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                                                                    EXHIBIT 10.8
[LETTERHEAD OF ORTHOVITA(R)]

April 23, 2001

David J. McIlhenny
1963 Eva Drive
Lansdale, PA 19446

          RE:  Payments in the Event of Your Termination of Employment on a
               Change of Control of Orthovita, Inc.

Dear Dave,
          In connection with your position as Vice President, Quality Systems
and Operations Support for Orthovita, Inc. (the "Company"), the Board of
Directors of the Company (the "Board") has determined to provide you with a
continuation of your base salary in the event your employment with the Company
is terminated in connection with a "Change of Control" of the Company (as
defined in the Company's 1997 Equity Compensation Plan). Specifically, if within
one year after a Change of Control of the Company, (a) the Company terminates
your employment for any reason other than "Cause" (as defined in the Company's
1997 Equity Compensation Plan), your disability or death, or (b) you voluntarily
terminate employment with the Company on account of a "Constructive Termination"
(as defined below), you will receive a series of payments that is equal to a
continuation of your base salary, as in effect immediately prior to your
termination of employment, for a minimum of six (6) months but not to exceed
twelve (12) months. The payment of your base salary will continue until the
earlier of: (a) you start "Comparable Employment" (as defined below), or (b) the
first anniversary of your termination of employment with the Company. Your
entitlement to receive the payments described above will depend upon your
execution of the Company's standard separation of employment and general release
at the time of your termination of employment.

          A "Constructive Termination" is a termination of your employment at
your initiative after the occurrence of any of the following events without your
consent within one (1) year after a Change of Control of the Company: (a) a
material diminution in your duties, responsibilities, authority or status, (b) a
reduction in any amount of your annual base salary, or (c) the assignment to you
of duties or responsibilities which are materially inconsistent with the duties,
responsibilities, authority, or status of your position prior to the Change of
Control or materially impair your ability to function in your then current
position. "Comparable Employment" means that you start new employment with
another employer after your termination date that pays you a salary that is no
less than 75% of your base salary on your termination date and requires that you
perform the same or similar skill levels as when you were employed by the
Company.

          The foregoing payments are not additive or cumulative to severance
benefits that you might also be entitled to receive under the terms of a written
employment agreement, a severance agreement or any other arrangement with the
employer. Should you be entitled to receive severance benefits under the terms
of a written employment agreement, severance agreement or

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offer letter, you will receive the benefits from either this arrangement or the
prior arrangement, but not both. You will receive severance benefits under the
arrangement that provides the higher level of benefits.

          Your acceptance of the terms of the payments described above does not
provide you with the right to be retained in the service or employment by the
Company, and you will continue to be an "at-will" employee of the Company.

          Please acknowledge your consent to the payments described in this
letter by signing and returning this original letter to Pat Twomey. If you have
any questions concerning the payments, you may contact Human Resources at (610)
407-5215.

          Sincerely,

          /s/ Bruce A. Peacock

          Bruce A. Peacock
          President & Chief Executive Officer

          I consent to the terms of the payments described in this letter, and
understand that I am only eligible to receive the aforementioned payments if
within one year after a Change of Control of the Company either: (a) my
employment is terminated by the Company for any reason other than Cause,
disability or death, or (b) if I voluntarily terminate employment with the
Company on account of a Constructive Termination. I further understand that in
order to receive the payments provided in this letter I must execute the
Company's standard separation of employment and general release on the date I
terminate employment with the Company.

          /s/ David J. McIlhenny

          David J. McIlhenny
          MAY 24, 2001