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                                                                   EXHIBIT 10.10


                                 PROMISSORY NOTE


$500,000                                                          August 7, 2000


                  FOR VALUE RECEIVED, the undersigned, Alfred E. Brennan, an
Illinois resident (the "Payor") hereby promises to pay to the order of Young
Innovations, Inc., a Missouri corporation (the "Payee"), the principal sum of
Five Hundred Thousand Dollars ($500,000) (the "Principal"), together with
interest, from the date hereof on the Principal sum from time to time
outstanding at the rate provided below.

                  Payment of the Principal together with all interest thereon
shall be made upon the earlier to occur of the following (i) the termination of
Payor's employment with Payee or (ii) three (3) years from the date hereof. Upon
termination of Payee's employment for any reason, including but not limited to
death, disability, resignation or discharge (with or without cause), Payor
hereby consents and authorizes the Payee to deduct the amount, if any, due on
this Promissory Note (this "Note"), from such amount, if any, due Payor by
Payee, even if such amount exceeds fifteen percent (15%) of Payor's gross wages.
Interest on this Note shall accrue on the Principal amount outstanding from time
to time at a rate of 6.27% per annum and shall be payable on April 1st of each
year.

                  The Payor shall have the right to prepay this Note in whole or
in part, without premium or penalty of any kind. All payments hereunder shall be
applied first to accrued interest and then to the unpaid principal balance
hereof.

                  Payments of principal and interest on this Note shall be made
in such coin or currency of the United States of America as of the time of
payment shall be legal tender for public and private debts and shall be made to
Payee at Earth City, Missouri or at such other place as the holder hereof may
from time to time in writing direct.

                  The Payor agrees, subject only to any limitation imposed by
applicable law, to pay all costs of collection, including reasonable attorneys'
fees and legal expenses, incurred by the holder of this Note in endeavoring to
collect any amounts payable hereunder that are not paid when due whether by
acceleration or otherwise.

                  To secure payment of all amounts owed under this Note, the
undersigned hereby authorizes irrevocably, any attorney to appear for the
undersigned in any court and confess a judgment without process, in favor of the
Payee, for such amount as may appear to be unpaid thereon, together with
reasonable costs of collection, including reasonable attorney's fees, and to
waive and release all errors which may intervene in any such proceedings, and
consent to immediate execution upon such judgment, hereby ratifying and
confirming all that said attorney may do by virtue hereof.

                  The obligation of Payor to pay in full any amounts due or to
become due hereunder is absolute and unconditional and shall not be affected by
any dispute, claim, counterclaim, defense or other right which Payor may have to
assert against Payee.


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                  The undersigned expressly waives any presentment, demand,
protest, notice of default, notice of intention to accelerate, notice of
acceleration or notice of any other kind.

                  This Note shall be governed by and construed in accordance
with the internal laws of the State of Illinois.



                                              ----------------------------------
                                              ALFRED E. BRENNAN, JR.