Exhibit 4.1

COMMON STOCK COMMON STOCK BH BioHorizons, Inc. INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE SEE REVERSE FOR CERTAIN DEFINITIONS THIS CERTIFICATE IS TRANSFERABLE IN JERSEY CITY, NJ, NEW YORK, NY AND PITTSBURGH, PA THIS CERTIFIES THAT SPECIMEN IS THE RECORD HOLDER OF FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK, OF $0.0001 PAR VALUE, OF BioHorizons, Inc. transferable on the books of the Corporation by the holder hereof in person or by duly authorized attorney upon surrender of this certificate properly endorsed. This certificate is not valid unless countersigned and registered by the Transfer Agent and Registrar. Witness the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers. BIOHORIZONS® Dated: COUNTERSIGNED AND REGISTERED: MELLON INVESTOR SERVICES LLC TRANSFER AGENT AND REGISTRAR. BY AUTHORIZED SIGNATURE. Treasurer and Chief Financial Officer President and Chief Executive Officer CERTIFICATE OF STOCK

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: TEN COM — as tenants in common TEN ENT — as tenants by the entireties JT TEN — as joint tenants with right of survivorship and not as tenants in common UNIF GIFT MIN ACT — Custodian (Cust) (Minor) Act (State) UNIF TRF MIN ACT — Custodian (Cust) Under Uniform Transfers (Minor) to Minors Act (State) Additional abbreviations may also be used though not in the above list. FOR VALUE RECEIVED, hereby sell, assign and transfer unto PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) Shares of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint Attorney to transfer the said stock on the books of the within-named Corporation with full power of substitution in the premises. Dated NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE, IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT, OR ANY CHANGE WHATEVER. Signature(s) Guaranteed: By THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15. A statement of the powers, designations, preferences and relative, participating, optional or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights as established, from time to time, by the Certificate of Incorporation of the Corporation and by any certificate of determination, the number of shares constituting each class and series, and the designations thereof, may be obtained by the holder hereof upon request and without charge at the principal office of the Corporation.

BioHorizons, Inc. S-1/A