EXHIBIT 5.1

                         Posternak Blankstein & Lund LLP
June 16, 2004

National Dentex Corporation
526 Boston Post Road
Wayland, Massachusetts 01778

Re:  Registration Statement on Form S-8
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Ladies and Gentlemen:

This opinion is rendered to you in connection with the preparation of the
Registration Statement on Form S-8 (the "Registration Statement") under the
Securities Act of 1933, as amended (the "Securities Act"), by National Dentex
Corporation, a Massachusetts corporation (the "Company"), relating to an
additional 250,000 shares (the "Shares") of the Company's common stock, $0.01
par value per share (the "Common Stock") issuable upon the exercise of options
granted under the Company's 2001 Stock Plan, as amended, (the "Plan").

We have acted as counsel to the Company in connection with the preparation of
the Registration Statement. For purposes of this opinion, we have examined the
Company's Articles of Organization and By-laws, each as amended and restated;
the Plan; such record of the corporate proceedings of the Company as we have
deemed material; the Registration Statement and all exhibits thereto; and such
other documents as we have deemed necessary to enable us to render this opinion.

We are attorneys admitted to practice in The Commonwealth of Massachusetts. We
express no opinion concerning the laws of any jurisdiction other than the laws
of the United States of America and The Commonwealth of Massachusetts.

 In rendering the opinion expressed herein, we assume that all steps necessary
to comply with the registration requirements of the Securities Act and with
applicable requirements of state law regarding the sale of securities will be
duly taken.

Based upon and subject to the foregoing, and having regard for such legal
considerations as we have deemed relevant, it is our opinion that the Shares
have been duly authorized for issuance by all necessary corporate action and,
when issued and delivered against payment of the consideration therefore as set
forth in the Plan, will be validly issued, fully paid and nonassessable.

This opinion is rendered solely for your benefit, and may not be relied upon by
any other party without our prior written consent. We hereby consent to the
filing of this opinion as an exhibit to the Registration Statement and to the
reference to our name in the Registration Statement.

Very truly yours,

Posternak Blankstein & Lund LLP

By:   /s/ Michael L. Andresino
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      Michael L. Andresino,
      a Partner thereof

    Prudential Tower, 800 Boylston Street, 33rd Floor, Boston, MA 02199-8004


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