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                            CONFIRMATION OF GUARANTY

                  CONFIRMATION OF GUARANTY dated as of June 15, 1999 by
InterDent, Inc., a Delaware corporation (the "GUARANTOR") in favor of Union
Bank of California, N.A., as agent (in such capacity, the "AGENT") for the
lenders (the "LENDERS") party to the Credit Agreement hereinafter referred to.

                  WHEREAS, Gentle Dental Service Corporation, a Washington
corporation ("GDSC") and Gentle Dental Management, Inc., a Delaware
corporation ("GDM"),the Agent, and the Lenders, are parties to a Credit
Agreement, dated as of September 30, 1998,(the "ORIGINAL CREDIT AGREEMENT");

                  WHEREAS, to guaranty the obligations of GDSC and GDM under
the Original Credit Agreement and under the other Loan Documents delivered in
connection therewith, the Guarantor executed a Guarantee, dated as of March
12, 1999, in favor of the Agent (as amended, supplemented, restated or
otherwise modified from time to time, the "GUARANTEE");

                  WHEREAS, the parties to the Original Credit Agreement are
amending and restating the Original Credit Agreement in its entirety, and
Dental Care Alliance, Inc., a Delaware corporation, ("DCA") is being added as
a borrower (DCA, GDM and GDSC, collectively, the "BORROWERS") pursuant to an
Amended and Restated Credit Agreement dated as of June 15, 1999 among the
Borrowers, the guarantors named therein, the Lenders, The Chase Manhattan
Bank, as syndication agent and the Agent (said agreement, as it may hereafter
be amended, supplemented, restated or otherwise modified from time to time
being the "CREDIT AGREEMENT"; the terms defined therein and not otherwise
defined herein are used herein as therein defined); and

                  WHEREAS, as a condition to the Agent and the Lenders
amending and restating the Original Credit Agreement and to the addition of
DCA as a Borrower, the Lenders have required the execution and delivery of
this Confirmation by the Guarantor.

                  NOW, THEREFORE, it is hereby agreed that:

                  1. The Guarantor hereby irrevocably and unconditionally
confirms in favor of the Agent that it consents to the terms and conditions
of the Credit Agreement and that its Guarantee continues in full force and
effect and is and shall continue to be applicable to all of the Obligations
and to the Credit Agreement.

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                  2. This Confirmation may be executed by the parties hereto
individually or in combination, in one or more counterparts, each of which
shall be an original and all of which shall constitute one and the same
agreement. Delivery of an executed counterpart of a signature page by
telecopier shall be effective as delivery of a manually executed counterpart.

                  3. This Confirmation shall be governed by, and construed in
accordance with, the laws of the State of New York without giving effect to
the conflicts of laws provisions thereof.

                  IN WITNESS WHEREOF, the Guarantor and the Agent have caused
this Confirmation to be duly executed by their respective authorized officers
as of the day and year first above written.

                                       INTERDENT, INC.

                                       By: /s/ Michael T. Fiore
                                           -------------------------------------
                                           Name: Michael T. Fiore
                                           Title: Co-Chairman and
                                                  Chief Executive Officer


                                       UNION BANK OF CALIFORNIA, N.A., as Agent


                                       By: /s/ Nancy A. Perkins
                                           -------------------------------------
                                           Name:  Nancy A. Perkins
                                           Title: Vice President