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                                                                     EXHIBIT 4.2

THE WARRANTS REPRESENTED HEREBY AND THE COMMON STOCK ISSUABLE UPON EXERCISE OF
THE WARRANTS HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR REGISTERED OR QUALIFIED UNDER SECURITIES LAWS
OF ANY STATE OR JURISDICTION AND ARE BEING OFFERED AND SOLD IN RELIANCE UPON
EXEMPTIONS FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND SUCH
LAWS. THE WARRANTS REPRESENTED HEREBY AND THE COMMON STOCK ISSUABLE UPON
EXERCISE OF THE WARRANTS MAY NOT BE OFFERED, SOLD, HYPOTHECATED OR OTHERWISE
TRANSFERRED UNLESS REGISTERED UNDER THE SECURITIES ACT OR AN EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT IS APPLICABLE (IN WHICH CASE THE
ISSUER SHALL HAVE RECEIVED AN OPINION OF COUNSEL IN FORM AND SUBSTANCE
REASONABLY SATISFACTORY TO THE ISSUER TO SUCH EFFECT) AND THE PROVISIONS OF ALL
OTHER APPLICABLE SECURITIES LAWS ARE OBSERVED.

                            BIOLASE TECHNOLOGY, INC.

              Incorporated Under the Laws of the State of Delaware

No._________                                                ________Common Stock
                                                               Purchase Warrants

                          CERTIFICATE FOR COMMON STOCK
                                PURCHASE WARRANTS

        1. Warrant. This Warrant Certificate certifies that:
           -------
______________________________ (the "Registered Holder"), is the registered
owner of the above indicated number of Warrants expiring on the Expiration Date,
as hereinafter defined. One (1) Warrant entitles the Registered Holder to
purchase one (1) share (a "Share") of the common stock, par value $0.001 per
share ("Common Stock"), of BioLase Technology, Inc., a Delaware corporation (the
"Company"), from the Company at a purchase price of __________ Dollars ($______)
(the "Exercise Price") to the extent and on the conditions specified herein at
any time during the Exercise Period, as hereinafter defined, upon surrender of
this Warrant Certificate with the exercise form hereon duly completed and
executed and accompanied by payment of the Exercise Price at the principal
executive office of the Company.

        The Warrants represented by this Warrant Certificate were originally
issued as part of a unit consisting of ten thousand shares of the Company's
Common Stock and five thousand (5,000) Warrants, issued by the Company in a
private placement during 2000.

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         2. Restrictive Legends. Each Warrant Certificate shall bear a legend
            -------------------
substantially in the form of the legend that appears at the beginning of this
Warrant Certificate. Each certificate representing Shares issued upon exercise
of Warrants, unless such Shares are then registered for issuance under the
Securities Act of 1933, as amended (the "Act"), shall bear a legend in
substantially the following form:

         THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
         REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
         "ACT") OR REGISTERED OR QUALIFIED UNDER THE SECURITIES LAWS
         OF ANY STATE OR OTHER JURISDICTION IN RELIANCE UPON
         EXEMPTIONS AFFORDED UNDER THE ACT AND APPLICABLE LAWS OF
         OTHER JURISDICTIONS. THE SHARES REPRESENTED HEREBY MAY NOT BE
         OFFERED, SOLD, HYPOTHECATED OR OTHERWISE TRANSFERRED UNLESS
         REGISTERED UNDER THE ACT OR AN EXEMPTION FROM THE ACT'S
         REGISTRATION REQUIREMENTS IS APPLICABLE (IN WHICH CASE THE
         ISSUER SHALL HAVE RECEIVED AN OPINION OF COUNSEL, IN FORM AND
         SUBSTANCE REASONABLY SATISFACTORY TO THE ISSUER, TO SUCH
         EFFECT) AND ALL OTHER APPLICABLE SECURITIES LAWS ARE
         OBSERVED.

         3. Exercise. Subject to the terms hereof, the Warrants evidenced by
            --------
this Warrant Certificate may be exercised at the Exercise Price in whole or in
part at any time during the period (the "Exercise Period") commencing with the
issuance of the Warrants evidenced hereby and terminating at the close of
business at the location of the principal executive offices of the Company on
_________________ (the "Expiration Date"). The Exercise Period may also be
extended by the Company's Board of Directors.

         A Warrant shall be deemed to have been exercised immediately prior to
the close of business on the date (the "Exercise Date") of the surrender to the
Company during the Exercise Period at its principal executive offices of this
Warrant Certificate with the exercise form attached hereto duly completed and
executed by the Registered Holder and accompanied by payment to the Company, in
cash or by official bank or certified check, of an amount equal to the aggregate
Exercise Price for the Shares being acquired through exercise of Warrants, in
lawful money of the United States of America.

         The person entitled to receive the Shares issuable upon exercise of a
Warrant or Warrants ("Warrant Shares") shall be treated for all purposes as the
holder of such Warrant Shares as of the close of business on the Exercise Date.
The Company shall not issue any fractional share interests in Warrant Shares
issuable or deliverable on the exercise of any Warrant, but the Company will
instead pay a cash adjustment in respect of any fraction of a Warrant Share
which would otherwise be issuable in an amount equal to the same fraction of the
market price of a Share on the date of

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exercise, such market price to be determined in good faith by the Board of
Directors of the Company. If Warrants represented by more than one Warrant
Certificate shall be exercised at one time by the same Registered Holder, the
number of full Shares which shall be issuable on exercise thereof shall be
computed on the basis of the aggregate number of full shares issuable on such
exercise.

         Promptly, and in any event within ten business days after the Exercise
Date, the Company shall cause to be issued and delivered to the person or
persons entitled to receive the same a certificate or certificates for the
number of Warrant Shares deliverable on such exercise.

         The Company may deem and treat the Registered Holder of the Warrants at
any time as the absolute owner thereof for all purposes, and the Company shall
not be affected by any notice to the contrary. The Warrants shall not entitle
the Registered Holder thereof to any of the rights of shareholders or to any
dividend declared on the Shares unless the Registered Holder shall have
exercised the Warrants and thereby purchased the Warrant Shares prior to the
record date for the determination of holders of Shares entitled to such dividend
or other right.

         4. Reservation of Shares and Payment of Taxes. The Company covenants
            ------------------------------------------
that it will at all times reserve and have available from its authorized Common
Stock such number of shares as shall then be issuable on the exercise of
outstanding Warrants. The Company covenants that all Warrant Shares which shall
be so issuable shall be duly and validly issued, fully paid and non-assessable,
and free from all taxes, liens and charges with respect to the issue thereof.

         The Registered Holder shall pay all documentary, stamp or similar taxes
and other government charges that may be imposed with respect to the issuance,
transfer or delivery of any Warrant Shares on exercise of the Warrants. In the
event the Warrant Shares are to be delivered in a name other than the name of
the Registered Holder of the Warrant Certificate, no such delivery shall be made
unless the person requesting the same has paid the amount of any such taxes or
charges incident thereto.

         5. Registration of Transfer. The Warrants represented by this Warrant
            ------------------------
Certificate may be transferred only if such transfer complies with all
applicable federal and state securities laws and, if requested by the Company,
the Registered Holder delivers to the Company an opinion of counsel to that
effect, in form and substance reasonably acceptable to the Company. Certificates
for Warrants to be transferred shall be surrendered to the Company at its
principal executive office. The Company shall execute, issue and deliver in
exchange therefor the Warrant Certificate or Certificates which the Registered
Holder making the transfer shall be entitled to receive. The Company shall keep
transfer books at its principal executive office or at such other office as it
may designate, which shall register Warrant Certificates and the transfer

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thereof. On due presentment at such office of any Warrant Certificate for
registration of a transfer permitted hereunder, the Company shall execute, issue
and deliver to the transferee a new Warrant Certificate representing an equal
aggregate number of Warrants. All Warrant Certificates presented for
registration of transfer or exercise shall be duly endorsed or be accompanied by
a written instrument or instruments of transfer in form satisfactory to the
Company and shall be accompanied by documentary evidence, reasonably
satisfactory to the Company, demonstrating the entitlement of the transferee to
the requested transfer. The Company may require payment of a sum sufficient to
cover any tax or other government charge that may be imposed in connection
therewith.

         All Warrant Certificates so surrendered, or surrendered for exercise,
or for exchange in case of mutilated Warrant Certificates, shall be promptly
canceled by the Company and thereafter retained by the Company until the
Expiration Date. Prior to due presentment for registration of transfer thereof,
the Company may treat the Registered Holder of any Warrant Certificate as the
absolute owner thereof (notwithstanding any notations of ownership or writing
thereon made by anyone other than the Company), and the Company shall not be
affected by any notice to the contrary.

         6. Loss or Mutilation. On receipt by the Company of evidence
            ------------------
satisfactory as to the ownership of and the loss, theft, destruction or
mutilation of this Warrant Certificate, the Company shall execute and deliver,
in lieu thereof, a new Warrant Certificate representing an equal aggregate
number of Warrants. In the case of loss, theft or destruction of any Warrant
Certificate, the individual requesting issuance of a new Warrant Certificate
shall be required to indemnify the Company in an amount satisfactory to the
Company. In the event a Warrant Certificate is mutilated, such Certificate shall
be surrendered and canceled by the Company prior to delivery of a new Warrant
Certificate. Applicants for a new Warrant Certificate shall also comply with
such other reasonable regulations as the Company may prescribe.

         7. Call Option. So long as the average between the high and low prices
            -----------
at which Shares trade on the principal exchange on which, or in the principal
market in which, the Shares then trade (or if the Shares do not trade on a
relevant day, the highest closing bid price on such day) exceeds for the ten
(20) consecutive trading days immediately preceding but not including the date
of such call an amount per Share equal to two hundred percent (200%) of the
Exercise Price, the Company shall have the right and option, upon no less than
thirty (30) days' written notice to the Registered Holder, to call and
thereafter to redeem and acquire all of the Warrants evidenced hereby which
remain outstanding and unexercised at the date fixed for such redemption in such
notice (the "Redemption Date"), which Redemption Date shall be at least 30 days
after the date of such notice, for an amount equal to One Cent ($.01) per
Warrant; provided, however, that the Registered Holder shall be entitled during
the period between the date of such notice and the Redemption Date to exercise
the

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Warrants in accordance with the provisions of Section 3 hereof. Said notice of
redemption shall require the Registered Holder to surrender to the Company, on
the Redemption Date, at the principal executive offices of the Company, the
certificate or certificates representing the Warrants to be redeemed.
Notwithstanding the fact that any Warrants called for redemption have not been
surrendered for redemption and cancellation on the Redemption Date, after the
Redemption Date such Warrants shall be deemed to be expired and all rights of
the Registered Holder of such unsurrendered Warrants shall cease and terminate,
other than the right to receive the redemption price of $.01 per Warrant for
such Warrants, without interest.

         In connection with any call hereunder, the Company shall have no
obligation to call any other stock purchase warrant or warrants, whether or not
having similar terms, and no call made pursuant to any other stock purchase
warrant shall obligate the Company to exercise its right and option to make a
call hereunder, except that the Company shall not call any redeemable stock
purchase warrants expiring ______________ (including the Warrants evidenced
hereby) having terms substantially identical to the Warrants evidenced hereby
unless the Company concurrently calls all such Warrants.

         8. Adjustment of Shares. The number and kind of securities issuable
            --------------------
upon exercise of a Warrant hereunder shall be subject to adjustment from time to
time upon the happening of certain events ("Adjustment Event"), as follows:

                  (a) If the Company shall, at any time prior to the complete
         exercise of the Warrants evidenced hereby, declare or pay to the
         holders of its outstanding Shares, a dividend payable in any kind of
         shares of stock or other securities of the Company, or in property, or
         otherwise than in cash, the Registered Holder when thereafter
         exercising the Warrants evidenced hereby as herein provided shall be
         entitled to receive for the Exercise Price, in addition to one Warrant
         Share, such additional share or shares of stock or scrip representing
         fractions of a share or other securities or property as the Registered
         Holder would have received in the form of such dividend if he had been
         the holder of record of such Warrant Share on the record date for the
         determination of the holders of Shares entitled to receive such
         dividend.

                  (b) If the Company shall, while any Warrants evidenced hereby
         remain in force, effect a stock split, reverse stock split or other
         recapitalization of such character that the Shares for which the
         Warrants are exercisable shall be changed into or become exchangeable
         for a larger or smaller number of Shares, then thereafter the number of
         Shares which the Registered Holder shall be entitled to purchase
         hereunder shall be increased or decreased, as the case may be, in
         direct proportion to the increase or decrease in the number of
         outstanding Shares of the Company arising solely by reason of such
         recapitalization, and the Exercise Price (per Share) shall in the case
         of an increase in the number of Shares be proportionately reduced, and
         in the case of

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     a decrease in the number of shares be proportionately increased, so that
     the aggregate exercise price shall remain the same.

            (c)    In case of any reorganization of the Company (or any other
     corporation the stock or other securities of which are at the time
     receivable upon exercise of a Warrant) or in case the Company (or any such
     other corporation) shall merge into or with or consolidate with another
     corporation or convey all or substantially all of its assets to another
     corporation or enter into a business combination of any form as a result of
     which the Shares or other securities receivable upon exercise of a Warrant
     are converted into other stock or securities of the same or another
     corporation, then and in each such case, the Registered Holder of a
     Warrant, upon exercise of the purchase right at any time after the
     consummation of such reorganization, consolidation, merger, conveyance or
     combination, shall be entitled to receive, in lieu of the Shares or other
     securities to which such Registered Holder would have been entitled had he
     exercised the purchase right immediately prior thereto, such stock and
     securities which such Registered Holder would have owned immediately after
     such event with respect to the Shares and other securities for which a
     Warrant may have been exercised immediately before such event had the
     Registered Holder exercised the Warrant immediately prior to such event.

            (d)    In case the Company shall at any time prior to the exercise
     of a Warrant evidenced hereby make any distribution of its assets to
     holders of its Shares by liquidating or partial liquidating dividend or by
     way of return of capital, or other than as a dividend payable out of
     earnings or any surplus legally available for dividends under the laws of
     the state of its incorporation, then the Registered Holder when thereafter
     exercising such Warrant as herein provided after the date of record for the
     determination of those holders of Shares entitled to such distribution of
     assets, shall be entitled to receive for the Exercise Price, in addition to
     a Warrant Share, the amount of such assets (or at the option of the
     Company, a sum equal to the value thereof at the time of such distribution
     to holders of Shares as such value is determined by the Board of Directors
     of the Company in good faith) which would have been payable to the
     Registered Holder had such Registered Holder been the holder of record of
     such Warrant Share receivable upon exercise of such Warrant on the record
     date for the determination of those entitled to such distribution.

     In each case of an adjustment in the Shares or other securities receivable
upon the exercise of a Warrant, the Company shall promptly notify the Registered
Holder of such adjustment. Such notice shall set forth the facts upon which such
adjustment is based.

     9.     Reduction in Exercise Price at Company's Option. The Company's Board
            -----------------------------------------------
of Directors may, at its sole discretion, reduce the Exercise Price of the
Warrants in

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effect at any time either for the life of the Warrants or any shorter period of
time determined by the Company's Board of Directors. The Company shall promptly
notify the Registered Holders of any such reduction in the Exercise Price.

     10.    Notices. All notices, demands, elections, or requests (however
            -------
characterized or described) required or authorized hereunder shall be deemed
given sufficiently if in writing and sent by registered or certified mail,
return receipt requested and postage prepaid, or by facsimile or telegram to the
Company, at its principal executive office, and to the Registered Holder, at the
address of such holder as set forth on the books maintained by the Company.

     11.    General Provisions.  This Warrant Certificate shall be construed and
            ------------------
enforced in accordance with, and governed by, the laws of the State of
California. Except as otherwise expressly stated herein, time is of the essence
in performing hereunder. The headings of this Warrant Certificate are for
convenience in reference only and shall not affect the meaning hereof.

     IN WITNESS WHEREOF, the Company has caused this Warrant Certificate to be
duly executed as of the ________ day of ________________.

                                           BioLase Technology, Inc.

                                           By____________________________

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                            BIOLASE TECHNOLOGY, INC.

         The following abbreviations, when used in the inscription on the face
of this instrument, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM - as tenants in common
TEN ENT - as tenants by the entireties
JR TEN - as joint tenants with right of survivorship and not as tenants in
         common
CUST UNIF GIFT MIN ACT - Custodian under Uniform Gift to Minors Act

Additional abbreviations may also be used though not in the above list.

                               FORM OF ASSIGNMENT

            (To be Executed by the Registered Holder if He Desires to
          Assign Warrants Evidenced by the Within Warrant Certificate)

          FOR VALUE RECEIVED ____________________________________________ hereby
sells, assigns and transfers unto ________________________________________
________________________________ (_______) Warrants, evidenced by the within
Warrant Certificate, and does hereby irrevocably constitute and appoint
___________________ __________________ Attorney to transfer the said Warrants
evidenced by the within Warrant Certificates on the books of the Company, with
full power of substitution.

Dated:____________________                _____________________________
                                               Signature

Notice:   The above signature must correspond with the name as written upon the
          face of the Warrant Certificate in every particular, without
          alteration or enlargement or any change whatsoever.

Signature Guaranteed:  ________________________________________________

SIGNATURE MUST BE GUARANTEED BY AN "ELIGIBLE GUARANTOR INSTITUTION", AS DEFINED
IN RULE 17Ad-15 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

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                          FORM OF ELECTION TO PURCHASE
               (To be Executed by the Holder to Exercise Warrants)

To BioLase Technology, Inc.:

         The undersigned hereby irrevocably elects to exercise _________________
_______________________ (______) Warrants evidenced by the within Warrant
Certificate for, and to purchase thereunder, ________________________ (______)
full shares of Common Stock issuable upon exercise of said Warrants and delivery
of $___________ and any applicable taxes.

         The undersigned hereby:

(i) either [check one]

         [_]   certifies that the undersigned is an accredited investor, as
               defined in Rule 501 under the Securities Exchange Act of 1934, as
               amended, and will be the record and beneficial owner of the
               shares of Common Stock to be issued upon exercise of these
               Warrants; or

         [_]   is supplying an opinion of counsel for the undersigned, which
               shall be reasonably satisfactory in form and substance to BioLase
               Technology, Inc., to the effect that the issuance of shares of
               Common Stock pursuant to this exercise is exempt from the
               registration requirements of the Securities Act of 1933, as
               amended; and

(ii) agrees that the undersigned will not offer, sell, hypothecate or otherwise
transfer such shares of Common Stock unless such shares are registered under
said Securities Act or an exemption from the registration requirements of such
Act is applicable (in which case the undersigned shall supply an opinion of
counsel in form and substance reasonably satisfactory to BioLase Technology,
Inc. to such effect) and the provisions of all other applicable securities laws
are observed.

         Please register the certificates for such shares as follows:

                                                     Taxpayer identification or
                                                     social security number:

         ____________________________________  _________________________________
         (Please print name)
________________________________________________________________________________
                             (Please print address)
________________________________________________________________________________

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           (FORM OF ELECTION TO PURCHASE CONTINUES ON FOLLOWING PAGE)

             If said number of Warrants shall not be all the Warrants evidenced
by the within Warrant Certificate, the undersigned requests that a new Warrant
Certificate evidencing the Warrants not so exercised be registered in the name
of the undersigned at the following address and delivered to that address:

________________________________________________________________________________
                                    (Please print address)
________________________________________________________________________________

________________________________________________________________________________

Dated: _______________________    Signature:______________________________

NOTICE:           The above signature must correspond with the name as written
                  upon the face of the within Warrant Certificate in every
                  particular, without alteration or enlargement or any change
                  whatsoever. If the certificate representing the shares is to
                  be registered in a name other than that in which the within
                  Warrant Certificate is registered, the signature of the holder
                  hereof must be guaranteed.

Signature Guaranteed:  ___________________________________________________

SIGNATURE MUST BE GUARANTEED BY AN "ELIGIBLE GUARANTOR INSTITUTION", AS DEFINED
IN RULE 17Ad-15 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

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