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                                                                    EXHIBIT 10.2

                                 PROMISSORY NOTE

Date:                      September 1, 1999

Maker:                     Mack E. Greder, D.D.S., P.C.

Payee:                     Pentegra Dental Group, Inc.

Place of Payment:          2999 N. 44th Street, Suite 650, Phoenix, AZ  85018

Principal Amount:          $272,000.00

         For value received, the undersigned, Mack E. Greder, D.D.S., P.C.
(hereinafter referred to as the "Maker") does hereby promise to pay to the order
of Pentegra Dental Group, Inc. (hereinafter referred to as the "Payee or
Holder"), the sum of Two Hundred Seventy-two Thousand and 00/100 Dollars
($272,000.00), plus interest at the rate of Nine Percent (9%) per annum on the
unpaid principal, until fully paid. The principal and accrued interest shall be
paid by the Maker in lawful money of the United States of America. The principal
and accrued interest on this note shall be due and payable in eleven (11) equal
monthly installments of Six Thousand Dollars ($6,000). The first installment
shall be due and payable on September 15, 1999 (the "Initial Payment Date") with
each installment due on the fifteenth of each month thereafter. The note shall
mature on August 15, 2000 with a balloon payment then due of Two Hundred
Fifty-four Thousand Eight Hundred Fifty-four and 00/100 Dollars ($254,854).
Payments shall be due and payable, at the principal office of the Payee or
Holder, on the monthly anniversary date of the Initial Payment Date. Each
installment shall be applied first to the payment of accrued interest due on the
unpaid principal balance, and the remainder of each installment shall be applied
to the reduction of the principal. Payment of this Note before maturity may be
made at any time, and from time to time, in whole or in part without penalty or
premium. Any such partial pre-payment of principal shall be applied against the
principal amount outstanding and shall not postpone the due date of any
subsequent monthly installments or change the amount of such installments unless
otherwise agreed in writing by Payee or Holder.

         Should default be made in the timely payment of interest or principal
due hereunder, and that default remain uncured for more than thirty (30) days
beyond its timely payment, (a "Non Payment Default") then that Non-Payment
Default shall mature the entire remaining indebtedness, without notice, at the
option of the Payee or Holder. The Maker and each Surety, endorser, and
guarantor, waives presentment for payment, all demands for payment, notice of
intent to accelerate maturity, notice of acceleration of maturity, protests, and
notices of protest. Maker consents that the Payee or Holder may extend the time
of any payment or any part of the debt at any time. Any delay on the part of the
Payee or Holder in exercising any rights granted by this Note shall not operate
as a waiver of those rights; and the acceptance of any payment after it's due
date shall not be deemed a waiver of the right to require prompt payment when
due of all other sums; and the acceptance of any payment after the Payee has
declared the entire indebtedness due and payable shall not cure any default of
the Maker nor operate as a waiver of any rights of Payee or Holder. This Note
shall be paid without claim of set off nor deduction of any nature whatsoever.


         In addition to the foregoing event of default (for Non-payment), at the
option of the payee or Holder, this Note shall become immediately due and
payable with notice on the happening of any one of the following additional
events of default ("Events of Default"):

                  a. The Maker has sold any interest in the professional
         practice of Mack E. Greder, D.D.S., P.C. or any of the assets located
         at 1113 North 72nd Street, Omaha, NE 68114, or any other dental
         practice owned by Maker with which Pentegra has


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         executed a service agreement (collectively the "Practice") without
         Pentegra's prior written consent;

                  b. The Maker has defaulted upon the obligations arising under
         the Service Agreement, Employment Agreement, or Dentist Agreement, by
         and between Maker and Pentegra Dental Group, Inc;

                  c. The Maker has mortgaged, pledged or encumbered the Practice
         to another party; except as such encumbrance may have arisen
         automatically by law or with prior written consent by the Payee or
         Holder;

                  d. The Maker makes a general assignment for creditors, is
         adjudicated bankrupt, files a voluntary petition in bankruptcy or
         reorganization or effects or attempts to effect a plan or other
         arrangement with creditors; or if Maker applies for a receiver,
         custodian or trustee for it or for any substantial portion or its
         property or assets; or if an order shall be entered by any court of
         competent jurisdiction approving an involuntary petition seeking
         reorganization; or if a receiver, trustee or custodian shall be
         appointed for it for any substantial portion of its property or assets;
         or if bankruptcy, reorganization or liquidation proceedings are
         instituted against the Maker and remain for thirty (30) days; or if the
         Maker becomes unable to meet its obligations as they mature; or if the
         Maker shall commit any act of bankruptcy;

         The events set forth in subparagraphs above (a)-(d) above shall not be
Events of Default until the Maker has been sent a notice from the Payee or
Holder of the Maker's default and Maker has not cured that Default within twenty
(20) days of such notice.

         The Maker agrees that, at any time that there remains an unpaid balance
due upon this Note, that the Payee or Holder shall have the right to sell,
assign, or transfer his right, title, and interest herein to any person (the
"Holder"); and further that the Assignee (Holder) shall then acquire all rights,
title, and interest that had been granted to the Payee or Holder hereunder.

         The Maker agrees that, if this Note is given to an attorney for
collection, or if suit is brought for collection, or if it is collected through
probate, bankruptcy, or other judicial proceeding, then Maker shall pay Payee or
Holder all costs of collection, including reasonable attorney's fees and court
costs, in addition to other amounts due.

         Any and all past due and unpaid principal and interest shall bear
interest at the rate of twelve percent (12.0%) per annum. However, all
agreements between Maker and Payee or Holder are hereby expressly limited, so
that in no event shall the amount paid, or agreed to be paid, to Payee or
Holder, exceed the maximum amount permissible under the applicable federal and
state usury laws. It is therefore the intention of Maker and Payee or Holder to
conform strictly to said state and federal usury laws. Therefore, in this note
or in any of the documents securing payment hereof, the aggregate of all
interest and any other charges constituting interest under the applicable law
contracted for, chargeable, or receivable, under this note shall under no
circumstances exceed the maximum amount of interest permitted by law. If any
excess of interest is provided for, or be adjudicated to be so provided for, in
this note or in any of the documents securing payment hereof, then in such
event, the provisions of this paragraph shall govern and control; and neither
Maker or Maker's heirs, legal representatives, successors, assigns, or any other
party liable for the payment hereof shall be obligated to pay the amount of such


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interest to the extent that it is in excess of the maximum permitted by law; and
any excess of said interest shall be deemed a mistake and is hereby canceled
automatically and if therefore paid, shall at the option of Payee or Holder of
this note be refunded to Maker, or credited to the principal amount of said
note; and the effective rate of interest shall be automatically subject to
reduction to the maximum lawful contract rate allowed under said laws, or as is
or as they may hereafter be construed by courts of appropriate jurisdiction. To
the extent permitted by law, the determination of the rate of interest shall be
made by amortizing, prorating, allocating, and spreading in equal parts during
the period of the full stated term of this note, all interest at any time
contracted for, charged, or received from Maker in connection therewith.

         THE MAKER AGREES THAT THIS WRITTEN NOTE REPRESENTS THE FINAL AGREEMENT
BETWEEN THE PARTIES CONCERNING THE AMOUNTS BORROWED BY MAKER, AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES. The Maker agrees that there are no unwritten oral
agreements between the parties. When the context requires, singular nouns and
pronouns include the plural.

         Executed this _________ day of _________________________, 1999.





                           ___________________________________
                           Mack E. Greder, D.D.S., P.C., MAKER
                           President

The undersigned, Mack E. Greder, D.D.S., does hereby individually, jointly and
severally guarantee the full, complete and punctual payment of this note.




                           ___________________________________
                           Mack E. Greder, D.D.S.
                           Individually as Guarantor



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