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                             SECURED PROMISSORY NOTE

$5,000,000                                              El Segundo, California
                                                           Date: June 15, 2000

         FOR VALUE RECEIVED, the undersigned, Steven R. Matzkin, (the
"BORROWER") promises to pay to the order of Gentle Dental Management, Inc., a
Delaware corporation (the "COMPANY"), the principal sum of Five Million Dollars
($5,000,000), with interest from the date hereof on the unpaid principal at the
rate of ten point two percent (10.2%), compounded annually. The entire unpaid
balance of principal and interest shall be payable on June 15, 2004. All amounts
payable under this promissory note (this "NOTE") shall be payable in lawful
money of the United States of America. The performance of Borrower's obligations
hereunder are secured by that certain Pledge and Security Agreement (the "Pledge
Agreement") of even date herewith by and between the Company and Borrower.

         The principal and accrued interest due under this Note will be with
full recourse to the Borrower only until June 15, 2002, at which time the loan
and accrued interest will be with recourse only to the Collateral (as defined in
the Pledge Agreement).

         The Borrower at his option may prepay this Note in whole or in part
without penalty at any time or from time to time prior to the due date for
full payment, on ten (10) days' prior written notice to the Company. Any such
prepayments shall be applied first to accrued and unpaid interest and then to
principal on this Note. The Borrower may prepay this Note in cash or through
the exchange of Company Common Stock (based on the fair market value of
InterDent, Inc. Common Stock, which shall equal the average of the last
available market closing price of the ten (10) most recent trading days prior
to the written notice if the Company is publicly traded, or based on the good
faith determination of the InterDent, Inc. Board of Directors if the Company
is not publicly traded; provided, however, that after June 15, 2002, the
value of the Common Stock exchanged ("Exchange Value") shall be the greater
of the fair market value as determined above or $6.125 per share; and,
provided further that after June 15, 2002 if the Employee remains employed by
the Company and the Note or any portion remains outstanding, the Company
shall return to the Employee any Collateral in excess of the amount needed to
secure the principle amount of the Loan, valuing the Common Stock at its
Exchange Value as described above. In the event that the current fair market
value of the shares, as determined above, exceeds $6.125, additional
Collateral will be retained by the Company to secure the accrued interest to
that date.

         If Borrower voluntarily terminates employment his relationship with
InterDent, Inc. or is terminated for cause, the entire unpaid balance of
principal and accrued interest under this instrument shall become immediately
payable. If payment is not made when due such failure to pay shall constitute
an Event of Default. After an Event of Default, if suit is commenced to
collect this Note or any portion hereof, or to effect the collection of any
judgment for failure to make payment hereunder when and as due, such
attorneys' fees and costs as the court may deem reasonable shall be added to
the principal amount

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of this Note. The Borrower hereby waives presentment for payment, protest,
notice of protest and notice of non-payment of this Note.

         This Note shall be governed by, and construed and enforced in
accordance with the laws of the State of California, without regard to conflicts
of laws principles.

         Any provision of this Note may be amended, waived or modified upon the
written consent of each of the Borrower and the Company.

         IN WITNESS WHEREOF, the undersigned has signed, dated and delivered
this note as of the date and year first above written.

                                       BORROWER:

                                       /s/ Steven R. Matzkin
                                       --------------------------------
                                       Name:   Steven R. Matzkin D.D.S.
                                            ---------------------------

Acknowledged:

INTERDENT, INC.

/s/ Michael T. Fiore
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Michael T. Fiore
Co-Chairman and Chief Executive Officer