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                                                                   EXHIBIT 10.49

                                                                       EXHIBIT C

                          REGISTRATION RIGHTS AGREEMENT

            THIS REGISTRATION RIGHTS AGREEMENT, dated as of February 24, 2000,
between the investor or investors signatory hereto (each an "Investor" and
together the "Investors"), and Dental/Medical Diagnostic Systems, Inc. a
Delaware corporation (the "Company").

            WHEREAS, simultaneously with the execution and delivery of this
Agreement, the Investors are purchasing from the Company, pursuant to an
Exchangeable Preferred Stock and Warrants Purchase Agreement dated the date
hereof (the "Purchase Agreement"), up to Two Million Seven Hundred Fifty
Thousand Dollars ($2,750,000) Stated Value of Exchangeable Preferred Stock and
B-1 Warrants to purchase up to 275,000 shares of Common Stock and B-2 Warrants
to purchase up to 550,000 shares of Common Stock (terms not defined herein shall
have the meanings ascribed to them in the Purchase Agreement); and

            WHEREAS, the Company desires to grant to the Investors the
registration rights set forth herein with respect to the Exchange Shares of
Common Stock issuable upon exchange of or as dividends upon the Exchangeable
Preferred Stock purchased pursuant to the Purchase Agreement and shares of
Common Stock issuable upon exercise of the Warrants (hereinafter referred to as
the "Stock" or "Securities" of the Company).

            NOW, THEREFORE, the parties hereto mutually agree as follows:

            Section 1. Registrable Securities. As used herein the term
"Registrable Security" means the Securities until (i) the Registration Statement
has been declared effective by the Commission, and all Securities have been
disposed of pursuant to the Registration Statement, (ii) all Securities have
been sold under circumstances under which all of the applicable conditions of
Rule 144 (or any similar provision then in force) under the Securities Act
("Rule 144") are met, (iii) all Securities have been otherwise transferred to
holders who may trade such Securities without restriction under the Securities
Act, and the Company has delivered a new certificate or other evidence of
ownership for such Securities not bearing a restrictive legend or (iv) such time
as, in the opinion of counsel to the Company, all Securities may be sold without
any time, volume or manner limitations pursuant to Rule 144(k) (or any similar
provision then in effect) under the Securities Act. The term "Registrable
Securities" means any and/or all of the securities falling within the foregoing
definition of a "Registrable Security." In the event of any merger,
reorganization, consolidation, recapitalization or other change in corporate
structure affecting the Common Stock, such adjustment shall be deemed to be made
in the definition of "Registrable Security" as is appropriate in order to
prevent any dilution or enlargement of the rights granted pursuant to this
Agreement.

            Section 2. Restrictions on Transfer. Each Investor acknowledges and
understands that prior to the registration of the Securities as provided herein,
the Securities are "restricted securities" as defined in Rule 144 promulgated
under the Act. Each Investor understands that no disposition or transfer of the
Securities may be made by Investor in the


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absence of (i) an opinion of counsel to the Investor, in form and substance
reasonably satisfactory to the Company, that such transfer may be made without
registration under the Securities Act or (ii) such registration.

                With a view to making available to the Investors the benefits of
Rule 144 under the Securities Act or any other similar rule or regulation of the
Commission that may at any time permit the Investors to sell securities of the
Company to the public without registration ("Rule 144"), the Company agrees to:

                (a) comply with the provisions of paragraph (c)(1) of Rule 144;
and

                (b) file with the Commission in a timely manner all reports and
other documents required to be filed with the Commission pursuant to Section 13
or 15(d) under the Exchange Act by companies subject to either of such sections,
irrespective of whether the Company is then subject to such reporting
requirements.

                Section 3. Registration Rights With Respect to the Securities.

                (a) The Company agrees that it will prepare and file with the
Securities and Exchange Commission ("Commission"), within forty-five (45) days
after the Closing Date a registration statement (on Form S-3, or other
appropriate registration statement form) under the Securities Act (the
"Registration Statement"), at the sole expense of the Company (except as
provided in Section 3(c) hereof), in respect of the Investors, so as to permit a
public offering and resale of the Securities under the Act by the Investors as
selling stockholders and not as underwriters.

                The Company shall use its best efforts to cause such
Registration Statement to become effective within ninety (90) days from the
Closing Date (or 120 days from the Closing Date if the SEC makes a "full review"
of the Registration Statement) or, if earlier, within five (5) days of SEC
clearance to request acceleration of effectiveness. The number of shares
designated in the Registration Statement to be registered shall include the
Warrant Shares, at least 175% of the number of shares issuable upon exchange of
the Exchangeable Preferred Stock assuming exchange in full on the day prior to
filing date of the Registration Statement, and such number of shares as the
Company deems prudent for the purpose of issuing shares of Common Stock as
dividends on the Exchangeable Preferred Stock, and shall include appropriate
language regarding reliance upon Rule 416 to the extent permitted by the
Commission. The Company will notify the Investors of the effectiveness of the
Registration Statement within one Trading Day of such event. In the event that
the number of shares so registered shall be less than 125% of the number of
shares of Registrable Securities remaining unsold (using the Exchange Price of
the Exchangeable Preferred Stock from time to time), or if the SEC does not
permit the registration of the Exchange Shares issuable upon exchange of the
Optional Exchangeable Preferred Stock in the initial Registration Statement,
then the Company shall be obligated to file, within thirty (30) days of such
event (in the case of insufficient shares) or within 30 days of demand by any
Investor who purchases Optional Exchangeable Preferred Stock, a further
Registration Statement registering such remaining shares and shall use its best
efforts to cause

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such additional Registration Statement to become effective within ninety (90)
days of the date of such event.

                (b) The Company will maintain the Registration Statement or
post-effective amendment filed under this Section 3 effective under the
Securities Act until the earlier of (i) the date that none of the Securities
covered by such Registration Statement are or may become issued and outstanding,
(ii) the date that all of the Securities have been sold pursuant to such
Registration Statement, (iii) the date the Investors receive an opinion of
counsel to the Company, which counsel shall be reasonably acceptable to the
Investors, that the Securities may be sold under the provisions of Rule 144
without limitation as to volume, (iv) all Securities have been otherwise
transferred to persons who may trade such shares without restriction under the
Securities Act, and the Company has delivered a new certificate or other
evidence of ownership for such securities not bearing a restrictive legend, or
(v) all Securities may be sold without any time, volume or manner limitations
pursuant to Rule 144(k) or any similar provision then in effect under the
Securities Act in the opinion of counsel to the Company, which counsel shall be
reasonably acceptable to the Investor (the "Effectiveness Period").

                (c) All fees, disbursements and out-of-pocket expenses and costs
incurred by the Company in connection with the preparation and filing of the
Registration Statement under subparagraph 3(a) and in complying with applicable
securities and Blue Sky laws (including, without limitation, all attorneys' fees
of the Company) shall be borne by the Company. The Investors shall bear the cost
of underwriting and/or brokerage discounts, fees and commissions, if any,
applicable to the Securities being registered and the fees and expenses of their
counsel. The Investors and their counsel shall have a reasonable period, not to
exceed five (5) Trading Days, to review the proposed Registration Statement or
any amendment thereto, prior to filing with the Commission, and the Company
shall provide each Investor with copies of any comment letters received from the
Commission with respect thereto within two (2) Trading Days of receipt thereof.
The Company shall qualify any of the Securities for sale in such states as any
Investor reasonably designates and shall furnish indemnification in the manner
provided in Section 6 hereof. However, the Company shall not be required to
qualify in any state which will require an escrow or other restriction relating
to the Company and/or the sellers, or which will require the Company to qualify
to do business in such state or require the Company to file therein any general
consent to service of process. The Company at its expense will supply the
Investors with copies of the applicable Registration Statement and the
prospectus included therein and other related documents in such quantities as
may be reasonably requested by the Investors.

                (d) The Company shall not be required by this Section 3 to
include any Investor's Securities in any Registration Statement which is to be
filed if, in the opinion of counsel to the Company, the proposed offering or
other transfer as to which such registration is requested is exempt from
applicable federal and state securities laws and would result in all purchasers
or transferees obtaining securities which are not "restricted securities", as
defined in Rule 144 under the Securities Act.

                (e) In the event that (i) the Registration Statement to be filed
by the Company pursuant to Section 3(a) above is not filed with the Commission
within forty-five (45)

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days from the Closing Date, (ii) such Registration Statement is not declared
effective by the Commission within the earlier of ninety (90) days from the
Closing Date (or 120 days from the Closing Date if the Commission makes a "full
review" of the Registration Statement) or five (5) days of clearance by the
Commission to request effectiveness, (iii) such Registration Statement is not
maintained as effective by the Company for the period set forth in Section 3(b)
above or (iv) the additional Registration Statement referred to in Section 3(a)
is not filed within thirty (30) days or declared effective within ninety (90)
days as set forth therein (each a "Registration Default") then the Company will
pay Investor (pro rated on a daily basis), as liquidated damages for such
failure and not as a penalty one percent (1%) of the aggregate market value of
shares of Common Stock purchased from the Company (including the Exchange Shares
which would be issuable upon Exchange of the Exchangeable Preferred Stock on any
date of determination, and whether or not the Exchangeable Preferred Stock are
then exchangeable pursuant to their terms) and held by the Investor for each
week until such Registration Statement has been filed, and in the event of late
effectiveness (in case of clause (ii) above) or lapsed effectiveness (in the
case of clause (iii) above), one percent (1%) of the aggregate market value of
shares of Common Stock purchased from the Company and held by the Investor
(including the Exchange Shares which would be issuable upon exchange of the
Exchangeable Preferred Stock on any date of determination, and whether or not
the Exchangeable Preferred Stock are then exchangeable pursuant to their terms)
for each week (regardless of whether one or more such Registration Defaults are
then in existence) until such Registration Statement has been declared
effective. Such payment of the liquidated damages shall be made to the Investors
in cash, within five (5) calendar days of demand, provided, however, that the
payment of such liquidated damages shall not relieve the Company from its
obligations to register the Securities pursuant to this Section. The market
value of the Common Stock for this purpose shall be the closing price (or last
trade, if so reported) on the Principal Market for each day during such
Registration Default. Notwithstanding anything to the contrary contained herein,
a failure to obtain or maintain the effectiveness of a filed Registration
Statement or the ability of an Investor to use an otherwise effective
Registration Statement to effect resales of Securities during the period after
45 days and within 90 days from the end of the Company's fiscal year resulting
solely from the need to update the Company's financial statements contained or
incorporated by reference in such Registration Statement shall not constitute a
Registration Default and shall not trigger the accrual of liquidated damages
hereunder.

                If the Company does not remit the payment to the Investors as
set forth above, the Company will pay the Investors reasonable costs of
collection, including attorneys' fees, in addition to the liquidated damages.
The registration of the Securities pursuant to this provision shall not affect
or limit the Investors' other rights or remedies as set forth in this Agreement.

                (f) No provision contained herein shall preclude the Company
from selling securities pursuant to any Registration Statement in which it is
required to include Securities pursuant to this Section 3.

                (g) If at any time or from time to time after the effective date
of any Registration Statement, the Company notifies the Investors in writing of
the existence of a Potential Material Event (as defined in Section 3(h) below),
the Investors shall not offer or sell

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any Securities or engage in any other transaction involving or relating to
Securities, from the time of the giving of notice with respect to a Potential
Material Event until the Investors receive written notice from the Company that
such Potential Material Event either has been disclosed to the public or no
longer constitutes a Potential Material Event; provided, however, that the
Company may not so suspend the right to such holders of Securities for more than
thirty (30) days in the aggregate (90 days in the case of an acquisition
requiring the filing of audited financial statements of the acquired business
under Form 8-K) during any twelve month period, during the period the
Registration Statement is required to be in effect, and if such period is
exceeded, such event shall be a Registration Default. If a Potential Material
Event shall occur prior to the date a Registration Statement is required to be
filed, then the Company's obligation to file such Registration Statement shall
be delayed without penalty for not more than twenty (20) days, and such delay or
delays shall not constitute a Registration Default. The Company must, if lawful,
give the Investors notice in writing at least two (2) Trading Days prior to the
first day of the blackout period.

                (h) "Potential Material Event" means any of the following: (a)
the possession by the Company of material information not ripe for disclosure in
a registration statement, as determined in good faith by the Chief Executive
Officer or the Board of Directors of the Company that disclosure of such
information in a Registration Statement would be detrimental to the business and
affairs of the Company; or (b) any material engagement or activity by the
Company which would, in the good faith determination of the Chief Executive
Officer or the Board of Directors of the Company, be adversely affected by
disclosure in a registration statement at such time.

            Section 4. Cooperation with Company. The Investors will cooperate
with the Company in all respects in connection with this Agreement, including
timely supplying all information and confirmations reasonably requested by the
Company or the Commission (which shall include all information regarding the
Investors and proposed manner of sale of the Registrable Securities required to
be disclosed in any Registration Statement) and executing and returning all
documents reasonably requested in connection with the registration and sale of
the Registrable Securities and entering into and performing their obligations
under any underwriting agreement, if the offering is an underwritten offering,
in usual and customary form, with the managing underwriter or underwriters of
such underwritten offering. Nothing in this Agreement shall obligate any
Investor to consent to be named as an underwriter in any Registration Statement.
The obligation of the Company to register the Registrable Securities shall be
absolute and unconditional as to those Securities which the Commission will
permit to be registered without naming the Investors as underwriters. Any delay
or delays caused by the Investors by failure to cooperate as required hereunder
shall not constitute a Registration Default.

            Section 5. Registration Procedures. If and whenever the Company is
required by any of the provisions of this Agreement to effect the registration
of any of the Registrable Securities under the Act, the Company shall (except as
otherwise provided in this Agreement), as expeditiously as possible, subject to
the Investors' assistance and cooperation as reasonably required with respect to
each Registration Statement:

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                (a) (i)prepare and file with the Commission such amendments and
supplements to the Registration Statement and the prospectus used in connection
therewith as may be necessary to keep such Registration Statement effective and
to comply with the provisions of the Act with respect to the sale or other
disposition of all securities covered by such registration statement whenever
the Investors shall desire to sell or otherwise dispose of the same (including
prospectus supplements with respect to the sales of securities from time to time
in connection with a registration statement pursuant to Rule 415 promulgated
under the Act) and (ii) take all lawful action such that each of (A) the
Registration Statement and any amendment thereto does not, when it becomes
effective, contain an untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading and (B) the prospectus forming part of the Registration Statement,
and any amendment or supplement thereto, does not at any time during the
Registration Period include an untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading;

                (b) (i)prior to the filing with the Commission of any
Registration Statement (including any amendments thereto) and the distribution
or delivery of any prospectus (including any supplements thereto), provide draft
copies thereof to the Investors as required by Section 3(c) and reflect in such
documents all such comments as the Investors (and their counsel) reasonably may
propose respecting the Selling Shareholders and Plan of Distribution sections
(or equivalents) and (ii) furnish to each Investor such numbers of copies of a
prospectus including a preliminary prospectus or any amendment or supplement to
any prospectus, as applicable, in conformity with the requirements of the Act,
and such other documents, as such Investor may reasonably request in order to
facilitate the public sale or other disposition of the securities owned by such
Investor;

                (c) register and qualify the Registrable Securities covered by
the Registration Statement under such other securities or blue sky laws of such
jurisdictions as the Investors shall reasonably request (subject to the
limitations set forth in Section 3(c) above), and do any and all other acts and
things which may be necessary or advisable to enable each Investor to consummate
the public sale or other disposition in such jurisdiction of the securities
owned by such Investor;

                (d) list such Registrable Securities on the Principal Market, if
the listing of such Registrable Securities is then permitted under the rules of
such Principal Market;

                (e) notify each Investor at any time when a prospectus relating
thereto covered by the Registration Statement is required to be delivered under
the Act, of the happening of any event of which it has knowledge as a result of
which the prospectus included in the Registration Statement, as then in effect,
includes an untrue statement of a material fact or omits to state a material
fact required to be stated therein or necessary to make the statements therein
not misleading in the light of the circumstances then existing, and the Company
shall use its best efforts to prepare and file a curative amendment under
Section 5(a);

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                (f) as promptly as practicable after becoming aware of such
event, notify each Investor who holds Registrable Securities being sold (or, in
the event of an underwritten offering, the managing underwriters) of the
issuance by the Commission of any stop order or other suspension of the
effectiveness of the Registration Statement at the earliest possible time and
take all lawful action to effect the withdrawal, recession or removal of such
stop order or other suspension;

                (g) cooperate with the Investors to facilitate the timely
preparation and delivery of certificates for the Registrable Securities to be
offered pursuant to the Registration Statement and enable such certificates for
the Registrable Securities to be in such denominations or amounts, as the case
may be, as the Investors reasonably may request and registered in such names as
the Investors may request; and, within three (3) Trading Days after a
Registration Statement which includes Registrable Securities is declared
effective by the Commission, deliver and cause legal counsel selected by the
Company to deliver to the transfer agent for the Registrable Securities (with
copies to the Investors) an appropriate instruction and, to the extent
necessary, an opinion of such counsel;

                (h) take all such other lawful actions reasonably necessary to
expedite and facilitate the disposition by the Investors of their Registrable
Securities in accordance with the intended methods therefor provided in the
prospectus which are customary for issuers to perform under the circumstances;

                (i) in the event of an underwritten offering, promptly include
or incorporate in a prospectus supplement or post-effective amendment to the
Registration Statement such information as the managers reasonably agree should
be included therein and to which the Company does not reasonably object and make
all required filings of such prospectus supplement or post-effective amendment
as soon as practicable after it is notified of the matters to be included or
incorporated in such Prospectus supplement or post-effective amendment; and

                      (j) maintain a transfer agent and registrar for its Common
Stock.

            Section 6. Indemnification.

                (a) To the maximum extent permitted by law, the Company agrees
to indemnify and hold harmless the Investors and each person, if any, who
controls an Investor within the meaning of the Securities Act (each a
"Distributing Investor") against any losses, claims, damages or liabilities,
joint or several (which shall, for all purposes of this Agreement, include, but
not be limited to, all reasonable costs of defense and investigation and all
reasonable attorneys' fees and expenses), to which the Distributing Investor may
become subject, under the Securities Act or otherwise, insofar as such losses,
claims, damages or liabilities (or actions in respect thereof) arise out of or
are based upon any untrue statement or alleged untrue statement of any material
fact contained in any Registration Statement, or any related final prospectus or
amendment or supplement thereto, or arise out of or are based upon the omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading; provided,
however, that the Company will not be liable in any such case to the extent, and
only to the extent, that any such loss, claim, damage or liability

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arises out of or is based upon an untrue statement or alleged untrue statement
or omission or alleged omission made in such Registration Statement, preliminary
prospectus, final prospectus or amendment or supplement thereto in reliance
upon, and in conformity with, written information furnished to the Company by
the Distributing Investor, its counsel, affiliates or any underwriter,
specifically for use in the preparation thereof. This indemnity agreement will
be in addition to any liability which the Company may otherwise have.

                (b) To the maximum extent permitted by law, each Distributing
Investor agrees that it will indemnify and hold harmless the Company, and each
officer and director of the Company or person, if any, who controls the Company
within the meaning of the Securities Act, against any losses, claims, damages or
liabilities (which shall, for all purposes of this Agreement, include, but not
be limited to, all reasonable costs of defense and investigation and all
reasonable attorneys' fees and expenses) to which the Company or any such
officer, director or controlling person may become subject under the Securities
Act or otherwise, insofar as such losses, claims, damages or liabilities (or
actions in respect thereof) arise out of or are based upon any untrue statement
or alleged untrue statement of any material fact contained in any Registration
Statement, or any related final prospectus or amendment or supplement thereto,
or arise out of or are based upon the omission or the alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, but in each case only to the extent that such
untrue statement or alleged untrue statement or omission or alleged omission was
made in such Registration Statement, final prospectus or amendment or supplement
thereto in reliance upon, and in conformity with, written information furnished
to the Company by such Distributing Investor, its counsel, affiliates or any
underwriter, specifically for use in the preparation thereof. This indemnity
agreement will be in addition to any liability which the Distributing Investor
may otherwise have.

                (c) Promptly after receipt by an indemnified party under this
Section 6 of notice of the commencement of any action against such indemnified
party, such indemnified party will, if a claim in respect thereof is to be made
against the indemnifying party under this Section 6, notify the indemnifying
party in writing of the commencement thereof; but the omission to so notify the
indemnifying party will not relieve the indemnifying party from any liability
which it may have to any indemnified party except to the extent the failure of
the indemnified party to provide such written notification actually prejudices
the ability of the indemnifying party to defend such action. In case any such
action is brought against any indemnified party, and it notifies the
indemnifying party of the commencement thereof, the indemnifying party will be
entitled to participate in, and, to the extent that it may wish, jointly with
any other indemnifying party similarly notified, assume the defense thereof,
subject to the provisions herein stated and after notice from the indemnifying
party to such indemnified party of its election so to assume the defense
thereof, the indemnifying party will not be liable to such indemnified party
under this Section 6 for any legal or other expenses subsequently incurred by
such indemnified party in connection with the defense thereof other than
reasonable costs of investigation, unless the indemnifying party shall not
pursue the action to its final conclusion. The indemnified parties as a group
shall have the right to employ one separate counsel in any such action and to
participate in the defense thereof, but the fees and expenses of such counsel
shall not be at the expense of the indemnifying party if the indemnifying party
has assumed the defense of the action with counsel reasonably satisfactory to
the indemnified party unless (i) the

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employment of such counsel has been specifically authorized in writing by the
indemnifying party, or (ii) the named parties to any such action (including any
impleaded parties) include both the indemnified party and the indemnifying party
and the indemnified party shall have been advised by its counsel that there may
be one or more legal defenses available to the indemnifying party different from
or in conflict with any legal defenses which may be available to the indemnified
party or any other indemnified party (in which case the indemnifying party shall
not have the right to assume the defense of such action on behalf of such
indemnified party, it being understood, however, that the indemnifying party
shall, in connection with any one such action or separate but substantially
similar or related actions in the same jurisdiction arising out of the same
general allegations or circumstances, be liable only for the reasonable fees and
expenses of one separate firm of attorneys for the indemnified party, which firm
shall be designated in writing by the indemnified party). No settlement of any
action against an indemnified party shall be made without the prior written
consent of the indemnified party, which consent shall not be unreasonably
withheld so long as such settlement includes a full release of claims against
the indemnified party.

            Section 7. Contribution. In order to provide for just and equitable
contribution under the Securities Act in any case in which (i) the indemnified
party makes a claim for indemnification pursuant to Section 6 hereof but is
judicially determined (by the entry of a final judgment or decree by a court of
competent jurisdiction and the expiration of time to appeal or the denial of the
last right of appeal) that such indemnification may not be enforced in such case
notwithstanding the fact that the express provisions of Section 6 hereof provide
for indemnification in such case, or (ii) contribution under the Securities Act
may be required on the part of any indemnified party, then the Company and the
applicable Distributing Investor shall contribute to the aggregate losses,
claims, damages or liabilities to which they may be subject (which shall, for
all purposes of this Agreement, include, but not be limited to, all reasonable
costs of defense and investigation and all reasonable attorneys' fees and
expenses), in either such case (after contribution from others) on the basis of
relative fault as well as any other relevant equitable considerations. The
relative fault shall be determined by reference to, among other things, whether
the untrue or alleged untrue statement of a material fact or the omission or
alleged omission to state a material fact relates to information supplied by the
Company on the one hand or the applicable Distributing Investor on the other
hand, and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission. The Company and
the Distributing Investor agree that it would not be just and equitable if
contribution pursuant to this Section 7 were determined by pro rata allocation
or by any other method of allocation which does not take account of the
equitable considerations referred to in this Section 7. The amount paid or
payable by an indemnified party as a result of the losses, claims, damages or
liabilities (or actions in respect thereof) referred to above in this Section 7
shall be deemed to include any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any such
action or claim. No person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation.

Notwithstanding any other provision of this Section 7, in no event shall any (i)
Investor be required to undertake liability to any person under this Section 7
for any amounts in excess of the

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dollar amount of the proceeds received by such Investor from the sale of such
Investor's Registrable Securities (after deducting any fees, discounts and
commissions applicable thereto) pursuant to any Registration Statement under
which such Registrable Securities are registered under the Securities Act and
(ii) underwriter be required to undertake liability to any person hereunder for
any amounts in excess of the aggregate discount, commission or other
compensation payable to such underwriter with respect to the Registrable
Securities underwritten by it and distributed pursuant to such Registration
Statement.

            Section 8. Notices. All notices, demands, requests, consents,
approvals, and other communications required or permitted hereunder shall be in
writing and, unless otherwise specified herein, shall be (i) hand delivered,
(ii) deposited in the mail, registered or certified, return receipt requested,
postage prepaid, (iii) delivered by reputable air courier service with charges
prepaid, or (iv) transmitted by facsimile, addressed as set forth in the
Purchase Agreement or to such other address as such party shall have specified
most recently by written notice. Any notice or other communication required or
permitted to be given hereunder shall be deemed effective (a) upon hand delivery
or delivery by facsimile, with accurate confirmation generated by the
transmitting facsimile machine, at the address or number designated in the
Purchase Agreement (if delivered on a business day during normal business hours
where such notice is to be received), or the first business day following such
delivery (if delivered other than on a business day during normal business hours
where such notice is to be received) or (b) on the first business day following
the date of sending by reputable courier service, fully prepaid, addressed to
such address, or (c) upon actual receipt of such mailing, if mailed. Either
party hereto may from time to time change its address or facsimile number for
notices under this Section 8 by giving at least ten (10) days' prior written
notice of such changed address or facsimile number to the other party hereto.

            Section 9. Assignment. This Agreement is binding upon and inures to
the benefit of the parties hereto and their respective heirs, successors and
permitted assigns. The rights granted the Investors under this Agreement may be
assigned to any purchaser of substantially all of the Registrable Securities (or
the rights thereto) from an Investor, as otherwise permitted by the Purchase
Agreement.

            Section 10. Additional Covenants of the Company. The Company agrees
that at such time as it otherwise meets the requirements for the use of
Securities Act Registration Statement on Form S-3 for the purpose of registering
the Registrable Securities, it shall file all reports and information required
to be filed by it with the Commission in a timely manner and take all such other
action so as to maintain such eligibility for the use of such form.

            Section 11. Counterparts/Facsimile. This Agreement may be executed
in two or more counterparts, each of which shall constitute an original, but all
of which, when together shall constitute but one and the same instrument, and
shall become effective when one or more counterparts have been signed by each
party hereto and delivered to the other parties. In lieu of the original, a
facsimile transmission or copy of the original shall be as effective and
enforceable as the original.

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            Section 12. Remedies. The remedies provided in this Agreement are
cumulative and not exclusive of any remedies provided by law. If any term,
provision, covenant or restriction of this Agreement is held by a court of
competent jurisdiction to be invalid, illegal, void or unenforceable, the
remainder of the terms, provisions, covenants and restrictions set forth herein
shall remain in full force and effect and shall in no way be affected, impaired
or invalidated, and the parties hereto shall use their best efforts to find and
employ an alternative means to achieve the same or substantially the same result
as that contemplated by such term, provision, covenant or restriction.

            Section 13. Conflicting Agreements. The Company shall not enter into
any agreement with respect to its securities that is inconsistent with the
rights granted to the holders of Registrable Securities in this Agreement or
otherwise prevents the Company from complying with all of its obligations
hereunder.

            Section 14. Headings. The headings in this Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

            Section 15. Governing Law, Arbitration. This Agreement shall be
governed by and construed in accordance with the laws of the State of New York
applicable to contracts made in New York by persons domiciled in New York City
and without regard to its principles of conflicts of laws. Any dispute under
this Agreement shall be submitted to arbitration under the American Arbitration
Association (the "AAA") in New York City, New York, and shall be finally and
conclusively determined by the decision of a board of arbitration consisting of
three (3) members (hereinafter referred to as the "Board of Arbitration")
selected as according to the rules governing the AAA. The Board of Arbitration
shall meet on consecutive business days in New York City, New York, and shall
reach and render a decision in writing (concurred in by a majority of the
members of the Board of Arbitration) with respect to the amount, if any, which
the losing party is required to pay to the other party in respect of a claim
filed. In connection with rendering its decisions, the Board of Arbitration
shall adopt and follow the laws of the State of New York. To the extent
practical, decisions of the Board of Arbitration shall be rendered no more than
thirty (30) calendar days following commencement of proceedings with respect
thereto. The Board of Arbitration shall cause its written decision to be
delivered to all parties involved in the dispute. Any decision made by the Board
of Arbitration (either prior to or after the expiration of such thirty (30)
calendar day period) shall be final, binding and conclusive on the parties to
the dispute, and entitled to be enforced to the fullest extent permitted by law
and entered in any court of competent jurisdiction. The Board of Arbitration
shall be authorized and is hereby directed to enter a default judgment against
any party failing to participate in any proceeding hereunder within the time
periods set forth in the AAA rules. The non-prevailing party to any arbitration
(as determined by the Board of Arbitration) shall pay the expenses of the
prevailing party, including reasonable attorneys' fees, in connection with such
arbitration. Any party shall be entitled to obtain injunctive relief from a
court in any case where such relief is available. The non-prevailing party to
any injunctive proceeding (as determined by the court) shall pay the expenses of
the prevailing party, including reasonable attorney's fees, in connection with
such injunctive proceeding.


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            IN WITNESS WHEREOF, the parties hereto have caused this Registration
Rights Agreement to be duly executed, on the day and year first above written.

                                     DENTAL/MEDICAL DIAGNOSTIC SYSTEMS, INC.


                                     By:  /s/  ROBERT H. GUREVITCH
                                        ----------------------------------------
                                        Robert H. Gurevitch, President

                                     INVESTORS:


                                     AMRO INTERNATIONAL, S.A.


                                     By:________________________________________
                                        H.U. Bachofen, Director


                                     ESQUIRE TRADE & FINANCE INC.


                                     By:________________________________________
                                        Roland Winiger, Authorized Signatory


                                     AUSTINVEST ANSTALT BALZERS


                                     By:________________________________________
                                        Dr. Walter Grill, Authorized Signatory


                                     LEVAL TRADING


                                     By:________________________________________
                                               , Authorized Signatory

                                     THE KESHET FUND, L.P.


                                     By:________________________________________
                                                , Authorized Signatory


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