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                                                                   EXHIBIT 10.33



                       FOURTH AMENDMENT TO LOAN DOCUMENTS


THIS FOURTH AMENDMENT TO LOAN DOCUMENTS (this "Amendment"), made as of the 31st
day of December, 1998, is between BIRNER DENTAL MANAGEMENT SERVICES, INC., a
Colorado corporation ("Borrower") and KEYBANK NATIONAL ASSOCIATION, a national
banking association ("Lender").

                                R E C I T A L S:

A.       Lender has made a loan (the "Revolving Loan") to Borrower, which
         Revolving Loan is evidenced and/or secured by (1) a Promissory Note
         (the "Note") dated as of October 31, 1996 in the original principal
         amount of $800,000.00 executed by Borrower and payable to the order of
         Lender, (2) by a Security Agreement (the "Security Agreement") dated as
         of October 31, 1996 from Borrower for the benefit of Lender also
         securing payment of the Note, and (3) by a Credit Agreement (the
         "Credit Agreement") dated as of October 31, 1996 between Borrower and
         Lender, and (4) by certain other documents or instruments (the Note,
         the Security Agreement, the Credit Agreement and such other documents
         and instruments, as same may from time to time be amended or replaced,
         are sometimes collectively referred to herein as the "Loan Documents").
         The Revolving Loan was modified by (i) a Second Amendment to Loan
         Documents dated November 18, 1997 (the "Second Amendment") amending the
         terms and conditions of the Credit Agreement, Security Agreement and
         other Loan Documents to increase the amount of the Revolving Loan to
         $10,000,000, and (ii) by a Third Amendment to Loan Documents dated
         September 30, 1998 (the "Third Amendment").

B.       Borrower and Lender desire to further amend the Credit Agreement,
         Security Agreement, and other Loan Documents under the terms and
         conditions set forth herein.

NOW, THEREFORE, in consideration of the foregoing premises and other good and
valuable consideration, the receipt, adequacy and sufficiency of which are
hereby acknowledged, the parties hereto hereby covenant and agree as follows:

1.       CREDIT AGREEMENT AMENDMENTS. The Credit Agreement is amended as
         follows:

         a.       The amount of the Revolving Loan shall be increased from
                  $10,000,000 to $20,000,000.

         b.       The following definition set forth in Article I of the Credit
                  Agreement shall be revised as follows:

"MATURITY DATE" shall mean February 11, 2001.

         c.       The ratio set forth in Section 6.9 of the Credit Agreement
                  shall be revised to 1.25 to 1.

         d.       The 180 day reference set forth in Section 5.4(a) of the
                  Credit Agreement shall be revised to 120 days.

         e.       Section 6.16 shall be added to Article VI as follows:

         f.       "Section 6.16. Change in Management. Change the management
                  positions of or accept a resignation or other termination,
                  without prior written notification to Lender, of any of the
                  following officers of Borrower: Dennis Genty, Fred Birner or
                  Mark Birner."

         g.       Subsection (z), following subsection (y), shall be added to
                  Section 5.4(d) as follows:

                  "and (z) income statements of the Borrower, showing the
                  financial condition of the Borrower as of the close of such
                  month, certified by one of its Financial Officers as fairly
                  presenting the financial condition of the Borrower."


2.       OTHER LOAN DOCUMENT AMENDMENTS. Each of the other Loan Documents are 
         amended to reflect and to incorporate the amendment to the Credit 
         Agreement as set forth above.




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3.   DOCUMENT RATIFICATION. Except as set forth in Paragraphs 1 and 2 above, all
     of the terms and conditions contained in the Credit Agreement, the Security
     Agreement and other Loan Documents shall remain the same and in full force
     and effect, and are ratified, reaffirmed and republished as of the Closing
     Date.

4.   PAYMENT OF COSTS AND FEES; CONDITIONS PRECEDENT TO DISBURSEMENTS.
     Notwithstanding anything to the contrary set forth herein, in the Note, the
     Credit Agreement, the Security Agreement or the other Loan Documents,
     Lender shall not be required to make any further disbursements of proceeds
     of the Revolving Loan until the following shall have occurred:

     (a)            Borrower shall have paid to Lender an Origination Fee in the
          amount of $25,000 and shall have paid all closing costs and expenses
          of the Lender incurred in connection with this Amendment and all legal
          fees of Lender's counsel relating to this Amendment.

     (b)            Borrower shall have delivered to Lender borrowing 
          resolutions confirming the authority of the individual executing this
          Amendment on behalf of the Borrower.

     (c)            Borrower shall have executed and delivered to Lender the 
          Amended and Restated Promissory Note attached hereto as Exhibit A.

5.   REPRESENTATION OF BORROWER. Borrower hereby confirms that, as of the date
     hereof, (i) Borrower is in compliance with each of the representations,
     warranties and covenants of Borrower set forth in the Loan Documents, (ii)
     no Event of Default exists under the Loan Documents and (iii) no fact or
     condition exists, which with the passage of time and/or giving of notice,
     would constitute an Event of Default under the Loan Documents.

6.   ACKNOWLEDGMENT OF PARTIES. Borrower and Lender acknowledge and agree that
     as of the date hereof, there are no known claims or defaults by either
     party against the other, nor are there any existing covenant violations
     arising from or under the Credit Agreement.

7.   CONTROLLING LAW. The terms and provisions of this Amendment shall be
     construed in accordance with and governed by the laws of the State of
     Colorado.

8.   BINDING EFFECT. This Amendment shall be binding upon and inure to the
     benefit of the parties hereto, their successors and assigns.

9.   CAPTIONS. The paragraph captions utilized herein are in no way intended to
     interpret or limit the terms and conditions hereof, rather, they are
     intended for purposes of convenience only.

10.  COUNTERPARTS. This Amendment may be executed in any number of counterparts,
     each of which shall be effective only upon delivery and thereafter shall be
     deemed an original, and al of which shall be taken to be one and the same
     instrument, for the same effect as if all parties hereto had signed the
     same signature page. Any signature page of this Amendment may be detached
     from any counterpart of this Amendment without impairing the legal effect
     of any signatures thereon and may be attached to another counterpart of
     this Amendment identical in form hereto but having attached to it one or
     more additional signature pages.



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         IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
of the day and year first above written.





                                   LENDER:


                                   KEYBANK NATIONAL ASSOCIATION


                                   By:  /s/Michelle Bushey            
                                      -----------------------------------------
                                        Title: Vice President         


                                   BORROWER:

                                   BIRNER DENTAL MANAGEMENT SERVICES, INC., a
                                   Colorado corporation


                                   By:  /s/Dennis N. Genty            
                                      -----------------------------------------
                                        Title: Chief Financial Officer


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