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                                                                   Exhibit 10.37


                       Guaranty of Fiscal 2002 Shortfall

                               Summary of Terms
                               ----------------

                                (March 4, 2002)



ISSUER:                  BriteSmile, Inc. (the "Company").
                                                -------

FINANCIAL OBLIGATION:    Written commitment (the "Commitment Letter") to the
                                                  -----------------
                         Company's auditor in the form attached hereto as
                         Exhibit A, pursuant to which the undersigned
                         ---------
                         shareholder of the Company agrees under certain
                         circumstances to purchase shares of Company Common
                         Stock (the "Shares") for a portion of the "Shortfall
                                     ------
                         Amount" (i.e. the difference between the Excess Cash
                         Receipts (as defined in the Commitment Letter) and
                         $5,000,000).

CONSIDERATION:           Consideration to the undersigned shareholder shall be
                         for executing the Commitment Letter and for purchasing
                         the Shares, if required to do so, as follows:

                         .    At the time of execution of the Commitment Letter,
                              the Company will issue to each of the undersigned
                              shareholders five year warrants to purchase the
                              restricted Common Stock of the Company at an
                              exercise price of $4.70 per share, in an amount
                              calculated as follows:

                                          The maximum percentage of the
                                          Shortfall Amount to be covered
                              100,000  x  pursuant to the Commitment Letter
                                          ---------------------------------
                                                     $5,000,000

                              For example, if one of the undersigned
                              shareholders agrees to cover 25% of the Shortfall
                              Amount, up to a maximum of $1,250,000, then the
                              Company would issue 25,000 (100,000 x
                              1,250,000/5,000,000) warrants upon signing of the
                              Commitment Letter.
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                         .    If the undersigned shareholders are required to
                              purchase Shares pursuant to the Commitment Letter,
                              the purchase price per Share will be the lesser of
                              (i) $3.76 or (ii) eighty percent (80%) of the
                              closing bid price of the Company's Common Stock as
                              reported by The Nasdaq Stock Market on the date
                              the Company gives notice to the undersigned
                              shareholders that they are required to purchase
                              Shares pursuant to the Commitment Letter.

PIGGYBACK REGISTRATION
RIGHTS:                  The holders of the warrants and the Shares shall be
                         entitled to "piggyback" registration rights on all 1933
                         Act registrations of the Company (except for
                         registrations relating to employee benefit plans and
                         corporate reorganizations), subject, however, to the
                         right of the Company and its underwriters to reduce the
                         number of shares proposed to be registered pro rata in
                         view of market conditions.  Only Common Stock issuable
                         upon exercise of the warrants and Shares issued and
                         outstanding may be registered under the registration
                         rights to be granted in this term sheet.

EXPENSES:                The Company shall bear the registration expenses
                         (exclusive of underwriting discounts and commissions)
                         of all such piggyback registrations.

RESTRICTIONS ON SALE:    The undersigned shareholders will make customary
                         investment representations.


The undersigned shareholders hereby accept the terms set forth above, subject to
the negotiation and execution of definitive agreements.

     Date: March 4, 2002           LCO Investments Limited

                                   By:    /s/ A.M. Pilaro
                                   Its:   Chairman
                                   Commitment: 50% of the Shortfall Amount up
                                          to a maximum of $2,500,000
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     Date: March 2, 2002           John L. Reed


                                   By:    /s/ John L. Reed
                                   Its:   ___________________________________
                                   Commitment: 10% of the Shortfall Amount up
                                          to a maximum of $500,000



     Date: March 4, 2002           Bradford G. Peters

                                   By:    /s/ Bradford G. Peters
                                   Its:   ___________________________________
                                   Commitment: 20% of the Shortfall Amount up
                                          to a maximum of $1,000,000