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                                                                   EXHIBIT 10.35

                        SIXTH AMENDMENT TO LOAN DOCUMENTS


THIS SIXTH AMENDMENT TO LOAN DOCUMENTS (this "Sixth Amendment"), made as of the
20th day of September 1999 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, (ii) by a Third Amendment to Loan Documents
     dated September 30, 1998 (the "Third Amendment"), (iii) by a Fourth
     Amendment to Loan Documents dated December 31, 1998 (the "Fourth
     Amendment") to increase the amount of the Revolving Loan to $20,000,000,
     and (iv) by a Fifth Amendment to Loan Documents dated May 28, 1999 (the
     "Fifth 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 following definition set forth in Article I of the Credit Agreement
shall be revised as follows:

"Borrowing Base" means, through December 31, 1999, three and one-half (3.5)
times the Consolidated EBITDA of the Borrower for the previous twelve (12) month
period. Commencing January 1, 2000 and thereafter for the remaining term of the
Revolving Loan, the Borrowing Base shall mean three (3) times the consolidated
EBITDA of the Borrower for the previous twelve (12) month period.

     b. Section 6.12 of the Credit Agreement shall be amended in its entirety to
read as follows:

6.12 Senior Debt to EBITDA. The ratio of Consolidated Senior Debt to
Consolidated EBITDA shall not be greater than 3.5 to 1.0 through December 31,
1999. Commencing January 1, 2000 and thereafter for the remaining term of the
Revolving Loan, the ratio of Consolidated Senior Debt to Consolidated EBITDA
shall not be greater than 3.0 to 1.0.

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.

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.

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4.   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 and
     (ii) 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.

5.   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.

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

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

8.   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.

9.   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 all 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 Sixth Amendment may be
     detached from any counterpart of this Sixth Amendment without impairing the
     legal effect of any signatures thereon and may be attached to another
     counterpart of this Sixth Amendment identical in form hereto but having
     attached to it one or more additional signature pages.

IN WITNESS WHEREOF, the parties hereto have executed this Sixth 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