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Exhibit 31.2

CERTIFICATION PURSUANT TO RULE 13a-14 AND 15d-14
UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

I, James J. TerBeest, Chief Financial Officer of the Registrant, Crdentia Corp.,
certify that:

      1. I have reviewed this quarterly report on Form 10-QSB of Crdentia Corp.;

      2. Based on my knowledge, this quarterly report does not contain any
untrue statement of a material fact or omit to state a material fact necessary
to make the statements made, in light of the circumstances under which such
statements were made, not misleading with respect to the period covered by this
quarterly report;

      3. Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
small business issuer as of, and for, the periods presented in this quarterly
report;

      4. The small business issuer's other certifying officer and I are
responsible for establishing and maintaining disclosure controls and procedures
(as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the small
business issuer and we have:

      (a)   designed such disclosure controls and procedures, or caused such
            disclosure controls and procedures to be designed under our
            supervision, to ensure that material information relating to the
            small business issuer, including its consolidated subsidiaries, is
            made known to us by others within those entities, particularly
            during the period in which this quarterly report is being prepared;

      (b)   evaluated the effectiveness of the small business issuer's
            disclosure controls and procedures and presented in this report our
            conclusions about the effectiveness of the disclosure controls and
            procedures as of the end of the period covered by this quarterly
            report based on such evaluation; and

      (c)   disclosed in this report any change in the small business issuer's
            internal controls over financial reporting that occurred during the
            small business issuer's most recent fiscal quarter (the small
            business issuer's fourth fiscal quarter in the case of an annual
            report) that has materially affected, or is reasonably likely to
            materially affect, the small business issuer's internal control over
            financial reporting; and

      5. The small business issuer's other certifying officer and I have
disclosed, based on our most recent evaluation of internal control over
financial reporting, to the small business issuer's auditors and the audit
committee of the small business issuer's board of directors (or persons
performing the equivalent functions):

      (a)   all significant deficiencies and material weaknesses in the design
            or operation of internal control over financial reporting which are
            reasonably likely to adversely affect the small business issuer's
            ability to record, process, summarize and report financial
            information; and

      (b)   any fraud, whether or not material, that involves management or
            other employees who have a significant role in the small business
            issuer's internal control over financial reporting.

Date:  November 15, 2004                             By: /s/  James J. TerBeest
                                                        ------------------------
                                                     James J. TerBeest
                                                     Chief Financial Officer