Agreement, as amended hereby.

C.  Subject
to the terms and conditions set forth herein and in reliance on the representations and warranties of the Borrowers herein contained, the Lenders hereby
consent to the amendments to the Senior Subordinated Note and the Convertible Subordinated Notes reflected in the amendments delivered pursuant to Sections 6.1, 6.2 and 6.3 hereof and the amendment to
the Senior Subordinated Note requiring an increase of the rate of interest thereon, during such time as interest is not paid in cash, to not more than 161/2% per annum and payment of an
amendment fee in the form of an additional subordinated note having the same terms and conditions as the Senior Subordinated Note in an amount not to exceed $2,250,000; providedthat the payment of
interest is subject to the amendment referred to in Section 6.1 of this Amendment.

SECTION
4.LIMITATION OF WAIVER AND CONSENT.Without limiting the generality of the provisions of
Section 11.08 of the Credit Agreement, the waiver and consent set forth in Section 3 shall be limited precisely as written and are provided solely with respect to (a) the defaults
under the Senior Subordinated Note and the Convertible Subordinated Notes described in Section 3, (b) noncompliance by the Borrowers with Sections 6.01, 7.05, 7.08, 7.09, 7.10 and 7.11,
(c) the Dispositions and the release of Liens on related Collateral as specified in Section 3 and (d) the amendments to the Senior Subordinated Note and the Convertible
Subordinated Notes described in Section 3. Nothing in this Amendment shall be deemed to constitute (i) a waiver of any other defaults under the Senior Subordinated Note and the
Convertible Subordinated Notes or of compliance by Borrowers with respect to Sections 6.01, 7.05, 7.08, 7.09, 7.10 and 7.11 of the Credit Agreement in any other instance, (ii) a consent to any
sale or disposition of assets or release of Collateral other than the Dispositions and release of Liens on Collateral as specified in Section 3, (iii) a consent to any amendment of any
Subordinated Indebtedness other than as specified in Section 3 or (iv) a waiver of

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or consent to noncompliance with any other term, provision or condition of the Credit Agreement or any other instrument or agreement referred to therein.

SECTION
5.ADDITIONAL COMPANIES.By each company's signature below, DentalCo Management Services of
Maryland, Inc. and The Dental Center, Inc. (each an "Additional Company") shall each become a party to and be bound by the provisions of
the Credit Agreement as a Guarantor and shall have the rights and obligations of a Guarantor hereunder, thereunder and under the other Loan Documents.

SECTION
6.CONDITIONS PRECEDENT.This Amendment shall become effective upon the execution and delivery
of counterparts hereof by the Borrowers, the Guarantors, the Lenders and each of the Agents to the Administrative Agent and the fulfillment of the following conditions:



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SECTION
7.CONFIRMATION OF LOAN DOCUMENTS.Each Loan Party, by its execution and delivery of this
Amendment, irrevocably and unconditionally ratifies and confirms in favor of the Administrative Agent that it consents to the terms and conditions of the Credit Agreement as it has been amended by
this Amendment and that notwithstanding this Amendment, each Loan Document to which such Loan Party is a party shall continue in full force and effect in accordance with its terms, as

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it has been amended on the date hereof, and is and shall continue to be applicable to all of the Obligations.

SECTION
8.MISCELLANEOUS.



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IN WITNESS WHEREOF, the Borrowers, Guarantors, the Administrative Agent, the Syndication Agent and the Required Lenders have caused this Amendment to be duly executed by their
respective authorized officers as of the day and year first above written.

| |  | GENTLE DENTAL SERVICE CORPORATION,as a Borrower                        
| |  | -----------------------------------------------------------------------
| |  | By:                                                                    
| |  | Name: Michael T. Fiore
Title: President                                
| |  | GENTLE DENTAL MANAGEMENT, INC.,as a Borrower                           
| |  | By:                                                                    
| |  | Name: Michael T. Fiore
Title: President                                
| |  | DENTAL CARE ALLIANCE, INC.,as a Borrower                               
| |  | By:                                                                    
| |  | Name: Steven R. Matzkin
Title: President                               
| |  | GMS DENTAL GROUP MANAGEMENT OF HAWAII, INC.,as a Guarantor             
| |  | By:                                                                    
| |  | Name: Michael T. Fiore
Title: President                                
| |  | GMS DENTAL GROUP MANAGEMENT OF SOUTHERN CALIFORNIA, INC.,as a Guarantor
| |  | By:                                                                    
| |  | Name: Michael T. Fiore
Title: President                                

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| |  | GENTLE DENTAL OF IRVINE,as a Guarantor               
| |  | -----------------------------------------------------
| |  | By:                                                  
| |  | Name: Michael T. Fiore
Title: President              
| |  | GDSC OF PIEDMONT, INC.,as a Guarantor                
| |  | By:                                                  
| |  | Name: Michael T. Fiore
Title: President              
| |  | GENTLE DENTAL LEGACY, INC.,as a Guarantor            
| |  | By:                                                  
| |  | Name: Michael T. Fiore
Title: President              
| |  | DENTAL CARE ALLIANCE OF FLORIDA, INC.,as a Guarantor 
| |  | By:                                                  
| |  | Name: Steven R. Matzkin
Title: President             
| |  | DENTAL CARE ALLIANCE OF MICHIGAN, INC.,as a Guarantor
| |  | By:                                                  
| |  | Name: Steven R. Matzkin
Title: President             
| |  | DENTAL CARE ALLIANCE OF GEORGIA, INC.,as a Guarantor 
| |  | By:                                                  
| |  | Name: Steven R. Matzkin
Title: President             

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|                                    |  | DENTAL CARE ALLIANCE OF INDIANA, INC.,as a Guarantor         
|----------------------------------- |  | -------------------------------------------------------------
|                                    |  | By:                                                          
|                                    |  | Name: Steven R. Matzkin
Title: President                     
|                                    |  | DENTAL ONE ASSOCIATES, INC.,as a Guarantor                   
|                                    |  | By:                                                          
|                                    |  | Name: Steven R. Matzkin
Title: President                     
|                                    |  | DENTAL CARE ALLIANCE OF PENNSYLVANIA, INC.,as a Guarantor    
|                                    |  | By:                                                          
|                                    |  | Name: Steven R. Matzkin
Title: President                     
|Additional Companies as Guarantors: |  | DENTALCO MANAGEMENT SERVICES OF MARYLAND, INC.,as a Guarantor
|                                    |  | By:                                                          
|                                    |  | Name: Michael T. Fiore
Title: President                      
|                                    |  | THE DENTAL CENTER, INC.,as a Guarantor                       
|                                    |  | By:                                                          
|                                    |  | Name: Michael T. Fiore
Title: President                      

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|Lenders: |  | UNION BANK OF CALIFORNIA, N.A..as Administrative Agent and Lender
|-------- |  | -----------------------------------------------------------------
|         |  | By:                                                              
|         |  | Name: Thomas Fratar
Title: Vice President                        
|         |  | THE CHASE MANHATTAN BANK,as Syndication Agent and as a Lender    
|         |  | By:                                                              
|         |  | Name: Eric Groberg                                               
|         |  |                                                                  
|         |  | Title: Vice President                                            
|         |  |                                                                  
|         |  | U.S. BANK NATIONAL ASSOCIATION,as Lender                         
|         |  | By:                                                              
|         |  | Name: Daniel J. Falstad                                          
|         |  |                                                                  
|         |  | Title: Vice President                                            
|         |  |                                                                  
|         |  | FLEET CAPITAL CORPORATION,as a Lender                            
|         |  | By:                                                              
|         |  | Name: Leslie Reuter                                              
|         |  |                                                                  
|         |  | Title: Sr. Vice President                                        
|         |  |                                                                  

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|                               |  | BANK OF AMERICA, N.A.(successor by merger to NationsBank, N.A.), as a Lender
|------------------------------ |  | ----------------------------------------------------------------------------
|                               |  | By:                                                                         
|                               |  | Name: Ronald J. Parisi                                                      
|                               |  |                                                                             
|                               |  | Title: Sr. Vice President                                                   
|                               |  |                                                                             
|                               |  | FIRST NATIONAL BANK,as a Lender                                             
|                               |  | By:                                                                         
|                               |  | Name: Daniel T. Grency                                                      
|                               |  |                                                                             
|                               |  | Title: CEO                                                                  
|                               |  |                                                                             
|                               |  | CITIZENS BANK OF MASSACHUSETTS,as a Lender                                  
|                               |  | By:                                                                         
|                               |  | Name: Lawrence E. Jacobs                                                    
|                               |  |                                                                             
|                               |  | Title: Vice President                                                       
|                               |  |                                                                             
|                               |  | SOVEREIGN BANK,as a Lender                                                  
|                               |  | By:                                                                         
|                               |  | Name: Roland D. Lamothe                                                     
|                               |  |                                                                             
|                               |  | Title: Vice President                                                       
|                               |  |                                                                             
|Solely as to Sections 7 and 8: |  | INTERDENT, INC.,as a Guarantor                                              
|                               |  | By:                                                                         
|                               |  | Name: Michael T. Fiore                                                      
|                               |  |                                                                             
|                               |  | Title: CEO                                                                  
|                               |  |                                                                             

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Schedule VI

PA UCC Financing Statements and Security Agreements

|Column A                                                                                                                                                                                                                                                               |  | Column B                                                                                                                                                                                                                                                                           
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Burns Dental Corporation
Burrell Dental Corporation
Dental Care Centers of Hawaii
Francis Dental Corporation
Hualalai Dental Services, Inc.
Joseph M. Checchio & Alex J. Gonzales (A Partnership)
Pacific Dental Services Administrative Office
Yep Dental Corporation |  | Bajwa Dental Corporation
Charles Murillo, D.D.S.
Frank Potts, D.D.S., A Dental Corporation
Gerald Aaron, P.C.
Lynda Watanabe, D.D.S., Inc.
Merzenich Dental Corporation
Ned Greenberg, D.D.S. & Associates, P.C.
Schlesinger Dental Corporation
Tej Johl D.D.S., Dental Corporation

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Schedule 2.18

Schedule of Warrants

Lender

Shares of Common StockUnion Bank of California, N.A.

148,515The Chase Manhattan Bank

148,515U.S. Bank National Association

148,515Fleet Capital Corporation

148,515Bank of America, N.A.

148,515First National Bank

59,405Citizens Financial Group, Inc.

99,010Sovereign Bank

99,010


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Schedule 6.05(l)

Form of Cash Flow Reports

(See
Attached)

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